Al-magnesia-carbon bricks refer to refractory products made of special high-grade bauxite or corundum sand, magnesia and flake graphite as the main raw materials. Al-magnesia-carbon bricks are fire-lined products made from special high-grade bauxite or corundum sand, magnesia and flake graphite as main raw materials. Its characteristic is that in addition to the advantages of high corrosion resistance and resistance to peeling due to carbon content at high temperatures, it also has the advantage of showing a high residual linear expansion rate due to heat generated spinel during use, thus becoming a newly developed high-quality Lining bricks.
The characteristic of the aluminum-magnesium-carbon brick is that in addition to the advantages of high corrosion resistance and resistance to peeling due to carbon content, it also has the advantage of showing a high residual linear expansion rate due to the formation of spinel when heated during use. Newly developed high-quality lining bricks. Containing Al2O3 60%～69%, MgO 7%～14%, C 5%～12%. It has good resistance to slag erosion and thermal shock, and has a small amount of re-burning expansion.
Aluminum-magnesium-carbon bricks have the advantages of corrosion resistance, spalling resistance, balanced erosion, safe use, less staining of steel and slag, and easy unpacking. It is mainly used for the lining of Shenggang Poke under harsh conditions. The use of aluminum-magnesium-carbon bricks as linings in the molten pool and the bottom of the continuous casting large tundish and refining ladle outside the furnace is increasing.
In order to improve its oxidation resistance, additives such as Si powder, Al powder, SiC powder or ferrosilicon powder can be appropriately added to the ingredients. The resin is used as a binder, and it is molded under high pressure. It can be used after being treated at 200-300°C. Calcined. It is mainly used for ladle lining of large converters and ultra-high power electric furnaces and refining furnace linings outside the furnace.
Special high alumina bauxite is used as raw material, because it contains a certain proportion of SiO2 and other impurities, and its structure is not dense, and its resistance to slag erosion is poor. In order to improve its slag resistance, fused or sintered corundum can be used to replace part of the special high alumina bauxite earth. In order to improve the oxidation resistance and high temperature strength of the product, a small amount of metal powder is added, but the thermal shock resistance is reduced, and the content of flake graphite is increased.
