Is through a heat source, thermal spraying technology will some material heated to melt or half molten state, and then into the coating of the surface of the substrate, forming a layer of coating performance is better than that of the original matrix, which makes the original artifacts has more excellent surface properties, or make the workpiece material with one or several of the original substrate does not have the surface properties of membrane organization. These surface properties including wear-resisting, corrosion resistance, heat resistance, oxidation resistance, heat insulation, insulation, conductive, seal, disinfection, microwave radiation, and other various special physical and chemical properties.At present, thermal spraying technology has been widely used in many fields, including aviation, aerospace, atomic energy equipment, electronics and other cutting-edge technologies, and has achieved good economic benefits.
Spraying materials include metals, ceramics and plastics.The formation of spraying layer includes the heating and melting stage of spraying material, the atomizing stage of melting droplets, the flying stage of particles and the spraying stage of particles.The combination of coating and matrix includes mechanical bond, diffusion bond, physical bond and metallurgical bond.When using exothermic spraying material or using high temperature heat source spraying, the molten spraying material particles will produce welding phenomenon with the molten matrix, forming a micro metallurgical bond, and improving the bonding strength of the coating and the matrix.The bonding between particles in the spraying layer is mainly mechanical bonding, while diffusion bonding, physical bonding, metallurgical bonding and so on also work together.