Nano Graphene Oxide Embedded Hydroxyapatite Coating on AZ91D Mg Alloy at Various Voltage for Bone Implant Application

Magnesium (Mg) and its alloys have been widely explored for biomedical applications as future biodegradable implant materials. Furthermore, a facile plasma electrolytic oxidation (PEO) technique was used to create biodegradable hydroxyapatite (HA) and nanographene oxide (nGO) coating on AZ91D Mg alloy. However, Mg and its alloy are vulnerable to the physiological environment, resulting in an untimely loss of mechanical power. Other than that, the coating factor for clinical application, such as HA, has barriers in hardness, strength, and wear resistance. This paper focuses on the physical properties and surface morphology of HA/nGO coating on AZ91D Mg alloy through PEO coating to solve the problem. The AZ91D Mg alloy was coated with HA/nGO using the PEO method at constant HA/nGO concentration and coating time, with variable voltages (115V, 230V, 345V, and 460V). Surface morphology analysis, elemental composition analysis and surface roughness, and were evaluated. Finally, the effect of a particular voltage level on the surface roughness at the constant coating time of 10 minutes indicates the surface roughness values of 1.6667 μm at 345V were obtained and demonstrate that HA/nGO samples are well disseminated at 345V coating compared to the other voltages.