Features of Hardening of Aluminosilicophosphate Binder in Cellular Concrete

Abstract

Cellular phosphate concretes are used as an insulating material for some high-temperature aggregates due to their high temperature resistance, fire resistance and residual strength at the level of values after drying. The use of industrial waste in phosphate cellular concrete technology made it possible to improve some properties without reducing the application temperature. The paper shows that dispersed aluminosilicate waste from refractory production has sufficient activity (porization ability) to obtain a phosphate binder. The features of the hardening of an aluminosilicophosphate binder cured with dispersed metallic aluminum have been studied; the change in the phase composition of the cured binder after firing at different temperatures has been studied by differential thermal and X-ray phase analysis. It has been established that the developed aluminosilicophosphate binder makes it possible to obtain fireclay cellular concrete with an application temperature of up to 1400оC. A comparison of the changes in the phase composition for the developed aluminosilicophosphate composition and a pure aluminophosphate binder is performed. A shift in the temperature of the processes is noted in an upward direction for the aluminosilicophosphate binder, which is explained by the fact that silicon ions do not form independent phosphate compounds, but are embedded in the crystal lattice of aluminophosphates, changing their properties and shifting the intervals of phase transitions.