Passivation treatment is a chemical process that improves the metal's corrosion resistance by creating a thin, protective oxide film on its surface. This process is usually used for stainless steel and other metals to prevent rust. Passivation treatment typically involves treating the metal surface with a solution, such as nitric acid or citric acid, to remove surface impurities and contaminants, allowing a natural protective oxide layer to reform.
Purpose
Passivation treatment aims to create a passive, or inert surface on a metal, making it less acceptable to chemical reaction that can lead to corrosion.
Principle
The core of passivation treatment is to create a thin, dense film on the surface of metals. The film is usually created by the reaction between metal and oxidizing medium, and has the characteristics of being very thin and dense. It can firmly adhere to the surface of the metal, thereby isolating the direct contact between the metal and the corrosive medium and significantly reducing the corrosion rate.
Application fields and specific methods
Passivation treatment is widely used in various types of stainless steel parts, plates, and equipment. The specific methods include acid pickling, water rinsing, and rinsing, etc. For example, comprehensive acid pickling and passivation treatment of stainless steel can remove various types of oil stains, rust, oxide scales, welding spots and other dirt. Passivation treatment can significantly improve the corrosion resistance of stainless steel.
