The Experts below are selected from a list of 161004 Experts worldwide ranked by ideXlab platform
Renzhi Wang - One of the best experts on this subject based on the ideXlab platform.
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Compressive Residual Stress introduced by shot peening
Journal of Materials Processing Technology, 1998Co-Authors: Shengping Wang, Mei Yao, Yongjun Li, Renzhi WangAbstract:The distributions of Residual Stresses of shot peened 20Cr, 30CrMo, 40Cr, GC4, 45 steels and LC9 aluminum alloy over the hardened layer were measured in an X-ray diffraction apparatus using the O and 30° two-point method with step-by-step electrolytical dissolution, and then studied quantitatively. The compressive Residual Stress at the surface, σsrc, the maximum compressive Residual Stress, σmaxrc, the depth of the compressive Residual Stress field (CRSF), Z0, and the average diameter of peening dents D, could be calculated empirically from the metal yield strength, σ0,2, the ultimate tensile strength, σb, and the peening intensity, fA. © 1998 Elsevier Science S.A.
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compressive Residual Stress introduced by shot peening
Journal of Materials Processing Technology, 1998Co-Authors: Shengping Wang, Yongjun Li, Renzhi WangAbstract:Abstract The distributions of Residual Stresses of shot peened 20Cr, 30CrMo, 40Cr, GC4, 45 steels and LC9 aluminum alloy over the hardened layer were measured in an X-ray diffraction apparatus using the 0 and 30° two-point method with step-by-step electrolytical dissolution, and then studied quantitatively. The compressive Residual Stress at the surface, σ s rc , the maximum compressive Residual Stress, σ max rc , the depth of the compressive Residual Stress field (CRSF), Z 0 , and the average diameter of peening dents D , could be calculated empirically from the metal yield strength, σ 0.2 , the ultimate tensile strength, σ b , and the peening intensity, f A .
Shengping Wang - One of the best experts on this subject based on the ideXlab platform.
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Compressive Residual Stress introduced by shot peening
Journal of Materials Processing Technology, 1998Co-Authors: Shengping Wang, Mei Yao, Yongjun Li, Renzhi WangAbstract:The distributions of Residual Stresses of shot peened 20Cr, 30CrMo, 40Cr, GC4, 45 steels and LC9 aluminum alloy over the hardened layer were measured in an X-ray diffraction apparatus using the O and 30° two-point method with step-by-step electrolytical dissolution, and then studied quantitatively. The compressive Residual Stress at the surface, σsrc, the maximum compressive Residual Stress, σmaxrc, the depth of the compressive Residual Stress field (CRSF), Z0, and the average diameter of peening dents D, could be calculated empirically from the metal yield strength, σ0,2, the ultimate tensile strength, σb, and the peening intensity, fA. © 1998 Elsevier Science S.A.
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compressive Residual Stress introduced by shot peening
Journal of Materials Processing Technology, 1998Co-Authors: Shengping Wang, Yongjun Li, Renzhi WangAbstract:Abstract The distributions of Residual Stresses of shot peened 20Cr, 30CrMo, 40Cr, GC4, 45 steels and LC9 aluminum alloy over the hardened layer were measured in an X-ray diffraction apparatus using the 0 and 30° two-point method with step-by-step electrolytical dissolution, and then studied quantitatively. The compressive Residual Stress at the surface, σ s rc , the maximum compressive Residual Stress, σ max rc , the depth of the compressive Residual Stress field (CRSF), Z 0 , and the average diameter of peening dents D , could be calculated empirically from the metal yield strength, σ 0.2 , the ultimate tensile strength, σ b , and the peening intensity, f A .
Y. Murakami - One of the best experts on this subject based on the ideXlab platform.
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mechanism of creation of compressive Residual Stress by shot peening
International Journal of Fatigue, 1998Co-Authors: M. Kobayashi, T. Matsui, Y. MurakamiAbstract:Abstract In order to clarify the mechanism of the creation of compressive Residual Stress by shot peening, a static compression test and a dynamic impact test using a single steel ball against a flat steel plate were carried out. In the static compression test, compression Residual Stress was created near the center of the ball indentation mark. However, in the dynamic impact test, tensile Residual Stress was created near the center of the ball indentation mark and compression Residual Stress was created outside of the indentation. Furthermore, the tensile Residual Stress in the center of the first ball indentation mark changed to compressive Stress as the density of the ball indentations surrounding the first ball indentation mark increased. Therefore, the compressive Residual Stress created by shot peening is considered to be the result of the superposition of Residual Stress produced by surrounding shots.
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Mechanism of creation of compressive Residual Stress by shot peening
International Journal of Fatigue, 1998Co-Authors: M. Kobayashi, T. Matsui, Y. MurakamiAbstract:In order to clarify the mechanism of the creation of compressive Residual Stress by shot peening, a static compression test and a dynamic impact test using a single steel ball against a flat steel plate were carried out. In the static compression test, compression Residual Stress was created near the center of the ball indentation mark. However, in the dynamic impact test, tensile Residual Stress was created near the center of the ball indentation mark and compression Residual Stress was created outside of the indentation. Furthermore, the tensile Residual Stress in the center of the first ball indentation mark changed to compressive Stress as the density of the ball indentations surrounding the first ball indentation mark increased. Therefore, the compressive Residual Stress created by shot peening is considered to be the result of the superposition of Residual Stress produced by surrounding shots. © 1998 Published by Elsevier Science Ltd.
