| 摘要 |
PURPOSE:To join an aluminum alloy without a weld defect such as a weld crack, etc., by irradiating with a pulse laser beam. CONSTITUTION:Four pulses LB (1) to LB (4) are repeated with an intermittent time (for instance, lmsec) in a laser output waveform per one time or one cycle. The peak values of these pulses LB (1) to LB (4) go down successively, that is, in order of LB (1), LB (2), LB (3), and LB (4). When the weld zone of a material to be welded, being made of an aluminum alloy, is irradiated with such a pulse laser beam LB, a crack does not occur except for only on the surface part of a molten metal part in a weld zone. The crack occurred on this surface part does not cross the joint surface of the material to be welded, and it is not a weld defect. |
