Influence of Additives on Room Temperature Hard Anodizing of Aluminum Alloy

The traditional process of hard anodic oxidation of aluminum has some shortcomings such as high energy consumption, easy burn, needs of low-temperature and high voltage. Oxalic acid, glycerol and NiSO4 were added into the electrolyte of anodic oxidation to raise the temperature limit of anodic oxidation, which made the hard anodizing can be carried out at room temperature. And by using orthogonal experiment method, the content of electrolyte additives was optimized and the best hard anodizing process at room temperature was obtained.