The effects of shock activation on sintering Si3N4 ceramics

Si3N4 powder was activated under several shock-wave pressures by using an explosion driven flyer impact technique. The powders had been sintered to ceramics under hot-pressing conditions during the subsequent processing. Features of the ceramics sintered from the both activated powders and original powders had been observed by SEM, TEM and XRD. Comparison of structures and mechanical properties of the ceramics showed that, the best comprehensive mechanical properties had been obtained for ceramics sintered at 1800 °C from around 40 GPa shock-wave activated powders. Bending strength and shock toughness of the ceramics were about 40–50% higher than that in the normal case. It means that the shock activation can enhance the ceramics properties with convenience and lower cost.