Efficacy of graphene nanosheets on the plasma sprayed hydroxyapatite coating: Improved strength, toughness and in-vitro bioperformance with osteoblast

Graphene nanosheet (GNS) reinforced HA coating on Ti6Al4V substrate, fabricated using plasma spray, was developed for biomedical applications. Microstructural observation corroborated that the adding GNSs homoge-neously distributed in the GNS/HA coating with typical lamellar structure featured by GNSs acting as binder be-tween the discrete HA splats. Meanwhile, GNSs were observed to get in direct contact with HA matrix and form a clean GNS-HA interface without interfacial product. Results of various indentation tests showed simultaneous improvement in both indentation yield strength (similar to 379 MPa) and fracture toughness (0.78 +/- 0.17 MPam1/2), mainly attributing to synergetic toughening and strengthening mechanisms associated with the adding GNSs such as load transfer, GNS pull-out, inter-layer sliding of a GNS, crack branching, GNS bridging and crack deflec-tion. In addition, the GNS/HA coating exhibited improved biocompatible with MG-63 cell in terms of its attach-ment, adhesion strength, proliferation and differentiation. Hence, the GNS/HA composite coating with improved strength, toughness and enhanced biocompatibility makes it a promising candidate for bone regeneration and implantation. (C) 2021 The Authors. Published by Elsevier Ltd.

Automated summary

A graphene nanosheet (GNS) reinforced HA coating was developed using plasma spray for biomedical applications. The coating showed improved strength, toughness, and enhanced biocompatibility, making it a promising candidate for bone regeneration and implantation.