SHIELDING GAS FOR MAG WELDING OF GALVANIZED SHEET STEEL, AND WELDING METHOD USING THE SHIELDING GAS

摘要

PROBLEM TO BE SOLVED: To provide shield gas for preventing generation of any blow holes or pits in a weld part when performing a lap fillet welding of a galvanized steel sheet by the MAG (metal active gas) welding method.;SOLUTION: A three component mixed gas composed of x vol.% of carbon dioxide, y vol.% of oxygen, and argon for the balance is used. The mixing ratio of carbon dioxide and oxygen simultaneously satisfies the following inequalities. y≤10 (1), y≥-x+45 (2), x≥40 (3), y≥-1/10x+5.5 (4), y≤1/20x-2 (5), y≥0 (6), y≥1/30x-5/3 (7), y≤-1/20x+5.5 (8), y≥3/40x-7/4 (9), and y≤-1/3x+35 (10).;COPYRIGHT: (C)2009,JPO&INPIT