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 

机构地区：[1]School of Aeronautics and Astronautics,Sichuan University,Chengdu 610065,China

出　　处：《Acta Metallurgica Sinica(English Letters)》2022年第2期317-325,共9页金属学报（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(No.51931003);the China Postdoctoral Science Foundation(No.2020M680223)。

摘　　要：By combining cryo-rolling and post-annealing treatments,the nanostructured NiTi alloy is produced.A diff erential scanning calorimetry measurement was used to test the eff ect 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 signifi cant 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 eff ect of refi ned 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 eff ective route to optimize the mechanical and wear properties of NiTi alloys.

关 键 词：NiTi alloy Phase transformation Strength and ductility Wear resistance Cryogenic rolling 

分 类 号：TG146.15[一般工业技术—材料科学与工程] TG156.2[金属学及工艺—金属材料] TG335[金属学及工艺—金属学]