Improving the Mechanical and Tribological Properties of NiTi Alloys by Combining Cryo-Rolling and Post-Annealing

• 作者: Yong Wen Yan-Fei Wang Hao Ran Wei Wei Jun-Ming Zhang Chong-Xiang Huang
• 来源期刊: 金属学报（英文版）
• 年，卷（期）: 2022,（2）
• 页码范围: 317-325
• 页数: 9页
• 语种: 英文

摘要

By combining cryo-rolling and post-annealing treatments,the nanostructured NiTi alloy is produced.A differential scanning calorimetry measurement was used to test the effect of the preparation process on phase transformation.The cryo-rolling changes the tensile fracture of NiTi alloy to a ductile manner.Interestingly,the recovered structure exhibits significant strength improvement,while the tensile plasticity is still comparable to that of the coarse-grained structure.This optimized mechanical performance is due to the strengthening effect of refined microstructure and the high work hardening capability rendered by moderate dislocation density.Ball-on-plate reciprocating dry-sliding wear test reveals that the nanostructured NiTi alloy also has enhanced wear resistance,which is primarily ascribed to the high content of residue martensite formed during cryo-rolling.These results provide an effective route to optimize the mechanical and wear properties of NiTi alloys.