記述言語：日本語   掲載種別：研究論文（学術雑誌）  

添付ファイル： 論文.pdf

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

添付ファイル： AA149.pdf

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

添付ファイル： K.Suzuki_pp.69-74.pdf

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記述言語：日本語   出版者・発行元：公益社団法人 日本材料学会  

<p>Austenitic stainless steel was plastically deformed under uniaxial tension, and its plastic strain measured was 2.8%. The micro-residual stress were measured by the cos<sup>2</sup> <sub><i>X</i></sub> method using hard synchrotron X-ray with about 70 keV. The 2<i>θ</i>-cos<sup>2</sup> <sub><i>X</i></sub> diagrams for the 4 0 0 and 6 2 0 lattice planes, which belonged to a soft lattice plane, showed an upward warp. In contrast, the 2<i>θ</i>-cos<sup>2</sup> <sub><i>X</i></sub> diagrams for the 4 4 0 and 3 3 1 lattice planes, which belonged to a hard lattice plane, showed a downward warp. This is caused by the micro-residual strains such as intergranular strains. To investigate detail of the micro-residual stress by plastic deformation, the distributions of the residual strains were measured in omni-azimuth angles. As a result, the micro-residual strains for a soft lattice plane balanced with that for a hard lattice plane.</p>

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCI LTD  

The cos a method and the 2D method are well known as X-ray stress measurements using an area detector. Although the X-ray exposure of the cos a method occurs once, the accuracy of the center of the detector is required due to usage of the oblique incident X-ray beam. In the 2D method, the X-ray beams have to be applied from multiple orientations, and multiple measurements are required.
In this study, I propose a new method for X-ray stress measurement using an area detector. Its method is called the direct-method". The diffraction angles are measured with the area detector and the normal incident X-ray beam, and then the stresses are optimized by a simplex method. To examine effectiveness of the direct-method, I measured the residual stresses caused by water-jet peening. The stresses obtained were close to those obtained by the other method. It is discussed that precision of a detector center is important in usage of the area detector. In the case of the normal incident X-ray beam, the shape of the diffraction ring is an ellipse and has point symmetry at the origin. Using this property, the center of the area detector can be corrected. Further, the direct-method was applied to measuring the residual stresses coming from the grinding process. After correcting the center of the diffraction ring, the stresses which were optimized by the simplex method corresponded to those measured by the sin(2) psi method. In addition, the direct-method was extended to a cos alpha method.

DOI： 10.1016/j.ndteint.2017.07.012

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE SA  

Fatigue crack propagation behavior of a friction stir welded Ti-6Al-4V alloy was investigated with focus on the role of residual stresses and inhomogeneous microstructure. It was found that, in the weld affected areas, significant microstructural evolution occurred with alpha grain refinement, development of a bi-modal structure and increase in beta phase volume fraction. Residual stresses obtained through the XRD method were low, about 5% of the yield strength, in all regions of the weld. Fatigue crack propagation rates obtained through miniature CT specimens with initial notches in the base metal (BM), stirred zone (SZ), interfacial zone (IZ) and heat affected zone (HAZ) were higher in the SZ and the IZ. It was found, based on the coplanar maximum strain energy release rate theory, that the nominally linear crack propagation paths in the fine-grained structure of the SZ and IZ result in higher FCP rates than those of the torturous cracks in the BM. Considerations were also made with reference to the role of the increased beta volume fraction on the compliance of the SZ and IZ specimens. (C) 2015 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.msea.2015.11.065

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 日本材料学会  

DOI： 10.2472/jsms.64.675

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記述言語：日本語   出版者・発行元：日本保全学会  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：TRANS TECH PUBLICATIONS LTD  

The rotating-slit system was developed to overcome the measurement of internal stress using 2-dimensional detector. The diffraction spot trace method was proposed and examined to measure the internal stress of the material with coarse gains.

DOI： 10.4028/www.scientific.net/MSF.772.15

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：TRANS TECH PUBLICATIONS LTD  

The specimen material was austenitic stainless steel, SUS316L. The residual stress was induced by water-jet peening. The residual stress was measured using the 311 diffraction with conventional X-rays. The measured residual stress showed the equi-biaxial stress state. To investigate thermal stability of the residual stress, the specimen was aged thermally at 773 K in air to 1000 h. The residual stress kept the equi-biaxial stress state against the thermal aging. Lattice plane dependency of the residual stress induced by water-jet peening was evaluated using hard synchrotron X-rays. The residual stress measured by the soft lattice plane showed the equi-biaxial stress state, but the residual stress measured by the hard lattice plane did not. In addition, the distributions of the residual stress in the depth direction were measured using a strain scanning method with hard synchrotron X-rays and neutrons.

DOI： 10.4028/www.scientific.net/MSF.768-769.564

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：TRANS TECH PUBLICATIONS LTD  

A diffraction spot trace method (DSTM) is very useful to measure internal stresses of materials with coarse grains. In this study, validity of the DSTM was examined using high energy synchrotron X-rays of 70 keV. The specimen was a welded plate of austenitic stainless steel (SUS316L). The thickness of the specimen was 9 mm. The improved rotating slit-system was used, and PILATUS was used as an area detector. It was difficult to detect the high energy X-rays due to the reduction of counting efficiency of the PILATUS. However, the residual stress map of the welding specimen was obtained by long exposure time. The residual stresses of the welding specimen were simulated by a finite element method (FEM). The outline of the residual stress measured by the DSTM coincided with that by the FEM.

DOI： 10.4028/www.scientific.net/AMR.996.76

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：TRANS TECH PUBLICATIONS LTD  

The spiral slit-system was improved in order to make a gauge length regularity. The bending stress was measured by the improved spiral slit-system, and the measured stresses corresponded to the applied stress regardless of the diffraction angle. As a result, the validity of the improved spiral slit-system was proved. On the other hand, the diffraction spot trace method (DSTM), which combined the spiral slit-system and a PILATUS detector, was proposed to measure stress in a coarse grain. In this study, the distribution of the residual stress in a melt-run welding specimen was measured using the DSTM. The welding residual stresses measured accorded with that by the FEM simulation.

DOI： 10.4028/www.scientific.net/MSF.777.155

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 日本材料学会  

The spiral slit-system and DSTM (diffraction spot trace method) are under development in order to evaluate internal stresses of materials with coarse grains. The spiral slit-system was improved so that the length of the gauge volume is independent of the diffraction angle. The bending stress in the specimen with coarse grains was measured in order to confirm performance of this advanced spiral slit-system. The distribution of the measured bending stress coincided with the applied bending stress. As a result, it was proved that the combination of the advanced spiral slit-system and the DSTM is useful for the internal stress measurement of materials with coarse grains. The welded specimen of a Mg-alloy plate was prepared by melt-run with TIG welding. The residual stress map in the cross-section of the specimen was made using the DSTM. On the other hand, the residual stresses of the welded specimen were simulated by a finite element method. The measured residual stresses were similar to the simulated results, and the residual stresses due to extrusion were measured also using the DSTM. Therefore, the DSTM is suitable for the stress measurement of weld parts.

DOI： 10.2472/jsms.63.527

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本材料学会  

DOI： 10.2472/jsms.62.437

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 日本材料学会  

The specimen material was austenitic stainless steel, SUS316L. The residual stress was induced by water-jet peening. The residual stress was measured using the 311 diffraction with conventional X-rays. The measured residual stress showed the equi-biaxial stress state. To investigate thermal stability of the residual stress, the specimen was aged thermally at 773K in air to 1000h. The residual stress kept the equi-biaxial stress state against the thermal aging. Lattice plane dependency of the residual stress induced by water-jet peening was evaluated using hard synchrotron X-rays. The residual stress measured by the soft lattice plane showed the equi-biaxial stress state, but the residual stress measured by the hard lattice plane did not. In addition, the distributions of the residual stress in the depth direction were measured using a strain scanning method with hard synchrotron X-rays and neutrons.

DOI： 10.2472/jsms.62.437

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCI LTD  

Behavior of fatigue crack which was propagated at some representative areas in the friction stir welded (FSWed) joint of aluminum alloy 6063-T5 was studied. By extracting the T-L orientation specimens so that the loading axis on the fatigue test and the crack propagation direction were transverse and longitudinal to the welding direction, respectively, the crack propagation tests were carried out for both the as-welded and post-weld heat treated (PWHTed) FSWs at room temperature and 200 C. The experiments showed that the fatigue crack propagation (FCP) rates were sensitive to the propagating location, the test temperature, and the PWHT condition as well. It was also found that the different FCP rates were driven by the microstructural influences in and around the welded zone. While the residual stress was remarkable in the shoulder limit areas, it had a minor effect on the FCP behavior. (C) 2012 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.ijfatigue.2012.02.003

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本保全学会  

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記述言語：日本語   出版者・発行元：日本保全学会  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本保全学会  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：TRANS TECH PUBLICATIONS LTD  

Austenitic stainless steel (SUS316L) was used as specimen material, and the plate specimens were deformed plastically with a wide range of strain rates (6.67x10(-5)similar to 6.70x10(2)/s). The residual micro-stress for each lattice plane was measured with hard synchrotron X-rays. The residual macro-stress due to tensile deformation depended on strain rate. The residual micro-stresses varied from tension to compression, depending on the diffraction elastic constant. The soft lattice plane had tensile residual stress, and the hard lattice plane had compressive residual stress. The higher the strain rate, the smaller the difference in residual micro-stresses. The residual micro-stresses of the surfaces peened with the laser-peening or water-jet-peening were examined. Both surfaces had exhibited large compressive residual stress. The residual micro-stress on the peened surfaces showed a tendency opposite to residual micro-stress due to tensile deformation.

DOI： 10.4028/www.scientific.net/MSF.681.278

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本保全学会  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

A transmission imaging and a strain mapping in the vicinity of a crack tip in steel were investigated using a high energy white X-ray obtained from BL28B2 beam line at SPring-8 in Japan. Low-alloy and high-tensile steel was used as a specimen prepared in the G-type geometry with a rectangular sectional part of 5mm thickness for a four-point bending. A fatigue crack was introduced into the notch root on the tension side of the specimen by a pulsating bending load. The imaging of the crack in the specimen under the bending load was carried out by using the CCD camera that can detect indirectly the X-ray transmitted through the specimen. To measure the internal strain in the vicinity of the crack tip, the synchrotron white X-ray beam, which had a height of 80μm and a width of 300μm, was incident on the specimen with the Bragg angle θ of 5 degrees using the energy dispersive X-ray diffraction technique. As the results, the transmitted image of the crack showed that the crack in the specimen was propagated deeper than that on the surface. The map of the internal strain near the crack tip could be obtained using the white X-ray with energy ranging from 50keV to 150keV. It became clear by the numerical simulation that the FWHM of diffracted X-ray profile measured near the crack tip was increased due to the steep change in the strain distribution. It was confirmed that the synchrotron white X-ray was useful for the imaging of the internal crack and the strain mapping near it. © (2010) Trans Tech Publications.

DOI： 10.4028/www.scientific.net/MSF.638-642.2476

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：TRANS TECH PUBLICATIONS LTD  

Material of the specimen was austenitic stainless steel (SUS316L). The specimens were given tensile plastic strains from 0% to 55%. The Vickers hardness of the specimen corresponded to the plastic strain. The residual macrostress was measured by Mn-K alpha radiations. The residual macrostress of the annealed specimen had a small compression and changed into a tension after tensile plastic deformation. The specimen with 1% plastic strain showed the maximum tensile residual stress. To examine the dependency of the residual stress on the lattice plane, the residual microstress for each lattice plane was measured by hard synchrotron X-rays. The residual microstress was related with Young's modulus which was calculated by Kroner model. A new method, 2 theta-cos(2) chi method, was proposed to solve the problem of coarse grains and it was excellent in comparison with the sin(2) psi method.

DOI： 10.4028/www.scientific.net/MSF.652.7

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：TRANS TECH PUBLICATIONS LTD  

As the top coating, zirconia with 4 mol% yttria was electron beam-physical vapor deposited (EB-PVD) on the bond coating of CoNiCrAlY. The substrates were rotated during EB-PVD process and the rotation speeds were 5 (R5) and 10 rpm (R10) The thickness of the top coating was 0.12 mm. In order to investigate the change of the internal stress in the top coating under a heat cycle, the specimen was heated from a room temperature to 1293K, the internal stress was measured in-situ by a strain scanning method with hard synchrotron X-rays at each temperature step. For the specimen R5, the internal stress increased from about -100 MPa to about 100 MPa with the increase in temperature, then the stress relaxation of the top coating occurred over 1093K In the cooling process, the internal stress decreased, however, the changing rate of the internal stress was small as compared with the heating process. This was caused by the feather-like structure sintered. For the specimen R10, the internal stress did not show a tension in the heating process, it was caused by the separation between columnar structures.

