Fused cast corundum series can be divided into three groups according to differing alumina crystal forms and quantities: α corundum block with the main crystal phase of α-Al2O3; α,β corundum block with the main crystal phases of α-Al2O3 and β-Al2O3 (their ratio is 1:1 basically and α phase is a little higher); β corundum block with the main crystal phase of β-Al2O3.
Fused cast corundum products are made by melting alumina in an arc furnace and casting into designed moulds, then annealing and insulating, and finally processing with diamond abrasive tools.
With a continuous growth of technology, a good number of Chinese enterprises already have abilities of mass production on fused cast corundum products. Although naming methods between domestic manufacturers and foreign enterprises are apparently different, however, they can always be successfully matched.
Fused cast corundum series is mainly composed of alumina. As with no zirconium contained, there is nearly zero pollution to the glass. Therefore, this series is widely used in melting area and the succeeding parts of glass furnace such as chute, lip block, and damper block, and is also usually used in crown parts of an oxygen-fuel glass furnace.
As with a good crystal density, α,β corundum products have distinctive corrosion resistance to glass liquid under 1350 ºC. Fused cast α corundum products have compact structure, excellent chemical stability and much stronger erosion resistance to all kinds of slags than other aluminum silicate products. Fused cast β corundum products own good ability of thermal shock and resistance to alkali steam, and is usually used in the back part of an oxygen-fuel crown (colder areas).
Physical and Chemical Indicators