焊接残余形变在工件精密装配中的仿真应用研究

Application of welding residual deformation to simulation of precision assembly parts

基于非线性软件ABAQUS建立了某成分马氏体耐热不锈钢合金材料的喷嘴零件装配结构的焊接有限元模型，采用双椭球热源模型模拟了3种不同焊接工艺参数下其环缝处的焊接过程并进行了比较分析，得到了焊接温度场和接触应力、焊接残余应力、残余形变及焊接应变能分布规律。研究表明不同脉冲和电流的工艺参数下所产生的拉伸残余应力最大达285 MPa，最小达225 MPa，相差60 MPa；压缩残余应力最大达95 MPa，最小达75 MPa，相差20 MPa；最大压缩形变相差0．012 mm，最小稳定压缩残余形变相差0．004 mm。焊接残余应变能均匀变化在0．013～0．016之间，同时获得焊接残余形变量与配合公差之间的量化关系，为工件修复和循环使用提供焊接装配工艺理论和参数数据支撑。

A finite element model of welding structure of martensitic heat- resistance stainless steel jet assemble part was established based on ABAQUS software,and the temperature field and surface contact stress,residual stress,residual deformation and welding strain energy were calculated for circumferential seam by double ellipsoid model of heat source,which simulated the welding process.The research showed that the maximum tensile residual stress is 285 MPa,and the minimum value is 225 MPa,the discrepancy between them is 60 MPa at the different pulse and current.The maximum compression residual stress reaches 95 MPa,the minimum is 75 MPa,and the difference between them was20 MPa.The maximum compression deformation is 0.012 mm,the minimum stability is 0.004 mm,while the welding residual strain energy can change uniformly in the range of 0.013~0.016.At the same time,the quantitative relationship between fit tolerance and welding residual deformation was obtained,which can provide the support of the process theory and parameter of repairing and recycling.