Method for Fusion Welding of One or More Steel Sheets of Press-Hardenable Steel

摘要

A method for fusion welding of one or more steel sheets (1, 2) made of press-hardened steel, preferably manganese-boron steel is disclosed. At least one of the steel sheets has a metallic coating (4) which contains aluminum, and the fusion welding is performed while filler material (11) is being fed into the molten bath (9). In order to improve the hardenability of the weld seam (14), irrespective of whether the steel sheets to be welded together are steel sheets of the same or different material grades and/or steel sheets of different sheet thicknesses, a single laser focal spot (16) with different energy distribution is generated on the molten bath by means of one or more optical elements such that the laser focal spot (16) has a smaller laser focal spot area (16.1) and a larger laser focal spot area (16.2).