Passivation （Passivation（chemistry）） of stamping parts is the final process of chemical cleaning and a key step. It intends to avoid data corrosion. For example, in the case of pickling, washing water, rinsing, metal looks very clean, very lively, and very simple corrosion, passivation treatment must be carried out immediately, and metal appearance maintenance film must be made after cleaning to slow down corrosion.

　　Compared with other surface treatment processes, passivation treatment of stamping parts has the following advantages:

　　1) Compared with the traditional physical closing method, passivation treatment has the characteristics of never adding workpiece thickness, changing color, improving product precision and added value, making operation more convenient;

　　2) Because the passivation process of stamping parts does not respond, the passivation can be reused, thus the service life is longer and the cost is more economical.

　　3) The passivation promotes the formation of oxygen molecules in the passivated film structure of the outer surface of stamping parts, the film layer is precise and safe, and has a correction effect in the air at the same time. Compared with the traditional antitrust coating method, the composition of the passivated film is safer and more corrosion resistant.