角接接头热源模型的应力场数值模拟

Numerical Simulation on Stressfield of Corner Joint Heat Source Model

根据角接接头焊接,分析了其焊缝的特性,在双椭球热源基础上改进其热源模型,以Q235为母材,依据试验及反演算法得出改进型双椭球热源参数并对其热源模型进行仿真,获得不同时刻的应力变化曲线规律及初始焊接与焊接末端应变角度的大小、应变位移变化及整个工件变形最大角度,验证了其上下焊缝应力及应变不对称原则,结果表明下侧板应变角度要大于上侧板但对应变形位移及扭曲程度要小于上侧板。该方法为合理选择焊接工艺参数、保证焊接质量及防止焊接变形提供依据参考。仿真结果表明,改进的热源模型正确。

According to comer joint welding, the weld features were analyzed and its heat source model was improved based on double ellipsoid heat source. The parameters of double ellipsoid heat source to simulation model with combining test results were obtained based on inversion algorithm taking Q235 as base material. The law of stress curves at different time, angle strain during the initial welding and welding end , maximum angle of strain and displacement transient stress at deformation of the entire workpiece were obtained, which proved the asymmetry principle of weld stress and strain. The results show that the angle of the lower plate is greater than that of the upper plate, but the corresponding displacement and deformation degree of distortion are less than those of the upper plate. The method can provide reference for the reasonable choice of welding parameters, welding quality assurance and preventing the welding deformation. The simulation results show that the improved heat source model is correct.