SHIELD GAS FOR HYBRID WELDING, AND HYBRID WELDING METHOD USING THE SHIELD GAS

摘要

PPROBLEM TO BE SOLVED: To obtain a shield gas for hybrid welding, which causes no generation of pits in a weld part, and is capable of preventing any burn-through or hole in a weld metal, as a shield gas which is used when performing the lap welding of a galvanized steel sheet by using the laser welding and the arc welding in combination. PSOLUTION: A mixture gas consisting of an argon gas, a carbon dioxide gas, and an oxygen gas is used for a shield gas. When a gap between steel sheets is zero, the mixing ratio of the carbon dioxide gas and the oxygen gas is regulated to be in ranges to satisfy inequalities of 15A50, 5B9, and B21-0.8A, wherein A denotes the volume percentage of the carbon dioxide gas in the shield gas and B denotes the volume percentage of the oxygen gas, and the balance consists of the argon gas. PCOPYRIGHT: (C)2007,JPO&INPIT