NiTi形状记忆合金和TC4的激光焊接裂纹产生机理分析(英文)  

Mechanism of Crack Formation in the Laser Welded Joint between NiTi Shape Memory Alloy and TC4

作　　者：宋鹏[1] 朱颖[1] 郭伟[1] 曲平[1] 康慧[1] 温凯[1] 

机构地区：[1]北京航空航天大学,北京100191

出　　处：《稀有金属材料与工程》2013年第S2期6-9,共4页Rare Metal Materials and Engineering

基　　金：The Fundamental Research Funds for the Central Universities

摘　　要：采用激光焊连接NiTi形状记忆合金与TC4钛合金,焊缝具有较大的裂纹倾向。采用扫描电子显微镜观察焊缝区域宏观形貌、微观组织和断口形貌;利用X射线衍射技术分析焊缝裂纹区域的相组成,从而研究焊缝产生冷裂纹的原因。结果表明:焊缝断口类型属于脆性断口,焊缝裂纹区域的相组成为NiTi2和NiTi金属间化合物,NiTi2金属间化合物所固有的特性导致焊缝变脆,在焊接应力的作用下焊缝产生裂纹。The laser welding experiment of NiTi shape memory alloy and Ti-6Al-4V(TC4) was performed,and the macro-morphology,phase constituents and microstructure of the joint were investigated using SEM equipped with energy dispersive spectroscopy(EDS) and XRD.The results show that the laser welded joint between NiTi shape memory alloy and Ti-6Al-4V(TC4) has a great tendency to crack.The joint is composed of NiTi2 and NiTi intermetallic compounds,and the intrinsic characteristics of NiTi2 phase lead the joint to be brittle.Cracks appear under the residual stress in the joint.

关 键 词：NITI形状记忆合金 TC4 激光焊 焊接裂纹 

分 类 号：TG456.7[金属学及工艺—焊接]