| 摘要 |
<P>PROBLEM TO BE SOLVED: To eliminate color tone differences occurring between a portion corresponding to the opposite surface of a joining portion and the rest of the portion, in a coating formed by an anodic oxidation treatment of an aluminum alloy joining member. <P>SOLUTION: An aluminum alloy material used for forming the aluminum alloy joining member which is formed by joining the joining portion by friction stir welding includes, in mass%, more than 4.0% but 6.0% or less Mg, 0.2% or less Cu, 0.1% or less Si, 0.1% or less Fe, and the balance being Al and unavoidable impurities. By controlling the particle diameter of secondary phase particles distributed in the aluminum alloy to 5 μm or less, the secondary phase particles are more uniformly distributed in the portion corresponding to the joining portion of the aluminum alloy joining member, compared with the rest of the portion, so that the color tone differences on the anodic oxidation coating can be eliminated. <P>COPYRIGHT: (C)2012,JPO&INPIT |
