Materials Science Research International最新文献_第2页

Undesirable Effect of Local Cellular Transformation in Microstructurally-Controlled Ni-base Superalloys Subjected to Previous Damage on High Temperature Fatigue Strength and the Prevention : For Recoating and Refurbishment Technology 显微组织控制的ni基高温合金经前期损伤后局部细胞转变对高温疲劳强度的不良影响及涂层修复技术的预防

Materials Science Research International Pub Date : 2003-03-15 DOI: 10.2472/jsms.52.3Appendix_55

M. Okazaki, I. Ohtera, Y. Harada, Kohichi Namba

{"title":"Undesirable Effect of Local Cellular Transformation in Microstructurally-Controlled Ni-base Superalloys Subjected to Previous Damage on High Temperature Fatigue Strength and the Prevention : For Recoating and Refurbishment Technology","authors":"M. Okazaki, I. Ohtera, Y. Harada, Kohichi Namba","doi":"10.2472/jsms.52.3Appendix_55","DOIUrl":"https://doi.org/10.2472/jsms.52.3Appendix_55","url":null,"abstract":"The microstructural change in a single crystal Ni-base superalloy, CMSX-4, was studied, in order to get basic understandings on the problems that might be serious on the process of repair and recoating of hot section components for advanced gas turbines. It was shown that a cellular γ/γ' microstructure was nucleated, when the material was subjected to damage associated with local plastic straining, followed by the re-heat treatments for damage recovery. Once the cellular microstructure was nucleated inside the material, the fatigue strength was remarkably reduced, hence the cellular γ/γ' microstructure might be a very serious hurdle to be solved. Special efforts were made to explore the method to reduce and prevent the unfavorable effect due to the cellular microstructure and to detect it nondestructively. The experiments indicated that the application of the surface modification technique, or protective metallic coating, on the superalloys, was found to be a possible method. It was also indicated indirectly that the control of parent alloy composition could be important to reduce the harmful effects.","PeriodicalId":377759,"journal":{"name":"Materials Science Research International","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122779458","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Effect of Polarization on Deformation and Fracture of Tetragonal PZT( Materials Evaluation by X-ray and Neutron Diffractions) 极化对方形PZT变形和断裂的影响(x射线和中子衍射评价材料)

Materials Science Research International Pub Date : 2002-12-15 DOI: 10.2472/JSMS.51.12APPENDIX_213

K. Shirakihara, Keisuke Tanaka, Y. Akiniwa

{"title":"Effect of Polarization on Deformation and Fracture of Tetragonal PZT( Materials Evaluation by X-ray and Neutron Diffractions)","authors":"K. Shirakihara, Keisuke Tanaka, Y. Akiniwa","doi":"10.2472/JSMS.51.12APPENDIX_213","DOIUrl":"https://doi.org/10.2472/JSMS.51.12APPENDIX_213","url":null,"abstract":"Four-point bending tests were conducted with smooth specimens of poled and non-poled lead zirconate titanate (PZT) ceramics with a tetragonal structure. The specimens poled in the longitudinal, transverse and short-transverse directions were called PL, PT and PS specimens, respectively. The non-poled specimens were called NP specimens. The true stress-strain relation showed nonlinearity and was different between tension and compression. The nonlinearity of the stress and strain relation resulted from domain switching induced by external loading, and the degree of nonlinearity increased with easiness of domain switching under bending. The fracture strength expressed in terms of the nominal and true stresses followed the Weibull distribution. The shape parameter took a large value around 18 to 22 for PT and PS specimens, while it was the smallest around 7 to 8 for PL specimens. NP specimens took values in between. The mean strength was the largest for NP specimen and was the lowest for PL specimen. Domain switching during loading will relieve local stress concentrations of defects within the material, thus increases the strength and the shape parameter. The change in intensity ratio of the 002 to 200 diffractions can be used to assess the degree of domain switching caused by external straining.","PeriodicalId":377759,"journal":{"name":"Materials Science Research International","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116527439","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

X-Ray Evaluation of Pulse-Plated Crack-Free Cr Layer( Materials Evaluation by X-ray and Neutron Diffractions) 脉冲镀无裂纹Cr层的x射线评价(用x射线和中子衍射评价材料)

Materials Science Research International Pub Date : 2002-12-15 DOI: 10.2472/JSMS.51.12APPENDIX_199

Yuichi Kobayashi, J. Nagasawa, Kazuo Watanabe, T. Sasaki, Y. Hirose

引用次数: 0

Nickel-Catalyzed Carbonization of Lignocresol to Produce Crystallized Carbon Usable for Electromagnetic Shielding 镍催化木酚炭化制备可用于电磁屏蔽的结晶碳

Materials Science Research International Pub Date : 2002-12-15 DOI: 10.2472/JSMS.51.12APPENDIX_249

Xiao-Shui Wang, Tsutomu Suzuki, M. Funaoka, Yoshihiko Mitsuoka, Tetsuo Yamada, S. Hosoya