DOI： 10.4028/www.scientific.net/MSF.638-642.906

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記述言語：日本語   出版者・発行元：公益社団法人 日本マリンエンジニアリング学会  

Recently, the third generation synchrotron radiation facility, SPring-8, is shared for industrial use. The hard X-ray in SPring-8 is a very intense narrow beam. Therefore, the stress distribution from the surface to the inside of a machinery member can be measured by high energy X-rays. In this paper, the stress scanning method is explained and the residual stress distribution of the laser-shocked Ti alloy is introduced. In the experiment with high energy white X-rays, the energy dispersive method had sufficient accuracy to measure the residual stress distribution. In addition, the neutron beam has a large penetration depth compared with that of a hard synchrotron X-ray. The stress measurement by neutron diffraction is applied to a large piston pin.

DOI： 10.5988/jime.44.744

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 日本材料学会  

As the top coating, zirconia with 4 mol% yittria was electron beam-physical vapor deposited (EB-PVD) on the bond coating of CoNiCrAlY. The substrates were rotated during EB-PVD process and the rotation speeds were 5 (R5) and 10 rpm (R10). The thickness of the top coating was 0.12 mm. In order to investigate the change of the internal stress in the top coating by a thermal cycle, the specimen was heated from a room temperature to 1273 K, the internal stress was measured in-situ by the strain scanning method with hard synchrotron X-rays at each temperature step. For the specimen R5, the internal stress increased from about –100 MPa to about 100 MPa with the increase in temperature, then the stress relaxation of the top coating occurred over 1073 K. For the specimen R10, the internal stress did not show a tension in the heating process, it was caused by the separation between columnar structure. In the cooling process, the internal stress decreased, however, the change rate of the internal stress was small as compared with the heating process. This was caused by sinterring of the feather-like structure.

DOI： 10.2472/jsms.58.562

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 日本材料学会  

Observation of the internal crack of steel by a computed tomography (CT) and strain mapping near its tip were investigated using a white X-ray obtained from BL28B2 beam line at SPring-8 in Japan. A low-alloy and high-tensile steel was used as a specimen prepared in the tensile bar with a parallel part of 5mm diameter. A fatigue crack was introduced into the specimen under the pulsating tension load (stress ratio R = 0). CT observation of the crack in the specimen was carried out by using the CCD camera that can detect indirectly the X-ray transmitted through the specimen. To measure the strain using the energy dispersive X-ray diffraction technique, the synchrotron white X-ray beam, which had a height of 100μm and a width of 100μm, was incident on the specimen with the Bragg angle θ of 5 degrees. As a result, the crack in the specimen under the tensile loading could be observed by the CT using the white X-ray. The resolution of CT, which was about 18μm<SUP>3</SUP>, was considerably lower than it using a monochromatic X-ray reported previously. The large tensile strain was measured near the crack tip. It was, however, relatively small under the influence of the long slender gauge volume as compared with the crack tip distributed circularly. It was confirmed that the FWHM of diffracted X-ray profile measured near the crack tip was increased due to the steep change in the strain distribution.

DOI： 10.2472/jsms.58.596

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2472/jsms.58.596

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本材料学会  

CONiCrNY was pressureless plasma-sprayed on a substrate of nickel-base superalloy as a bond coating. Under the substrate rotation, zirconia with 4mol% yttria was coated as the top coating by the electron beam-physical vapor deposition (EB-Pun). The rotation speed of the substrate was 5, 10 and 20rpm. The top coating was made by the columnar structure which consisted of the core part and the peripheral part, The top of the core part had a pyramidal shape made by piling up the zirconia (111) planes. The peripheral part showed feather-like structure, which was made by growth of the zirconia <100> and <111> directions. For the specimen with 20rpm, the in-plane residual stress was small within the range from-20 to 30MPa, the out-of-plane residual stress was a very small compression. By the increase in the rotation speed, the column becomes thick and the inter-columnar space becomes large. The substrate rotation is useful for the reduction of the residual stresses in the EB-PVD thermal barrier coaling.

DOI： 10.2472/jsms.57.674

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記述言語：日本語  

DOI： 10.2472/jsms.57.667

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本材料学会  

An imaging and a strain mapping in the vicinity of a crack tip in material were investigated using a high energy white X-ray obtained from BL28B2 beam line at Spring-8 in Japan. Low-alloy and high-tensile steel (JIS G3128 SHY685) was used as a specimen prepared in the G-type geometry. A fatigue crack was introduced into the specimen by a cyclic loading. The imaging of the crack in the specimen was carried out by using the X-ray CCD camera that can detect the X-ray transmitted through the specimen. To measure the strain, the synchrotron white X-ray beam, which had a height of 80μm and a width of 300μm, was incident on the specimen with the Bragg angle θ of 5 degrees using the energy dispersive X-ray diffraction technique. The internal strain in the vicinity of the crack tip was mapped out by scanning the irradiated X-ray position around it. As the results, the imaging of the crack, with about 1mm length, in the specimen under the loading of crack opening was practicable by using the synchrotron white X-ray. The map of the internal strain near the crack tip of the steel of 5mm thickness could be obtained using the white X-ray with energy ranging' from 50keV to 150keV. The plastic region estimated from the distribution of the FWHM of diffracted X-ray profile almost agreed with the theoretical value calculated by fracture mechanics. it was confirmed that the synchrotron white X-ray is useful for the imaging of the internal crack and the strain mapping near it.

DOI： 10.2472/jsms.57.667

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記述言語：日本語   出版者・発行元：日本機械学会  

The substrate material was nickel based superalloy (In738LC), CoNiCrAlY was pressureless plasma-sprayed on the substrate as the bond coating. As the top coating, zirconia with 4 mo1% yittria was made by a electron beam-physical vapor deposition (EB-PVD) with a rotation. The thickness of the bond coating was about 0.18 min, and the thickness of the top coating was about 0.12 mm. The rotation speeds of specimens in the EB-PVD process were 5rpm, 10rpm and 20 rpm. The specimens were exposed at 1273K for 200h. The in-plane residual stress was measured by a conventional X-ray method, and the out-of-plane residual strain was measured by a strain scanning method with hard synchrotron X-rays. For the specimens with 5rpm and 10rpm, the in-plane compressive residual stresses were released by the high temperature exposure. For the specimen with 20 rpm, the in-plane residual stress did not change by the high temperature exposure, because it was very small before the exposure. The in-plane residual stresses were large compression near the interface. For the specimens with 5 rpm and 10 rpm, the out-of plane stresses were small from the coating surface but became a compression near the interface. Both in in-plane and out-of-plane residual stresses of the specimen with 20 rpm were very small. In the effect of decreasing the residual stress, the rotation speed of 20 rpm was the excellent condition. According to the observation with a scanning electron microscope, the feather-like columnar structure decreased after the high temperature exposure. This volume decrease caused the release of the in-plane residual stresses.

DOI： 10.1299/kikaia.74.370

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

DOI： 10.1299/kikaia.74.302

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：TRANS TECH PUBLICATIONS LTD  

This paper presents a basic research on a measurement of strain in the bulk of materials by using high energy white X-ray from a synchrotron radiation source of SPring-8 in Japan. A high-tensile strength steel (JIS-SHY685) was used as a specimen loaded with bending. Strain distribution in it was evaluated by the energy dispersive method using diffracted X-ray transmitted through the specimen. As a result, the internal strain of high-tensile steel of 5, 10 and 15 mm thickness could be evaluated using white X-ray which range of energy from 50 keV to 150 keV. The measurement with a high degree of accuracy was accomplished using alpha-Fe321 diffraction in this material. The results showed that the internal strain measurement in the depth of the order of millimeter using the high energy white X-ray is practicable at SPring-8.

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：TRANS TECH PUBLICATIONS LTD  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本材料学会  

This paper presents a basic research on a measurement of strain in the bulk of materials by using high energy white X-rays from a synchrotron radiation source of Spring-8, WEL-TEN780E(JIS G3128 SHY685) whose grain size was 13μm was used as a specimen shaped into G type. The specimen was loaded with-bending. The white X-ray beam, which has a height of 50μm and width of 300μm , was incident in the specimen with the Bragg angle θof 5degree. Bending strain at the surface of specimen was measured by a strain gauge. The strain in the loading direction of the specimen was obtained directly from a rate of change of peak energy of transmitted X-rays through the thickness. As a result, the internal strain of SHY685 of 5mm thickness could be evaluated using white X-rays which range of energy from 60keV to 150keV. It is suitable for the measurement with sufficient accuracy to include more than or equal to 5000 grains of crystal in the gauge volume. The measurement error of strain could be decreased by using the diffracted X-rays with high energy. Furthermore, the measurement with a high degree of accuracy was accomplished using α-Fe321 diffraction in this material, The results showed that the high energy while X-ray is effective for internal strain measurements.

DOI： 10.2472/jsms.56.985

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本材料学会  

A plate of aTi alloy, Ti-6A1-4V, with a thickness of 9mm was laser-shock peened. The distribution of the residual stress throughout the plate thickness was nondestructively measured with the transmission and reflection conditions of the strain scanning method using hard synchrotron X-rays of 70keV energy. The distributions of the in-plane and out-of -plane strains were measured by using the 004 and 112 diffractions of α-Ti phase. In-plane strains measured in two perpendicular directions were nearly identical, confirming the equi-biaxial state of residual stresses. The out-of-plane strain measured for the 112 diffraction agreed with the value calculated from out-of-plane strains based on isotropic elasticity, while that for the 004 diffraction was higher than the prediction. The discrepancy for the case of the 004 diffraction was caused by the intergranular strain due to plastic anisotropy. The use of the 112 diffraction was recommended for the stress measurement. The residual stress on the surface was compression of about-500MPa and the compression zone extended about 1.8mm below the surface. The distribution of the half-value-breadth also shows a large increase in the subsurface compression zone.

DOI： 10.2472/jsms.56.217

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

The strain in the bulk of a material was evaluated using high energy white X-rays from a synchrotron radiation source at SPring-8. The specimen, which was a 5 mm thick austenitic stainless steel sample (JIS-SUS304L), was subjected to bending. The internal strain was measured using white X-rays, which ranged in energy from 60 keV to 125 keV. Highly accurate internal strain measurements were accomplished by simultaneously using strain data from several lattice planes of α -Fe. Furthermore, utilizing diffracted beams with a high energy, a high peak count, and a profile similar to a Gaussian distribution decreased the error of the strain measurement The results indicated that high energy white X-rays can effectively measure the internal strain at a millimeter depth. © 2007 American Institute of Physics.

DOI： 10.1063/1.2436368

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Thermal barrier coatings (TBCs) were made on cylindrical substrates with radii of 5, 10 and 15 mm. In addition to the cylindrical substrates, the TBC were also made on a plate substrate. First, NiCoCrAlY was pressureless plasma sprayed as a bond coating, and then zirconia with 8 mol% yittria was air plasma sprayed as the top coating. The TBC specimens were exposed in an atmosphere of air at 1373K for 0, 200 and 500 h. The radial strain was measured with the strain scanning method using hard synchrotron X-rays. The hoop and axial stresses of the cylindrical specimens were measured using laboratory X-rays with successive removal of the surface by polishing. Using these measured stresses and strains, the distributions of the 3-dimensional components of the residual stress in the top coating were determined. The spalling stress became a maximum at about 50mm from the interface. This position corresponded to the location of initiation of the spalling cracks. The value of the measured maximum spalling stress increased with the decrease in the radius of curvature. The difference of the measured distribution of the residual stress from the calculated distribution of the thermal stress was explained on the basis of the characteristics of the top coatings, such as the stress relaxation due to sliding between lamellae, a binding effect by the interface roughness and the spalling stress induced by the interface roughness. © 2007 Taylor &amp
Francis.

DOI： 10.1080/10238160701374030

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記述言語：日本語   出版者・発行元：日本材料学会  

The Ni-based superalloy IN738LC was used as the substrate material, and CoNiCrAIY powder was pressureless plasma-sprayed on the substrate as the bond coating. Zirconia was coated as the top coating by the electron beam-physical vapor deposition (EB-PVD) method. In the EB-PVD process, the specimens were kept at 1223K and rotated with 5rpm, 10rpm and 20rpm. According to the microscopic observation and the result of the pole figures, the top coalings had a columnar structure, which was made by the piling up of (111) planes. The cross section of the column had a diamond shape, and its diagonal was parallel to the rotation axis. The residual stress on the surface of the top coatings was evaluated by the X-ray diffraction method. Each diffraction profile was separated into the 133 and the 331peak, and the residual stress was measured by the sin^2Ψ method. The measured residual stresses were-76.7MPa for 5rpm, -63.0MPa for 10rpm and -25.1MPa for 20rpm.

DOI： 10.2472/jsms.56.588

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPAN SOC MECHANICAL ENGINEERS  

The surface aberration effect in the strain scanning method with a Ge analyzer was examined using high- energy X-rays from the undulator synchrotron source. The synchrotron X-rays from the undulator source had an enough intensity for the strain scanning method using a goniometer with the analyzer. The use of a Ge (111) analyzer showed remarkable reduction of the surface aberration effect. However, there still existed the surface aberration for the very-near surface region from the surface to the depth of 50 mu m. A correction method was proposed by taking into account of the effects of the divergence of the Ge analyzer, the mis-setting of the analyzer and the X-ray attenuation. The proposed correction method was very useful for eliminating the surface aberration effect. The correction method enables a high space-resolutive evaluation of the subsurface stress distribution. The method was successfully applied to the determination of the residual stress distribution of the shot-peened steel. A precise d(0) value of the strain-free lattice spacing necessary was determined from the surface stress measured by the conventional sin(2) psi method using Cr-K alpha radiation.

