| 摘要 |
PROBLEM TO BE SOLVED: To provide a multi-layer coated aluminum substrate that can be preferably used as a member such as an engine member where heat insulation property is required, is excellent in adhesion to a substrate formed of aluminum or an aluminum alloy, and has sufficient heat insulation property.SOLUTION: In a multi-layer coated aluminum substrate where an alumite layer and a ceramic layer are sequentially formed on a substrate formed of aluminum or an aluminum alloy, the alumite layer has a plurality of cracks reaching a substrate surface, a distance between internal walls facing each other inside a crack is 0.2 to 5 μm, and the ceramic layer enters inside the cracks. |
