Coating

Coating is the application of a firmly adhering layer of shapeless material to the surface of a workpiece. 

A coating Coating Coating is the application of a firmly adhering layer of shapeless material to the surface of a workpiece. can be either a single layer or several layers. A distinction is made between chemical, mechanical, thermal and thermomechanical processes, depending on how the coating is applied. The thickness of the coating differs depending on the process and application purpose.