Phase analysis, mechanical properties and in vitro bioactivity of graphene nanoplatelet-reinforced silicon nitride-calcium phosphate composites

The aim of this study is to produce highly dense Si3N4 based composites with good mechanical properties and bioactivity. ceramics without using sintering aids, Si3N4-HA Si3N4-HA-GNP have been produced by spark plasma (SPS) at temperatures 1525–1550°C. effect reinforcement type content on the densification behavior, phase analysis, microstructural development, properties, in-vitro bioactivity behavior were systematically investigated. Monolithic that contains a high amount ?-Si3N4 (~87 wt%) was nearly full (~99%). Hydroxyapatite (HA) used as starting powder during preparation binary triple provide Si3N4, after sintering, HA transformed into tricalcium phosphate (?-TCP ?-TCP) polymorphs. incorporation GNPs had positive stability ?-TCP phases higher temperatures. improvement in indentation fracture toughness samples GNP mainly attributable pull-out crack deflection mechanisms. In-vitro added enhanced increasing ?-TCP content. More calcium phosphate-based particle formation observed compared Si3N4-HA.