Some features of the production of thermal-shock-resistant cast corundum materials in ethyl silicate binders

Abstract

Heat-resistant corundum materials are widely used in many fields of engineering because of the availability of the raw material and their excellent chemical resistance and good mechanical and dielectric properties [1].Corundum materials are the strongest in the A1203--SIO 2 system. However, because of their inadequate thermal-shock resistance they can only be used in assemblies which are not subjected to high thermal loading. The thermal-shock resistance of the normal corundum articles is equal to that of high-chamotte refractories [2]. The thermal-shock resistance of dense corundum materials is not very high. Corundum with coarse crystallization is 3-4 times more thermal-shock resistant than the corundum with a fine crystal structure [3]. High-alumina materials are used to improve the thermal-shock resistance [4]. The use of an ethyl silicate binder could be a promising method of improving the thermal-shock resistance of corundum products [5].