Abstract
The effects of heat treatment in air on the bending strength and fracture toughness of sintered silicon nitride containing CeO2, MgO and SrO additives were studied. The bending strength at elevated temperatures was improved 15 to 20% by the heat treatment (1000°C/2h), but the bending strength at room temperature was not affected. The apparent values of fracture toughness for notched specimens increased by the oxidation at the notch root.
