Introduction of corundum mullite bricks
Production technology of corundum mullite brick
Corundum mullite brick body was formed by a 300t friction press with a density of 2.7g/cm3. The billets are dried in a tunnel dryer. The inlet temperature is 40~50℃, the maximum drying temperature is 130℃, the drying time is 48h, and the water content of the body is not more than 1.5%. The product is fired in the tunnel kiln, the firing temperature is 1550℃, and the holding time is 10h.
Forming method of corundum mullite brick
(1) Refractory products with complex shape and large size are rammed with an air hammer or formed by vibration.
(2) Ordinary products or standard specifications can be semi-dry high-pressure molding.
(3) Special-shaped pure or special products need to design molds and use isostatic pressing.
Physical properties of corundum mullite bricks
The high temperature main crystalline phases of corundum mullite brick are corundum and mullite. The crystals of corundum are short columns and barrels, which are not interspersed and interlaced in the resistant material structure. The corundum crystals are interlaced with mullite columnar crystals, which can effectively prevent the sliding of corundum crystals and obtain a stable structure. Because the crystal structure is more stable, it is more conducive to the excellent performance of mullite or mullite and corundum, such as melting point: mullite 1870℃, corundum 2050℃, and the high fusion temperature of the two is 1840℃, which is conducive to the improvement and improvement of the high temperature performance of the material.
Advantages and characteristics of corundum mullite brick
(1) High temperature resistance, high fire resistance temperature and high load softening temperature.
(2) Chemical erosion resistance, strong resistance to acidic solution or slag.
(3) Antioxidant. It is not easy for O2, H2, CO and other gases to react chemically.
(4) Good thermal stability, high temperature volume stability, not easy to expand or shrink.
(5) Good thermal shock resistance, cold and heat resistance is not easy to flake.
(6) High compressive strength at room temperature, not easy to wear when handling or unloading.
