High alumina firebricks are classified according to the alumina content which is from lowest  48% to highest 95%, manufactured from mineral of bauxite, corundum, etc. by mixing, press-forming, drying, sintering and machining. High alumina bricks feature stable mechanical strength and thermal shock resistance, with high refractoriness of no lower than 1880℃, High alumina bricks are commonly used as refractory lining exposed to heat directly or backup insulation linings in various types of industrial kiln or laboratory furnace.

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