Untypical Young's modulus evolution of model refractories at high temperature

Industrial refractories can exhibit untypical Young's modulus behaviour versus temperature, characterized by hysteretic loops in the plot E(T). This paper shows how the use of simplified model materials helps in the understanding of such behaviours, obviously depending both on the properties of each component of the refractory material and on the presence of internal defects. Model materials constituted of a hot-pressed glass matrix surrounding spherical alumina inclusions have been studied. Glasses exhibiting various coefficients of thermal expansion (CTE) have been used as matrix in order to obtain three typical microstructural configurations (Δα < 0, Δα = 0 and Δα > 0, where Δα denotes the CTE difference between matrix and inclusions).