Effect of Current Parameters on Arc Striking and Spatter of Steel and Aluminum Wires during Percussive Welding

The percussive welding experiments of steel and aluminum wires were carried out by using high-frequency inverter power supply.Collecting the welding process current signal and using high-speed photography to study the arc striking process and the welding spatter, and the effects of welding current parameters on the morphology and tensile load of the welding spots were analyzed.The results show that with the increase of the coil current, the arc striking time is advanced, under the slow rising step current mode, the instant current of arc striking decreases, meanwhile the current rising rate is slow, and the failure of arc striking is easy to occur.But the three-stage current mode is not affected, because its arc striking current is large, the rising rate is fast, and the electric field is strong, it can strike the arc quickly.The insufficient arc spacing during welding is more likely to cause short-circuit, explosion and splash of molten droplets.Increasing the current of electromagnetic coil can inhibit amplitude of shrapnel to ensure the arc spacing and reduce the occurrence of splash.Under the three-stage step current mode, adjusting the coil current to 14.5 A can reduce arc failure and spatter in the welding process, and obtain welding spot with good morphology and stable tensile load.