THIN-SHEET ZINC-COATED AND CARBON-STEELS LASER-WELDING

This paper describes the results of a research on CO2 laser welding of thin-sheet carbon steels (zinc-coated and uncoated), at several thick nesses combinations. Laser welding has an high potential to be applied on sub-assemblies welding before forming to the automotive industry - tailored blanks. The welding process is studied through the analysis of parameters optimization, metallurgical quality and induced distorti ons by the welding process. The clamping system and the gas protection system developed are fully described. These systems allow the minimiz ation of common thin-sheet laser welding defects like misalignement, a nd zinc-coated laser welding defects like porous and zinc volatilizati on. The laser welding quality is acessed by DIN 8563 standart, and by tensile, microhardness and corrosion tests.