| 摘要 |
PROBLEM TO BE SOLVED: To provide an aluminum anodic oxide coating capable of achieving high withstand voltage performance by suppressing occurence of cracks in a bent part, and as a result, suppressing corrosion of a base material under a corrosion gas atmosphere and deterioration of withstand voltage performance due to cracks of the coating.SOLUTION: The anodic oxide coating formed on a surface of a base material consisting of aluminum or aluminum alloy has a coating structure which is a single-layer anodic oxide coating or is laminated by two or more kinds of anodic oxide coatings. The anodic oxide coating on the outermost surface side has 1.3 or more of a coating formation rate defined by the following formula (1), and the thickness of the anodic oxide coating is 3% or more by a ratio to the thickness of the whole coating, where the formula (1) is a coating formation rate=an anodic oxide coating thickness/a base material reduction thickness during anodization. |
