Manganese phosphating is used as a coating when good corrosion protection is needed. It also acts as a base for oils, rust inhibitors, waxes and paints.
The surface treatment aids in cold working and deep drawing of steel. The coating is technical and is black in colour.
Manganese phosphating is a chemical treatment of steel in which the metal surface reacts with a bath solution to form a thin, fine crystalline coating of manganese phosphate. The chemical treatment allows the manganese phosphate to penetrate the surface of the piece uniformly. The pieces are oiled as a post-treatment.
Manganese phosphating prevents friction on surfaces that rub against each other, e.g., gears, pistons and piston rings.
The treatment is done by rack or barrel coating methods in automated lines.