Intrinsic two-way shape memory effect in a Ni-Mn-Sn metamagnetic shape memory microwire  

出　　处：《Journal of Materials Science & Technology》2020年第10期44-48,共5页材料科学技术（英文版）

基　　金：the National Natural Science Foundation of China(Nos.51731005,51822102 and 51527801);the Fundamental Research Funds for the Central Universities(grant No.FRF-TP-18-008C1);Use of the Advanced Photon Source was supported by the U.S.Department of Energy,Office of Science,Office of Basic Energy Science,under Contract No.DE-AC02-06CH11357.

摘　　要：An intrinsic two-way shape memory effect with a fully recoverable strain of 1.0%was achieved in an as-prepared Ni50Mn37.5Sn12.5 metamagnetic shape memory microwire fabricated by Taylor-Ulitovsky method.This two-way shape memory effect is mainly owing to the internal stress caused by the retained martensite in austenite matrix,as revealed by transmission electron microscopy observations and highenergy X-ray diffraction experiments.After superelastic training for 30 loading/unloading cycles at room temperature,the amount of retained martensite increased and the recoverable strain of two-way shape memory effect increased significantly to 2.2%.Furthermore,a giant recoverable strain of 11.2%was attained under a bias stress of 300 MPa in the trained microwire.These properties confer this microwire great potential for micro-actuation applications.

关 键 词：Metamagnetic shape memory alloys Two-way shape memory effect MICROWIRE Recoverable strain MICROSTRUCTURE 

分 类 号：TG139.6[一般工业技术—材料科学与工程]