Corundum brick can be classified into the following categories:
1. Sintered corundum brick
(1) Corundum brick made of sintered corundum clinker, commonly known as sintered refractory brick.
(2) With light corundum powder particles and fine powder made of corundum products, also known as sintered alumina products.
2. Fused corundum brick
(1) Cast aluminum oxide products: the alumina raw material mixture at higher than the melting temperature after melting, pouring in the prefabricated refractory model, after cooling and solidification is the crystal growth and development of the formation of products, known as cast refractory corundum . The melting method is generally used to melt.
Alumina raw material mixture melting at higher than the melting temperature, the casting in the pre-cast fire model, after cooling and solidification of the crystal growth and development of the formation of products, known as cast refractory corundum. Generally fused by an electrofusion method.
(2) Combined with fused corundum products: combined with corundum products to fused corundum clinker for the pellets, fused corundum fine powder or sintered corundum fine powder as the substrate, combined with the sintered products made of re-combination. Its production process points: fused corundum raw material processing. With fused corundum or white fused alumina as raw materials, the need to smash the frit after the election to remove the corundum block entrained silicon iron alloy or other impurities. White corundum block should be removed in addition to the crystalline form of sodium aluminate, and other low-melting, the impurity minerals due to the density of small, usually floating in the corundum frit surface, easier to identify. Corundum contains a small amount of harmful ingredients, sintering products will cause poor or cracking, it should be used in the pre-calcination. The ferrosilicon alloy is oxidized to Fe2O3 and SiO2 at 500-1000 deg, and oxidized to TiO2 (rutile), etc., all of which have a large volume expansion. After pre-calcination, these decomposition and oxidation reactions In the pre-burning process, to avoid burning in the products because of the reaction of these impurity minerals caused by expansion of product cracking.