Definition - What does Inhibitor Coating mean?
An inhibitor coating is a material that coats a metal surface, providing a protective barrier film, which in turn stops a corrosive reaction from occurring. It is used for decreasing the corrosion rate of a material, typically a metal or an alloy.
Previously, the most effective corrosion inhibitor coatings were oil- or solvent-based materials. Now water-based products are also used with success for corrosion inhibitions.
Corrosionpedia explains Inhibitor Coating
Inhibitor coatings involve formation of a coating, often a passivation layer, which prevents access of the corrosive substance to the metal. Chromate-type pigments are an example of this mechanism.
Considerations when selecting inhibitor coatings:
- Materials to be protected
- Protection time frame
- Method of application (dip, spray, brush, etc.)
- Storage, packaging and/or shipping conditions
- Removal methods
- Oil, solvent or water based
Oil- and solvent-based inhibitors rely principally on the formation of barrier coatings to prevent water from contacting metal surfaces. The protective coating they form varies (semi-hard,soft, oily, transparent, colored) with the specific product, and the coatings can be applied by brush, dip, and spray methods. These inhibitors are preferred for longer protection due to their heavy film and their water-repellent properties.
Water-based inhibitors rely on modifying the characteristics of the metal surfaces themselves to decrease their susceptibility to oxidation and corrosion formation. Application methods for these coatings include spray, brush or immersion, and the chemical films formed are thin and typically transparent when dry. Water-based inhibitors have a long lifespan under normal conditions. They are less costly than most oil/solvent-based products.