Investigation on Texture Evolution Mechanism of NiTiFe Shape Memory Alloy Under Plane Strain Compression

Abstract

Texture evolution of NiTiFe shape memory alloy (SMA) is investigated during plane strain compression based on crystal plasticity finite element method (CPFEM) and electron back-scatter diffraction (EBSD) experiment. The deformation textures of NiTiFe SMA are not influenced very considerably after experiencing recrystalline annealing at 600 °C for 1 h. Based on the results of CPFEM, the main activated slip systems of NiTiFe SMA are 〈100〉/{110} and 〈111〉/{110} ones during plane strain compression. According to the relationship between texture components and activated slip systems put forward in this study, 〈110〉 direction would rotate to rolling direction, whereas 〈100〉 and 〈111〉 directions would rotate to normal direction. These rotations contribute to the formation of γ-fibre texture and α-fibre texture in NiTiFe SMA. The deformation texture components predicted by CPFEM and determined by EBSD were compared with each other in detail. Due to the startup of the pencil glide and multiple slip in the refined microstructure, there are some differences between texture components predicted by CPFEM and texture components determined by EBSD. The deformation heterogeneity is discussed in terms of rotation angle at each integration point in the study.