基于平面变换的倾斜姿态双弧焊改进热源模型研究

Improved heat source model of tilted double arc welding based on planar transformation

用ANSYS软件模拟2 mm厚AZ31B镁合金薄板双弧焊接过程,对倾斜的TIG焊枪进行空间坐标转换,计算其焊接热输入,建立倾斜焊枪的热源模型,并与MIG电弧进行耦合,从而建立倾斜姿态下的双弧焊接热源模型。结合试验确定TIG电弧的焊接耦合率。模拟计算出焊接熔池并与试验进行对比,误差较小;在保持其他焊接参数不变的条件下,只改变旁路TIG电流,随着旁路电流的增加,熔宽略有减小,熔深显著减小。模拟与焊接理论及试验情况相符,验证双弧热源模型的正确性。

The numerical simulation of double-arc welding process of AZ31 B magnesium alloy sheet with 2 mm thickness was carried out by using ANSYS software. For the tilted TIG torch,the method of spatial coordinate transformation was used to calculate the welding heat input,and the heat source model of the tilted torch was established,and then coupled with the MIG arc. Thus a double-arc welding heat source model with tilted arc was established. The welding coupling rate of TIG arc was determined by simulation combined with experiment. The simulated weld pool was compared with the experiment,and the error was small. Under the condition of other welding parameters keeping constant and the bypass TIG current being changed only,with the increase of the bypass current,the weld width decreases slightly and the penetration depth decreases remarkably. The simulation is in good agreement with the welding theory and experiment,the correctness of the double arc heat source model is verified.