Due to the variety of thermal spray materials and the wide range of applications, how to properly select thermal spray coatings when designing products and repairing parts is related to the success or failure of the workpiece. Therefore, according to the performance of the coating under the working conditions of the workpiece, the physical and chemical properties of the sprayed material and the matrix material, carefully evaluated, combined with the application technology of the coating, and careful testing can be finally determined. The thermal spraying of Evergreen metal mainly considers the following factors:
(1) Possibility of technological methods
For example, in terms of the use requirements of the parts, it is appropriate to spray the nickel-based self-fluxing alloy and then perform the melting treatment, but for some reason (such as the parts are deformed by heat, electroplated or protected with organic coatings Withstand the melting temperature of the coating, etc.) This process cannot be used. When selecting the process method, the mechanical processing performance of the sprayed layer should also be considered, and the mechanical processing method, which mechanical processing method is adopted, and the processing cost, etc. should be considered according to the size and shape of the part.
(2) Working environment
Including the stress or impact of the coating in the work, the working temperature, the corrosive medium and the corrosive environment, the material and lubrication of the surface of the coating and other parts and the connection surface, etc.
(3) Required coating characteristics
Including the surface function of the coating, such as surface state, surface finish, chemical properties of the coating, adhesive strength, porosity, hardness of the coating, corrosion resistance, wear resistance, friction performance, electrical performance, heat resistance of the coating And thermal conductivity, coating thickness and finishing performance.
(4) Characteristics of matrix materials
The size and shape of the sprayed parts, the surface condition of the sprayed parts, the density and quality of the parts, the sensitivity of the base material to temperature, the chemical composition, hardness, thermal expansion coefficient of the base material, the stress state in the parts, whether the parts are before thermal spraying Other surface treatments have been carried out.
