Preparation and characterization of beta-SiAlON/TiN nanocomposites sintered by spark plasma sintering and pressureless sintering

摘要

In this research, beta-SiAlON/TiN nanocomposites were synthesized from Si3N4, Al2O3, AlN and TiO2 powders by the combination of mechanical alloying and the subsequent pressureless and spark plasma sintering. The effects of submicron and nanometer size TiO2 precursors on the microstructure, phase composition and mechanical properties of the SiAlON composites were investigated. Majority of Si3N4 particles were transformed into nanometer size which were embedded in the amorphous phase. Spark plasma sintering of the beta-SiAlON/TiN powder at temperatures as low as 1750 degrees C resulted in full density ceramics. In addition, it was observed that sintered bodies by pressureless sintering, had lower mechanical properties than the spark plasma sintered samples. Moreover, spark plasma sintered samples demonstrated optimal friction coefficient of 0.6. (C) 2016 Elsevier Ltd. All rights reserved.