Definition - What does Additive mean?
An additive is a type of corrosion inhibitor that prevents the corrosion of a material when combined with a gas or a liquid. The gas or liquid containing the additive is applied to the material to reduce or eliminate the corrosive effects the material might otherwise have been subjected to.
An additive is applied to materials either to neutralize their corrosive abilities or to prevent a corrosive environment from reaching the material.
Corrosionpedia explains Additive
Although an additive can prevent corrosion by being applied to a material's surface, it should not be confused with a coating. However, an additive can be part of a coating formulation.
Additives are available in many different forms; it can be a liquid, a gas or a solid that is mixed with a liquid. An additive can be used to reduce the acidity of an environment. It can be used to inhibit the formation of rust. It can also be used to enhance the performance of petroleum products and in conjunction with a lubricant to perform two functions at once.