High‐Temperature Firing of Basic Refractories

Abstract

An investigation was conducted to determine the hot modulus of rupture strength, the tendency to burst under iron oxide attack, the tendency to creep, and the hot-load-bearing strength of chromite-bearing basic refractories fired from 1400" to 2000°C. Petrographic examination was employed to define the mechanisms of improved bonding which resulted from firing at high temperatures. The results of these physical and chemical tests and the observed microstructure indicated that a greatly improved, highly stabilized basic refractory could be obtained by proper brick design and firing to temperatures of approximately 1700°C. Control of design features such as total silica content, chromite/periclase ratio, and chromite sizing was found to be necessary to achieve superior properties through high-temperature firing.