Because of the presence of lower-level automation and efficiency in the backing welding of medium–thick plates,pulse-metalactive-gas–metal-inert-gas(MAG–MIG)dual-arc welding was applied to backing welding of 24-mm-...Because of the presence of lower-level automation and efficiency in the backing welding of medium–thick plates,pulse-metalactive-gas–metal-inert-gas(MAG–MIG)dual-arc welding was applied to backing welding of 24-mm-thick Q235-B plate and the process and mechanism of root welding with back formation were investigated.The heating position of the MAG-arc at the front of the molten pool could be adjusted by using the electromagnetic force between the MAG-arc and the MIG-arc,and part of the arc energy could work on the root face directly.By combining the arc-discharge behaviour and analysis of flow in the molten pool,the shear stress of a tungsten inert gas(TIG)arc to the molten pool could make the liquid metal flow backwards.Thus,the quality of the front and bottom liquid metal were reduced,which favored the balance and stability.Continuous and stable back formation with uniform penetration could be achieved by using the pulse MAG–TIG dual-arc welding technology.展开更多
基金Innovation Research Group Project of National Natural Science Foundation of China(51621064)The National Natural Science Foundation General Projects(11375038).
文摘Because of the presence of lower-level automation and efficiency in the backing welding of medium–thick plates,pulse-metalactive-gas–metal-inert-gas(MAG–MIG)dual-arc welding was applied to backing welding of 24-mm-thick Q235-B plate and the process and mechanism of root welding with back formation were investigated.The heating position of the MAG-arc at the front of the molten pool could be adjusted by using the electromagnetic force between the MAG-arc and the MIG-arc,and part of the arc energy could work on the root face directly.By combining the arc-discharge behaviour and analysis of flow in the molten pool,the shear stress of a tungsten inert gas(TIG)arc to the molten pool could make the liquid metal flow backwards.Thus,the quality of the front and bottom liquid metal were reduced,which favored the balance and stability.Continuous and stable back formation with uniform penetration could be achieved by using the pulse MAG–TIG dual-arc welding technology.
