What are the basic processes of thermal spraying?

       The basic process of thermal spraying includes: substrate surface pretreatment, spraying, surface heat treatment and coating sealing treatment, finishing of coating surface.



(1) Substrate surface pretreatment: After selecting the spraying method, the pretreatment process must be selected, including degreasing, rust removal, and surface roughening.



(2) Spraying: During spraying construction, reasonable process parameters must be determined to control the spraying quality.



Including: ① spraying heat source conditions, that is, the type of fuel and the ratio of mixing with oxygen;



②Material conveying, that is, the type, speed, flow rate and conveying position and angle of conveying gas;



③ Spraying materials, including material composition, physical properties, powder shape, particle size, wire or rod diameter, etc.;



④Substrate composition, substrate temperature, performance, and surface treatment method of mechanical parts; ⑤Spraying operations, including the distance between the spray gun and the machine parts, the moving speed of the spray gun or the machine parts, the angle between the spray gun and the machine parts, and the spraying gas medium, etc. .



(3) Post-coating treatment: Sealing treatment or heat treatment should be carried out immediately after painting.



(4) Finishing: After spraying, the coating needs to be polished to ensure dimensional accuracy. In addition, attention must be paid to safety protection during spraying construction.

Including: preventing the harm of high-speed and high-temperature jet jets to personnel and equipment; dustproof and ventilation of spray dust; safety protection of spray noise and spray arc radiation.