Development of yttria-stabilized zirconia and graphene coatings obtained by suspension plasma spraying: Thermal stability and influence on mechanical properties

This study investigated the feasibility of depositing graphene nanoplatelet (GNP)-reinforced yttria-stabilized zirconia (YSZ) composite coatings. The coatings were deposited from an ethanol-based mixed YSZ and GNP suspension using plasma spraying (SPS). Raman spectroscopy confirmed presence GNPs in matrix, scanning electron microscopy (SEM) analysis revealed a desired columnar microstructure with distributed predominantly inter-columnar spacing matrix. as-deposited YSZ-GNP subjected to different isothermal treatments—400, 500, 600 °C for 8 h—to thermal stability showed retention specimens exposed temperatures up 500 °C, although defect concentration graphitic structure increased increasing temperature. Only marginal effect on mechanical properties (i.e., hardness fracture toughness) was observed isothermally treated