Characterization of spark plasma sintered graphene reinforced zirconia toughened alumina (ZTA) composites

Zirconia toughened alumina (ZTA) based composites are gaining more attention due to their mechanical properties and biocompatibility. They are widely used in orthopedic and dental applications. This study reports the production and characterization of graphene nanoplatelets (GNPs) reinforced ZTA ceramics. For this, 70Al2O3-(30-x)YSZ-(x)GNP systems (in vol.%, x = 1, 3, 4, 5) were prepared. All mixtures underwent densification via spark plasma sintering (SPS) at 1400 °C with 5 min hold time under 40 MPa applied pressure. The densification, resulting microstructure, and mechanical characteristics were thoroughly examined. The incorporation of GNPs into ZTA composites was found to improve fracture toughness by ~ 20% without changing the Vickers hardness values. The preliminary biocompatibility assessment of the ZTA3G sample revealed that the composite did not exhibit any cytotoxic effects against human osteoblast cells.