| 摘要 |
PURPOSE:To prevent evaporation of zinc contained in a copper alloy by a simple method and to weld surely the copper alloy and other metal by coating preliminarily a light absorbent in a liquid state to the surface of a member consisting of the copper alloy an making incident the laser beam of relatively low energy density focusing in the space outside of said member and the surface coated with the light absorbent to said member. CONSTITUTION:A light absorbent 2 in a liquid state is coated on the surface of a brass member 1 placed on iron 3 and a laser beam 4 past a condenser lens 5 is made incident on the surface coated with the absorbent 2. The focus 6 of the highest energy density of the beam 4 is formed in the space excluding the object 1 to be welded and the absorbent 2, i.e., the space apart by 5mm. from the surface of the member 1. The diameter (d) of the laser beam is therefore expanded on the surface of the member 1 and about 1mm. beam diameter is formed, by which the member 1 can be welded to the iron 3. More specifically the energy is efficiently absorbed by the absorbent 2 even if the energy desity of the beam 4 is small and the scattering of zinc is prevented without breaking the film of the absorbent 2. |
