CO₂ laser-weldability of zinc coated steel sheets (Ⅱ)

CO₂ laser butt welding of zinc coated steel sheets cut by CO₂ laser was investigated regarding with automotive manufacture. It was found that the yield stresses of the laser welding seams were larger than that of the matrix steels. The microstracture in the seems were characterized by needle-like ferrite with lower hardness. The sheets containing the laser welded seams maintained excellent deep dawning potential, and the destroyed zinc layer near the seams is less than 0.5 mm in width. The zinc layer protected the welded seams from corrosion through zinc self-sacrifice. The results indicated that the CO₂ laser butt welding is a robust technology for tailored welded blank manufacture, and laser cutting may be a promising tool in tailored welded blank manufacture.