Metal surface passivation is a common method for metal corrosion protection. It improves the corrosion resistance of metals by forming a passivation film on the metal surface.

The principle is based on the chemical reaction between the metal and substances in the environment such as oxygen, water, and acids to form a stable oxide film or compound film that protects the metal surface.

This film possesses strong adhesion and corrosion resistance, preventing further reactions between the metal surface and the external environment, thus extending the metal's service life. Passivation treatment can be applied to various metals, such as steel, aluminum alloys, and copper alloys. It is used in industrial manufacturing, construction, transportation, aerospace, and other fields to prevent metals from rusting and corroding.

Advantages of passivation

1. Compared to traditional physical sealing methods, passivation treatment does not increase workpiece thickness or change color, and improves product precision and added value, while being more convenient to operate.
2. Because the passivation process is carried out in a non-reactive state, the passivating agent can be repeatedly added and reused, resulting in a longer lifespan and lower cost.
3. Passivation promotes the formation of an oxygen molecular structure passivation film on the metal surface. This film is dense, stable, and has a self-healing effect in air. Therefore, compared to traditional methods of applying rust-preventive oil, the passivation film formed by passivation is more stable and has better corrosion resistance.