PROCÉDÉ POUR LE SOUDAGE LASER D'UNE OU DE PLUSIEURS TÔLES D'ACIER CONSTITUÉES D'ACIER AU BORE ET AU MANGANÈSE POUVANT ÊTRE EMBOUTI À CHAUD

摘要

The invention relates to a method for laser beam welding of one or more steel sheets made of press-hardenable manganese-boron steel, wherein at least one of the steel sheets (1, 2, 2') has a coating (4) of aluminum. The laser beam welding is done by feeding additional wire (11) into the melt bath (9) generated exclusively by means of a laser beam (6), wherein the additional wire (11) contains at least one austenite-stabilizing alloy element. The aim of the invention is to achieve, at relatively low energy consumption and high productivity, that the weld seam after hot forming (press hardening) has a strength that is comparable to the base material. This aim is achieved, according to the invention, in that the laser beam (6) is put in oscillation in such a way that the laser beam oscillates transversely to the welding direction, wherein the oscillation frequency of the laser beam (6) is at least 200 Hz, preferably at least 500 Hz. The method according to the invention offers, in particular, cost advantages, since the method allows to dispense with removing the aluminum coating at the edge of the sheet-metal edges to be welded.