Refractory dense aggregate, also known as refractory aggregate, is a kind of aggregate used as a main material in the production of refractory castable, gunning and ramming materials.Refractory aggregate is usually composed of magnesia, corundum, silica, mullite, and so on, with certain pressure and Mohs hardness, high refractoriness and good thermal stability.
Refractory dense aggregate is classified according to the shape of its particles. The common categories are sintered corundum, fused mullite, sintered silica, fused zirconia, periclase, silicon carbide and so on. Among them, corundum and fused mullite have the highest degree of refractoriness and thermal stability.
The main functions of refractory dense aggregate are:
1. Refractory dense aggregate can improve the density of high-grade refractory castables. After the combination of refractory aggregates, some space can be left betwxe homogeneous particles, and the inter particle gap will increase the permeability of high-grade refractory castables.
2. Refractory dense aggregate can improve the volume stability of the castable, reduce the coefficient of thermal expansion, avoid deformation and cracking during use, reduce the thermal shock resistance, and improve the product quality.
3. Refractory dense aggregate can enhance the structural strength of refractory castable materials, improve mechanical strength, and improve its performance in use.
When using refractory dense aggregate, it is necessary to pay attention to matters such as fineness and sintering temperature. If the fineness of material is too coarse, it will affect the permeability; if it is too fine, the resistance to wear and tear of refractory castable will also be reduced. In addition, the sintering temperature of the material should also be strictly controlled. If the sintering temperature is too low, the performance of the refractory castable will be reduced.
In a word, refractory dense aggregate is the main raw material for the production of high-grade refractory castables, and it plays an important role in improving the performance of refractory castables, such as density, thermal shock resistance, strength, wear and tear resistance, etc. It is also essential to pay attention to fineness and sintering temperature in the process of use.
