Fused chrome corundum

Fused fused corundum is the product of cooling and curing the raw materials such as alumina or bauxite after melting in an electric furnace. Different reducing agents can be added in the melting process due to the different varieties of fused corundum. The alumina melt near the melting point of corundum (2100℃) is similar in structure to the corundum, and crystallizes when the melt is cooled as corundum. When fused corundum melted, the molar volume increased by 23.5% and the melting heat was 109.2kj /mol. With the increase of melt temperature, its density decreased, as shown in the following equation, according to which the density of melt could be calculated.D = (3.00 ~ 1.15) x 10 ⁻ after (T - 2325) in the type d - melt density, g. cm ⁻ after; T-- melt temperature, K.

There are many types of fused corundum, such as white fused corundum, dense fused corundum, sub-white fused corundum, and brown fused corundum, etc. It is composed of sheet or rod shaped single crystals of about 1000 m.

 

Chromium corundum is mainly made of industrial aluminum oxide powder and an appropriate amount of metal oxide. Its color is light rose red, its hardness is similar to that of white corundum, and its toughness is higher than that of white corundum. Fused white corundum (Al2O3≥98%), sintered aluminum oxide powder (Al2O3≥98%) and industrial chromium oxide powder (Cr2O3≥99%) were used as raw materials. With zirconium quartz powder as the addition, according to certain particle composition grade, with sulfurous acid pulp waste liquid as the binder, under 150MPa pressure pressed forming. The sample billet was dried for 4h at 110℃ and then fired at 1750~1800℃. The fused refractory with a content of Cr2O3 in the range of 10%~15% and a combination of solid solution (Al, Cr) 2O3 has higher strength at room temperature and high temperature.

 

Fused chrome corundum refractories are fused cast refractory products consisting of a solid solution of alumina and chromium oxide and a small amount of spinel, with a volume density of 3.2-3.9g /cm. , high temperature strength, compared with other types of fused cast corundum bricks, glass melt corrosion resistance is the strongest. High bauxite (or industrial alumina) is used as the main chromite and reducing agent, which is melted at high temperature in an electric furnace and cooled slowly in a molten chromium injection model. It can be used for lining of bath kiln which is in contact with glass liquid material.