Mullite Sand

The mullite sand commonly has diameters of 8-16 meshes, 16-30 meshes, 30-60 meshes, 60-80 meshes and 80-120 meshes; and the mullite powder commonly has diameters of 200 meshes, 300 meshes and so on.

In the precision casting process,

Common surface layer slurry: zircon powder 325 meshes+silica sol sand: zircon sand 120 meshes

Back layer slurry: zircon powder 325 meshes+silica sol+mullite powder 200 meshes sand: mullite sand 30-60 meshes

Reinforced layer: mullite powder 200 meshes+silica sol sand: mullite sand 16-30 meshes

Sealing slurry: mullite powder 200 meshes+silica sol

Common Chemical Components: 46%≥Al2O3≥42%, 53%≥SiO2≥51%, 1.2≤Fe2O3≤1.5%, Na2O+K2O≤0.3%, CaO+MgO2≤0.6%, TiO2≤0.1%

Physical Indexes: density≥2.5g/cm3, true specific gravity>2.6g/cm3, water content<0.03%, refractoriness≥1,750℃, ignition loss≤0.3-0.4%, dustiness≤0.01-0.03%, pH value=7-9, shell hardness>8.0Mpa

Advantages: castings are easily unshelled, not deformed and difficultly shrunk and have good finish and high yield.