中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 30 No. 5 May 2020 |
（1. College of Mechanical and Electrical Engineering, Harbin Engineering University, Harbin 150001, China;
2. College of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin 150001, China）
Abstract:Based on the channel die compression, NiTiFe shape memory alloy (SMA) was subjected to plane strain compression. Mechanically-induced martensite transformation, nanocrystalline and amorphous phase can be observed in the case of large plastic strain. Mechanically-induced martensite transformation is obviously different from the conventional stress-induced martensite transformation. The former generally occurs after dislocation slip, whereas the latter arises prior to dislocation slip. The occurrence of B19'''' martensite phase contributes to accommodating subsequent plastic deformation of NiTiFe SMA. Mechanically-induced B19'''' martensite is partially stabilized due to the existence of local high stress field and consequently it is unable to be reverted to B2 austenite phase during unloading.
Key words: shape memory alloy; NiTiFe alloy; plastic deformation; martensitic transformation; microstructure
