Thermal spray coatings are a method of surface modification in which
various metallic and non-metallic materials are sprayed in molten, semi-molten, or
even solid state on a prepared substrate. The coating material is present in two forms:
wire or powder. The most common thermal spraying techniques include cold spray,
electric arc spray, plasma spray, detonation gun spray, flame spray, and high-velocity
oxy-fuel spray. The coating's thickness, which is calculated in millimeters or microns
and has distinguishing features from the base material's surface, is acceptable in many
industrial sectors and is ideal for on-site industrial applications. These processes also
offer affordable solutions in many industrial sectors and are capable of providing
surface modification approaches with enhanced surface properties comprising better
texture and high mechanical strength in terms of hardness, scratch resistance, and
porosity. This chapter presents the evolution of coatings developed during the last few
decades using various coating processes and materials for the protection of service
components. Coating measures are developed for use in thermal power plants, gas
steam, and the automotive industry for the treatment of components, able to work in
harsh environments of flue gases and chemicals.
Keywords: Coating evolution, Cold spraying, Coating structure, Coating thickness, Flame Temperature, Feedstock material, Oxidation resistance, Particle velocity, Surface treatment, Surface modification, Thermal power plant, Thermal spray coatings.
