残余应力对焊接接头动态力学性能的影响  

Influence of residual stress on dynamic mechanical properties of welded joints

作　　者：罗家元[1] 谭超 李鑫 LUO Jiayuan;TAN Chao;LI Xin(College of Mechanotronics and Vehicle Engineering,Chongqing Jiaotong University,Chongqing 400074,China)

机构地区：[1]重庆交通大学机电与车辆工程学院,重庆400074

出　　处：《兵器材料科学与工程》2022年第6期31-36,共6页Ordnance Material Science and Engineering

基　　金：国家重点研发计划项目(2020YFF0404209);重庆市技术创新与应用发展专项重点项目(cstc2021jscx-dxwtBX0022);重庆市博士后特别资助项目(Xm2017034)。

摘　　要：为研究焊接残余应力对接头动态力学性能的影响,用Abaqus数值仿真,分析铝合金T型接头的温度场与残余应力场,通过Johnson-Cook本构与损伤模型建立T型接头动态拉伸有限元模型,分析残余应力对力学性能的影响,后通过3个断裂性能指标综合分析残余应力对断裂性能的影响。结果表明:动态拉伸下,残余应力降低力学性能,随应变速率增大,残余应力影响越大,静态拉伸下残余应力对接头的力学性能无影响。弹塑性阶段在焊接残余应力的影响下易发生脆性断裂,破坏阶段易断裂的位置与残余应力位置有关。In order to study the effect of welding residual stress on the dynamic mechanical properties of welded joints,Abaqus numerical simulation was used to analyze the temperature field and residual stress field of the aluminum alloy T-joint,and the dynamic tension of the T-joint was established by the Johnson-Cook constitutive and damage model.The finite element model was used to analyze the influence of residual stress on mechanical properties.Finally,the influence of residual stress on fracture properties was comprehensively analyzed through three fracture performance indicators.The results show that the residual stress will reduce the mechanical properties of the welded joints under dynamic stretching,and with the increase of the stretching rate,the residual stress has a greater influence,while the residual stress under static stretching has no effect on the mechanical properties of the welded joints.In the elastic-plastic stage,brittle fracture is likely to occur under the influence of welding residual stress,and in the failure stage,the fracture position is the same as the position where residual stress is not considered.

关 键 词：残余应力 动态拉伸 力学性能 断裂性能 

分 类 号：TG407[金属学及工艺—焊接]