物理学报2012，Vol.61Issue(2)：430-435,6.
内应力对Mn_2NiGa铁磁形状记忆合金的结构、相变和磁性能的影响
Effect of internal stress on sructure,martensitic transformation and magnetic properties of ferromagnetic shape memory alloy Mn_2NiGa
摘要
Abstract
The structures,the martensitic transformations and the magnetic properties of ferromagnetic shape memory alloy Mn_2NiGa with the loading and the unloading of the external compressive stress are investigated.The plastic deformation occurring during the stressing causes a high level of dislocation defects existing in the sample.The residual internal stress results in a significant increase of the reversed transformation temperature.The threshold value of compressive pressure for causing the completely martensitic transformation at room temperature is identified to be 1.0 GPa based on the experimental measurements of XRD and magnetic coercivity. The coercivity of the martensitic phase increases from 50 Oe to 350 Oe due to the application of the external stress up to 2.0 GPa.It is also observed that the reversed martensitic transformation occurrs,when the sample is treated by heating up to about 730 K.This is attributed to the elimination of the dislocation by the annealing effect.Such a high reverse martensitic transformation temperature allows the measurement of the Curie temperature of martensitic phase and the obtained value is 530 K.关键词
铁磁形状记忆合金/Mn_2NiG_a/残余内应力/马氏体相变Key words
ferromagnetic shape memory alloys/Mn_2NiGa/residual internal stress/martensitic transformation分类
矿业与冶金引用本文复制引用
宋瑞宁,朱伟,刘恩克,李贵江,陈京兰,王文洪,李祥,吴光恒..内应力对Mn_2NiGa铁磁形状记忆合金的结构、相变和磁性能的影响[J].物理学报,2012,61(2):430-435,6.基金项目
国家自然科学基金 （）
国家重点基础研究发展计划（2010CB833102）资助的课题~~ （）
