Method for Laser Beam Welding of One or More Steel Sheets Made of Press-Hardenable Manganese-Boron Steel

摘要

A method for laser beam welding of one or more steel sheets made of press-hardenable manganese-boron steel is disclosed. At least one of the steel sheets has a coating of aluminium. The laser beam welding takes place by feeding an additional wire into a melt bath generated by of a laser beam. The additional wire contains at least one austenite-stabilising alloy element. The weld seam after hot forming (press hardening) has a strength that is comparable to the base material. The laser beam is put into oscillation such that it oscillates transverse to the welding direction, wherein the oscillation frequency of the laser beam is at least 200 Hz, preferably at least 500 Hz. The method dispenses with removing the aluminum coating at the edge of the sheet-metal edges to be welded.