Microstructure Formation and Performance of Reactive Sintered Titanium Oxycarbide Base Ceramic-Ceramic Composites

Abstract

Reactive sintering is a process where synthesis reaction of the ceramic phases is combined with sintering (densification) of the composite. Dense lightweight titanium oxycarbide-aluminium oxide ceramic-ceramic composites were produced from titanium dioxide, carbon black as graphite source and aluminium precursors by high energy attritor milling, followed by reactive sintering. Titanium oxycarbide and aluminium oxide phases were synthesized during reactive sintering in situ. To investigate the microstructure evolution and phase formation, the specimens were sintered at different temperatures (600-1725 °C) in vacuum. Scanning electron microscopy and X-ray diffraction were used to analyze the microstructure and phase formation. Mechanical performance (hardness and fracture toughness) was evaluated.