DOI： 10.1299/jsmea.49.376

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：社団法人日本材料学会  

A strain scanning method was applied to the stress measurement of austenitic stainless steel (SUS304L). The sizes of its gauge volume were a width of 2 mm and a height of 0.2mm, and the grain size of the specimen was 37 micrometers. Enough accuracy of the measured stress was not obtained due to the coarse grain of the specimen, To improve the coarse grain problem, three methods of oscillation were examined such as in-plane rotation, out-of plane tilt and translation. The translation method can increase the number of the grains by changing the amplitude. For the translation method, the accurate measurement is possible if it is 10000 numbers or more of grains. However, the numbers of the grains by the other oscillations were not enough. For the translation method, a strict parallel between the specimen surface and the translation plane was necessary. It succeeded in adjusting the strict parallel. The residual stress distribution of the shot-peened austenitic stainless steel was measured by our method.

DOI： 10.2472/jsms.55.647

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：社団法人日本材料学会  

Thermal barrier coatings (TBCs) were made on the round bar substrates of which radii were 5, 10 and 15mm. In addition to the round bar substrates, the TBC was made on a plate substrate. First, NiCoCrAlY was pressureless plasma-sprayed as bond coating, and then zirconia with 8 mol% yittria was air plasma-sprayed as top coating. The TBC specimens were exposed in air atmosphere at 1373K for Oh, 200h or 500h. The radial strain was first measured with the strain scanning method using high energy synchrotron X-rays. The hoop and axial stresses of the round bar specimens were measured using laboratory X-rays with successive removal of the surface by polishing. Using these measured stresses and strain, the distributions of the 3-dimentional components of the residual stress in the top coating were determined. The spalling stress became a maximum at about 50μm apart from the interface. This position corresponded to the location of initiation of the spalling cracks. The maximum of the measured spalling stress increased with the decrese in the radius of curvature. The difference of the measured distribution of the residual stress from the calculated distribution of the thermal residual stress was explained on the basis of the characteristic of the top coatings, such as the stress relaxation due to sliding between lamelli, a binding effect by the interface roughness and the spalling stress induced by the interface roughness.

DOI： 10.2472/jsms.55.634

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：社団法人日本材料学会  

When a gauge volume sank below a specimen surface, the diffraction angle shifts. Thus, it is required to correct the surface aberration. For the annealed specimen of S45C, the shift in the diffraction angle was investigated using a strain scanning method with Ge (111) analyzer. This phenomenon was caused by the difference in the centroid between the geometric and the instrumental gauge volumes. This difference is explained by the following factors; 1) the change in the gauge volume by the divergence of the analyzer, 2)the X-ray penetration depth, 3)the gap of the centre line between the double receiving slits due to mis-setting the analyzer. As a result, the correcting method considered into these factors was proposed. For the shot-peened specimens of S45C, the diffraction angles were measured and corrected by our method. The distribution of the residual stress agreed with that obtained by the removal method.

DOI： 10.2472/jsms.55.101

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

The surface aberration effect in the strain scanning method with a Ge analyzer was examined using high- energy X-rays from the undulator synchrotron source. The synchrotron X-rays from the undulator source had an enough intensity for the strain scanning method using a goniometer with the analyzer. The use of a Ge (111) analyzer showed remarkable reduction of the surface aberration effect. However, there still existed the surface aberration or the very-near surface region from the surface to the depth of 50 μm. A correction method was proposed by taking into account of the effects of the divergence of the Ge analyzer, the mis-setting of the analyzer and the X-ray attenuation. The proposed correction method was very useful for eliminating the surface aberration effect. The correction method enables a high space-resolutive evaluation of the subsurface stress distribution. The method was successfully applied to the determination of the residual stress distribution of the shot-peened steel. A precise d0 value of the strain-free lattice spacing necessary was determined from the surface stress measured by the conventional sin2 Ψ method using Cr-Kα radiation.

DOI： 10.1299/jsmea.49.376

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：TRANS TECH PUBLICATIONS LTD  

The strain in the bulk of material was evaluated using high energy white X-rays from a synchrotron radiation source of SPring-8 in Japan. An austenitic stainless steel (JIS-SUS304L) was used for a specimen. The specimen of 5 mm thickness was subjected to the bending. The internal strain of it could be measured using white X-rays which range of energy from 60 keV to 125 keV. The measurement of the internal strain with a high accuracy was accomplished using the strain data from several lattice planes of gamma-Fe simultaneously. Furthermore, the measurement error of strain could be decreased by using the diffracted beam with high energy, high peak count and the similar profile with the Gaussian distribution. The results showed that the high energy white X-rays is effective for the internal strain measurement in the depth of the order of millimeter.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：TRANS TECH PUBLICATIONS LTD  

A NiCoCrAlY bond coating was low-pressure plasma sprayed on a stainless steel substrate. Zirconia with 8 wt% yttria was deposited on the bond coating using an electron beam-physical vapor deposition (EB-PVD) method. The top coating had the preferred orientation with the (111) axis direction perpendicular to the coating plane. The distribution of the in-plane residual stress in the top coating was measured using laboratory Cr-K alpha X-rays with a progressive layer removal method. The value of the in-plane stresses was determined by the sin(2)psi method after the separation of the 133 and 331 peaks. The distribution of the out-of-plane strain in the top coating was measured using the strain scanning method with hard synchrotron X-rays. The out-of-plane strain was obtained from the 333 peak which had strong intensity due to the preferred orientation. The measured value of the in-plane stress in the top coating was a large compression, and showed a steep decrease near the interface between the top and the bond coatings. The distribution of the out-of-plane stress showed a compression, and its magnitude was smaller than that of the in-plane stress.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：TRANS TECH PUBLICATIONS LTD  

The strain scanning method was applied to the evaluation of the subsurface distribution of the residual stress beneath the shot-peened surface of an austenitic stainless steel SUS304L which had coarse grains and preferred orientation. The experiment was performed at beam line BL22XU at SPring-8 using monochromatic X-rays of 70.14 keV and a Ge (111) analyzer. The sizes of both incident and receiving slits were 2 x 0.2 mm(2). The specimens were annealed or shot-peened and had the dimensions of 20 x 20 x 5 mm(3). The grain size was about 37 mu m. In order to obtain the diffractions from an enough number of grains, various types of oscillation methods, which were translation, rotation and tilting of the specimen, were examined. The translational oscillation was found to be enough to obtain the accurate strain distribution. By combining the translational oscillation method with the correction to the surface aberration, the subsurface distribution of the residual stress of shot-peened austenitic stainless steel was successfully determined.

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記述言語：日本語   出版者・発行元：日本機械学会  

A residual stress distribution in thermal barrier coatings can be measured using the strain scanning method with high energy X-rays from a synchrotoron source due to its large penetration depth. For the double slits optics, the peak aberration of the measured diffraction becomes large, when the gage volume crosses the surface. The analytical correction method for the peak aberration was proposed in this paper. The surface aberration effect was corrected by taking account of the difference between the center of the goniometer and the optical centroid of the gage volume. Using the correction method, the distribution of the residual stress in thermal barrier coatings were measured from the surface to about 0.26mm inside. For the as-sprayed top coating, the in-plane residual stress was approximately 30 MPa, and out-of-plane stress increased near by interface. For the coating subjected to the heat cycle (1 773K), the both residual stress were relesed.

DOI： 10.1299/kikaia.71.1530

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記述言語：日本語   出版者・発行元：日本機械学会  

The distribution of the residual stress in the thermal barrier coating, which was made by an electron beam-physical vapor deposition (EB-PVD) method, was determined using X-ray stress measurements. As the bond coating, NiCoCrAlY was low-pressure plasma sprayed on the substrate of austenitic stainless steel. The 8 mass% Y_2O_3-ZrO_2 was coated on the bond coating using the EB-PVD method as the top coating. The top coating had the preferred orientation with the <111> axis direction perpendicular to the coating plane. The distribution of the in-plane residual stress in the top coating was measured using laboratory X-rays. The value of the in plane stresses was determined by the sin^2 ψ method after the separation of the 133 and 331 diffractions. The distribution of the out-of-plane strain in the top coating was measured using the strain scanning method with hard synchrotron X-rays. The out-of-plane strain was obtained from the 333 diffraction which had strong intensity due to the preferred orientation. The measured value of the in-plane stress in the top coating was a large compression, and steeply decreased near the interface between the top and the bond coating. The distribution of the out-of-plane stress showed a compression, and its magnitude was smaller than that of the in-plane stress.

DOI： 10.1299/kikaia.71.1523

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：社団法人日本材料学会  

The distribution of an out-of-plane stress, sigma σ3, in a thermal barrier coating (TBC) can be obtained from the combination of the data measured with laboratory X-rays and high-energy synchrotron X-rays. This method is called the hybrid method. To improve the hybrid method, the penetration depth is taken into account in the relation between a diffraction angle, 2θ, and sin^2Ψ. The distribution of the in-plane stress, σ1, was obtained by the stress measurement with laboratory X-rays after successive removal of the surface layer. Assuming the distribution of sigmaσ3 as a cubic function, the parameters of the function were optimized by minimizing the error between the measured and calculated 2θ- sin^2Ψ relations. In the top coating oxidized for 500h at 1373K, the out-of-plane stress became large tension near the interface between the top and the bond coating due to the interface roughness and the thermally grown oxide (TGO). For the top coating oxidized for 1000h, the TGO more grew and the out-of -plane stress near the interface was released due to the initiation of spalling cracks. However, the in-plane stress was maintained and the compressive stress region was extended. As a result, the behavior of the degradation of the oxidized TBCs corresponded to the change in the distributions of the residual stress.

DOI： 10.2472/jsms.54.679

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：TRANS TECH PUBLICATIONS LTD  

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記述言語：日本語   出版者・発行元：社団法人日本材料学会  

DOI： 10.2472/jsms.54.553

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：TRANS TECH PUBLICATIONS LTD  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

It is possible to measure nondestructively the residual stress in the interior of the top coating in the thermal barrier coating (TBC) using hard synchrotron X-rays, which have a large penetration depth and high brightness. A new hybrid method is proposed to estimate the distribution of the spalling stress in the top coating by combining the synchrotron data with the stress data measured by the conventional X-ray method utilizing a Cr-Kα radiation. The new hybrid method was applied to estimate the distribution of the spalling stress in the top coating of TBC which had a zirconia top coating with a thickness of 0.24 mm and a NiCoCrAlY bond coating with a thickness of 0.2 mm. The residual stress, σ11 - σ33, within the top coating was determined by synchrotron X-rays of 73 keV energy level, where σ33 was the stress perpendicular to the surface and σ11 was an in-plane stress. The distribution of residual in-plane stresses, σ11 and σ22, in the top and the bond coating was determined with the conventional X-ray method by repeating the measurement after successive removal of the surface layer. From the data obtained by synchrotron and conventional X-rays, the distribution of stress component, σ33, responsible for spalling was determined. The estimated value of the spalling stress was very small beneath the surface and increased to about 75 MPa near the interface between the top and the bond coating.

DOI： 10.1299/jsmea.47.318

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPAN SOC MECHANICAL ENGINEERS  

It is possible to measure nondestructively the residual stress in the interior of the top coating in the thermal barrier coating (TBC) using hard synchrotron X-rays, which have a large penetration depth and high brightness. A new hybrid method is proposed to estimate the distribution of the spalling stress in the top coating by combining the synchrotron data with the stress data measured by the conventional X-ray method utilizing a Cr-Kalpha radiation. The new hybrid method was applied to estimate the distribution of the spalling stress in the top coating of TBC which had a zirconia top coating with a thickness of 0.24 mm and a NiCoCrAlY bond coating with a thickness of 0.2 mm. The residual stress, sigma(11)-sigma(33), within the top coating was determined by synchrotron X-rays of 73 keV energy level, where sigma(33) was the stress perpendicular to the surface and sigma(11) was an in-plane stress. The distribution of residual in-plane stresses, sigma(11) and sigma(22), in the top and the bond coating was determined with the conventional X-ray method by repeating the measurement after successive removal of the surface layer. From the data obtained by synchrotron and conventional X-rays, the distribution of stress component, sigma(33), responsible for spalling was determined. The estimated value of the spalling stress was very small beneath the surface and increased to about 75 MPa near the interface between the top and the bond coating.

