Product Performance;

The alumina powder used for thermal spraying is high-purity α-Al2O3 obtained through smelting and crushing. The α-Al2O3 crystal form is the most stable hexagonal structure among various polymorphs, exhibiting good thermal cycling resistance.

Aluminum oxide possesses strong dielectric properties, high refractoriness, resistance to acids and alkalis, stable chemical performance at high temperatures, wear resistance, resistance to high-temperature erosion, and resistance to sliding wear. It can be widely used as thermal insulation coatings, high-temperature resistant coatings, wear-resistant coatings, and insulating coatings, with an operating temperature of <1650°C.

Product Applications

Recommended components for textile machinery that require resistance to fiber wear; bearing insulating housings, motor rotor insulating bearing seats, etc.; in the electronics industry, Al2O3 ceramic coatings are used as substrates for integrated circuits and high-performance packaging materials.

When applying thermal insulation coatings, nickel-chromium alloy or nickel-clad aluminum should be used as a transition layer to enhance bonding strength and protect the substrate from oxidation or corrosion. For wear-resistant coatings, the spraying power should be increased during application to ensure complete melting of the powder, reduce porosity in the coating, and improve hardness, enabling the grinding and processing of surfaces with low roughness. As a high-temperature resistant coating material, it can be used in applications such as blast furnace tuyeres and slag notches to extend their service life; in rocket and jet engine nozzles to prevent erosion from high-temperature gas jets; and also to protect against chemical media corrosion.

Alumina coatings cannot withstand impact loads or localized collisions, as this may cause damage and peeling of the coating. To improve the performance of alumina and enhance the density of the coating, it is often mixed with titanium oxide or compounded with nickel-aluminum, resulting in better toughness and impact resistance compared to pure alumina coatings. For example, coatings made by adding a certain amount of TiO2, Cr2O3, or SiO2 to alumina do not undergo phase changes due to heating and cooling. Therefore, the overall performance and thermal cycling resistance of the coating and the workpiece substrate can be improved.