The passivation principles are based on electrochemical kinetics, which results from the formation of protective films on the metal surface by imposition of currents. Passivation is used to ensure the corrosion resistance of the component or part and, consequently, its durability. The passive layer that develops on stainless steel is not a simple layer or oxide, like the one that is formed when the material is heated. Parts intended for applications at temperatures close to the environment have a passive, thin and transparent layer for their resistance to corrosion.
Although this passivation process occurs naturally, it can be induced through the action of strongly oxidizing acids. Nitric acid is one of the most widely used reagents for this purpose in commercially available passivation treatments for stainless steels. Weaker acids, such as citric, can also assist in the formation of the passive layer.
Passivation is the modification of the potential of an electrode towards less activity (more cathodic or more noble) due to the formation of a corrosion product film.
| Treatment Description | Treatment Code | Classification | Layer |
| STAINLESS CHEMICAL PASSIVATION | PAQU-IN | TYPE I | 0 |
