随焊氩气激冷控制铝/钢薄板焊接应力与变形数值模拟

采用有限元分析软件ANSYS,对不同焊接工艺条件下铝/钢异种金属薄板对接熔钎焊接过程进行数值模拟,建立了TIG电弧热源与氩气冷源模型,将常规焊接和随焊氩气激冷焊接的残余应力与变形进行对比分析,研究发现:随焊氩气激冷技术可使焊接纵向残余应力和变形分别降低32.8%和48.1%。为了验证数值模拟结果的准确性,进行了铝/钢异种金属薄板熔钎焊试验,将温度场与应力场的模拟值与试验值进行对比,结果显示两者吻合较好,表明随焊氩气激冷技术可有效控制铝/钢薄板焊接残余应力与变形。

Numerical simulation of stress and deformation for Al/steel sheet welding by trailing cooling of argon gas

The numerical simulation of butt brazing process of Al/steel dissimilar metal sheet under different welding conditions was carried out by using finite element analysis software ANSYS. Two models are established for TIG arc heat source and cold source respectively. Comparative analyses of residual stress and deformation reveal that the argon quenching at low temperature in the process of welding can effectively reduce longitudinal residual stress and deformation in the weld, resulting in apparent reduction by 32.8% and 48.1%, respectively. In order to verify the validity and prove the accuracy of our finite element simulation results, a welding test of Al/steel dissimilar metal sheet was carried out. Through analytical comparisons of the predicted results of temperature field and stress field and with tested ones, it is verified the effectiveness of the numerical model. It has been shown that the residual stress and deformation in Al/steel sheet welds can be effectively controlled by argon quenching technology.