Passivation technology enhances metal corrosion resistance and drives industrial progress

In modern industry, passivation technology is becoming an increasingly important means of enhancing the corrosion resistance of metallic materials. Passivation is used to protect materials from the external environment by forming a protective film on the metal surface. Especially in aluminium and stainless steel applications, passivation significantly extends product life and reduces maintenance costs.

Definition

Passivation is the formation of a thin film on the surface of a metal, either chemically or electrochemically, to reduce its reaction with the environment and thus increase its corrosion resistance. The process usually involves immersing the metal in a solution containing a passivating agent to form a protective oxide film.

Role

1、Improve corrosion resistance: passivation can form a thin film on the metal surface, preventing oxygen and moisture from coming into contact, thus reducing the occurrence of corrosion.

2、Enhance oxidation resistance: For some easily oxidised metals, such as aluminium, passivation can effectively prevent oxidation of its surface and maintain its luster and performance.

3、Extend the service life: by reducing corrosion and oxidation, passivation can significantly extend the service life of metal materials, reduce the frequency of repair and replacement.

4、Improve surface properties: passivation can also improve the smoothness and adhesion of the metal surface, which helps the subsequent application of coatings and paints.

5、environmental advantages: passivation process usually does not use hazardous substances, help reduce the impact of industrial production on the environment, in line with the concept of sustainable development.

Passivation steps

Pre-treatment: Before passivation, aluminium needs to be cleaned and degreased to remove surface dirt and grease and to ensure that the passivation solution acts evenly on the surface of the aluminium.

Passivation: Cleaned aluminium is immersed in a passivation solution or placed in an electrolytic bath for electrochemical passivation. Parameters such as the composition, concentration, temperature and treatment time of the passivate or electrolyte affect the quality and performance of the passivated film. Therefore, it is necessary to select the appropriate passivation process parameters according to the specific situation.

Post-treatment: After the passivation is completed, the aluminium needs to be cleaned and dried to remove any residual passivation solution and moisture from the surface. At the same time, a sealing treatment can also be carried out to further improve the corrosion and wear resistance of the passivated film.