Scripta Materialia 284 (2026) 117477

Keywords:NiTi shape memory alloy, Dislocation, Austenitic transformation, Lattice distortion

Dislocation is inevitable during phase transformation of NiTi shape memory alloys, and its presence typically  exerts detrimental effects on the performance of materials in most cases. Therefore, reducing the detrimental  effects of dislocation and even utilizing it to promote phase transformation is an important challenge. In this  study, in-situ electron backscattering diffraction (EBSD) is employed to investigate the effects of dislocation on  the austenitic transformation. The results indicate that a higher density of dislocation induces greater lattice  distortion and higher free energy in martensite, thereby facilitating its transformation to austenite upon heating.  This discovery presents new avenues for effectively mitigating the detrimental effects of dislocation in phase  transformation.

Xiangyu Li, Xiaoxian Zhang, Yanju Liu, Jinsong Leng

Promotion of austenitic transformation by dislocation in NiTi shape memory alloys.pdf