Tabular alumina is pur α-alumina resulting from intensive sintering at temperatures exceeding 1,800 °C, without sintering additives. Low temperature expansion and high heat resistance can be explained by the microstructure specifics: low effective porosity and large sizes of crystals with closed spherical pores resulting from intensive sintering.
Style(Item)
| chemical index | physical index | |||||
Al2O3(%) | SiO2(%) | Fe2O3(%) | Na2O(%) | Volume density (g/cm3) | water absorption(%) | apparent porosity(%) | |
0-1mm 1-3mm 3-5mm 5-8mm |
99.3 min |
0.1 max |
0.08 max |
0.4 max |
3.5 |
1.5 |
5 max |
200#-0 320#-0 325# | 99.1 min | 0.15 max | 0.1max | 0.4 max | 3.45 | 2.0 | 6 max |
Tabular alumina has exceptionally high refractory properties, mechanical strength, wear resistance, chemical purity, dielectric properties, and excellent corrosive resistance in acid and alkaline environments.
The tabular alumina manufacturing process implies performance of the quality assurance and control at each production stage. This is necessary for the production of superior-quality products. From feeding raw materials to sintering in a shaft furnace at the temperature above 1,800°C, the production process monitoring and control is provided by the skilled personnel and the automated machinery system.
Sintered tabular alumina spinel granules are subject to crushing and classification. Efficient roll crushers and vibratory screens are used for this purpose. To reduce the amount of magnetic iron to standard permissible levels (0.025%), all tabular alumina grading fractions undergo magnetic separation.
The fine grinding area has been purchased and is continuously used for the production of tabular alumina fine fractions. This area includes a highly-efficient ball mill with a separator. All surfaces of the mill and material ducts are lined with wear-resistant ceramics to reduce the amount of magnetic iron in the finished products.
