AF-T Series
AF-T tabular alumina is produced by sintering high-purity calcined alumina at temperatures approaching 1900°C in vertical shaft kilns. The resulting product features large, well-developed tabular (platelet-shaped) alpha-Al₂O₃ crystals with low open porosity, high bulk density, and exceptional thermal shock resistance. Available in multiple size fractions for optimal particle packing in refractory formulations.
| Parameter | AF-T-1 | Typical |
|---|---|---|
| Al₂O₃ | ≥ 99.4% | 99.5% |
| Na₂O (total) | ≤ 0.25% | 0.15% |
| Fe₂O₃ | ≤ 0.05% | 0.03% |
| SiO₂ | ≤ 0.10% | 0.06% |
| CaO | ≤ 0.06% | 0.03% |
| Alpha-Al₂O₃ | ≥ 98% | 99% |
| Parameter | AF-T-1 |
|---|---|
| Bulk density (pellets) | ≥ 3.50 g/cm³ |
| Apparent porosity | ≤ 5.0% |
| Water absorption | ≤ 1.5% |
| Refractoriness (PCE) | > 1850°C (Orton cone 39+) |
| Thermal expansion (20–1000°C) | ~8.0 × 10⁻⁶ /K |
| Thermal conductivity (400°C) | ~6 W/(m·K) |
| Grain shape | Tabular (platelet) |
| Fraction | Size Range | Typical Use |
|---|---|---|
| K1 (fine) | 0–0.5 mm | Matrix fines, low-cement castables |
| K2 (medium-fine) | 0.5–1.5 mm | Intermediate aggregate |
| K3 (medium) | 1.5–3.0 mm | Coarse aggregate, slide gates |
| K4 (coarse) | 3.0–5.0 mm | Coarse aggregate, purging plugs |
| Pellets | > 6 mm | Crush-to-size for custom fractions |
| Fine grades | D50 7–40 μm | Micro-filler, available on request |
Optimal packing in refractory castables is achieved with a modified Andreasen or Dinger-Funk distribution (q = 0.26–0.30). Typical aggregate blend: 40% K3/K4, 25% K2, 20% K1, 15% fines (<45 μm). Contact our technical team for formulation support.
Non-hazardous under REACH and OSHA HCS. Avoid dust inhalation — use local exhaust ventilation. Coarse fractions pose low inhalation risk; fine fractions (<45 μm) require standard dust protection. Full SDS available on request.