Manufacturing of mullite corundum brick

Using synthetic mullite and fused white corundum as raw materials, and Suzhou soil as a binder, mullite corundum bricks for electric stove tops can be made.

Composition of mullite corundum brick

The synthetic mullite is crushed to <4mm as aggregate, fused white corundum is ground to <0.074mm as fine powder, and the dried Suzhou soil is vibrated and ground <0.5mm as binder. The proportion of ingredients is as follows: synthetic mullite 55-65%, fused white corundum 25-30%, and Suzhou soil 8-10%. The batch materials are mixed with a wet mill. When mixing, add pellets first, mix for 1~2min, then add binder and mix for 2~3min, finally add fine powder and mix for 3~5min, the total mixing time is about 10min.

The firing process of mullite corundum brick

The green body is formed by a 300t friction brick press, and the green body density is 2.70g/cm3. The embryo body is dried in a tunnel dryer. The inlet temperature is 40~50℃, the highest drying temperature is 130℃, the drying time is 48h, and the moisture content of the embryo body is not more than 1.5%. The product is fired in a tunnel kiln, the firing temperature is 1550℃, and the holding time is 10h.

The physical and chemical indexes of mullite corundum brick

The physical and chemical indicators of the product are as follows: Al2O373.06%, SiO224.10%, apparent porosity 19.9%, bulk density 2.55g/cm3, normal temperature compressive strength 81.7MPa, 1550℃, 3h reburning linear change rate -0.11%, load The softening start temperature is 1710°C.

Mullite corundum bricks are used as superstructure bricks, forehearth bricks, cover plates, metallurgical and other industrial medium-temperature furnace linings, carbon black reaction furnace cold sections, and other industrial thermal equipment linings.