| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for manufacturing a joined body by a welding method in which laser beam is branched into many laser beams by using diffractive optical elements so that many positions are simultaneously welded, which can reduce occurence (dispersion) of sputter caused by local excessive melting and occurrence of localized necking of welding sites caused by the sputter, and achieve high strength welding.SOLUTION: Strength is made different between branched laser beams L1 and L2 so that melted ranges by four laser beams L1 of laser beams, which is branched into multiple, for example, eight, and irradiated toward outer peripheral edges 17 of butting surfaces 13 and 23 of both members to be joined at equal angle intervals, overlap with each at center parts of the butting surfaces 13 and 23 and melted ranges by the other four laser beams L2 do not overlap with other at the center parts of the butting surfaces 13 and 23. This allows almost entire area of the butting surfaces to be efficiently welded without excessive melting at the centers of the butting surfaces 13 and 23, which can achieve high joining strength.SELECTED DRAWING: Figure 5 |
