Mechanical characterisation and hydrothermal degradation of Al2O3-15 vol% ZrO2 nanocomposites consolidated by two-step sintering

The objective of this work was to study two-step sintering as a means of controlling the microstructure of Al2O3 matrix nanocomposites containing nanometric inclusions of ZrO2 15% by volume and evaluate its hydrothermal degradation as function of time and its mechanical properties. Powders of Al2O3 and ZrO2 were prepared and compacted by means of isostatic pressing and sintering in different heating cycles. The results showed that two-step sintering allowed a more efficient microstructural control than single-step sintering, resulting in good mechanical properties. The studied nanocomposites showed excellent resistance to hydrothermal degradation compared to commercial ZrO2 and ZrO2 TZ-3Y-E.