What is the primary purpose of using a conversion coating in metal treatment?

The primary purpose of using a conversion coating in metal treatment is to improve adhesion and corrosion resistance. Conversion coatings are chemical treatments that alter the surface of a metal substrate, creating a layer that enhances the bond between the metal and subsequent coatings, such as paint or primer. This helps prevent peeling and improves overall durability.

Additionally, conversion coatings, such as chromate or phosphate treatments, act as a barrier against environmental factors that can lead to corrosion. By effectively protecting the metal surface from moisture and contaminants, these coatings significantly contribute to extending the lifespan of metal products in various applications.

While sealing the metal surface, providing a decorative finish, or enhancing electrical conductivity can have their own merits in specific contexts, the fundamental role of conversion coatings is primarily centered around improving adhesion and offering corrosion resistance, making it crucial for automotive parts and other metal components exposed to harsh conditions.