Mullite brick introduction
Mullite (3Al2O3, 2SiO2) high aluminum refractory material as main crystalline phase.
General alumina content in 65% ~ 75%. Mineral composition in addition to mullite, alumina containing lower also contain a small amount of glass phase and cristobalite;
Alumina containing higher also contain a small amount of corundum
Refractory degree is high, can reach more than 1790 DEG C. Refractoriness under load was 1600 ~ 1700 DEG C. Compressive strength of 70 ~ 260MPa. Good thermal shock resistance.
Sintered mullite brick and fused mullite brick two. Sintered mullite brick with high alumina bauxite clinker as the main raw material, adding a small amount of clay or raw bauxite as binder, after molding, sintering and made
Electric cast mullite brick with high alumina, A12O3 and refractory clay as raw material, adding charcoal or coke fines as a reducing agent, after forming by reduction of electric melting method to manufacture. Crystal fused mullite than sintered mullite, thermal shock resistance than sintered products. Uniformity of content in the high temperature properties of alumina and mullite mainly depends on their distribution and glass.
Mullite brick Applications
| Item | MU60 | MU65 | MU70 | MU75 | |
| Chemical composition | Al2O3 | ≥60 | ≥65 | ≥70 | ≥75 |
| SiO2 | ≤35 | ≤33 | ≤26 | ≤24 | |
| Fe2O3 | ≤1.0 | ≤1.0 | ≤0.6 | ≤0.4 | |
| Apparent Porosity％ | ≤17 | ≤17 | ≤17 | ≤18 | |
| Bulk Density g/cm3 | ≥2.55 | ≥2.55 | ≥2.55 | ≥2.55 | |
| Cold Crushing Strength Mpa | ≥60 | ≥60 | ≥80 | ≥80 | |
| 0.2Mpa Refractoriness Under Load T0.6℃ | ≥1580 | ≥1600 | ≥1600 | ≥1650 | |
| Permanent Linear Change On Reheating（%）1500℃X2h | 0～+0.4 | 0～+0.4 | 0～+0.4 | 0～+0.4 | |
| Thermal Shock Resistances 100℃ water cycles | ≥18 | ≥18 | ≥18 | ≥18 | |
| 20－1000℃ Thermal Expansich10-6/℃ | 0.6 | 0.6 | 0.6 | 0.55 | |
| Thermal Conductivity (W/MK) 1000℃ | 1.74 | 1.84 | 1.95 | 1.95 | |