High-temperature mechanical behavior of Al2O3/graphite composites

Uniaxial compressive creep behaviour of spark-plasma-sintered Al2O3/graphite particulate composites has been studied at temperature between 1250 and 1350 °C. Values of stress exponent, n, ranging from 1 to 1.4 and, activation energy, Q, of 600 ± 40 kJ/mol have been determined. With 10 vol% graphite in the composite, the creep deformation of the composite is controlled by the fine-grained Al2O3 matrix, where Coble creep has been identified as the dominant creep mechanism.