DOI： 10.1299/jsmea.47.318

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記述言語：日本語   出版者・発行元：日本機械学会  

A new hybrid method is proposed to estimate the spalling stress normal to the interface in thermal barrier coating. As the X-ray energy becomes higher, the penetration depth gets deeper. The in-plane stress, σ_1, is measured by the conventional X-ray with the low energy, and the out-of-plane stress, σ_1-σ_3, is measured by the synchrotron X-ray with high energy. The spalling stress, σ_3, can be estimated from two measurements obtained by the conventional and the synchrotron X-ray methods. The bond coating of NiCoCrAlY with a thickness of 0.2mm was made by plasma spraying on a Ni super-alloy substrate, and the ZrO_2 top coating with a thickness of 0.2mm was plasma sprayed on the bond coating. The distribution of the in-plane residual stresses, σ_1, in the top coating was measured with characteristic X-rays Cr-Kα by repeating the measurements after successive removal of the surface layer. The residual stresses, σ_1-σ_3, were measured by the synchrotron X-rays with 73 keV. The spalling stress was estimated from the stresses measured by the two methods. The spalling stress, σ_3, was small tensile beneath the surface of the top coat but increased to 75 MPa near the interface between the top and bond coatings. A high tensile stress near the interface may induce the delamination of coatings.

DOI： 10.1299/kikaia.70.724

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：社団法人日本材料学会  

An investigation was carried out into the effect of the interface roughness between the metallic bond coat and the ceramic topcoat on internal stresses in a thermal sprayed ceramic thermal barrier coating (TBC). To evaluate the effect of the interface roughness on the residual stress in the top coat, the specimens with two kinds of roughness were prepared. The interface roughness oh the bond coat was Ra = 5.8μm for the rough type specimen, and Ra = 3.5μm for the smooth type one. The in-plane stresses of the specimens were measured with laboratory X-rays. The inplane stresses for the both of the rough and smooth specimens were about GOMPa and independent of the roughness of the bond coat. Using high energy X-ray, the stress of the rough specimen was compressive and the stress of smooth specimen was tensile. This tendency is different from the result measured by laboratory X-ray. This difference in the stress value is coursed by the out-of-plane stress. These stresses in the topcoat were estimated by the hybrid method, that is to estimate out-of-plane stress using laboratory X-rays and high-energy synchrotron X-rays. As a result, the larger the roughness of the bond coat became the larger out-of-plane-stress become.

DOI： 10.2472/jsms.53.1019

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：社団法人日本材料学会  

As the bond coating, NiCoCrAlY powder was atmospheric plasma-sprayed on the Ni based super-alloy (In738LC), and the thickness of the bond coating was 0.15mm. Zirconia powder with 8mass% yttria was atmospheric plasma-sprayed as the top coating, and the thickness was 0.3mm. To oxidize the specimen, the specimens were kept in air at 1373K for 0, 500, 1000 and 2000h. The cross section of each oxidized specimen was observed with a scanning electron microscope. The thermally grown oxide (TGO) consists of the alumina layer and the composite oxide layer. The thickness of alumina layer stopped to increase after 500h exposure, while the thickness of the composite oxide layer incresed monotonically. The TGO grew at the convex part of the bond coating, and pushed up the top coating. As a result, the spalling crack was initiated near the convex part. The spalling stress for each oxidized specimen was estimated by the hybrid method using the stress data obtained by laboratory X-rays and high energy synchrotron X-rays. The top coating without the oxidization did not have the spalling stress. For the oxidized specimen, the spalling stress was small beneath the surface, and steeply increased near the interface between the top and the bond coating. The spalling stress near the interface was about 200MPa. The distribution of the spalling stress for the case of the 1000h exposure was similar to that for the case of 500h. The TGO promotes the spallation of the top coating, and the distribution of the spalling stress corresponds to the observed position of spalling cracks.

DOI： 10.2472/jsms.53.734

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1080/0733300310001634943

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：社団法人日本材料学会  

High-energy X-rays from a synchrotron radiation source, SPring-8, are available to obtain the microstructural information at deep positions inside the materials, because of its large penetration depth. Using the high-energy X-rays with an energy level of about 73keV, the internal stress in the bond coating was measured through the top coating in the thermal barrier coatings (TBCs) which consisted of a zirconia top coat with thickness of 0.24mm and a NiCoCrAlY bond coat with thickness of 0.2mm. A furnace, which could heat up the specimen up to 1473K was developed for the purpose of the in-situ stress measurement of the TBC in the goniometer at Beam Line BL02B1 of SPring-8. The diffraction of Ni_3Al-311 from the bond coat obtained through the top coat with about 0.24mm thickness was strong enough for stress determination. The internal stress in the bond coating was measured at the room temperature, 773K, 1073K and 1373K. The internal stress in the bond coat at a room temperature was tensile, and it was decreased with increase in temperature. At 1073K or higher, the internal stress in the bond coat was released due to softening of the bond coat. The change of internal stresses in the bond coat with temperatures was explained by thermal mismatch of expansion between top and bond coats.

DOI： 10.2472/jsms.52.756

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記述言語：英語   出版者・発行元：一般社団法人 日本機械学会  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：社団法人日本材料学会  

The in-depth distribution of residual stresses in shot-peened steels was measured by using high energy X-rays from a synchrotron radiation source. The relation between the 2θ and sin^2Ψ was obtained with the side-inclination method (Ψ diffractometer). The distribution of residual stresses was first evaluated by the nonlinearity of the sin^2Ψ diagram by a simplex method. The estimated stress agreed with the distribution determined through the sin^2Ψ method by using Cr-Kα radiation combined with the conventional surface removal method. A new method was proposed to estimate the stress value of the distributed residual stress. The new method was a combination of the side-inclination method and the iso-inclination method (ω diffractometer) to maintain the penetration depth constant. The sin^2Ψ diagram could be approximated by the linear relationship. The evaluated stress distribution agreed well with the distribution obtained by the surface removal method.

DOI： 10.2472/jsms.52.764

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記述言語：英語   出版者・発行元：一般社団法人 日本機械学会  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：一般社団法人日本機械学会  

A new method of nondestructive estimation of the in-depth distribution of residual stresses is proposed by using monochromatic high-energy X-rays from synchrotron radiation source SPring-8. The X-ray with 72 keV energy was used for stress measurements of shot-peened steel samples, whose compressive zone extended a few hundred micrometers below the surface. The measurements were carried out by using the sin<SUP>2</SUP> φ method in a Ψ-diffractometer. The obtained results of sin<SUP>2</SUP> φ diagrams showed nonlinearity due to the in-depth distribution of the residual stress. The stress distribution below the surface was estimated from the analysis to the nonlinearity of sin<SUP>2</SUP>φ dragrams. The estimated stress distribution agreed well with that determined by the conventional sin<SUP>2</SUP> φ method with Cr-Kα radiation corrected by surface removal effect.

DOI： 10.1299/kikaia.69.993

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その他リンク： https://jlc.jst.go.jp/DN/JALC/00229769047?from=CiNii

記述言語：日本語   出版者・発行元：日本放射光学会  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：TRANS TECH PUBLICATIONS LTD  

A high-energy X-ray beam from a synchrotron radiation source, SPring-8, was used to determine the residual stress distribution below the shot-peened surface of a carbon steel plate. By using the monochromatic X-ray beam with three energy levels of 30, 60 and 72 keV, the stress values were determined by the sin(2)psi method with the side-inclination method (psi diffractometer). The stress value was estimated from the slope of the linear approximation of the relation between 26 and sin 2W in the range of sin(2)psi = 0 to 0.5. The estimated stress agreed with the distribution off the residual stress measured by removing the surface layer and repeating the X-ray measurement with Cr-Kalpha radiation. The nonlinearity of the sin(2)psi diagram can be used to estimate the distribution of the residual stress. A new method was proposed to estimate the stress value of the distributed residual stress. The new method was a combination of the side-inclination method and the iso-inclination method (omega diffractometer) to maintain the penetration depth constant. The stress value at a given penetration depth was successfully determined by the new method.

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：社団法人日本材料学会  

This paper described a new nondestructive measurement of the in-depth distribution of residual stresses by using monochromatic high energy X-rays from synchrotron radiation source of SPring-8. The measurement was carried out by using the sin^2 ψ method with the Ψ-diffractometer. It was first proved to have a high accuracy in measuring the loading stress by four-point bending. The diffractions with five different penetration depths obtained by X-rays with three energy levels, 30, 60, and 72 keV, were adapted to measure the residual stress below the surface of shot-peened steels. The residual stress distribution measured by five penetration depths agreed well with the residual stress distribution determined by the conventional Cr-Kα radiation combined with the method of the successive removal of the surface layer by electropolishing. The compressive zone extended 150 and 300μm below the surface depending on the intensity of shot peening.

DOI： 10.2472/jsms.51.756

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：社団法人日本材料学会  

A new method is proposed to estimate nondestructively the distribution of the equibiaxial residual stress beneath the surface by using an Eulerian cradle type goniometer. By maintaining a constant value of the X-ray incident angle, the probing depth of X-rays is kept nearly constant, even though sin^2 ψ is changed. From the slope of the linear relation between the diffraction angle and sin^2 ψ, the stress value is calculated for a given probing depth. This new method is applied to estimate the residual stress of a shot-peened steel sample, whose compressive zone extended about 150μm below the surface. High energy X-rays of 72keV from synchrotron radiation source, SPring-8, was used for stress measurements. The residual stress distribution estimated by the new method agreed well with that determined by the conventional sin^2 ψ method with Cr-Kα radiation combined with the method of the successive removal of the surface layer by electropolishing.

DOI： 10.2472/jsms.51.1429

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その他リンク： https://jlc.jst.go.jp/DN/JALC/00161528948?from=CiNii

記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：日本語   出版者・発行元：日本機械学会  

Accurate values of X-ray elastic constants are required for a reliable stress measurement of thermal barrier coating films (TBC films). In this paper, atmosphere and pressureless plasma sprayed TBC films were removed from substrates, then X-ray elastic constants of both TBC films were determained by using newly developed tensile jig. For the atmosphere plasma sprayed film, the value of the mechanical elastic constant was much smaller than the X-ray elastic constant owing to cracks or pores existing in the films. The X-ray elastic constant of the atmosphere plasma sprayed TBC film was nearly equal to that of the pressureless plasma sprayed film. This means that the X-ray elastic constants are little influenced by cracks or pores. Residual stress distributions in both films coated on the substrates were obtained. In the surface region with the depth up 60 μm, residual stresses of both films showed a drastic variation. This variation of the residual stresses was build up during rapid quenching and solidifying of the molten droplet. In deeper regions, residual stresses were nearly constant. These constant values of residual stresses are caused by the thermal strain mismatch between the TBC film and the substrate.

DOI： 10.1299/kikaia.67.417

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2472/jsms.49.12Appendix_249

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

The X-ray elastic constants of pressureless sintered βsilicon nitride (Si3N4), were experimentally determined for ten different diffractions by using Ka radiations of Cu, Co, Fe, Cr and V. The X-ray compliances, (1+v'x)/ E'x and v'xl E'x (Ex=Young's modulus, v'x=Poisson's ratio), change as a second power function of cos20 (ø=angle between the diffraction plane normal and the c-axis of hexagonal crystal). Using the simplex method, the elastic constants of single crystals of P-silicon nitride were determined from the measured values of the X-ray compliances on the basis of the average of Voigt and Reuss models and Kroner's model, combined with the self-consistent analysis of multi-phase materials. The obtained result shows a high stiffness in the c-direction of hexagonal crystals, but the degree of anisotropy is not so large as the whisker data reported by Hay et al. © 2000, The Society of Materials Science, Japan. All rights reserved.

DOI： 10.2472/jsms.49.12Appendix_249

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：社団法人日本材料学会  

Thermal barrier coating (TBC)of 8 wt% Y_2O_3-ZrO_2 was made by low-pressure plasma spraying. The coated film with 0.3 mm in thickness was removed from the substrate of Nimonic-263 by electropolishing. Tension and compression tests of removed films were conducted by using a specially designed gap jig.TBC films showed stress relaxation while keeping the displacement constant both tensile and compressive deformation. The X-ray method was used to measure the stress in the TBC film under bending. The stress measured by the X-ray method changed proportionally to the bending stress up to the magnitude of about 10 MPa both in tension and compression. When the bending stress of about 20 MPa was applied to the films, the X-ray stress did not increase because of sliding of the lamella structure. The sliding stress between lamellae was determined from the residual curvature of films after bending. It was about 10 MPa, which agreed with limit stress measured by the X-ray method.

DOI： 10.2472/jsms.49.117

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：社団法人日本材料学会  

DOI： 10.2472/jsms.48.308

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：社団法人日本材料学会  

DOI： 10.2472/jsms.48.1147

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記述言語：英語   出版者・発行元：一般社団法人日本機械学会  

The sin&#039; Ψ diagram taken from a specimen with steep stress gradients beneath the surface shows nonlinearity, because the X-ray penetration depth changes depending on the tilt angle. Stress gradients can be determined from this nonlinearity. Since ceramic materials have deep X-ray penetration depth, the thickness of a ceramic thin film should have a significant effect on the nonlinearity of the sin^2Ψ method, In this paper, we propose a method of X-ray measurement of the stress gradient, which takes into account film thickness under the assumption of linear stress distributions. A 58-μm-thick silicon nitride film was prepared. The film specimen was polished carefully with diamond slurry to obtain sharp profiles of the X-ray diffraction. To obtain a steep stress gradient, the specimen was bent on a cylinder. The stress distribution estimated by the present method agreed well with the applied bending stress. In conclusion, the stress gradient should be analyzed by the weighted average stress on the basis of the intensity of the diffracted X-rays from the entire thin film, when the thickness is six times larger than the effective X-ray penetration depth.

