Laser welding method for a hard aluminum alloy sheet

The invention discloses a laser welding method for a hard aluminum alloy sheet. The method comprises the following steps that (1) a to-be-welded workpiece A and a to-be-welded workpiece B are taken, and a sunken vertical surface with the depth being equal to the thickness of the workpiece B is machined on the workpiece A; (2) the workpiece B is arranged on the sunken vertical surface, and the sunken vertical surface and the workpiece B are in butt joint and are positioned; (3) a V-shaped groove is machined in the surface of a weld through a planer tool mechanism; (4) the upper surface of the workpiece A and the upper surface of the workpiece B are ground through a wire brush; (5) the workpiece A and the workpiece B are welded through a laser wire feeding device, wherein the laser power is2-6 kw, the wire feeding diameter is 0.8-1.2 mm, the wire feeding speed is controlled to be 2-10 m/min, the surface of the welded weld is 0.1-0.2 mm higher than the surface of the workpiece A and thesurface of the workpiece B