Method of Laser Welding Coated Steel Sheets with Addition of Alloying Elements

摘要

A process is described for laser welding a sheet metal workpiece having an aluminum-silicon containing pre-coat layer disposed on at least one major surface thereof, and having first and second opposite side edges. The sheet metal workpiece is arranged such that the first and second side edges are in contact with one another and such that the at least one major surface faces outwardly. A closed tube-shaped product is obtained by forming a laser-weld joint between the first and second side edges. In particular the laser-weld joint is formed absent removing the aluminum-silicon containing layer from along the adjacent edges, such that aluminum from the aluminum-silicon containing layer enters into the melt pool that is formed. An alloying material is introduced into the melt pool during laser welding and forms a compound with at least some of the aluminum in the melt pool.

主权项

1. A process for laser welding a sheet metal workpiece, at least one major surface of the sheet metal workpiece being pre-coated with an aluminum-silicon containing layer, and the sheet metal workpiece having a first side edge and a second side edge that is opposite the first side edge, the process comprising:
arranging the pre-coated sheet metal workpiece such that the first side edge is adjacent to and in contact with the second side edge, and such that the at least one major surface faces outwardly; forming a laser weld joint along the adjacent edges of the pre-coated sheet metal workpiece, absent removing the aluminum-silicon containing layer from along said adjacent edges, such that aluminum from the aluminum-silicon containing layer enters a melt pool that is formed during forming the laser weld joint; and introducing an alloying material into the melt pool during forming the laser weld joint, wherein the alloying material and at least some of the aluminum that enters the melt pool from the aluminum-silicon layer forms a compound in the melt pool.