Definition - What does Protective Coating mean?
A protective coating is a layer of material applied to the surface of another material with the intent of inhibiting or preventing corrosion. A protective coating may be metallic or non-metallic. Protective coatings are applied using a variety of methods, and can be used for many other purposes besides corrosion prevention.
Commonly used materials in non-metallic protective coatings include polymers, epoxies and polyurethanes. Materials used for metallic protective coatings include zinc, aluminum and chromium.
Corrosionpedia explains Protective Coating
A zinc coating over steel is an example of a reactive protective coating. The zinc reacts with the atmosphere more readily than the steel, thus preventing the oxidation of the steel.
A protective coating can be painted on, sprayed on, plated on or even welded onto a material. Polymer coatings are commonly sprayed on. Zinc protective coatings are typically applied by the electroplating or hot dipping method.
A protective coating is not necessarily limited to corrosion prevention. A protective coating can also be used to increase a material's wear resistance and aesthetic appeal. A protective coating can provide water resistance or electrical properties that the material did not have prior to the protective coating being applied.