Lightweight mullite castable is a kind of refractory material with excellent high temperature performance and good thermal insulation performance. Since it is produced with high-quality synthetic raw materials and is combined in the form of low-cement or micropowder, it can be directly applied to high-temperature parts in contact with flames.
Factors that affect performance of lightweight mullite castable
Effect on castable by lightweight aggregate type and bulk density
Light weight mullite castable made of the same type of light aggregate with higher bulk density has higher compressive strength and flexural strength. The production process of different manufacturers is different, and the strength of the lightweight aggregate itself is also quite different. The choice of raw materials should be determined by testing the castable test block.
Effect on the strength of castable by the amount of cement addition
Increasing the amount of cement added will significantly improve the normal temperature strength of the castable, but because calcium aluminate cement contains more calcium oxide, the castable will produce a large number of crystal phases such as CA6 and CAS2 at high temperature, which will negatively affect the castable strength under medium temperature and high temperature, and negatively affect castable’s spalling resistance. So the amount of cement added should be 5% to 10%.
Next issue we will continue to introduce lightweight mullite castables for heating furnace. Please stay tuned!
