CMT Mix在铝合金电池托盘焊接中的工艺研究

Study on CMT Mix Welding Technology for Aluminum Alloy Battery Tray

针对铝合金电池托盘焊接中经常出现的过热变形、焊缝熔深不足、气孔倾向大等缺陷问题,以2.5 mm厚6061铝合金为研究对象,采用CMT Mix焊接工艺研究保护气种类、弧长修正以及电感修正对焊缝内部气孔、熔深及焊缝宽度的影响规律。结果表明:CMT Mix工艺结合了CMT短路过渡和脉冲过渡的双重特征,搭接焊缝表面成形良好,熔深满足要求,焊接过程飞溅少,焊缝内部的气孔得到有效控制,焊接接头符合T/CWAN 0027—2022电池托盘焊接制造规范。采用φ(Ar)70%+φ(He)30%混合气比纯Ar更有利于焊缝内部气孔的溢出,气孔数量和尺寸显著减小,保护效果更佳。弧长修正负向调节时,焊缝熔深增加,同时焊缝内部气孔数量及尺寸显著减小;电感修正负向调节时,焊缝熔深显著增加,但焊缝内部气孔尺寸明显增大;相较于弧长修正,电感修正对熔深的影响更为明显。

On account of the defects such as welding deformation, unqualified penetration and large porosity tendency in aluminum alloy battery trays welding, the 2.5 mm thickness 6061 aluminum alloy plate is taken as the research object. Based on the CMT Mix process from Fronius, the effects of shielding gas, Arclength correction and dynamic correction on the inner pore, penetration and weld width were studied. The results showe that the CMT Mix combines the characteristics of CMT short-circuit transfer and pulse transfer, the weld surface is well formed, the penetration is qualified, and the welding process has less spatter, the inner pores are well controlled, the welded joint is corresponding to the criterion of T/CWAN0027—2022 battery tray weld manufacturing. Compared with pure Ar shielding gas, the protection effect of Ar+30%He is better, the pore number and size are more significantly reduced. When the Arclength correction is negative, the penetration of the weld increases, while the number and size of the pores inside the weld significantly reduce;when the dynamic correction is negative, the penetration and the size of the pores inside the weld obviously increase. Compared to the Arclength correction,the dynamic correction has a more obvious effect on the penetration than that of Arclength correction.