Sintered Spinels
Sintered spinels are alumina and magnesia composites in different ratios. The high quality of the products is ensured by using alumina from own production, magnesia from verified sources and with detailed control of the production process.
During sintering, alpha-alumina crystals are combined with magnesia crystals to shape greater crystals, which give spinels a unified crystal structure, low porosity and high density. The use of spinels in magnesite and alumina refractory products increases their thermal shock and corrosion resistance. Silkem offers a broad range of sintered spinels, which are produced with crushing, grinding, mechanic and magnetic separation and the mixing of fractions.
Chemical Composition (%) | Spinel SP67 | Spinel SP78 | Spinel SP90 |
---|---|---|---|
(Typical) | (Typical) | (Typical) | |
Al2O3 | 67.0 | 78.0 | 90.0 |
MgO | 32.0 | 21.4 | 9.4 |
Na2O | 0.17 | 0.12 | 0.12 |
SiO2 | 0.13 | 0.10 | 0.10 |
Fe2O3 (Total) | 0.25 | 0.15 | 0.15 |
CaO |
0.45 |
0.20 | 0.20 |
Physical Characteristics1 | Min | Max | |
---|---|---|---|
Bulk Specific Gravity | (g/cm3) | 3.2 | |
Apparent Porosity | (%) | 1.2 | 2.6 |
Water Absorption | (%) | / | 1.0 |
1 For all three types of spinels
Standard grain size2
(mm) | (mesh) | (mm) | (mesh) |
---|---|---|---|
3–6 | 3–6 | 0–0.5/0.6 | –28 |
1–3 | 6–14 | 0–0.090 | –170 |
0–1 | –14 | 0–0.045 | –325 |
0,5/0,6–1 | 14–28 | 0–0.020 | –635 |
2 Other grain sizes are also possible