The principle and scope of application of supersonic arc spraying

       Supersonic arc spraying uses a Laval nozzle to increase the speed of the airflow from subsonic to supersonic, which enhances the acceleration effect of the airflow on the particles, thereby increasing the particle speed. Particle velocity has a large effect on the performance of the coating. The higher the particle velocity, the stronger the impact on the substrate when the particles are deposited, and the sufficient particle deformation. It is beneficial to the bonding between particles and substrates, particles and particles, thereby improving the bonding strength and cohesive strength of the coating; the particle velocity is high, the flight time of the particles in the air before deposition is short, and the oxides produced in the flight are less, It is beneficial to the bonding of particles, thereby improving the cohesive strength of the coating and reducing the porosity of the coating. The higher the particle velocity, the more favorable it is to obtain a high-quality coating. With the upgrading of thermal spray equipment, particle velocities continue to increase, and the quality of coatings continues to improve. Supersonic arc spraying: high-temperature corrosion-resistant, abrasive cermet coatings, high-chromium-nickel metal alloy coatings. Features: HRC>55-65, resistant to high temperature SO2, H2S, Na2SO4K2SO4 corrosion. Application: Coal-fired boiler, water wall, superheater, reheater. Working temperature >800℃, prolong the service life of workpiece for 6-8 years.