The main role of silica-Based cement free binders on the microstructural evolution and mechanical behaviour of high alumina castables

This work deals with the study of alumina castables fabricated using both silica gel technologies with the aim of establishing the main factors that determine the high temperature (1300-1400 °C, 30-300 min) microstructure and how it affects the mechanical behaviour. Deformation and fracture are determined by the formation of mullite in the matrix. Reaction kinetics is highly dependent of temperature, time and the alumina - silica relative amount at local level, determined by the composition of the binder.