KMnO_4水溶液カソード処理によるアルミニウム陽極参加皮膜の硬質化 Hardening of anodized coating of aluminum by cathodic treatment in KMnO_4 electrolytic solution
Hard anodized coatings of aluminum have performed their parts most effectively in the fields for instance automobiles, precision machines, textile machines or sports, leisure industries. But in order to correspond to the propulsion of omission and available use of energy, hard anodized coatings will be demanded hardness and wear resistance further. On the background we have developed on aluminum anodized coating with excellent hardness and wear resistance. This coating is made by cathode electrolytic process in 0.1 N KMnO<sub>4</sub> aqueous solution before anodizing in sulfuric acid solution. The layer made by cathode electrolytic process is constituted of complex oxide with Mn, Al and O elements. We think that the chemical solution of porous anodic oxide film in sulfuric solution is controlled with existence of this complex oxide on porous layer of anodized coating. The results of this research will settle surely that it is very difficult to anodize for some aluminum alloy castings and aluminum alloys die castings with low coating ratio on anodized coating.
軽金属 49(5), 204-208, 1999-05-30
The Japan Institute of Light Metals