DOI： 10.1299/jsmea.41.416

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPAN SOC MECHANICAL ENGINEERS  

The sin(2) psi diagram taken from a specimen with steep stress gradients beneath the surface shows nonlinearity, because the X-ray penetration depth changes depending on the tilt angle. Stress gradients can be determined from this nonlinearity. Since ceramic materials have deep X-ray penetration depth, the thickness of a ceramic thin film should have a significant effect on the nonlinearity of the sin(2) psi method. In this paper, we propose a method of X-ray measurement of the stress gradient, which takes into account film thickness under the assumption of linear stress distributions. A 58-mu m-thick silicon nitride film was prepared. The film specimen was polished carefully with diamond slurry to obtain sharp profiles of the X-ray diffraction. To obtain a steep stress gradient, the specimen was bent on a cylinder. The stress distribution estimated by the present method agreed well with the applied bending stress. In conclusion, the stress gradient should be analyzed by the weighted average stress on the basis of the intensity of the diffracted X-rays from the entire thin film, when the thickness is six times larger than the effective X-ray penetration depth.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPAN SOC MECHANICAL ENGINEERS  

The residual stress distribution of ground ceramics was determined from the eigen strain distributed near the ground surface. The eigen strain of ground ceramics was tensile, and exponentially decreased with the distance from the surface. The residual stress distribution is given as a superposition of an exponential function of compression and a linear function. It is found that the actual residual stress distribution can be approximated by an exponential function of compression because the magnitude of tensile residual stress is negligibly small compared to the compressive residual stress. In the experiments, the diffraction angle was measured on ground silicon nitride for a wide range of sin(2) psi using the glancing incidence X-ray diffraction technique. A strong nonlinearity was found in the 2 theta-sin(2) psi diagram at very high psi-angles. From the analysis of nonlinearity, the residual stress distribution was determined. The residual stress distribution of silicon nitride coincided with the distribution calculated from the eigen strain distribution. Transmission electron microscopy was used to clarify the origin of generation of the residual stress. Both strain contrasts and microcracks were observed below the ground surface; straight dislocations were also observed within silicon nitride grains near the ground surface.

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記述言語：日本語   出版者・発行元：日本機械学会  

The residual stress distribution of ground ceramics was determined from the eigen strain existing in the ground surface. The eigen strain of ground ceramics was tensile, and exponentially decreased with the distance from the surface. The residual stress distribution is given as a superposition of all exponential function of compression and a linear function. It is found that the actual residual stress distribution call be approximated by a compressive exponential function because the magnitude of tensile residual stress is negligibly small compared to the compressive residual stress. In the experiments, the diffraction angle was measured on ground silicon nitride for a wide range of sin^3Φ using the glancing incidence X-ray diffraction technique. A strong nonlinearity was found in the 2θ-sin^2Φ diagram at very high Φ-angles. From the analysis of nonlinearity, the residual stress distribution was determined. The residual stress distribution of silicon nitride coincided with the distribution calculated from the eigen strain distribution. Transmission electron microscopy was used to clarify the origin of generation of the residual stress. Both strain contrasts and microcracks were observed below the ground surface : straight dislocations were also observed within silicon nitride grains near the ground surface.

DOI： 10.1299/kikaia.63.1681

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記述言語：日本語   出版者・発行元：日本機械学会  

The sin^2 ψ diagram taken from a specimen with steep stress gradients beneath the surface shows nonlinearity because the X-ray penetration depth changes depending on the tilt angle. Stress gradients can be determined from this nonlinearity. Since ceramic materials have a deep X-ray peretration depth, the thickness of a thin ceramic film should have a significant effect on the nonlinearity of the sin^2 ψ method. In this paper, we propose a method of X-ray measurement of the stress gradient which takes into account of the effect of the thickness of a film under the assumption of linear stress gradients. The film made of silicon nitride was prepared. A 58 μm thick film specimen was carefully polished with diamond slurry to obtain sharp profiles of the X-ray diffraction. To apply the linear stress gradients, the specimen was bent on a cylinder. The stress distribution estimated by the present method agreed well with the applied bending stress, From the present study, stress gradients should be analyzed in terms of the weighted average stress on the basis of the whole intensity of the diffracted X-rays from thin films. when the thickness is less than six times the effective X-ray penetration depth.

DOI： 10.1299/kikaia.63.1243

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記述言語：日本語   出版者・発行元：社団法人日本材料学会  

The distribution of residual stress near the surface of ground ceramics is very steep. In the X-ray stress measurements of specimens with large stress gradient, the sin^2ψ diagram is nonlinear because of the change in X-ray penetration depth with X-ray tilt angle ψ. The stress measured by the X-ray method is a weighted average of the stresses over the X-ray penetration depth. However, the X-ray penetration depth has been taken rather arbitrary in the previous X-ray studies of steep stress distributions. In the present study, a steep stress gradient was generated in bending of a thin plate of silicon nitride of thickness 108 μm, and this applied stress was analyzed by the cosψ and parabola methods of X-ray measurement of stress gradient. The penetration depth is concluded to be infinite, and the range of the integral of the weighted average is from the surface of infinite depth. The thickness of about six times the effective penetration depth is enough to ensure the infinite range of integration. Several sources of errors in the measurement of stress gradient were discussed on the basis of numerical simulations.

DOI： 10.2472/jsms.45.759

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：COMPUTATIONAL MECHANICS PUBLICATIONS LTD  

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記述言語：日本語   出版者・発行元：社団法人日本材料学会  

A new experimental system was developed to record the optical microscopic image of slow crack growth in ceramics together with the applied stress value. The bending stress was applied to pressureless-sintered alumina with Vickers indentation cracks, and the slow crack growth behavior was observed with this new system. The relation between the applied stress intensity factor K_&lt;app&gt; and P/c^&lt;3/2&gt;(P=the indentation load, c=the half crack length)becomes linear with the crack extension. From the linear relation, the fracture toughness K_∞ for long cracks and a χ parameter in equation K_&lt;res&gt;=χ・P/c^&lt;3/2&gt;(K_&lt;res&gt;=the stress intensity factor due to indentation residual stress)were obtained. The incrreasing R-curve for small cracks was determined by using the above determined χ parameter. The resistance became constant as the crack extension was longer than 0.15 mm, and this constant value was identical to the fracture toughness determined by using a single-edge-precracked beam.

DOI： 10.2472/jsms.44.1133

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記述言語：日本語   出版者・発行元：社団法人日本材料学会  

The surfaces of bending specimens of silicon nitride were ground in two different grinding directions with a diamond wheel. One was parallel and the other was perpendicular to the longitudinal direction of specimens. The Weibull distribution of the bending strength of ground specimens was compared to that of lapped specimens. The average fracture strength normal to the grinding direction fell by about 25% in comparison with the average strength of lapped specimens. The residual stress distribution near the ground surface was measured by the cosψ method of X-ray stress measurement. The stress state was biaxial. One of the pricipal directions of stresses was along the grinding direction. Both of the principal residual stresses, σ_1 and σ_2, were compressive and decreased exponentially with increasing the distance from the surface. The residual stress was diminished at about 30μm in depth. The increment of strength due to compressive residual stresses was determined by calculating the stress intensity factor of a semi-elliptical surface crack in the residual stress field. The size of grinding flaws degrading bending strength was estimated from the relation between the fracture strength and the surface crack size. The depth of grinding flaws parallel to the grinding direction ranged approximately from 40 to 70 μm;the deepest point of flaws was out of the zone of compressive residual stresses.

DOI： 10.2472/jsms.44.1127

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SOC MATERIALS SCIENCE, JAPAN  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2472/jsms.44.501Appendix_134

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JSME  

Since the critical size of defects in ceramics is usually very small, the conventional method of fracture mechanics prediction often becomes inapplicable. In the present study, the fracture strength of silicon nitride with small defects is evaluated on the basis of the R-curve method. The parameters of the R-curve of silicon nitride are determined from the experimental relationship between the fracture strength and the defect size. For penny-shaped cracks, the fracture strength is constant for small defects and the critical stress intensity factor is constant for large defects. The equivalent defect size is an excellent parameter to correlate the fracture strength to the size of elliptical cracks with an aspect ratio between 0.3 and 1. For small voids, the fracture strength is nearly the same as that for a penny-shaped crack. On the other hand, for large voids, the fracture strength approaches a constant value which is equal to that of materials without voids divided by the elastic stress concentration factor. When the tip radius of deep long notches is small, the critical stress intensity factor for fracture is independent of the tip radius. A Monte Carlo simulation of bending fracture of silicon nitride was performed by randomly distributing penny-shaped cracks having random sizes in a specimen by a computer. On the basis of twenty-five runs of fracture simulation, the relationship between the bending strength and the equivalent defect length, and cumulative distribution function of the fracture strength were successfully derived.

DOI： 10.1299/jsmea1993.38.3_347

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：社団法人日本材料学会  

Specimens of tetragonal containing 3mol% Y_2O_3 were ground wetly and dryly with a grinding wheel of grain size 200/230. The residual stress and the monoclinic content were measured by the X-ray diffraction method. The monoclinic content on the surface ground wetly with enough coolant was raised to about 7 percent. For wet ground Y-TZP, bending stress was applied in directions parallel and perpendicular to the grinding direction. The bending strength in both directions increased because of compressive residual stress. Fracture did not start from grinding cracks. For Y-TZP ground dryly without coolant, the bending stress was applied in the direction pallaled to the grinding direction. Many grinding cracks were introduced on the ground surface and no compressive residual stress was measured. Since the ground surface was heated to a high temperature, the transformation to the monoclinic phase did not occur. The bending strength of dry-ground Y-TZP was reduced remarkably. The breadth of X-ray line broadening measured on the dry-ground furface was larger than that of the wet-ground surface. The depth of the grinding-affected zone was 10μm for the dry-ground surface and 30μm for the wet-ground surface.

DOI： 10.2472/jsms.43.779

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記述言語：日本語   出版者・発行元：日本機械学会  

Specimens of tetragonal zirconia containing 3 mol % Y_2O_3 (Y-TZP) were ground with a diamond wheel of grain number 200/230. The residual stress and the monoclinic content were measured by the X-ray diffraction method. The bending stress was applied in the directions parallel and perpendicular to the grinding direction of the specimen. The residual stress on the ground surface was compressive, and the compression zone extended to about 30 μm in depth. The monoclinic content on the ground surface was raised to 7 to 8 percent. The bending strength increased in both directions because of the residual compressive stress near the surface introduced by grinding. For ground specimens, defects at the nucleation site of bending fracture were pores or coarse grains, but not grinding defects. Since the lower content of Y_2O_3 near the nucleation site raised the toughness of the material, the fracture toughness for fracture from small defects was larger than that of the single edge precracked specimen. The increase in the Weibull modulus due to grinding was discussed on the basis of fracture mechanics.

DOI： 10.1299/kikaia.59.1353

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記述言語：日本語   出版者・発行元：日本機械学会  

Since the critical size of defects in ceramics is normally very small, the conventional method of fracture mechanics often becomes inappropriate. In the present paper, the fracture strength of silicon nitride with small defects is evaluated based on the R-curve method. Parameters of the R-curve of silicon nitride are determined from the experimental relationship between the fracture strength and the defect size. For penny-shaped cracks, the fracture strength is constant for small defects and the critical stress intensity factor is constant for large defects. The equivalent defect size is an excellent parameter for correlating the fracture strength with the size of elliptical cracks with an aspect ratio between 0.3 and 1. For small voids, the fracture strength is nearly the same as that for a penny-shaped crack. On the other hand, for large voids, it approaches a constant value which is equal to the strength of materials without voids divided by the elastic stress concentration factor. When the tip radius of long deep notches is small, the critical stress intensity factor for the fracture is independent of the tip radius. A Monte-Carlo simulation of bending fracture of silicon nitride was performed by random distribution of penny-shaped cracks with random sizes in a specimen by a computer. On the basis of twenty five runs of fracture simulation, the relationship between the bending strength and the defect size, and the cumulative distribution function of the fracture strength were successfully derived.

