The Ceramic Composition Using Vermiculite

Abstract

The possibility of obtaining effective wall materials and technological lightweight products for high-temperature insulation by introducing the expanded vermiculite into the ceramic mass is investigated. Mineralogy of used clays and vermiculites was studied. They are represented by minerals of the same class, and therefore weak adhesion of smooth surfaces of vermiculite grains is compensated by common genetic origin with the matrix of the basic material of the composite. Thermotechnical studies of the process of swelling of vermiculite in a quartz furnace showed that to obtain a relatively high mechanical strength of vermiculite grains, it is necessary to select the maximum temperature and the mode of swelling, so that the planar shape of vermiculite plates remains and there is no pronounced warping. The degree of thermal delamination is influenced by the particle size, the increase of which entails a deterioration in physical and mechanical properties. The introduction of a high percentage of vermiculite additives in the charge allows to obtain lightweight thermal insulation products.