钇对NiMnSn高温记忆合金相变和力学性能的影响  

Effect of Y on Martensitic Transformation and Mechanical Properties of NiMnSn High Temperature Shape Memory Alloy

作　　者：李剋蒙 陈枫[1] 佟运祥 李莉[1] 郑玉峰[2] 

机构地区：[1]哈尔滨工程大学,黑龙江哈尔滨150001 [2]北京大学,北京100871

出　　处：《稀有金属材料与工程》2013年第S2期370-374,共5页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(51101040)

摘　　要：采用光学显微镜、SEM、DSC、压缩试验等方法,研究了添加稀土Y对Ni50Mn42Sn8高温形状记忆合金的显微组织、马氏体相变、力学性能和形状记忆效应的影响。结果表明:稀土Y的加入明显细化合金晶粒,同时引入了富稀土第二相;高温热处理能够消除铸态合金存在的成分不均匀性,呈现一步热弹性马氏体相变;随Y含量的增加,NiMnSn合金的相变温度升高;压缩试验表明,添加Y可显著提高Ni50Mn42Sn8合金的力学性能,同时保持一定的形状记忆效应。The effects of rare earth element Y addition on the microstructure,martensitic transformation,room temperature mechanical properties and shape memory effect of Ni50Mn42Sn8 high temperature shape memory alloy were studied by means of optical microscope,SEM,DSC,and compression tests etc.The results show that the doping of Y considerably refines the grains,and the microstructure of NiMnSn alloys consists of the matrix and Y-riched second phase which distributes along the grain boundary.High temperature annealing leads to the chemical homogeneity which makes the alloys undergo a single-stage thermalelastic martensitic transformation and reverse transformation.With the increase of Y content,all transformation temperatures are shifted to high temperature.Compression tests indicate that,a proper addition of Y remarkably improves the mechanical properties,Meanwhile,a given magnitude of shape memory effect is obtained.

关 键 词：Ni-Mn-Sn合金 高温形状记忆合金 稀土 马氏体相变 

分 类 号：TG139.6[一般工业技术—材料科学与工程]