DOI： 10.1299/kikaia.59.1292

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記述言語：日本語   出版者・発行元：公益社団法人日本セラミックス協会  

Fracture toughness (K_&lt;IC&gt;) of CVD ・ TiC-SiC composites with columnar structure was measured by the indentation microfracture method. In order to explain the resulting high fracture toughness, residual stress in the composites was measured by the X-ray diffraction method (2θ-sin^2ψ method). Crack deflection was observed in both surfaces perpendicular and parallel to columnar structure of TiC-SiC composites, more pronounced with the latter. The K_&lt;IC&gt; values were about three to four times as large as that of monolithic SiC or TiC, and were about twice as large as sinterd TiC-SiC composites with TiC-dispersed type of structure. It was presumed that the residual stress in the CVD・TiC-SiC composites was much larger than that in monolithic SiC or TiC, and the values parallel to the columnar structure of the composites was larger than that perpendicular. From above result, it was considerd that the high fracture toughness of CVD・TiC-SiC composites was achieved by crack deflection, the effect of which depended on the residual stress in the composites.

DOI： 10.2109/jcersj.100.835

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：CERAMIC SOC JAPAN-NIPPON SERAMIKKUSU KYOKAI  

Fracture toughness (K(IC)) of CVD . TiC-SiC composites with columnar structure was measured by the indentation microfracture method. In order to explain the resulting high fracture toughness, residual stress in the composites was measured by the X-ray diffraction method (2-theta-sin2-psi method). Crack deflection was observed in both surfaces perpendicular and parallel to columnar structure of TiC-SiC composites, more pronounced with the latter. The K(IC) values were about three to four times as large as that of monolithic SiC or TiC, and were about twice as large as sinterd TiC-SiC composites with TiC-dispersed type of structure. It was presumed that the residual stress in the CVD . TiC-SiC composites was much larger than that in monolithic SiC or TiC, and the values parallel to the columnar structure of the composites was larger than that perpendicular. From above result, it was considerd that the high fracture toughness of CVD . TiC-SiC composites was achieved by crack deflection, the effect of which depended on the residual stress in the composites.

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：ELSEVIER APPL SCI PUBL LTD  

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記述言語：日本語   出版者・発行元：日本機械学会  

X-Ray stress measurement was applied to TiC and SiC monolithic films and TiC/SiC composite films coated by CVD process on graphite substrates. Textures of films were examined by the X-ray diffraction method. TiC coating had preferential growth of the (2 2 0) plane. SiC coating had preferential growth of the (1 1 1) plane. TiC/SiC composite coating showed a strong texture of the (2 2 0) plane perpendicular to the substrate surface. The diffractions from TiC (3 3 1) and SiC (3 3 1) planes by Fe-Kα characteristic X-rays are suited for X-ray residual stress measurement in thin films. In TiC/SiC composite coating, X-ray diffraction profiles from the TiC phase and SiC phase overlap. These line profiles were separated into TiC and SiC line profiles by the modified DFP method. Phase stresses in the TiC phase and SiC phase in TiC/SiC composite coating showed a triaxial stress state. The measured residual stress of the TiC phase is tensile and that of the SiC phase is compressive. Although the surface residual stress in SiC monolithic coating with thicknesses below 30μm was compressive, the residual stress was tensile for thick coating, and increased with increasing film thickness.

DOI： 10.1299/kikaia.58.2172

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：PERGAMON PRESS LTD  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：ELSEVIER APPL SCI PUBL LTD  

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記述言語：日本語   出版者・発行元：日本機械学会  

This paper deals with the change in shape of the front surface of vacuum chuck employed for ultra precision machining due to the centrifugal force generated by the rotation of the spindle. Displacement, change in shape of the front surface and the diametrical expansion of the chuck made of aluminum are analysed experimentally under several contact conditions. Deformation analyses of the chuck by FEM based on several models for the ordinary contact condition are also carried out to compare with the experimental result. It is clarified that the axial and radial deformations of the aluminum chuck agree well between the experiment and the FEM analysis based on a model with fixed contacts at the interface between the chuck and the spindle. Deformation of another type of chuck consisting of a combination of steel and aluminum parts is also analysed.

DOI： 10.1299/kikaic.57.3280

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：社団法人日本材料学会  

Alumina ceramics was coated on mild steel by a detonation gun with different quantities of detonation gas, and the residual stress in the coated film was measured by using the X-ray diffraction from the (844) plane ofγ-alumina by Cu-K α radiation. The mechanical Young&#039;s modulus increased with decreasing amount of cracks and pores in the coated film made under a larger quantity of detonation gas. The X-ray Young&#039;s modulus was larger than the mechanical one because the strain measured by X-rays was the average of crystalline phases. The residual stress measured by X-rays was tension and distributed uniformly in the coated film. The tensile residual stress was smaller for the coat made with larger gas quantity. It was rather insensitive to the film thickness and also to the surface grinding.

DOI： 10.2472/jsms.40.96

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：社団法人日本材料学会  

Most of engineering ceramics are finished by grinding. Residual stresses and defects introduced into ceramics during grinding are two main factors which influence the strength of ground ceramics. In the present study, the specimens of pressureless sintered silicon nitride were ground by a diamond wheel of #170/200 grain size number in the longitudinal direction, and the bending strength perpendicular to the grinding direction was determined by four point bending. The residual stress measured by the X-ray method was compression on the ground surface and the compression zone extended about 20μm. The bending strength of ground specimen was lower than that of buffed standard specimens. The size of grinding flaws was estimated from the bending strength and the residual stress distribution by using the effective crack length model. The estimated flaw depth of 45μm agreed with the crack measured on the edge surface of the specimen. The bending strength of ground specimens was recovered by removing the surface layer by about 40μm. This recovery agreed with the model prediction based on the flaw depth estimated above.

DOI： 10.2472/jsms.40.818

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

Phase stresses in alumina and zirconia phases of composite ceramics were measured by using the X-ray diffractions from Al&lt;SUB&gt;2&lt;/SUB&gt;O&lt;SUB&gt;3&lt;/SUB&gt; (1. 0. 10) and ZrO&lt;SUB&gt;2&lt;/SUB&gt; (133) by Cr-Ka radiation. Under tension, the phase stress in each phase increased linearly with the applied strain. The stress in Al&lt;SUB&gt;2&lt;/SUB&gt;O&lt;SUB&gt;3&lt;/SUB&gt; was larger than that in ZrO&lt;SUB&gt;2&lt;/SUB&gt;. The macrostress calculated from phase stresses by the rule of mixture was equal to the applied stress. The residual macrostress was compression on the ground surface. The compressive residual macrostress was larger with increasing the diamond grain size of a cutting wheel. For a given grinding condition, it was larger in the direction perpendicular to the grinding direction than in the parallel direction. The microstress in Al&lt;SUB&gt;2&lt;/SUB&gt;O&lt;SUB&gt;3&lt;/SUB&gt; was compression, while that in ZrO&lt;SUB&gt;2&lt;/SUB&gt; was tension. The compressive macrostress zone extended about 10 to 15 &amp;mu;m in depth from the surface for the cases of grinding by #600 and #200 diamond wheels. The broadening of the X-ray diffraction profile was also detected within this zone.

DOI： 10.1299/kikaia.56.402

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：社団法人日本材料学会  

The X-ray diffraction method was used to measure the phase stress in composite ceramics of zirconia mixed with 20 and 40 wt% alumina which were subjected to elastic bending. The phase stress each phase was determined from the diffraction of Al_2O_3(146), Al_2O_3 (1.0.10) and ZrO_2(133). The phase stress increased in proportion to the applied stress ; the proportional constant was larger for Al_2O_3 than for ZrO_2. The macrostress calculated from the phase stresses by using the rule of mixture was nearly equal to the applied stress.athe theoretical calculation based on the self-consistent model of elastic deformation of composites gave a lower phase stress to Al_2O_3 and a higher phase stress to ZrO_2 when compared with the experimental results. The theoretical analysis should be elaborated to include the influences of the free surface and the third phase on phase stresses.

DOI： 10.2472/jsms.39.1235

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：社団法人日本材料学会  

Preassureless sintered aiumina with 92% purity was quenched from 1500 ℃ into silicon oil with the kinematic viscosity of 1,100 and 10000cs. The residual stress distribution in the quenched ceramicus was measured by the X-ray diffraction method. The increase of the bending strength of quenched ceramics was discussed on the basis of the measured residual stress. The results obtained were summarized as follows: The compressive residual stress was formed near the surface of quenched ceramics, and its magnitude increased with decreasing viscosity of silicon oil. The bending fracture of quenched ceramics started from the material defect en~ibedded in the surface layer with large compressive residual stresses. The bending strength increased in proportion to the amount of compressive residual stress measured on the surface. The maximum strength was obtained for the case of quenching into 1 cs silicon oil. It was 531 MPa which is about 1.4 times tbe strength of annealed specimens. The microscopic residual stress, estimated from the broadening of the X-ray diffraction profile, could reduce the stress for fracture from a small (microscopic) defect.

DOI： 10.2472/jsms.39.590

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

The X-ray elastic constants and the stress constant for the X-ray stress measumement of partially stabilized tetragonal zirconia with 2.5 mol% and 3 mol% yttria were determined for diffractions from plane (0 2 6) by Cu-K&amp;alpha; radiation and from plane (1 3 3) by Cr-K&amp;alpha; radiation. The X-ray value of E/(1+ v) (E=Young&#039;s modulus, v=Poisson&#039;s ratio) was rather insensitive to the conditions of sintering and surface finishing. The measured value for plane (1 3 3) was lower than that for plane (0 2 6). The accuracy of the X-ray stress measurement was found to be higher for the case of plane (1 3 3). The residual stresses measured on the ground, lapped and polished surfaces were all compressive. The &amp;Psi; splitting of the sin&lt;SUP&gt;2&lt;/SUP&gt; &amp;Psi; diagram was observed for the cases of heavy grinding. The magnitude of the compressive residual stress became larger with increasing the diamond grain size of a cutting wheel, while it was insensitive to the cutting depth. The full width at the half maximum of the X-ray diffraction profiles and the amount of transformation from the tetragonal phase to the monoclinic phase also increased with increasing the diamond grain size of a cutting wheel.

DOI： 10.1299/kikaia.55.318

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：社団法人日本材料学会  

The X-ray elastic constants of composite ceramics of ziruconia mixed with 40wt% alumina wee determined by X-ray stress measurements and compared with theoretical perdiction. The results obtained are summarize as follows: (1) The X-ray elastic constants were determined for the diffraction from Al_2O_3 (1 4 6) plane by Cu-Kα radiation, and for those from Al_2O_3 (1.0.10) and ZrO_2 (1 3 3) planes by Cr-Kα radiation. The X-ray values of E_x&#039;/(1+ν_x&#039;) and E_x&#039;(E_x&#039;=Young&#039;s modulus, ν_x&#039;=Poisson&#039;s ratio) of the composite decreased in the alumina phase and increased in the zirconia phase when compared with those of single-phase ceramics. (2) The values of E_x&#039;/(1+ν_x&#039;) for Al_2O_3(1 4 6), Al_2O_3(1.0.10) and ZrO_2(1 3 3) planes of the composite calculated from those of single-phase ceramics on the bases of Hauk&#039;s model agreed fairly well with the experimental values. The value of E_x&#039; /(1+ν_x&#039;) for the alumina phase in the composite calculated from the elastic constants of single crystals on the basis of Eshelby&#039;s model was slightly larger than the experimental value. The contribution of pores in the composite should be included in modeling.

DOI： 10.2472/jsms.38.840

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：社団法人日本材料学会  

The X-ray diffraction method was used to measure the residual stress on and beneath the surfaces of sintered alumina and silicon nitride ground with diamond wheels of # 200 and # 80 grain-size numbers. The residual stress measured on the ground surface was the largest compression on the surface of silicon nitride ground with a # 80 diamond wheel. The depth of the compression zone from the surface was between 20 and 30 μm. The compressive residual stress due to grinding with a # 200 diamond wheel improved the bending strength of ceramics. On the other hand, gringing with # 80 diamond wheel often introduced flaws into ceramics, reducing the benefitcal effect of the compressive residual stress. The effect of gringing residual stress on the relation between the bending strength and the defect size was discussed on the basis of fracture mechanics. A model was proposed to assess the effects of the residual stress and the material defect on the bending strength of ceramics.

DOI： 10.2472/jsms.38.582

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：社団法人日本材料学会  

The effects of notch shape and effective case depth on the rotating bending fatigue limit of induction surface hardened S45C steel were investigated. The results are summarized as follows; (1) In the case of fracture from the inner part of test specimens, the fatigue limit became higher with increasing α and ECD. The reason is that the applied stress at the notch root become higher with increasing α, and the residual compressive stress at the notch root decreases with increasing ECD. However, when α exceeded a certain value, nonpropagating cracks were recognized and the fatigue limit became almost constant. (3) From the effects of α and ECD on fatigue limit, it is said that the fatigue limit becomes higher with increasing ECD in the case of α&lt; 2, while in the case of α&gt; 2, the fatigue limit increases with decreasing ECD and the crack initiation strength increases with increasing ECD.

