METHOD FOR IMPROVING FORMABILITY OF JOINT STOCK IN LASER BEAM WELDING

摘要

PURPOSE:To improve the ductility of a welded bead being a joint stock and to elevate the press formability of the joint stock by pressurizing the welded bead with a pressure roller immediately after laser beam welding is carried out. CONSTITUTION:Immediately after laser beam welding is carried out by laser beam 3, a welded bead 6 is pressurized by a pressure roller 2 rolling on the welded bead 6 in the direction of the welding line to improve the ductility of the laser beam welded part in the direction of the welding line. Since the welded bead 6 is pressurized immediately after the laser beam welding is carried out, the welded bead 6 is not solidified yet and pressurized and forged by the pressure roller 2. Structure is made dense by forging to improve the ductility of the welded part in the direction of the welded line. The welded bead is flattened nearly to the same level as the surface of the base material is, local concentration of stress due to the irregularity of the surface is reduced, ductility resistance is improved and the press formability of the joint stock 5 is elevated.