| 摘要 |
PROBLEM TO BE SOLVED: To simplify welding of a vehicle fuel tank and the like made of an aluminum plated sheet and to improve welding strength. SOLUTION: In manufacturing a fuel tank 1 through laser welding of peripheral flange parts 2a, 3a of a pair of halved shell bodies 2, 3 made of an aluminum plated sheet with an aluminum plated surface, the flange part 2a, 3a are put together one above the other in close contact, then the superposed part is irradiated with a laser beam and at the same time is subjected to blowing of a gaseous mixture composed of gaseous argon, helium and nitrogen or a gaseous mixture of 38-90% oxygen (vol.%) to gaseous carbon dioxide and thus welded. |
