Thermal spraying is a process in which metallic and non-metallic materials are deposited in a molten or semi-molten form on a prepared component surface to optimise its characteristics and to protect against wear, corrosion and erosion.

Since many metals, alloys, carbides, ceramics, plastics, and combinations can be applied in the process, its potential is almost limitless. Using a thermal spray process, the material is melted by electric arc or combustible gas, then kinetic energy or a compressed gas stream atomizes the material and carries it to the base (substrate) material. As the particles strike the surface, they flatten, adhere and conform to the irregularities of the surface. Upon impact with the substrate material, these flattened particles cool and build up to form a coating.

Many parts and components, new or used, can have their performance improved and enhanced, and thereby result in cost savings through lengthened part life. Parts may also be enhanced with unique traits using thermal spraying. Worn and corroded parts, which would otherwise be scrapped, can be reclaimed using a thermal sprayed coating. The part can be brought back to specification again and again yielding considerable savings over time.

Though very high temperatures are necessary to melt the material prior to spraying, the component being coated is actually subjected to very little heat, less than 300 °F. This allows the use of many different substrate materials and alleviates damage to the component material.