Passivation is intended to improve the corrosion resistance of parts made from austentic, ferritic and martensitic corrosion-resistant steels of the 200, 300 and 400 series and precipitation hardened corrosion-resistant steels. 440C grades may be exempt from passivation treatments at the discretion of the procuring activity. The types of passivating are alloy specific. A chemical treatment for stainless steeI that will improve corrosion resistance.
Passivation removes free iron and surface contaminant. The surface part is chemically cleaned to remove grease, dirt and treated by a mild acid. The treatment enhances the corrosion resistance of stainless steel. Testing to verify the effectiveness of the passivation treatment is usually accomplished by a salt spray test per ASTM-B-117.
Passivate Type II, VI, and VII.
Passivate per Mil-QQ-P-35