Method for butt laser welding two metal sheets with first and second front laser beams and rear laser beam

摘要

This method for laser welding butt two metal sheets (2, 4), -Providing a first metal sheet (2) and a second metal sheet (4); -Butt welding of the metal sheets (2, 4) along the welding direction, The butt welding step includes:-creating a first front spot 18 at the intersection with the first metal sheet 2 and a second front keyhole in the first metal sheet 2 at the first front spot 18 ( 19) a first front laser beam 12 which produces; -A second front laser beam generating a second front spot 20 at the intersection with the second metal sheet, and a second front keyhole in the second metal sheet 4 at the second front spot 20 ( 14); -Create a rear spot 22 in the first and second metal sheets 2, 4, and a rear keyhole 23A in the first and second metal sheets 2, 4 in the rear spot 22 Generating a rear laser beam 16; The first and second front laser beams 12, 14 and the rear laser beam 16 are, at every moment, the solid phase region 25 and/or the liquid phase region 13, 23B of the metal sheets 2, 4 ) Is configured in such a way that it is held between the first front keyhole 19 and the rear keyhole 23A and between the second front keyhole and the rear keyhole 23A.