Abstract: Laser welding process and apparatus wherein a plurality of laser beams are focussed by a focussing device on surfaces of workpieces such that spots of the laser beams are located in the vicinity of an interface as viewed in a direction perpendicular to a direction of extension of an interface of the workpiece, and the beam spots and the workpieces are fed relative to each other by a feeding device in the direction of extension of the interface, while at the same time the beam spots are oscillated by an oscillating device at a predetermined frequency relative to the workpieces in a direction intersecting the direction of extension of the interface such that the beam spots are moved across the interface.

Abstract: Sheared steel sheet materials are abutted against each other with burrs of the steel sheet materials directed in the same direction. A laser beam is irradiated onto the abutment portion of the assembly of the steel sheets from the sagging side of the assembly. At the same time, a filler wire is supplied to the abutment portion from the same side as the laser beam irradiation. The steel sheet materials are joined together to form a press material. Then, the press material is set in a press machine in a direction that a surface of the press material opposite to the laser beam irradiated surface, faces the exterior when stamped and mounted to a vehicle. Then, the press material is stamped and is formed into a vehicle panel.

Abstract: Metal sheets having different thicknesses are abutted to define an abutment line and then are laser-welded. During laser welding, the laser beam is directed to a line (a weld line) which is apart from the abutment line on a thicker sheet side. The distance between the abutment line and the weld line is preferably in the range of 0.1 mm to 0.4 mm. Preferably, the laser beam weaves from side to side with respect to the weld line. As a result, a sharp edge is removed from the thicker sheet and a smooth transient surface is formed on the weld bead. The resulting one-piece sheet can be used as a press material without any pre-pressing processing, such as grinding.