Magnesium-chromium bricks are refractories with magnesium oxide (MgO) and chromium trioxide (Cr2O3) as the main components, and periclase and spinel as the main mineral components. The regenerative brick has high fireproof, high temperature strength, strong corrosion resistance to alkaline slag, excellent thermal stability and certain adaptability to acid slag. The main materials for making magnesia-chromium bricks are sintered magnesia and chromite. The purity of magnesia should be as high as possible. The chemical composition of chromite should be Cr2O3:30-45% and CaO:<1.0-1.5%.
Magnesium chromium bricks are mainly used in metallurgical industry, such as open-hearth furnace roof, electric furnace roof, out-of-furnace refining furnace and various non-ferrous metal smelting furnaces. Magnesium-chromium bricks are melted in the high temperature part of the wall of UHP electric furnace, magnesia-chromium bricks made of synthetic materials are used in the high erosion area of the refining furnace outside the furnace, and magnesia-chromium bricks made of melted magnesia-chromium bricks and synthetic materials are used in the high erosion area of non-ferrous metal flash smelting furnace. In addition, magnesia-chrome bricks are also used in the burning zone of cement rotary kiln and regenerator of glass kiln.