旁路耦合电弧焊温度场模拟及验证

针对旁路耦合电弧焊的特点, 建立了一种适于用旁路耦合电弧焊的复合热源模型. 利用该热源模型对不同焊接参数下的旁路耦合电弧焊温度场进行了数值分析, 得到了总电流相同时不同旁路电流下的焊缝熔深、母材温度和特征点焊接热循环曲线的模拟结果, 分析了旁路耦合电弧焊焊接参数对母材热输入的影响, 并将特征点热循环曲线的模拟结果与相同条件下的试验结果进行了比较. 结果表明, 焊接总电流相同时母材热输入随着旁路电流的增加而降低, 且越靠近焊缝母材热输入的降幅越大, 特征点焊接热循环曲线的模拟结果与试验结果基本一致, 旁路耦合电弧焊温度场模型是合理的, 所建立的热源模型能够正确反映焊接参数与母材热输入之间的关系.

Numerical simulation of temperature field of DE-GMAW and its comparison with experimental measurements

Based on the features of DE-GMAW (double electrode gas metal arc welding), a new hybrid heat-source model that is suited for the DE-GMAW is established. Using this heat-source model, the temperature fields of DE-GMAW wtih different welding parameters are simulated. According to the simulation results with different welding parameters, in this article we analyze the influence of welding parameters on the heat input of base metal in DE-GMAW. To verify the rationality of the hybrid heat-source model of DE-GMAW, the simulation results of the temperature field are compared with the results obtained from the experiment that is carried out under the same condition. The research results indicate that under the same total current, the heat input of base metal decreases gradually with the increase of by-pass current. Moreover, the closer to the welding line the greater the decrease rate of the heat input of base metal is. The study and the comparison of the thermal cycle curve of measured points show that the simulation results are in good agreement with the experimental results. These results indicate that the temperature field model is accurate and the hybrid heat-source model is reasonable.