外拘束力对堆焊焊接残余应力的影响  

Effects of External Restraining Forces on Bead-on-plate Welding Residual Stress

作　　者：刘川[1] 张建勋[1] 

机构地区：[1]西安交通大学,西安710049

出　　处：《中国机械工程》2009年第10期1234-1239,共6页China Mechanical Engineering

基　　金：国家自然科学基金资助项目(50475093);中国机械工程学会焊接学会创新思路预研奖学金资助项目(07-12-003)

摘　　要：采用考虑压板、焊接件和工作台的有限元模型研究初始外拘束力对堆焊焊接残余应力的影响,分析拘束释放前后的残余应力分布,比较多体耦合模型和位移约束模型的计算结果,并与试验结果进行对比。结果表明:位移约束模型计算的残余应力比多体耦合模型计算的残余应力大,多体耦合模型能更好地反映实际试验条件;随外拘束力增大,焊缝中心上表面横向残余应力增大,下表面残余应力减小,当外拘束力增大到一定程度时,随拘束力增大,上表面横向残余应力减小,下表面残余应力增大;拘束位置距焊缝较远时,拘束释放使焊缝上表面的横向残余应力减小,而焊缝中心下表面的横向残余应力增大。A finite element model including clamp, clamping strip,worktable and welding plate was developed to simulate the welding residual stress with external restraining forces. The effect of restraining force release on welding residual stress was investigated, residual stress form multi--body coupling model were compared with those from displacement constraints model. Experiments were also carried out to measure the transient distortions and restraining forces during welding to validate the model. The analysis results show that the calculated transverse residual stress with displacement constraints model is larger than that with multi--body coupling model, the restraints in the multi-- body coupling model are more close to that in the experiments; the transverse welding residual stress at the welding center line on top surface increases with the restraining force increases, and decreases on bottom surface,when the restraining force come to a certain larger value, an inverse phenomena occurs; when restraining force is far from the welding center line, the transverse welding residual stress at the welding center line on top surface decreases and increases on bottom surface after the restraints are released.

关 键 词：残余应力 拘束力 多体耦合 有限元 

分 类 号：TG404[金属学及工艺—焊接]