In-situ synchrotron high energy X-ray diffraction study of spontaneous reorientation of R phase upon cooling in nanocrystalline Ti_(50)Ni_(45.5)Fe_(4.5)alloy

作     者：Zhi-Yuan Ma Yu-Xuan Chen Yang Ren Kai-Yuan Yu Da-Qiang Jiang Yi-Nong Liu Li-Shan Cui Zhi-Yuan Ma;Yu-Xuan Chen;Yang Ren;Kai-Yuan Yu;Da-Qiang Jiang;Yi-Nong Liu;Li-Shan Cui

作者机构：Department of Materials Science and EngineeringChina University of Petroleum(Beijing)Beijing 102249China Department of PhysicsCity University of Hong KongHong Kong 999077China Centre for Neutron ScatteringCity University of Hong KongHong Kong 999077China Department of Mechanical EngineeringThe University of Western AustraliaPerthWA 6009Australia 

出 版 物：《Rare Metals》 (稀有金属（英文版）)

年 卷 期：2022年第41卷第6期

页      面：1948-1954页

核心收录：

学科分类：0806[工学-冶金工程] 08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 0703[理学-化学] 

基　　金：financially supported by the National Natural Science Foundation of China (Nos.51731010, 51831006,51871241,51971243 and 91963112) Australian Research Council (No.DP190102990) 

主　　题：TiNiFe Martensitic transformation R phase reorientation Synchrotron diffraction Nanocrystalline material 

摘      要：This study investigated a peculiar phenomenon of self-reorientation of thermally formed R phase in nanocrystalline Ti_(50)Ni_(45.5)Fe_(4.5)by means of in-situ syn-chrotron high energy X-ray diffraction(HE-XRD).Two samples with different average grain sizes of 40 and 90 nm were investigated.R phase in the 40-nm grain size sample was found to self-reorient gradually upon cooling,whereas the same phenomenon did not occur in the 90-nm grain size *** self-reorientation process is attributed to the development and evolution of an internal stress anisotropy caused by the second order continuous lattice distortion of R phase upon further cooling in the small nanograined matrix,which lacks the self-accommodation mechanism for internal stress cancellation.