White aluminum oxide # 36 # 30 # 24 for mold steel sandblasting
Mold steel is usually alloy steel containing multiple elements. It always goes with high-speed steel or carbon steel containing chromium, nickel, manganese, and molybdenum. Users have to choose the proper blasting media for blasting those steels. White aluminum oxide coarse grits such as # 36 mesh # 30 mesh # 24 mesh can efficiently grind and surface treat mold steel.
The main component of white aluminum oxide is α-Al2O3. The hardness of WFA is Mohs scale 9.0 & Vickers scale 22-24Gpa. It ranks behind the diamond, Boron carbide, and silicon carbide. Meanwhile, the toughness of white aluminum oxide is higher than that of silicon carbide. It is not fragile and less prone to breakage when grinding metals and steel.
During the processing of mold steel, there are two necessary blasting steps.
- Blasting treatment after spraying primer. White aluminum oxide can remove the attachments and oxides easily.
- Blasting and etching after heat treatment annealing. White aluminum oxide can make the passivation more effective.
In addition, after sandblasting with white aluminum oxide, there will be no magnetic residue on the surface of the steel. After sandblasting with white corundum, the surface roughness of the mold steel increases. It is beneficial for improving the adhesion of the subsequent spray coating, durability, hardness, and corrosion resistance. Moreover, the purity of white aluminum oxide is high, it can be used for sandblasting of molds in contact with food, equipment in the pharmaceutical industry, and components in the aerospace industry. It can prevent pollution on mold surfaces.
