Self-healing Metal Oxide
Definition - What does Self-healing Metal Oxide mean?
A self-healing metal oxide is a type of oxide layer that is able to repair itself upon being damaged. It can do so because of the unique physical properties it possesses. When the metal oxide is able to self-heal, it can continue to prevent corrosion of the underlying base material.
Corrosionpedia explains Self-healing Metal Oxide
A self-healing metal oxide can be a tenacious material such as aluminum oxide or chromium oxide. In contrast, a metal oxide such as iron oxide, or rust, is not considered self-healing because it is not tenacious and is often detrimental. Aluminum oxide and chromium oxide are unique in the way that they are able to prevent corrosion of an underlying substrate. These self-healing oxides are what make aluminum and stainless steel corrosion-resistant.
Self-healing coatings work because of several physical characteristics. They are thin, with a thickness measured in nanometers. This, in some part, plays a role with how they self-heal. The self-healing occurs because when the oxide layer is damaged the metal oxide is able to flow in a fashion similar to a liquid over the damaged area. Aluminum oxide, when applied in a very thin layer, can even deform to a length double the original measurement.