Development of welding method for wide gap lap joint of steel sheet using laser welding with hot-wire

摘要

The hot-wire laser welding method was proposed for the lap joint of the high tensile / ultra-high tensile strength sheets with a wide gap, and its welding phenomenon was investigated precisely by using a high-speed camera, then the optimum welding conditions were obtained in this study. The obtained conclusions are as follows. l;The hot-wire laser system makes the penetrated hole and the molten pool by laser irradiation firstly, and then filler wire heated up by energization fills the penetrated hole in the proposed hot-wire laser lap welding method. The optimum conditions for the 1 mm gap are 1.5mm of the spot diameter, 3 mm of the wire feeding position, 70° of the wire feeding angle and 102 ~ 116 A of the wire current for 3kW of laser power, 1.5 m/min of the welding speed, 3.8 m/min of the wire feeding speed, 1 mm of the base sheet thickness and 1.2 mm of the filler wire diameter.