纳米晶NiTiV记忆合金的超弹性研究  

Study on superelasticity of nanocrystalline NiTiV memory alloys

作　　者：李诗翰 李秋真 郭精远 郝世杰[1] 崔立山[1] LI Shihan;LI Qiuzhen;GUO Jingyuan;HAO Shijie;CUI Lishan(College of New Energy and Materials,China University of Petroleum(Beijing),Beijing 102249,China)

机构地区：[1]中国石油大学(北京)新能源与材料学院,北京102249

出　　处：《功能材料》2024年第12期12016-12020,共5页Journal of Functional Materials

基　　金：国家重点研发计划项目(2023YFC2412600);国家安全学术基金项目(U2130201、U2330105)。

摘　　要：NiTi基记忆合金的超弹温域较窄(<100℃),限制了其应用范围。通过Ni、V元素共掺杂NiTi,采用真空感应熔炼、锻造、大变形拔丝及低温退火制备出纳米晶(NC)Ni_(51)Ti_(49)V_(1)(%原子分数)合金丝材,利用透射电镜(TEM)表征样品的微观组织,万能拉伸试验机表征样品的超弹性。结果表明,NC Ni_(51)Ti_(49)V_(1)合金为等轴纳米晶,平均晶粒尺寸为13 nm;在不同温度下进行拉伸测试,合金在-40~+100℃的宽温域内表现出优异超弹性,超弹温域宽于NC NiTi合金(25~100℃);另外Ni_(51)Ti_(49)V_(1)合金B2→B19′相变的临界应力温度依赖性(dσ/dT)随温度的降低而降低,从5.6 MPa/℃非线性降低至1.8 MPa/℃。NiTi based memory alloys have a narrow super-elastic temperature range(<100℃),which limits their application range.In this paper,nanocrystalline(NC)Ni_(51)Ti_(49)V_(1)(at.%)alloy wire was prepared by Ni-V co-doped NiTi through vacuum induction melting,forging,large deformation wire drawing and low temperature annealing.The microstructure of the sample was characterized by transmission electron microscopy(TEM),and the superelasticity of the sample was characterized by universal tensile testing machine.The results showed that Ni_(51)Ti_(49)V_(1)alloy consists of nanocrystalline with an average grain size of 13 nm.Tensile tests at different temperatures showed that the alloy exhibited excellent superelasticity in a wide temperature range from-40℃to 100℃,and the superelastic temperature range was wider than that of NC NiTi alloy(25-100℃).In addition,the temperature dependence of the critical stress of the B2→B19′transformation(dσ/dT)decreased from 5.6 MPa/℃to 1.8 MPa/℃with decreasing temperature.

关 键 词：NiTiV记忆合金 纳米晶 超弹性 温度依赖性 

分 类 号：TG139.6[一般工业技术—材料科学与工程]