Corundum mullite brick performance: has good high temperature strength, high temperature creep resistance, thermal shock resistance and corrosion resistance. The physical and chemical properties of a typical corundum-mullite brick are: Al2O3> 85%, Fe2O3 0.45%, apparent porosity 19%, normal temperature compressive strength greater than 55MPa load softening temperature greater than 1700 ℃, heating line changes (1600 ℃, 3h)-0.1%, thermal shock resistance (1100℃ water cooling) is more than 30 times.

Corundum mullite brick features:

(1) High temperature resistance, high refractory temperature and high load softening temperature.

(2) It is resistant to chemical erosion and has strong resistance to acidic solutions or slag.

(3) Antioxidant. It is not easy to chemically react with gases such as O2, H2, and CO.

(4) Good thermal stability, stable volume at high temperature, not easy to expand or shrink.

(5) Good thermal shock resistance, resistance to rapid cooling and rapid heating is not easy

 peel off.

(6) It has high compressive strength at room temperature and is not easy to wear during handling or unloading.

Corundum mullite brick process: pure mullite raw materials synthesized from industrial alumina powder and pure clay, bauxite or silica, especially the alkali metal oxide content should be as low as possible. Products made with mullite aggregates as aggregate have good thermal shock resistance, but slightly poor corrosion resistance. Products with corundum sand as aggregate have good corrosion resistance, but slightly poor thermal shock resistance.

The forming method of corundum mullite brick:

(1) Refractory products with complex shapes and large sizes are rammed or vibrated with air hammers.

(2) Ordinary products or standard sizes can be formed by semi-dry high pressure molding.

(3) Special-shaped pure or special products need to design molds and use isostatic pressing.

Corundum mullite is usually made of synthetic mullite to make corundum-mullite bricks. Mullite particles can be used as 

aggregates, α-Al2O3 powders can be used as powders, and fused or sintered corundum particles can also be used as aggregates, Synthetic mullite powder is powder. Aggregate and powder are batched according to a certain proportion and particle size gradation. The waste liquid of sulfite pulp is used as a binder, and the materials are added in a certain order, fully mixed and evenly mixed, and formed by a friction brick press or a hydraulic brick press. After the bricks are dried, they are fired at 1650-1750°C.

Some use fused or sintered corundum sand as the aggregate, with a composition ratio of mullite or corundum-mullite. Bauxite or clay with high α-Al2O3 is mixed with fine powder as powder for batching to make bricks.

Corundum mullite application range: mainly used in high air temperature hot blast stove, also used in glass melting furnace and as ceramic firing kiln furniture.