| 摘要 |
PROBLEM TO BE SOLVED: To provide an anodic oxidation coating of an aluminum system material having higher adiabaticity, higher anticorrosion, higher durability, higher impact resistance, and higher water repellent and oil repellent functions, and to provide a method of processing the anodic oxidation coating, and a piston for an internal combustion engine.SOLUTION: A method includes the steps of applying AC/DC superposition electrolysis to an aluminum system material 1 to form a second anodic oxidation coating 2b, and then applying direct current electrolysis to the aluminum system material 1 to form a first anodic oxidation coating 2a. The second anodic oxidation coating 2b is thus formed on the first anodic oxidation coating 2a. |