DOI： 10.2472/jsms.37.178

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：社団法人日本材料学会  

The X-ray elastic constant of sintered alumina with powder purities of 99%, 96% and 92% was determined for two diffraction planes, (2. 1. 10) and (1 4 6), by using Fe-Kα and Cu-Kα radiations. The effects of purity and diffraction plane on the X-ray elastic constant were studied. The results obtained were summarized as follows:(1) The diffraction from the (2. 1. 10) plane yielded higher accuracy in the X-ray stress measurement of sintered alumina than that from the (1 4 6) plane, because of its high intensity, isolation of the diffraction profile, and low magnitude of the stress constant. (2) The X-ray value of the elastic constant, E/(1 + ν)(E= Young&#039;s modulus, ν= Poisson&#039;s ratio), as well as the mechanical value, became smaller with decreasing purity or bulk density. The ratio of the X-ray elastic constant to the mechanical value did not vary with bulk density for the both diffraction planes. (3) A simple method to estimate the X-ray elastic constant of sintered alumina with arbitrary bulk density was proposed on the basis of the Reuss-model analysis of alumina polycrystals.

DOI： 10.2472/jsms.37.586

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：社団法人日本鉄鋼協会  

Purposes in this study are to estimate validity of linear fracture mechanics for thermal shock cracking and to clarify the behavior of stretched zone width in thermal shock. Thermal shock tests were carried out with carbon steel (S53C). Thermal shock was given by jet water on the fatigue precracked surface. The following results were obtained ; 1) At a given temperature, thermal shock crack length can be correlated with the maximum value of stress intensity factor which was caused by unsteady thermal stress (maximum stress intensity factor). 2) Stretched zone width is proportional to the temperature of crack tip at the time when stress intensity factor becomes maximum. Stretched zone width decreases, as the increase rate of stress intensity factor rises. The above was also confirmed by results on a different size test specimen.

DOI： 10.2355/tetsutohagane1955.71.11_1510

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記述言語：日本語  

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記述言語：日本語   出版者・発行元：新潟大学教育学部  

In this paper, we propose a learning program for "Energy Conversion" in "Technology and Home Economics (Technology)" at Junior high school. As an important subject, this program features a power flow between radio transmitter and radio receiver in Wireless LAN (WLAN) system, i.e. the conversion from electric power to radio wave, radio wave propagation in the space considered, and the conversion from radio wave to electric power. Students study all of the energy conversions within limited range of time, by using computer simulation tools for electromagnetic wave analyses (ray tracing analysis tool, FD-TD analysis tool, and so forth) for getting beautiful color image of electric field distribution in their school WLAN environment. By reading the image obtained, the students can easily understand whether or not they are in good positions for reception of the radio wave. This learning procedure is based on an application of the computer simulation technologies, so this can also be applicable to a program (algorithm and programing education) for "Information Study by Scientific Approach" in "Information" at High School. In the program, next, to validate the simulation results and detect insensitive zones of their school WLAN, actual electric field distribution (signal strength) in the school is simply measured by using ICT device as tablet PC, in which the FREE app with simplified field strength measurement function is installed. At the end of the program, a collaborative learning practice is carried out for the purpose to discuss a common problem among the students and evaluate it quantitatively. The collaborative group working may also be extended to a subject for "the Period for Integrated Studies".

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記述言語：日本語   出版者・発行元：新潟大学教育学部  

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記述言語：日本語   出版者・発行元：新潟大学教育学部  

This paper proposes a simple and effective ICT utilization method for safely and efficiently learning appropriate usage of woodworking tools (saw, planer, hammer, nailing tools, etc.) at a class of "Technology of Materials and Their Processing" in "Technology and Home Economics (Technology)" at Junior high school. Here we construct a simplified multi-angle motion/position monitoring apparatus by using tablet PCs and an electric interactive white board (or a large-screen LCD TV), which have already been equipped in ordinary classroom in Japan. Here, in addition to the above ICT devices, a special access point with screen projection function is introduced. By using the monitoring apparatus in wood processing training, students can easily check whether or not they are operating the wood processing with appropriate motion and/or position. As the result, it is expected by introducing the apparatus that the students can improve their wood processing techniques by themselves safely and efficiently.

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記述言語：日本語   出版者・発行元：新潟大学教育学部  

In this paper, the background and history of constituting &quot;energy conversion&quot;, which is a learning area, were described. The problems of curriculum organization was pointed out. For examples, the school hour of the technical education was reduced by &quot;yutori&quot; education and the international convention on the elimination of all forms of discrimination against women. As a result, the constitution of energy conversion was unreasonable. To improve &quot;energy conversion&quot;, a newteaching material was proposed from a view-point of mechanical engineering.

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記述言語：日本語   出版者・発行元：新潟大学教育学部  

In this paper, we introduce a part of our practical training programs for training on fundamental electric/electronic circuit in Faculty of Education, Niigata University. Here, simple LED based circuit including a microcontroller is utilized in the training (8 LEDs and 1 microcontroller are used). The training program is provided to the students who want to be the teachers of the course "Technology and Home Economics (Technology)" in our university. The contents of the training are related to the field "B. Technology of energy conversion" in the course, as shown in the current "The new Courses of Study for elementary and junior high schools (announced in March 2008)".Furthermore, by executing a programming education on the microcontroller and some ingenious schemes, it can provide the students with the advanced educational effects related to "computer programming", "collaborative learning", and "ICT utilization in education". Our electronic circuit training simply comprises the following four items as 1) LED circuit implementation using a breadboard, 2) LED circuit implementation on a circuit board using soldering method, 3) Programing for the microcontroller on the circuit using PC and the related devices (The 8 LEDs on the circuit can be turned on and off under complete control), and 4) Collaborative learning practice by connecting the circuits into one board and programming it collaboratively.

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記述言語：日本語   出版者・発行元：新潟大学教育学部  

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記述言語：日本語   出版者・発行元：新潟大学教育学部  

In this study, a role of mechanical engineering in machining learning was described. Without understanding mechanical engineering, machining learning tends to fall into merely working. Technical education has a strong influence on science education. The decrease in school hours of technology education was one of the reasons for science phobia. The content of mechanical engineering which was concerned with machining learning was demonstrated. We introduced the mechanical engineering practice for the technology teacher education. In addition, the practice was examined from a viewpoint of active learning.

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記述言語：日本語   出版者・発行元：新潟大学教育学部  

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記述言語：日本語   出版者・発行元：新潟大学教育学部  

In this paper, we introduce our new improved information network practice environment for "ICT utilization in education" in Niigata University. The practice environment is open for all the students who want to be teachers in Niigata University. It provides them with stable broadband internet access via very high-speed gigabit wired LAN system with independent network nodes and user authentication function, and secure network area to safely carry out the security measure to their computers and related ICT devices without risk of computer virus infection. It was re-constructed in two ordinary lecture rooms (204 and 105 lecture rooms in the building of our faculty). The rooms are equipped with large number of information receptacles connecting to the Internet and power receptacles connecting to AC 100V electric source, so more than 200 students can simultaneously do the fundamental information network practice or information security practice. Also, in addition to the fundamental practices, they can do additional applied exercise for ICT utilization in education appropriate for each curriculum in teacher-training courses for elementary, junior high, and high schools.

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記述言語：日本語   出版者・発行元：新潟大学教育学部  

This paper proposes a simple solution for a teacher to easily construct intra-school wireless LAN (WLAN) environment in an ordinary classroom. No special knowledge on ICT and the related technologies is required in the construction procedure. The teacher only connects some cables between the prepared three components as 1) access point, 2) LCD projector, and 3) HDMI screen projection device. These devices are all low-priced. It also takes about 3 to 4 minutes to complete the WLAN environment. The proposed solution is not only simple but also has enough performance to connect all of the teacher&#039;s and learners&#039; information terminals in the classroom via the constructed WLAN. The system makes it possible to share data in the information terminals on the LCD projector with ease. So the proposed simple WLAN environment may be a help to spread and accelerate the ICT utilization in education in Japan, even for small boards of education with difficulties in developing an appropriate ICT system.

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記述言語：日本語   出版者・発行元：新潟大学教育学部  

In this paper, we introduce our efforts to improve educational effects on&quot; information security measure&quot; for all the students who want to be teachers in Niigata University, in the pre-training guidance hosted by Faculty of Education, Niigata University, in collaboration with Center for Academic Information Service, Niigata University. Our security guidance simply comprises the following four items as 1) Understanding and dissemination of&quot; information security policies&quot; not only for university but also for practice schools (for the boards of education where the practice schools belong to), 2) Requirement of filling out and submitting &quot;security check sheet&quot; for the students who want to bring their computers and the related ICT devices to the schools, 3) Human support for the students who do not have enough skill to carry out the security measure procedure to their computers by themselves, and 4) Providing secure environment for them to safely do the security measure to their computers without risk of computer virus infection.

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記述言語：日本語   出版者・発行元：日本保全学会  

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記述言語：日本語   出版者・発行元：新潟大学教育学部  

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記述言語：日本語   出版者・発行元：ナショナルピーアール  

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

Experimental technique using area detectors is very important for the stress measurements of welding parts and materials with large grains. In this presentation, the direct method, which is a new stress analysis using an area detector, is proposed. The di

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記述言語：日本語   出版者・発行元：発電設備技術検査協会溶接・非破壊検査技術センター  

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DOI： 10.14920/jwstaikai.2011f.0.120.0

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記述言語：日本語   出版者・発行元：一般社団法人 溶接学会  

ショットピーニングを施した異材溶接継手に320℃の熱サイクルを複数回付与して表面の圧縮残留応力の変化を調査した結果，初めの1サイクル目で圧縮残留応力は大幅に低下し，その後のサイクルで大きな変化は見られなかった．1サイクル目の付与前後の残留応力分布をSPring-8のビームラインで詳細に調査した結果，異材境界部近傍で圧縮残留応力が大幅に低下する傾向が見られた．

DOI： 10.14920/jwstaikai.2011f.0.120.0

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記述言語：日本語   出版者・発行元：一般社団法人 日本機械学会  

The specimen material was austenitic stainless steel SUS3 16L. The plastic tensile specimens were prepared using tensile testing machine and split-Hopkinson bar test. The residual micro-stresses of these specimen were measured by many lattice plane using hard synchrotron X-ray. The higher the strain rate, the smaller the difference in the residual micro-stress. In addition, the residual micro-stress on laser-peened and water-jet peened surfaces were examined by hard synchrotron X-ray.

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記述言語：日本語   出版者・発行元：一般社団法人 日本機械学会  

Cold spray method is solid coating process, can reduce a heat influence on materials and can make a uniform coating without oxide. The residual stress is a problem in many industries and it needs to measure nondestructively. In this study the residual stress of cold sprayed Ni coatings was measured using neutron diffraction method at RESA in JRR-3 of JAEA. The coating of 5mm thick is sprayed on the SUS304 stainless steel plate. The three direction residual stress (σx, σy, σz) in every 1mm of sprayed coatings was measured. The in-plane stress was a compression near the coating surface and changed to a tension close to the interface between coating and substrate and was an equi-bi-axial stress state. The out-of-plane stress near the interface had a tension due to a plane strain stress state.

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記述言語：日本語   出版者・発行元：新潟大学教育学部  

ln a strain scanning method with hard synchrotron X-rays, the stress measurement of materials with coarse grains is one of challenging assignments. As measures of the coarse grain problem, an advanced strains canning method was proposed in this paper. In this method, the gauge volume is scanned under rotating the sample, consequently the scanning stage has to set on the rotating stage. The special stage, which we had made using as lip-ring mechanism, enabled the proposed method. The diffraction angles of the annealed S45C sample were measured by the strain scanning method with a rotation. The diffraction angles were constant and the surface aberration effect did not appear. Therefore, the strain scanning method with arotation demonstrated the excellent correction of the surface aberration effect. The diffraction profiles of the shot-peened austenitic stainless steel of SUS304L were measured by the strain scanning method without arotation, but the residual stress distribution was not obtained due to the distorted profiles. On the other hand, the residual stress distribution of the same specimen could be measured using the strain scanning method with a rotation. Asaresult, this method is useful for the stress measurement of coarse grains.

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記述言語：日本語   出版者・発行元：日本材料学会  

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記述言語：日本語   出版者・発行元：日本マリンエンジニアリング学会  

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記述言語：日本語   出版者・発行元：新潟大学教育学部  

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記述言語：日本語   出版者・発行元：日本材料学会  

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記述言語：日本語   出版者・発行元：一般社団法人 日本機械学会  

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記述言語：日本語   出版者・発行元：電気加工学会  

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記述言語：日本語   出版者・発行元：電気加工学会  

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記述言語：日本語   出版者・発行元：一般社団法人 日本機械学会  

The strain in the bulk of material was evaluated using high energy white X-rays from a synchrotron radiation source of SPring-8 in Japan. An austenitic stainless steel (JIS-SUS304L) was used for a specimen. The specimen of 5mm thickness was subjected to the bending. The internal strain of it could be measured using white X-rays which range of energy from 60 keV to 125 keV. The measurement of the internal strain with a high accuracy was accomplished using the strain data from several lattice planes of γ-Fe simultaneously. Furthermore, the measurement error of strain could be decreased by using the diffracted beam with high energy, high peak count and the similar profile with the Gaussian distribution. The results showed that the high energy white X-rays is effective for the internal strain measurement in the depth of the order of millimeter.

