Powders, Wires, and Cords

Powders, wires, or cords are the key components on which the quality of the coating obtained using thermal spray strongly depends. As discussed throughout this book, Thermal Spray Technology centers around the use of mechanical, chemical, or electrical energy to develop a high energy gas stream in which the material to be sprayed is injected in the form of a powder, wire, cord, suspension, or solution. On contact with the high energy spraying medium which transforms the injected material into a high energy spray of individual particles or molten droplets that are entrained by the process gas and projected against the substrate forming splats. The coating is formed through the layering of these splats with strong adhesion to the surface of the substrate and the required microstructure for its functional role whether it is for wear or corrosion protection, thermal protection, or any of other functional properties.