基于相场模拟的应力辅助时效的NiTi形状记忆合金功能性能研究  

PHASE-FIELD SIMULATION ON THE FUNCTIONAL PROPERTIES OF STRESS-ASSISTED AGING NiTi SHAPE MEMORY ALLOYS

作　　者：徐波[1,2] 于超 王宠[1,2] 阚前华[3,4] 王清远 康国政[3,4] Xu Bo;Yu Chao;Wang Chong;Kan Qianhua;Wang Qingyuan;Kang Guozheng(Failure Mechanics and Engineering Disaster Prevention Key Laboratory of Sichuan Province,Sichuan University,Chengdu 610065,China;Key Laboratory of Deep Underground Science and Engineering,Ministry of Education,Sichuan University,Chengdu 610065,China;Applied Mechanics and Structure Safety Key Laboratory of Sichuan Province,School of Mechanics and Aerospace Engineering,Southwest Jiaotong University,Chengdu 610031,China;State Key Laboratory of Rail Transit Vehicle System,Southwest Jiaotong University,Chengdu 610031,China)

机构地区：[1]四川大学灾变力学与工程防灾四川省重点实验室,成都610065 [2]四川大学深地科学与工程教育部重点实验室,成都610065 [3]西南交通大学力学与航空航天学院,应用力学与结构安全四川省重点实验室,成都610031 [4]西南交通大学轨道交通运载系统全国重点实验室,成都610031

出　　处：《力学学报》2024年第12期3507-3520,共14页Chinese Journal of Theoretical and Applied Mechanics

基　　金：四川省科技计划(2024NSFSC1346);国家自然科学基金(12322203)资助项目。

摘　　要：通过改进的耦合沉淀相析出和马氏体相变的相场模型模拟了应力辅助时效的NiTi单晶的超弹性、弹卡效应、单程形状记忆效应和应力辅助双程形状记忆效应,讨论了单一取向Ni_(4)Ti_(3)沉淀相对功能性能的影响以及背后的微观机理.模拟结果显示,由于单一取向Ni_(4)Ti_(3)沉淀相的强几何约束,超弹性过程和应力辅助双程形状记忆过程中的马氏体相变并不以马氏体条带快速扩宽的方式进行,而是以大量针状马氏体的形核与生长来实现,马氏体逆相变则以大量针状马氏体的缩减和消失来实现.含单一取向Ni_(4)Ti_(3)沉淀相的单晶系统具有优良的弹卡效应.对于单程形状记忆效应,含单一取向Ni_(4)Ti_(3)沉淀相的单晶系统在温度诱发马氏体相变过程中形成的孪晶面均与沉淀相惯习面平行,单一取向和两种取向的Ni_(4)Ti_(3)沉淀相对马氏体重取向的约束不同,对温度诱发马氏体逆相变的约束也不同,导致二者对应的应力-应变-温度曲线的差异.文章将为理解Ni_(4)Ti_(3)沉淀相对Ni Ti合金功能性能的影响提供见解,并为调控合金的马氏体相变、功能和力学性能提供参考.In this work,an improved phase field model coupling precipitation and martensitic transformation(MT)was used to simulate the superelasticity,elastocaloric effect,one-way shape memory effect(OWSME)and stress-assisted two-way shape memory effect(SATWSME)of the stress-assisted aging NiTi single crystal.The influence of singleorientated Ni_(4)Ti_(3)precipitates on the functional properties and the underlying microscopic mechanism were revealed.The simulation results show that due to the strong geometric constraints of single-oriented Ni_(4)Ti_(3)precipitates,the MT in the superelastic or SATWSME process is not realized by the rapid widening of martensitic bands,but by the nucleation and growth of a large number of needlelike martensite phases,and the reverse MT is achieved by the reduction and disappearance of a large number of needlelike martensite phases.The single-crystal system containing single-oriented Ni_(4)Ti_(3)precipitates shows an excellent elastocaloric effect.For the OWSME,in the single-crystal system with singleoriented Ni_(4)Ti_(3)precipitates,the twinned interfaces formed during the temperature-induced MT are parallel to the inertial plane of the Ni_(4)Ti_(3)precipitates;the constraints of the single-orientated and different-orientated Ni_(4)Ti_(3)precipitates on the martensitic reorientation are different,and those on the temperature-induced reverse MT are also different,resulting in the difference in the stress-strain-temperature curves of the two cases.This work will provide insights for understanding the effect of Ni_(4)Ti_(3)precipitates on the functional properties of NiTi alloys,and provide references for regulating the MT,functional and mechanical properties of such alloys.

关 键 词：NITI形状记忆合金 Ni_(4)Ti_(3)沉淀相 相场模拟 功能性能 

分 类 号：TG139[一般工业技术—材料科学与工程]