1. Physical Properties
Water absorption ≤2 %
Acid resistance ≥98 %
Alkali resistance ≥80 %
Thermal resistance ≥1300 ℃
Roundness (Dmax/Dmin) < 1.25
Volume 40~50 %
Material density 2.2~2.4 g/cm3
BET-surface < 0.1 m2/g
Expansion coefficient 4.7 x 10-6 L/K
Spec. thermal energy ~0.84 kJ/(kg.K)
Thermal conductivity ~0.63 m. h.K
Mohs-hardness ~8 Mohs

2. Chemical Composition
Al2O3 >23 %
SiO2 67~69
Al2O3+SiO2≥90 %
Fe2O3 ≤1 %