焊接工艺对铝合金脉冲MIG横焊气孔敏感性的影响

在铝合金大型结构件焊接中横焊的难度最大,如何减少焊缝气孔缺陷是当前的研究热点之一。以1561铝合金板脉冲MIG横焊为研究对象,通过X射线探伤和显微组织观察系统分析了不同焊接工艺参数对气孔敏感性的影响,结果显示:氦气与氩气混合气在一定比例范围内,焊前高温预热、电弧上倾,均有利于熔池气体逸出;电弧电压和焊接速度的增加有利于减少焊缝大气孔,而随着焊接电流增加,焊缝大气孔数量增加。该研究可为铝合金横焊工艺的优化提供试验依据。

Effect of welding process on the porosity sensitivity of aluminum alloy pulse MIG horizontal welding

In the welding of aluminum alloy large-scale structural parts,horizontal welding is the most difficult technique. How to reduce weld porosity defects is one of the current research hotspots. The pulsed MIG horizontal welding of 1561 aluminum alloy plates was studied in this paper. The effect of different welding process parameters on the porosity sensitivity was analyzed by X-ray detection and microstructure observation. The results show that the mixture ratio of helium and argon gas in a certain range,the high temperature preheating,the arc tilted upwards,are conducive to gas escaping from molten pool. With the increase of arc voltage and welding speed,it is beneficial to reduce the number of large pores in the weld,and with the increase of welding current,the number of large pores increases. This study can provide a solid experimental basis for the optimization of the welding process for horizontal welding of aluminum alloy.