Black silicon carbide

 White fused alumina (high purity with Al₂O₃ content over 99%) is produced from high purity alumina in electric arc furnaces at temperatures over 2000℃ under carefully controlled conditions.
 White fused alumina is also characterized by high hardness of mohs 9, the chemical stability at very high temperatures, great self-sharpening, superior acid and alkali resistance, and stable thermal performance.
 Physical Index:
True density 3.96g/ cm³
Hardness 2000~2200kg/ mm²
Refractoriness ≥1850℃
Max useable temperature 1900℃
 Chemical composition:
 Al₂O₃ ≥99.20 and Na₂O≤0.40 in F12-220;
 Al₂O₃≥99.00 and Na₂O≤0.50 in F230-400;
 Al₂O₃≥99.00 and Na₂O≤0.50 in F500-1200;