New developments on displacive phase transformations

位移相变的新进展

• 批准号: 09242103
• 负责人: OTSUKA Kazuhiro
• 金额: $ 58.18万
• 依托单位: University of Tsukuba
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research on Priority Areas
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-09242103/
• 关键词: displacive phase transformation; martensitic transformation; pretransformation phenomena; lattice defects; kinetics of transformation; shape-memory thin films; nano-particles; lattice softening; ゴム弾性的挙動; 形状記憶効果; Ti-Ni薄膜

For the five themes studied in this group, the abstracts of the results are described for each theme.(a) The mechanism of 1st order displacive transformations : The elastic constants of Ti-Ni alloy system (Ti-Ni, Ti-Ni-Cu, Ti-Ni-Fe) were measured systematically by utilizing "the parallelepiped resonance method" prior to the martensitic transformations. As a result, close relations were found to exist between the three kinds of martensitic transformations and the temperature dependence of elastic constants (c', c_<44>), and elastic anusotropy (A ≡ c_<44>/c').(b) The interaction of lattice defects with 1st order displacive transformation : The all aspects of the long-standing problem of "rubber-like behavior" was consistently explained by introducing "SC-SRO (Symmetry-Conforming Short Range Order) principle" (Nature, 1997) with respect to point defects upon displacive transformation. Furthermore, other new phenomena such as "microstructure memory" and "two-way shape memory" effects were … More found based on this principle (Phys.Rev.Lett., 2000).(c) New approach to thermodynamics of 1st order displacive transformations : For Kakeshita's theory, who treated athermal and isothermal martensitic transformations in a unified manner, systematic experiments were carried out. Thus the theory was justified by showing that an isothermal transformation will change into athermal one under magnetic field, and an athermal one into an isothermal one under hydrostatic pressure etc.(d) 1st order displacive transformations in thin films : The structures of Ti-Ni thin films produced by sputter-deposition technique were systematically studied by TEM.As a result, five precipitation states were found to exist as a function of composition and aging temperature.(e) 1st order displacive transformations in nanometer-sized alloy paricles : The martensitic transformations of nano-particles of Au-Cd and Fe-Ni alloys were observed in-situ by TEM, by using a newly developed apparatus directly connected TEM and vacuum evaporation chamber. As a result, the transformations temperatures of the alloys were found to decrease greatly, but the cause was found not to be explained by the previous theory. Less

对于该组中研究的五个主题，为每个主题描述了结果的摘要。（a）一阶移位转换的机制：Ti-Ni合金系统的弹性常数（Ti-Ni，Ti-Ni-Cu，Ti-ni-Fe）是通过系统地测量了“通过平行校准的Martonance dectressication”的“ Martonance dectressities”。结果，发现了三种马氏体转变与弹性常数（c'，c_ <44>）的温度依赖性之间存在密切关系“ SC-SRO（对称性构成短距离顺序）原理”（自然，1997年），就位移转换时的点缺陷而言。 Furthermore, other new phenomena such as "microstructure memory" and "two-way shape memory" effects were … More found based on this principle (Phys.Rev.Lett., 2000).(c) New approach to thermodynamics of 1st order displacive transformations: For Kakeshita's theory, who treated athermal and isothermal martensitic transformations in a unified manner, systematic experiments were carried out.该理论是通过表明在磁场下变成静等性转换的理论是合理的，而在静水压力等下，将其变成一个等温场。（d）薄膜中的一阶移位转换：Ti-ni薄膜的结构是由Spipter-Depositive Technology所产生的Ti-Ni薄膜的结构。温度。（E）通过使用新开发的设备直接连接的TEM和真空经济室观察到纳米尺寸合金片剂中的一阶移位转换：Au-CD和Fe-Ni合金的马塞西质转换在Au-CD和Fe-Ni合金中的马氏体转化。结果，发现合金的转化温度大大降低，但由于先前的理论没有发现原因。较少的

项目成果

X.Ren et al.: "The Role of the Softening Elastic Constant c_<44> in Martensitic Transformation" Script.Mater.(in press). (1998)

X.Ren 等人：“软化弹性常数 c_<44> 在马氏体转变中的作用”Script.Mater.（​​出版中）。

Y.Asaka et al.: "TEM and Electron Diffraction on Structure and Phase Transformation of Nanometer-sized Fe-Ni Alloy Particles" The Third Pacific Rim International conference on Advanced Materials and Processing(PRICM 3). 1467-1472 (1998)

Y.Asaka 等人：“TEM 和电子衍射对纳米铁镍合金颗粒结构和相变的影响”第三届环太平洋先进材料与加工国际会议（PRICM 3）。

T.Tadaki et al.: "Structure and Phase Transformation of Nanometer-sized Particles of Alloys Examined by TEM and Electron Diffraction" Proceedings of the XVII Conference Applied CRYSTALLOGRAPHY. 270-277 (1998)

T.Tadaki 等人：“通过 TEM 和电子衍射检查合金纳米尺寸颗粒的结构和相变”第十七届应用晶体学会议论文集。

A.Gyobu et al.: "Mechanical Properties of Sputter-Deposited Amorphous Ti-Ni Alloys" Proc.of PRICM 3 The Minerals, Metals and Materials Society. 2719-2724 (1998)

A.Gyobu 等人：“溅射沉积非晶态 Ti-Ni 合金的机械性能”Proc.of PRICM 3 矿物、金属和材料协会。

K.Otsuka, C.M.Wayman: "Shape Memory Materials"Cambridge University Press. 284 (1998)

K.Otsuka、C.M.Wayman：“形状记忆材料”剑桥大学出版社。