Chemical Composition of Fused Ceramic Sand
Composition | Al2O3 | FeO3 | SiO2 | TiO2 | CaO | MgO | K2O | Na2O |
％ | 72.56 | 2.23 | 19.86 | 3.53 | 0.43 | 0.35 | 0.78 | 0.08 |
Ceramic Foundry Sand Features or Advantages as Follows:
1. Round solid ball shape, saving binder addition
2. High refractoriness and service temperature
3. Good air permeability
4. Lower thermal expansion rate and thermal conductivity
5. Lower bulk density, lower true specific gravity and lower specific surface area
6. Standard particle sizes
7. Easily reclaimed and lower breakage rate during dry crushing
8. Single application, no need mix with other foundry sands
9. To reduce pollution and protect environment.
Analysis of Sand Sticking Prevention of Using Fused Ceramic Sand
1. Mechanical sand sticking is the result of interface reaction between molten metal and mold. After the molten metal is injected into the mold, a series of physical, chemical and physicochemical reactions will take place between the molten metal, mold materials and gas in the mold at the interface. Sand sticking is the comprehensive result of many functions.
Fused ceramic sand is spherical with good fluidity, and it is easy to fill at the corner of the inner cavity. The surface is smooth and the structure is compact, so that the binder can be evenly covered, and it is easy to obtain high compactness, that is to say, it reduces the pore radius between sand particles, thus increasing the critical osmotic pressure, and the metal is not easy to penetrate, preventing the mechanical penetration of sand.
2. Chemical sand sticking is the chemical reaction between SiO2 in silica sand material and FeO in molten steel at the metal / mold interface to produce low melting point iron silicate (fe2si204). The salt generated by the above reaction adheres to the casting surface and forms a sticky sand layer that is difficult to remove.
Fused ceramic sand has high refractoriness (up above 1790℃) and good chemical stability at high temperature. It is a neutral material. Among them, Al2O3 is not easy to react with iron oxide, and will not generate low melting point salts. The core sand is dense, and the surface prevents the infiltration of molten steel, which can prevent the generation of chemical sand.
Conclusion on the Use of Fused Ceramic Sand
Fused ceramic sand can replace chrome ore sand in the sand sticking part of high manganese steel casting core. On the one hand, it can well complete the role of molding sand, on the other hand, it can bring considerable economic benefits.