基于复合热源模型的Al-Mg-Zn铝合金脉冲MIG焊接模拟

Simulation on pulsed-MIG welding process of Al-Mg-Zn aluminum alloy by FEA based on hybrid heat source model

针对脉冲MIG焊接试验过程建立了复合热源模型,并采用有限元软件ABAQUS对板厚15 mm的Al-Mg-Zn铝合金进行了多层多道脉冲MIG焊接的传热过程数值模拟.根据复合热源和单一双椭球热源进行计算对比.结果表明,该组合热源可以较好的模拟脉冲MIG焊接不同道次的熔池形貌,并且降低热源校准难度.同时,基于建立的复合热源模型,文中引入非线性弹性边界条件表征实际夹具工装,对脉冲MIG焊接过程的应力和变形分布进行仿真模拟,其中焊后变形分布规律和试验测量具有较好的一致性.

In this work,based on ABAQUS software,a hybrid heat source model was developed to simulate the multipass pulse MIG welding process of a 15 mm-thick Al-Mg-Zn alloy. Compared with double ellipsoid heat source,the coupled heat source could finely realize the weld pool fitting according to morphology of each pass,and apparently reduced the complexity of parameters calibration for heat source. By applying the heat source model and nonlinearly elastic boundary conditions,the calculated weldment morphology and residual distortion had a well agreement with welding experiments.