| 摘要 |
PURPOSE:To enable a laser welding with a lower power density in the laser welding of Al alloys with different materials by irradiating it with a laser beam from the side of the Al alloy whose mol fractions in elements having a boiling point lower than that of Al contained in the Al alloys are higher. CONSTITUTION:In the case of performing a laser welding by superposing the shapes of welding joints for the Al alloys with different materials, the Al alloy 1 in the 5000 system is placed at an upper side, which is the Al alloy having higher mol fractions in the elements with a boiling point lower than Al such as Mg and Zn contained in the Al alloys. By placing the Al alloy 2 in the 6000 system at a down side which is the Al alloy having lower mol fractions, the alloys are irradiated with a laser beam 3 from the side of the Al alloy 1 in the 5000 system. Consequently, a molten solidified metal is formed more deeply and the depth of penetration is larger by being irradiated with the laser beam 3 from the side of the Al alloy 1 in the 5000 system than by being irradiated from the side of the Al alloy 2 in the 6000 system. Thus, the laser beam 3 with a low power density is sufficient. |
