2, the principle of thermal spraying: thermal spraying refers to a series of processes, in these processes, fine and dispersed metal or non-metallic coating material, in a molten or semi-molten state, deposited on a prepared substrate surface , To form some sort of spray deposit. The coating material can be in the form of powder, ribbon, filament or rod. Thermal spray guns provide the necessary heat from the fuel gas, arc or plasma arc to heat the thermal spray material to the plastic or molten state and then subject to compressed air acceleration to impinge the constrained particle beam onto the substrate surface. Particles impinging on the surface are deformed by stamping to form laminated sheets that adhere to the surface of the prepared substrate and subsequently cool and accumulate to form a layered coating. The coating due to the different coating materials can achieve high temperature corrosion, abrasion, heat insulation, anti-electromagnetic wave and other functions.