What is passivation?
Passivation treatment: The process of forming a trivalent or hexavalent chromated layer on the surface with a chromate solution and metal, known as passivation, also known as chromizing.
The chemical activity of different metals varies greatly. Active metals are highly susceptible to corrosion in environmental media, while non-reactive metals exhibit good corrosion resistance. However, some of the more active metals are supposed to be corrosive in some environments, but they are unusually corrosion-resistant. If the electrode potential of aluminum is much higher than that of hydrogen, it should be rapidly corroded in aqueous solution. However, aluminum is resistant to corrosion by water and humid atmosphere. Because aluminum is easily passivated by oxygen in the air, it is widely used as cutlery and building decoration materials.
The passivation mechanism can be mainly explained by thin film theory. It is considered that the passivation is due to the interaction of the metal with the oxidizing medium, and a very thin, dense, well-covering, and strong covering metal can be formed on the metal surface. Passivation film on the surface. This layer of film exists as a separate phase, usually oxygen and metal compounds. It plays a role in completely separating the metal from the corrosive medium, preventing the metal from directly contacting the corrosive medium, so that the metal basically stops dissolving to form a passivation state to prevent corrosion.
The Main Purpose
Fully pickling and passivation of metal parts, remove all kinds of oil, rust, oxide scale, welding spot and other dirt. After treatment, the surface becomes uniform silver white, greatly improve the corrosion resistance of metal, applicable to various types of metal parts, plates and Its equipment.
The operation is simple, easy to use, economical and practical. At the same time, high-efficiency corrosion inhibitors and fog inhibitors are added to prevent over-corrosion and hydrogen embrittlement of metals and to suppress the generation of acid mist. Particularly suitable for small and complex parts, not suitable for the case of paste, better than similar products in the market.
The advantages of passivation are:
1. The liquid is stable and non-volatile, and can be reused. Compared with anti-rust oil, it can save more than 40% of cost. Compared with the traditional physical enclosure method, the passivation process has the feature of absolutely not increasing the thickness and color of the workpiece.
2. The surface of the treated workpiece is non-greasy, clean and fresh. Since the passivation process is carried out in an unreacted state, the passivating agent can be repeatedly added and used, so that the lifespan is longer and the cost is more economical.
3. The passivation film formed is more robust, less likely to be destroyed and removed, and the performance is more stable and the corrosion resistance is improved 8-50 times. Passivation promotes the formation of oxygen molecular structure passivation film on the metal surface, dense film layer, stable performance, and self-repair in the air at the same time, so compared with the traditional anti-rust oil, more stable and more corrosion-resistant.