摘要
The morphology of Ni_(4)Ti_(3) precipitates is important in tuning the martensitic transformation(MT)behavior and mechanical properties of nitinol.Constrained ageing is effective in engineering the morphology of Ni_(4)Ti_(3) precipitates due to the variant selection effect of external load which is still lacking.In this work,maps of variant selection effect of external load applied along all crystallographic directions are obtained by using a combination of theoretical analyses and phase field simulations.It is found that maps produced by uniaxial tension and uniaxial compression are quite different.The number and types of Ni_(4)Ti_(3) variants preferred by external load vary as the loading direction changes.Moreover,factors influencing the strength of variant selection effect are discovered.This work provides insights on understanding the Ni_(4)Ti_(3) precipitation process and sheds light on the engineering of morphology of Ni_(4)Ti_(3) precipitates for desired mechanical and functional properties.
Ni_(4)Ti_(3)沉淀物的形态对于调节镍钛诺的马氏体转变行为和力学性能非常重要.由于缺乏外部载荷的变体选择效应,限制时效在工程化Ni_(4)Ti_(3)沉淀物的形态方面非常有效.在本研究中,通过结合理论分析和相场模拟,获得了沿所有晶体学方向施加外部载荷的变体选择效应图.发现单向拉伸和单向压缩产生的图谱存在很大差异.外部载荷优选的Ni_(4)Ti_(3)变体的数量和类型随着加载方向的变化而变化.此外,还发现了影响变体选择效应强度的因素.这项工作为理解Ni_(4)Ti_(3)沉淀过程提供了见解,并为获得所需的机械和功能特性的Ni_(4)Ti_(3)沉淀物形态工程提供了启示.
作者
Xuewei Zhou
Tianlong Zhang
Li Cheng
Xusheng Yang
Jiaming Zhu
周学伟;张天隆;程利;杨许生;朱家明(School of Civil Engineering,Shandong University,Jinan 250061,China;Department of Mechanical Engineering,Hong Kong University of Science and Technology,Hong Kong,China;State Key Laboratory of Ultra-precision Machining Technology,Department of Industrial and Systems Engineering,The Hong Kong Polytechnic University,Hong Kong,China;Shenzhen Research Institute of Shandong University,Shenzhen 518057,China;Institute of Materials Intelligent Technology,Shenyang 110004,China)
基金
supported by the National Natural Science Foundation of China(Grant No.12372152)
the Qilu Young Talent Program of Shandong University,Zhejiang Lab Open Research Project(Grant No.K2022PE0AB05)
Shandong Provincial Natural Science Foundation(Grant No.ZR2023MA058)
Guangdong Basic and Applied Basic Research Foundation(Grant No.2023A1515011819).
