What material can be used for sandblasting aluminum castings?
Aluminum castings refer to pure aluminum or aluminum alloy equipment and components obtained by casting. Generally, a sand mold or a metal mold is used to pour heated liquid aluminum or aluminum alloy into the mold cavity to obtain aluminum parts or aluminum alloy parts of various shapes and sizes.
Because aluminum castings tend to produce some burrs and bubbles during the casting process, these defects not only affect their appearance, but also have a negative impact on their mechanical and electrical properties. Therefore, before machining aluminum castings, it is usually necessary to sandblast the surface.
For sandblasting aluminum castings, the following materials are usually used:
Brown corundum : Because of its moderate hardness, stable chemical properties, low cost, good grinding effect and cost performance, it is a common choice in the aluminum casting sandblasting process.
White corundum: It has high hardness and corrosion resistance and is suitable for deep cleaning and rust removal. It can also be used for surface polishing and texture improvement.
Glass beads: It is suitable for aluminum alloy sandblasting, which can effectively remove surface oxide layer, dirt and minor scratches without causing obvious scraping or deformation of aluminum alloy.
Silicon carbide: Suitable for surface treatment of aluminum castings with certain special requirements, providing finer cleaning and polishing effects, but attention needs to be paid to controlling sandblasting pressure and operating techniques to avoid scratches.
Steel shot/steel grit: it has high hardness and long service life and is suitable for surface regrinding to remove surface defects and oxides. However, the grinding effect is relatively hard and may cause scratches on the surface of aluminum castings.
The choice of material depends on the material, surface condition and processing requirements of the part, as well as the user’s cost budget.
