Why is foundry chromite sand used as the raw material for anti-sticking sand in cast steel?
The main reasons for using foundry chromite sand to prevent cast steel from sticking include its excellent physical and chemical properties. It’s mainly used as the surface sand of large steel castings in casting production, which can effectively prevent sand from sticking to the surface of castings. It has a stable heated volume and high thermal conductivity. When in contact with molten metal, it not only has a good effect of resisting alkaline slag, but also has the characteristics of solid phase sintering, which can well prevent the penetration of molten metal and avoid the occurrence of sticking defects.
Specifically, the following characteristics of foundry chromite sand make it excellent in anti-sticking:
Stable heated volume: Chromite sand has a small volume change when heated, maintains a stable shape, and is not easy to deform, thereby reducing the sticking phenomenon on the surface of castings.
High thermal conductivity: The thermal conductivity of chromite sand is much higher than that of silica sand, which can quickly conduct heat, increase the cooling rate of castings, and reduce the possibility of sticking.
Alkaline slag resistance: When in contact with molten metal, chromite sand has a good effect of resisting alkaline slag and can effectively prevent the penetration of molten metal.
Solid phase sintering: Chrome ore sand will solid phase sinter at high temperature to form a protective film, further preventing the penetration and sticking of molten metal.
These characteristics make chrome ore sand an ideal anti-sticking material in the production of steel castings, which can significantly improve the quality and yield of castings.
Chemcial data:
| Cr2O3 | SiO2 | FeO | CaO | MgO | Al2O3 | P | S | Cr/Fe |
| ≥46.0% | ≤1.0% | ≤26.5% | ≤0.30% | ≤10.0% | ≤15.5% | ≤0.003% | ≤0.003% | 1.55:1 |
Physical data:
| Bulk density | Volume density | colour | PH | calcined tempreture | smelting point |
| 2.5-3g/cm³ | 4.0～4.8g/cm3 | black | 7-9 | > 1800°C | 2180°C |
Package：1000kgs/jumb bag
Capacity：8000Tons/year
