Main factors affecting the thermal shock resistance of refractory products is the material in the heating or cooling process due to thermal expansion and contraction of the thermal stress. The greater the rate of thermal expansion, thermal shock resistance is poor, such as brick, magnesia brick; thermal conductivity and better thermal shock resistance is greater, such as silicon carbide products etc.
Starting from the thermal elastic theory, the elastic modulus of the material is small, the greater the intensity, large thermal conductivity, good thermal shock resistance products. The energy theory that the fracture surface products have higher energy, can improve the thermal shock resistance of products. When the product has fine pores, making products to produce a large internal stress when the temperature changes, the internal storage of more energy, can produce micro cracks by products, and will be released from these products may lead to damage to energy, can greatly improve the products of thermal shock resistance, namely in the products to introduce the micro cracks, crack propagation to be minimized, is one of the ways to improve the thermal shock resistance of materials.
Antistripping high alumina brick for cement kiln, because adding a small amount of ZrO2 in high alumina brick ingredients after ZrO2 transformation by making products formed in many micro cracks, when the temperature changes of thermal stress, the micro cracks may lead to damage of refractories energy to be released, so as to improve the high the thermal shock resistance of alumina brick.