Item | Dense zircon brick | Zircon brick | zirconium -corundum brick | Zirconium -mullite brick | Semi- zircon brick |
ZrO2 % | ≥65 | ≥60 | ≥30 | ≥18 | ≥15—20 |
Al2O3 % | — | — | ≥45 | ≥55 | ≥50—60 |
SiO2 % | — | ≤38 | ≤25 | ≤25 | ≤20 |
Fe2O3 % | ≤0.3 | ≤0.5 | ≤0.5 | ≤0.5 | ≤1.2 |
Apparent porosity % | ≤18 | ≤22 | ≤20 | ≤17 | ≤20 |
Bulk density g/cm3 | ≥3.7 | ≥3.5 | ≥3.2 | ≥2.7 | ≥2.7 |
Cold compressive strength MPa | ≥100 | ≥100 | ≥100 | ≥100 | ≥100 |
Refractoriness under load °C | ≥1650 | ≥1620 | ≥1650 | ≥1650 | ≥155 |