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記述言語：日本語   出版者・発行元：一般社団法人 日本機械学会  

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記述言語：日本語   出版者・発行元：一般社団法人 日本機械学会  

Thermal barrier coatings (TBCs) were made on the cylindrical substrates of which radii were 5mm, 10mm and 15mm. In addition to the cylindrical specimens, the TBC was made on a plate substrate. As the bond coating, NiCoCrAlY was pressureless plasma sprayed, and then zirconia with 8 mole percents yittria was air plasma sprayed as the top coating. The TBC specimens were exposed in the atmosphere at 1373K for 0h, 200h and 500h. The hoop and axial stress of the specimens were measured with laboratory X-rays and the radial strain was measured with high energy synchrotron X-rays. As a result, the spalling stress became a maximum at about fifty micron meters to the surface side from the bond coating interface. This position corresponded to the location of initiation of the spalling cracks.

DOI： 10.1299/jsmemecjo.2005.6.0_251

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記述言語：日本語   出版者・発行元：一般社団法人 日本機械学会  

Thermal barrier coatings (TBCs) were made on the cylindrical substrates of which radii were 5mm, 10mm and 15mm. In addition to the cylindrical specimens, the TBC was made on a plate substrate. As the bond coating, NiCoCrAlY was pressureless plasma sprayed, and then zirconia with 8 mole percents yittria was air plasma sprayed as the top coating. The TBC specimens were exposed in the atmosphere at 1373K for 0h, 200h and 500h. The distributions of the 3-dimentional residual stress in the top coating were measured by laboratory X-rays and hard synchrotron X-rays. Comparing the residual stress distribution by the experiment with that by the analysis, the characteristic of the top coatings made by plasma-spraying was clarified.

DOI： 10.1299/jsmezairiki.2005.0_243

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記述言語：日本語   出版者・発行元：一般社団法人 日本機械学会  

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記述言語：日本語   出版者・発行元：日本材料学会  

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記述言語：日本語   出版者・発行元：日本材料学会  

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記述言語：日本語   出版者・発行元：養賢堂  

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記述言語：日本語   出版者・発行元：一般社団法人 日本機械学会  

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記述言語：日本語   出版者・発行元：一般社団法人 日本機械学会  

As the bond coating, NiCoCrAlY was low-pressure plasma sprayed on the substrate of SUS304, and zirconia with 8 mass% yittria was electron beam-physical vapor deposited (EB-PVD) on the bond coating as the top coating. The in-plane stress in the top coating was measured by laboratory X-rays and the out-of-plane strain was measured by high energy X-rays from the synchrtron source. Combining the stresses measured by laboratory and synchrotron X-rays, the distributions of the residual stresses were obtained. In the top coating, the in-plane stress was a large compression and out-of-plane stress was compression. The cracking mode of the top coating showed shear compression, and it corresponded to the in-plane stress distribution. Near the interface between the top and the bond coating, the out-of-plane stress changed into a tension.

DOI： 10.1299/jsmemecjo.2004.1.0_249

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記述言語：日本語   出版者・発行元：日本材料学会  

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記述言語：日本語   出版者・発行元：一般社団法人 日本機械学会  

Influence of bond coat interface roughness to the internal residual stress of TBC prepared by thermal spray process was considered. Two kinds of samples to which surface roughness was changed were prepared. One has rough interface and the other has relatively smooth one. The internal residual stress measurement was carried out by using (sin)^2&amp;orv; method with high energy X-rays (72keV) from synchrotron radiation of SPring-8. As for the X-ray diffraction profile, the diffraction peak of a bond coat was also detected, therefore the high energy X-rays had penetrated the ceramic layer. When interface roughness of a bond coat was large, residual stress was compressive, and when that is small, it was tensile. The residual stress is caused by the quenching from the molten droplet during thermal spray process and/or the thermal expansion mismatch between the ceramic top coat and the substrate. The difference of residual stress state was due to the difference in the adhesion strength of a ceramic layer and a bond coat.

DOI： 10.1299/jsmemecjo.2003.1.0_249

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記述言語：英語   出版者・発行元：一般社団法人 日本機械学会  

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記述言語：日本語   出版者・発行元：新潟大学  

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記述言語：日本語   出版者・発行元：新潟大学  

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記述言語：日本語   出版者・発行元：一般社団法人 日本機械学会  

DOI： 10.1299/jsmezairiki.2002.0_741

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記述言語：日本語   出版者・発行元：新潟大学教育人間科学部附属教育実践総合センター  

「情報教育論(情報処理と教育活用)」という授業を、1997年から現在までの5年間にわたって、前期に2コマ(200人)、後期に1コマ(50人)の規模で実施してきた。その後、1999年10月からは「LAN接続できるノート型パソコン(受講者が購入した)」を用いるという授業実践も開始した。こうした授業を実施する中で、特に必要になる事前準備、授業方法・授業運営のあり方、などについて5年間の経験を蓄積してきた。さらに、こうした授業の各学期開始や終了時期には、受講者に対するアンケート調査による授業改善のための検討や分析を継続的に行ってきた。本稿ではこうした「情報教育論」のいくつかのタイプの授業を開始した経過、授業内容や成果と問題点、および今後の課題、などについて報告する。特に、「LAN接続したパソコン(受講者購入も含む)による情報教育」における授業の効果については、講義の学期開始期や終了期に実施したアンケート調査によって、2年間に渡ってその評価を試みたのでその結果を報告する。

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記述言語：日本語   出版者・発行元：日本機械学会  

A high-energy X-ray beam from a synchrotron radiation source, SPring-8,was used to determine the residual stress distribution below the shot-peened surface of a carbon steel plate. By using the monochromatic X-ray beam with three energy levels of 30,60 and 72keV, the stress values were determined by the (sin)^2Ψ method with the side-inclination method (Ψ diffractometer). The stress value was estimated from the slope of the linear approximation of the relation between 2θ and (sin)^2Ψ in the range of (sin)^2Ψ=0 to 0.5. The estimated stress agreed with the distribution of the residual stress measured by removing the surface layer and repeating the X-ray measurement with Cr-Kα radiation. The nonlinearity of the (sin)^2Ψ diagram can be used to estimate the distribution of the residual stress. A new method was proposed to estimate the stress value of the distributed residual stress. The new method was a combination of the side-inclination method and the iso-inclination method (ω diffractometer) to maintain the penetration depth constant. The stress value at a given penetration depth was successfully determined by the new method.

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記述言語：日本語   出版者・発行元：日本機械学会  

A thermal barrier coating is multi-coating system made of a zirconia top coat and a NiCoCrAlY bond coat. To improve thermal barrier coatings, it is indispensable to measure residual stresses and oxidation of the bond coat through the top coat. Since a high energy X-ray has a large penetration depth, diffractions from the bond coat can be measured through the zirconia top coat. In this study, the diffraction profiles from the bond coat were measured through the top coat with the thickness of 0.1 mm by using 72 keV X-ray source. As a result, the 311 diffraction from Ni_3Al is useful for measuring residual stresses in the bond coat. The distribution of the residual stresses in the top coat and the bond coats were measured with Cr-Kα radiations. The residual stresses in the surface layer were released due to cracks, and residual stresses were about 50MPa below the depth of about 50μm. Near the boundary between the top coat and the bond coat, the residual stresses in the top coat increased, whereas the bond coat showed large compressive residual stresses. The compressive residual stresses decreased in the deep layer from the boundary.

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記述言語：日本語   出版者・発行元：日本材料学会  

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記述言語：日本語   出版者・発行元：新潟大学教育人間科学部  

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記述言語：日本語   出版者・発行元：日本機械学会  

Two kinds of thermal barrier coating films with 8 wt% yittria-zirconia were made by atmosphere plasma spraying (APS film) and by low-pressure plasma spraying (LPS film). These films were removed from substrates. The mechanical and X-ray elastic constants of the APS and LPS films were measured by tensile and bending deformation. For the APS film, a lamella structure was formed with solidification of molten zirconia and lamellae were interlaced with each other. Sliding between lamellae is restrained so that the mechanical elastic constants by bending deformation are about the same as that by tensile deformation. For the LPS film, lamellae were piled up regularly and the thickness of the lamellae was thinner than that of the APS film. The mechanical elastic constant of the LPS film measured by bending deformation was lower than that by tensile deformation, because of sliding between lamellae. On the other hand, the X-ray elastic constants of the APS and LPS films were nearly identical, because the X-ray elastic constant was obtained from the strain of the crystalline phase in response to the applied stress.

DOI： 10.1299/kikaia.67.1325

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記述言語：英語   出版者・発行元：公益社団法人 日本材料学会  

The X-ray elastic constants of pressureless sintered &amp;beta;-silicon nitride (Si&lt;sub&gt;3&lt;/sub&gt;N&lt;sub&gt;4&lt;/sub&gt;), were experimentally determined for ten different diffractions by using K&amp;alpha; radiations of Cu, Co, Fe, Cr and V. The X-ray compliances, (1+&lt;i&gt;v&lt;/i&gt;&#039;&lt;sub&gt;x&lt;/sub&gt;)/&lt;i&gt;E&lt;/i&gt;&#039;&lt;sub&gt;x&lt;/sub&gt; and &lt;i&gt;v&lt;/i&gt;&#039;&lt;sub&gt;x&lt;/sub&gt;/&lt;i&gt;E&lt;/i&gt;&#039;&lt;sub&gt;x&lt;/sub&gt; (&lt;i&gt;E&lt;/i&gt;&#039;&lt;sub&gt;&lt;i&gt;x&lt;/i&gt;&lt;/sub&gt;=Young&#039;s modulus, &lt;i&gt;v&lt;/i&gt;&#039;&lt;sub&gt;&lt;i&gt;x&lt;/i&gt;&lt;/sub&gt;=Poisson&#039;s ratio), change as a second power function of cos&lt;sup&gt;2&lt;/sup&gt;&amp;phi; (&amp;phi;=angle between the diffraction plane normal and the &lt;i&gt;c&lt;/i&gt;-axis of hexagonal crystal). Using the simplex method, the elastic constants of single crystals of &amp;beta;-silicon nitride were determined from the measured values of the X-ray compliances on the basis of the average of Voigt and Reuss models and Kr&amp;ouml;ner&#039;s model, combined with the self-consistent analysis of multi-phase materials. The obtained result shows a high stiffness in the &lt;i&gt;c&lt;/i&gt;-direction of hexagonal crystals, but the degree of anisotropy is not so large as the whisker data reported by Hay et al.

DOI： 10.2472/jsms.49.12Appendix_249

Web of Science

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記述言語：日本語   出版者・発行元：東京大学原子力研究総合センター  

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記述言語：日本語   出版者・発行元：日本材料学会  

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記述言語：日本語   出版者・発行元：日本材料学会  

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記述言語：英語   出版者・発行元：一般社団法人日本機械学会  

The residual stress distribution of ground ceramics was determined from the eigen strain distributed near the ground surface. The eigen strain of ground ceramics was tensile, and exponentially decreased with the distance from the surface. The residual stress distribution is given as a superposition of an exponential function of compression and a linear function. It is found that the actual residual stress distribution can be approximated by an exponential function of compression because the magnitude of tensile residual stress is negligibly small compared to the compressive residual stress. In the experiments, the diffraction angle was measured on ground silicon nitride for a wide range of sin^2Ψ using the glancing incidence X-ray diffraction technique. A strong nonlinearity was found in the 2θ-sin^2Ψ diagram at very highΨ-angles. From the analysis of nonlinearity, the residual stress distribution was determined. The residual stress distribution of silicon nitride coincided with the distribution calculated from the eigen strain distribution. Transmission electron microscopy was used to clarify the origin of generation of the residual stress. Both strain contrasts and microcracks were observed below the ground surface ; straight dislocations were also observed within silicon nitride grains near the ground surface.

DOI： 10.1299/jsmea.41.422

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記述言語：日本語   出版者・発行元：日本材料学会  

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記述言語：日本語   出版者・発行元：日本材料学会  

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記述言語：日本語   出版者・発行元：新潟大学  

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記述言語：日本語   出版者・発行元：養賢堂  

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記述言語：日本語   出版者・発行元：ファインセラミックスセンタ-  

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記述言語：日本語   出版者・発行元：日本材料学会  

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記述言語：日本語   出版者・発行元：日本材料学会  

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記述言語：日本語   出版者・発行元：日本材料学会  

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記述言語：日本語   出版者・発行元：日本材料学会  

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記述言語：日本語   出版者・発行元：アグネ技術センター  

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記述言語：日本語   出版者・発行元：新潟大学教育学部  

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記述言語：日本語   出版者・発行元：新潟大学教育学部  

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記述言語：日本語   出版者・発行元：アグネ技術センター  

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記述言語：日本語   出版者・発行元：新潟大学教育学部  

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記述言語：日本語   出版者・発行元：新潟大学教育学部  

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材料、Vol. 57, No.7, pp.674-680 (2008)

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受賞区分：国内学会・会議・シンポジウム等の賞 

Materials Science Research International, Vol. 6-4, pp.249-254 (2000)

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