Home/Technical Glossary/Passivation of Stainless Steel Passivation of Stainless Steel Passivation is a chemical treatment with a specific acid formulation that removes free-iron or other surface contamination from stainless steel while simultaneously promoting the formation of a passive chromium/nickel oxide layer to act as a barrier to further corrosion. Passivation is necessary to remove embedded contaminants and return the part to its original corrosion specifications. Though passivation can improve the corrosion resistance of certain stainless steel alloys, it does not eliminate imperfections like micro cracks, burrs, heat tint and oxide scale. Passivation resistant laser marking is the process of creating a laser mark that does not affect the corrosion resistant property of the material yet is not removed during the passivation process.