摘要
通过TIG焊对TC4/TC18异种钛合金进行焊接,利用光学显微镜、显微维氏硬度计和拉伸试验机,研究了焊接电流对异种钛合金焊接接头显微组织和力学性能的影响。结果表明,在不同的焊接电流下,母材至焊缝中心的显微组织变化规律是一致的,随着电流的增大,TC4侧热影响区显微组织变化不大,TC18侧热影响区晶粒先长大后减小。焊后TC18母材一侧热影响区出现软化现象,而TC4母材一侧热影响区出现硬化现象。拉伸断口均靠近TC18热影响区一侧,焊接头的抗拉强度均高于母材的73%。基于SYSWELD焊接模拟软件,模拟得出TC4/TC18的焊接头残余应力集中在TC18侧热影响区,与拉伸试验断裂结果相吻合。
The TIG welding experiment of dissimilar titanium alloys （TC4/TC18） was carried out and the influence of welding current on microstrueture and mechanical properties of welded joint of dissimilar titanium alloys was studied, using optical microscopy, vickers hardness tester and tensile testing machine. The results show that under the condition of the different welding current, the changes of microstructure are consistent from the base metal to the welding center and the mierostrueture of the heat affected zone located on the TC4 side has little change with the increase of current, however, the grain size of the heat affected zone located on the TC18 side increases at first then decreases. The heat affected zone of the TC18 base metal was softened and the hardening phenomenon occurred in the heat affected zone of the TC4 base metal. The tensile strength of the welded joint is 73% higher than that of the base metal and the tensile fracture is near to one side of the TC18 heat affected zone. Based on the SYSWELD welding simulation results,the residual stress of the welded joint of TC4/TC18 is concentrated in the heat affected zone of the TC18 ,which is agreement with the result of the tensile test.
出处
《金属热处理》
CAS
CSCD
北大核心
2017年第1期166-170,共5页
Heat Treatment of Metals
基金
国家自然科学基金(51401175)
湖南省自然科学基金(2015JJ3123)
湖南省重点研发计划(2015WK3021)
湘潭大学大学生研究性学习和创新项目
关键词
异种钛合金
显微组织
显微硬度
力学性能
dissimilar titanium alloy
mierostrueture
microhardness
mechanical properties
作者简介
作者简介：许艳飞（1982-），女，博士，主要从事医用钛合金的成分设计、微观结构与力学性能以及钛合金异种金属焊接等方面的研究，E-mail：xuyanfei@xtu．edu．cn。
通讯作者：肖逸锋，副教授，E-mail：xiaoyifeng@xtu．edu．cn
