| 摘要 |
PURPOSE:To weld both matierials excellently even at low level of laser output at the lap welding with using laser, by forming an exposed part, at the front of the laser beam, stepwise with sharp edges. CONSTITUTION:A spring material 12 to be welded is lapped on an other point- contact material 11 having high heat conductivity. In the material 12, holes 13 decreasing their diameters in series toward the point-contact part 11 are drilled, the holes are formed e.g. a large dia. part 14a, a middle part 14b, a small dia. part 14c are formed concentrically in 3 steps. Accordingly, 2 horizontal stepped parts 15a, 15b are formed. When the laser beam is irradiated toward the holes 13, the edge parts 19a, b of respective parts 15a, b are molten, and flows to the hole 14c to be well fused with a molten part of the material 10 thereby forming a welded part 20 free from space. Thus the materials 11 and 12 are welded highly strongly. |