引用次数: 5

Effect of Plasma Protection Net on Crystal Orientation and Residual Stress in Sputtered Gallium Nitride Films( Materials Evaluation by X-ray and Neutron Diffractions) 等离子体防护网对溅射氮化镓薄膜晶体取向和残余应力的影响(x射线和中子衍射材料评价)

Materials Science Research International Pub Date : 2002-12-15 DOI: 10.2472/JSMS.51.12APPENDIX_187

K. Kusaka, K. Furutani, T. Kikuma, T. Hanabusa, K. Tominaga

{"title":"Effect of Plasma Protection Net on Crystal Orientation and Residual Stress in Sputtered Gallium Nitride Films( Materials Evaluation by X-ray and Neutron Diffractions)","authors":"K. Kusaka, K. Furutani, T. Kikuma, T. Hanabusa, K. Tominaga","doi":"10.2472/JSMS.51.12APPENDIX_187","DOIUrl":"https://doi.org/10.2472/JSMS.51.12APPENDIX_187","url":null,"abstract":"X-ray diffraction was carried out in order to investigate crystal orientation and residual stress in gallium nitride (GaN) films deposited on a fused quartz substrate by radio frequency (RF) planar magnetron sputtering with a net to protect against plasma exposure. GaN films were deposited at constant gas pressure, constant input power, and various substrate temperatures. The following results were obtained: (1) GaN film of good crystal orientation can be deposited by RF sputtering; (2) in all films deposited at high substrate temperature, the c-axes of GaN crystals were oriented normal to the substrate suffice; (3) crystal orientation was good in films deposited at high substrate temperature Ts > 573 K, but film deposited at Ts = 873 K peeled from the substrate; (4) good crystal orientation was attained in films deposited by sputtering with the fine mesh to protect against plasma exposure; (5) compressive residual stress was found in film deposited at low Ts below 573 K; (6) compressive residual stress was found in films deposited by RF sputtering with the plasma protection net.","PeriodicalId":377759,"journal":{"name":"Materials Science Research International","volume":"105 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116033601","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Mechanism of Magnetic Domain Refinement on Grain-Oriented Silicon Steel by Laser Irradiation( Materials Evaluation by X-ray and Neutron Diffractions) 激光辐照晶粒取向硅钢磁畴细化机理(x射线和中子衍射材料评价)

Materials Science Research International Pub Date : 2002-12-15 DOI: 10.2472/JSMS.51.12APPENDIX_207

H. Suzuki, K. Akita, H. Misawa, M. Imafuku

{"title":"Mechanism of Magnetic Domain Refinement on Grain-Oriented Silicon Steel by Laser Irradiation( Materials Evaluation by X-ray and Neutron Diffractions)","authors":"H. Suzuki, K. Akita, H. Misawa, M. Imafuku","doi":"10.2472/JSMS.51.12APPENDIX_207","DOIUrl":"https://doi.org/10.2472/JSMS.51.12APPENDIX_207","url":null,"abstract":"The residual stress distributions near the laser-irradiated line in a crystal grain of an electrical steel sheet were measured by the X-ray stress measurement method for a single crystal, in order to clarify the mechanism of the magnetic domain refinement which can be applied to reduce the core losses. A specimen containing only one grain was cut from a grain-oriented silicon steel, and was irradiated with a laser. The distributions of the residual stresses and those of the half value width (HVW) of the diffraction profile, which indicates the plastic strain level near the laser-irradiated line, were measured before and after the stress-relief annealing, and their magnetic domain structures were observed. Before annealing, the HVW was increased near the laser-irradiated line, since the local plastic deformation was induced by the peening effect of the laser irradiation and the process of melting, cooling, and contraction after the laser irradiation. Therefore, the tensile residual stresses were induced near the laser-irradiated line. Next, the magnetic domains were refined more than they were before the laser irradiation. After annealing, the HVW was constant at the initial value, and the residual stresses were relieved. The magnetic domain then returned to its original width. Therefore, it was confirmed that the magnetic domain was refined due to the residual stress induced by the laser irradiation.","PeriodicalId":377759,"journal":{"name":"Materials Science Research International","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129482039","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Regularity of Strain Distribution in Short-Fiber/Whisker Reinforced Composites 短纤维/晶须增强复合材料应变分布规律研究

Materials Science Research International Pub Date : 2002-12-15 DOI: 10.2472/JSMS.51.12APPENDIX_219

Xiaoyu Liu, Wei Wu, N. Liang

引用次数: 0

Tunneling Algorithm Applied to Reliability Analysis of Laminated Composite Plate( Reliability Engineering in Materials and Structures) 隧道算法在复合材料层合板可靠性分析中的应用(材料与结构可靠性工程)

Materials Science Research International Pub Date : 2002-09-15 DOI: 10.2472/JSMS.51.9APPENDIX_93

