Corundum Mullite Castable

Corundum-mullite castable is a refractory castable made with dense corundum and mullite as aggregates, and white corundum powder, α-Al2O3 micropowder, and mullite powder as fine powders. It is an unshaped refractory material with excellent resistance to alkaline corrosion among refractory materials, and can be used for casting in rotary kiln mouths and complex-shaped furnace linings.

一.Physical And Chemical Indicators of Corundum Mullite Castable

二.Corundum-mullite castable refractory features: It possesses the combined advantages of corundum and mullite castables; it has high high-temperature strength, good thermal shock resistance and resistance to structural spalling; it exhibits good thermal shock resistance, high load softening temperature, low high-temperature creep rate, and good chemical corrosion resistance. It can be used for wear-resistant linings in large power plant boilers and other high-temperature furnaces.

三.To enhance the strength and performance of aluminum-silicate castables, the following common technical measures should be adopted (referring to cement-based castables):

(1) Matrix composition. The matrix composition has a significant impact on the service temperature, high-temperature mechanical properties, and sintering performance of the castable. The matrix should mainly consist of bauxite clinker with low K2O and Na2O content, controlling the amount of cement added and optimizing the mix design to make the castable matrix approximate the chemical composition of mullite (A3S2).

(2) Binder. Pure calcium aluminate cement should be selected as the binder.

(3) Addition of an appropriate amount of fine powder.

(4) High-temperature strengthening agent.