| 摘要 |
PURPOSE:To prevent a crack at welding and to perform welding with high efficiency, by moving a welding position by a prescribed distance decided by chrome equivalent and nickel equivalent of each steel material, and irradiating a laser beam, when butting and welding the steel materials. CONSTITUTION:When butting and welding the first base metal 1 of chrome equivalent X1 decided by (%chrome + %molybdenum + %silicon X1.5+ %Nb X0.5), and nickel equivalent y1 decided by (%nickel + %carbon X30 + %manganese X0.5), containing low carbon steel, and the second base metal 2 of nickel equivalent y2 being different from this base metal 1 and chrome equivalent x2 being higher than the base metal 1, a beam 4 is irradiated by aiming at one line 6 at a position which has been moved to the base metal side whose chrome equivalent is high, by a distance (d) in parallel from an end part 5 both the base metals 1 and 2. This shifting dimension (d) is decided by chrome equivalent and nickel equivalent of each base metal 1 and 2. |
