Fretting wear mechanism of plasma-sprayed CNT-reinforced wollastonite-zirconia composite coatings for bioimplant applications

Dataset for journal article with title: Fretting wear mechanism of plasma-sprayed CNT-reinforced wollastonite-zirconia composite coatings for bioimplant applications. This study investigates the fretting wear mechanisms of plasma-sprayed wollastonite-zirconia (CaSiO3-ZrO2, WaZr) composite coatings, both unreinforced and reinforced with carbon nanotubes (WaZr-CNT), for bioimplant applications. The developed coatings are compared with conventional hydroxyapatite (HA) coatings on titanium substrates. Microstructural analysis reveals that CNT reinforcement leads to a denser, more uniformly bonded WaZr-CNT coating through effective splat bridging and pore sealing. Mechanical characterization shows that WaZr-CNT coatings possess higher microhardness and lower elastic modulus than unreinforced WaZr coating. During fretting tests at a 200 µm displacement amplitude, the WaZr-CNT coating exhibited an approximately 83 % reduction in energy dissipation compared to HA coatings and a 75 % reduction compared to WaZr coatings, indicating significant improvement in fretting resistance. While HA and WaZr coatings underwent splat fracture and generated considerable amount of wear debris, the WaZr-CNT coating produced almost no debris and maintained intact splat boundaries. The novelty of this work lies in the development and evaluation of CNT-reinforced WaZr coatings that for the first time undergo fretting tests and demonstrate superior fretting wear resistance under cyclic sliding contact compared to unreinforced WaZr and conventional HA coatings.