电弧预熔丝激光焊焊接特性研究

Laser welding with pre-melted liquid filler by arc was developed to solve the problems, such as the reflection of incident laser energy by filler wire in the process of laser welding with filler wire for aluminum alloy. The liquid filler was pre-melted by energy of arc and then flowed into the molten pool. The effects of the welding current on melting of the filler wire and the weld appearances were studied. And the influence of wire filling on the stability of keyhole and the quality of welded joint were analyzed. The results indicated that with the increase of welding current, the melting length of the front end of the filling wire increased. When the welding current was larger, it was unfavorable to the melting and filling of the filling wire. Compared with laser welding with filler wire, the end of the melted filler wire flowed along edge of the molten pool, the distance between the end of the filler and the keyhole edge was far in laser welding with pre-melted liquid filler by arc. The laser welding with pre-melted liquid filler by arc process had better stability of the keyhole, had less the number of weld pores, and got high the tensile strength for weld joints. When the welding speed was 4 m•min^-1, the surface and back weld seams of laser welding with filler wire and laser welding with pre-melted liquid filler by arc were well. When the welding speed was 8 m•min^-1, the weld seams were well formed without welding defects. This showed that the filling wire was melted mainly dependent on the energy melting of the arc in laser welding with pre-melted liquid filler by arc. So the stability of the laser welding process would not be affected by the slight fluctuation of the wire.