| 摘要 |
PROBLEM TO BE SOLVED: To provide a two-phase stainless steel welded tube superior in corrosion resistance of a weld zone by welding with a laser beam under a preheating temperature and conditions satisfying some equations. SOLUTION: For the purpose of obtaining a two-phase stainless steel welded tube, preheating the abutted edges of a steel strip within a temperature range of the equation I is more effective than controlling the welding speed, thickness of the steel strip and laser output. In addition, for the purpose of performing complete through welding, it is necessary that a laser output PKw, preheating temperature T deg.C, welding speed Vm/min, thickness of a steel strip tmm and a constant (a) (=0.0006) are satisfied in the equation II. Thus, a two-phase stainless steel welded tube with a welded zone having the same corrosion resistance as the base stock can be manufactured by laser welding at a low cost. |