N. Kogiso, S. Nakagawa, Y. Murotsu

{"title":"Tunneling Algorithm Applied to Reliability Analysis of Laminated Composite Plate( Reliability Engineering in Materials and Structures)","authors":"N. Kogiso, S. Nakagawa, Y. Murotsu","doi":"10.2472/JSMS.51.9APPENDIX_93","DOIUrl":"https://doi.org/10.2472/JSMS.51.9APPENDIX_93","url":null,"abstract":"In this study, the tunneling algorithm is applied to the first order reliability method (FORM) to find a global design point. In the FORM, the structural reliability is evaluated as the minimum distance from the origin to the limit state surface in the standard normal distribution space. Therefore, the FORM is formulated as a nonlinear optimization problem. However, it is difficult to find the design point, when the limit state surface has several local minimum points such as a case of the laminated composite plate subject to the first ply failure. In general, the original tunneling method is not worked well for the constraint problem. In this study, a new tunneling function suitable for the FORM is proposed to find the other design point which has a lower objective function value and satisfies the equality constraint. In the tunneling function, the limit state function is treated as a kind of a penalty term with a pole. Through the reliability analysis of a laminated composite plate subject to in-plane loads, the efficiency of the proposed tunneling function is demonstrated. Also, the selection of the penalty parameter is suggested.","PeriodicalId":377759,"journal":{"name":"Materials Science Research International","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126561858","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Probabilistic Strength Estimation for Ceramic-Metal Joints with Various Interlayer Thicknesses( Reliability Engineering in Materials and Structures) 不同夹层厚度陶瓷-金属连接的概率强度估计(材料与结构可靠性工程)

Materials Science Research International Pub Date : 2002-09-15 DOI: 10.2472/JSMS.51.9APPENDIX_109

Manabu Takahashi, N. Okabe, Xia Zhu, Ken-ichiro Kagawa

{"title":"Probabilistic Strength Estimation for Ceramic-Metal Joints with Various Interlayer Thicknesses( Reliability Engineering in Materials and Structures)","authors":"Manabu Takahashi, N. Okabe, Xia Zhu, Ken-ichiro Kagawa","doi":"10.2472/JSMS.51.9APPENDIX_109","DOIUrl":"https://doi.org/10.2472/JSMS.51.9APPENDIX_109","url":null,"abstract":"Residual stress generated by thermal expansion coefficient mismatch between ceramic and metal is an important problem affecting the strength of ceramic-metal joints. An interlayer, which is a ductile metal, is often inserted between ceramic and metal in order to relax this residual stress. In this study, the residual stress produced in the joint-cooling process is analyzed and 4-point bending tests are carried out. From the viewpoint of experimental observations and fracture mechanics, the effects of interlayer thickness on joint strength in ceramic/metal joints are discussed considering the superimposed stress distribution of the residual stress and the bending stress. Joint strength is then estimated based on fracture mechanics and fracture probability considering the superimposed stress, crack size and position of pre-existing defects in the ceramics. The optimum interlayer thickness for the present specimen is identified, and the estimation method is extended to the analysis of generic joint strength using normalized strength of ceramic by expressing joint strength in terms of normalized strength considering the scatter of joint strength and the effective volume.","PeriodicalId":377759,"journal":{"name":"Materials Science Research International","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124813825","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Markov Process Analysis for the Strength of Ceramic Matrix Composites Reinforced with Continuous Fibers( Reliability Engineering in Materials and Structures) 连续纤维增强陶瓷基复合材料强度的马尔可夫过程分析(材料与结构可靠性工程)

Materials Science Research International Pub Date : 2002-09-15 DOI: 10.2472/JSMS.51.9APPENDIX_87

K. Goda

{"title":"Markov Process Analysis for the Strength of Ceramic Matrix Composites Reinforced with Continuous Fibers( Reliability Engineering in Materials and Structures)","authors":"K. Goda","doi":"10.2472/JSMS.51.9APPENDIX_87","DOIUrl":"https://doi.org/10.2472/JSMS.51.9APPENDIX_87","url":null,"abstract":"A stochastic model for predicting the strength and reliability of unidirectional fiber-reinforced ceramic matrix composites is proposed, in order to find theoretically statistical properties in strength of the composites, composed of constituents with large variations in strength. In the proposed model, mechanical behaviors of the composites follows the Curtin's assumptions, of which validity was examined by a FEM analysis. The proposed model is based on a Markov process, in which it is assumed that a damage state in the composite is developed with each fiber breakage. When the Weibull distribution is used as a strength distribution of the fiber, the probability of being in each state is analytically solved as a function of stress. The expected value and variance in the composite stress were then estimated from the probabilities of being in states. Furthermore, the maximum stress of the expected value, i.e. the strength, is predicted together with the coefficient of variation. The results showed that, even if broken fibers are imperfectly recovered in stress along the fiber-axis from the breakage points, the composite exhibits a higher strength and reliability than that of a dry bundle. Finally, it is concluded that stress recovery in broken fibers is a significant mechanism to determine the strength and reliability of the composites.","PeriodicalId":377759,"journal":{"name":"Materials Science Research International","volume":"87 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127890941","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2