Manganese phosphate coating

A type of coating applied to the surface of metals, especially steel. It is formed by a chemical reaction between the metal surface and a solution of manganese phosphate. Manganese phosphate coating has a darker coating of black or dark gray compared to zinc phosphate.

Properties of manganese phosphate

1- High corrosion resistance: This phosphate has better corrosion resistance than iron phosphate, especially in humid and salty environments.

2- Coating thickness: The manganese phosphate coating is usually thicker than iron phosphate.

3- Good adhesion: It adheres to the metal surface, thus providing better protection against corrosion.

4- Dark color: The dark color provides a certain aesthetic appearance, although this may not be desirable in all applications.

Application

It is widely used in various industries:

-Automotive: For coating automotive parts such as bolts, springs and other metal parts that require resistance to corrosion and wear.

-Home appliance industry: In coating metal parts of home appliances such as refrigerators, washing machines and gas stoves.

-Aerospace: For coating metal parts against corrosion and wear in harsh conditions

-Construction industry: For coating metal parts exposed to moisture and corrosion.

Comparison with other phosphates

Compared to iron and zinc phosphate, it has higher corrosion resistance, but is usually more expensive and the coating process is more complex.