Components in aircraft, automobile, power plants, chemical reactors and etc are frequently exposed to sever heat, abrasion, and corrosion. A thin surface coating of a suitable material such as ceramic or super-alloy is often the best way to protect an extend the life time of such components. Thermal spray coating technology is used extensively as an efficient, economical, and environmentally friendly method of applying coatings for a wide range of industrial applications. In an ideal thermal spray process, powders or wire feedstock are fed into a high velocity, high temperature gas jet generated by a oxy-fuel combustion or an electric arc (plasma). Feeding powders are melted and accelerated toward the substrate of mandrel mold. The in-flight particles have various temperature and velocity distributions upon impact. Finally, the droplets solidify after impacting the substrate. Solidification occurs at rates similar to those obtained in rapid solidification technology. Thus the as-sprayed deposit is ultra-fine grained. having the properties associated with such microstructures. The materials which are sprayed include most metal alloys and ceramics. Thermal spray deposits can be used in wear and corrosion resistance applications and
also in thermal barrier coating for high temperature oxidation resistance applications. Thermal spray technologies give much higher deposition rates than other chemical or physical vapor deposition techniques, and create few environmental problems. They can be used to coat components varying in size from a few millimeters to several meters.
