What’s the properties of Silica Brick
Silica brick properties:
1. Fire resistance and load softening temperature
The fire resistance of silica brick is generally 1690 ~ 1730 ℃, and the load softening temperature of silica brick is high, about 1650 ℃. The load softening temperature and fire resistance of silica brick are close, which is mainly because the main crystal phase of silica brick is scale quartz with spearhead bicrystal to form network structure and the matrix is glass phase with high viscosity.
2. Slag resistance
Silica brick is an acid refractory, which has strong resistance to the corrosion of acid and weak acid slag and corrosive gas.
3. High temperature volume stability
During the heating process, the silica brick not only has certain thermal expansion, but also has crystal transformation and volume expansion. If there is unconverted residual quartz in the brick, it will continue to change into scaly quartz or cristobalite at high temperature, resulting in large volume expansion.
4. Thermal shock stability
The thermal shock resistance of silica brick is poor, and the water cooling is only 1 ~ 2 times at 850℃. The reason is that the silicon brick will undergo crystal transformation during high temperature quenching, resulting in large volume change. This is a big weakness of silica brick.
Silica brick is an acidic refractory, which has strong resistance to the corrosion of acidic slag or acidic molten liquid, but has poor resistance to the corrosion of alkaline substances. It is easy to be damaged by oxides such as Al2O3, K2O and Na2O, and has good resistance to oxides such as Cao, FeO and Fe2O3.