基于CMT的车用镁铝薄板件点焊变形研究

Research on Spot Welding Deformation of Vehicle Magnesium Aluminum Sheet Based on CMT

为研究镁铝薄板件CMT点焊变形问题,进行了镁铝薄板件CMT点焊试验和仿真分析。首先在铝板上搭接开孔直径为8mm的镁板进行点焊试验,并建立同等条件的有限元仿真模型,将试验所得和仿真所得的焊接变形量进行对比,验证仿真模型的准确性。然后分别选取小孔直径为6,8,10mm和板厚为1,2,3mm的镁板进行仿真分析,最后得出不同孔径和板厚下的焊接变形量。结果表明,镁铝焊接变形主要发生在镁板侧,且在夹持点处存在残余应力。在变量范围内,通过单因素实验,焊接试样的变形量随孔径和板厚的增大而减小。

In order to study the deformation of Mg-Al thin plate by CMT,spot welding test and simulation analysis are carried out.At first,spot welding test was carried out on a magnesium plate with a hole diameter of 8 mm overlapped on the aluminum plate,and a finite element simulation model with the same conditions was established to compare the welding deformation obtained from the test and the simulation to verify the accuracy of the simulation model.Then,magnesium plates with hole diameters of 6,8 and 10 mm and plate thickness of 1,2 and 3 mm were selected for simulation analysis,and the welding deformation under different pore diameters and plate thickness was finally obtained.The results show that the deformation of magnesium aluminum welding occurs mainly on the side of magnesium plate and there is residual stress at the clamping point.In the variable range,the deformation of the welded specimen decreases with the increase of aperture and plate thickness through single factor experiment.