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mechanism of creation of compressive Residual Stress by shot peening
Transactions of the Japan Society of Mechanical Engineers. A, 1997Co-Authors: M. Kobayashi, T. Matsui, Y. MurakamiAbstract:In order to clarify the mechanism of the creation of compressive Residual Stress by shot peening, a static compression test and a dynamic impact test using a single steel ball against a flat steel plate were carried out. In the static compression test, compression Residual Stress was created near the center of the ball indentation mark. However, in the dynamic impact test, tensile Residual Stress was created near the center of the ball indentation mark and compression mark and compression Residual Stress was created outside of the indentation. Furthermore, the tensile Residual Stress in the center of the first ball indentation mark changed to compressive Stress as the density of the ball indentations surrounding the first ball indentation mark increased. Therefore, the compressive Residual Stress created by shot peening is considered to be the result of the superposition of Residual Stress produced by surrounding shots.
Lisa Looney - One of the best experts on this subject based on the ideXlab platform.
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Residual Stress in HVOF thermally sprayed thick deposits
Surface and Coatings Technology, 2004Co-Authors: Joseph Stokes, Lisa LooneyAbstract:Due to the nature of the high velocity oxy-fuel thermal spray process, Residual Stress build up in thick deposits is a significant and a limiting problem. The Residual Stress-state that evolves in a deposit is largely dependent on the thermal conditions to which the system has been subjected, and is a combination of quenching Stresses, which arise during deposition, and cooling Stresses, post-deposition. It follows that precise control of these phenomena is essential, if a thick deposit is to be thermally sprayed. This paper applies an analytical technique to calculate Residual Stress in thermally sprayed deposits based on geometric properties. Residual Stress results for WC-Co (tungsten carbide-cobalt) samples are compared to experimental results (X-ray diffraction and hole-drilling method). A change in deposit Stress-state from tensile to compressive Stress with deposit thickness is analysed in terms of quenching and cooling Stresses. © 2003 Elsevier B.V. All rights reserved.
Alan Iacopi - One of the best experts on this subject based on the ideXlab platform.
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Effect of SiC-on-Si template Residual Stress on GaN Residual Stress and crystal quality
Physica Status Solidi B-basic Solid State Physics, 2016Co-Authors: Jessica Chai, David Massoubre, Glenn M. Walker, Li Wang, Alan IacopiAbstract:The thermal expansion coefficient mismatch between GaN and SiC is lower than between GaN and Si. However it is usually observed that GaN on SiC/Si templates has higher tensile Stress than GaN directly on Si. To provide an insight into the relationship between SiC template Residual Stress and GaN overlayer Residual Stress and crystal quality, we have analyzed the in-plane Residual Stress gradient present in GaN/SiC microstructure arrays of various dimensions and shapes using micro-Raman spectroscopy. It was found that the GaN overlayer Residual Stress is directly proportional to the SiC buffer layer Residual Stress. GaN films with lower Residual Stress also resulted in GaN films with improved crystal quality. Our study shows that the frequently encountered problems of high tensile Stress in GaN films deposited on SiC templates is due to the high tensile Residual Stress in the SiC layers. The poorer GaN crystal quality deposited on SiC templates reported in literature is also likely due to the high tensile Stress in the SiC templates. In order to grow GaN films with sufficient compressive Stress and crystal quality for subsequent device processing, it is crucial to reduce the high tensile Stress present in the SiC templates.
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Effect of SiC‐on‐Si template Residual Stress on GaN Residual Stress and crystal quality
Physica Status Solidi B-basic Solid State Physics, 2016Co-Authors: Jessica Chai, David Massoubre, Glenn M. Walker, Li Wang, Alan IacopiAbstract:The thermal expansion coefficient mismatch between GaN and SiC is lower than between GaN and Si. However it is usually observed that GaN on SiC/Si templates has higher tensile Stress than GaN directly on Si. To provide an insight into the relationship between SiC template Residual Stress and GaN overlayer Residual Stress and crystal quality, we have analyzed the in-plane Residual Stress gradient present in GaN/SiC microstructure arrays of various dimensions and shapes using micro-Raman spectroscopy. It was found that the GaN overlayer Residual Stress is directly proportional to the SiC buffer layer Residual Stress. GaN films with lower Residual Stress also resulted in GaN films with improved crystal quality. Our study shows that the frequently encountered problems of high tensile Stress in GaN films deposited on SiC templates is due to the high tensile Residual Stress in the SiC layers. The poorer GaN crystal quality deposited on SiC templates reported in literature is also likely due to the high tensile Stress in the SiC templates. In order to grow GaN films with sufficient compressive Stress and crystal quality for subsequent device processing, it is crucial to reduce the high tensile Stress present in the SiC templates.
