Investigation of Incorporation of Hydroxyapatite Nanoparticles and Process Electrical Parameters on Corrosion Behavior of Ceramic Coatings Developed on AZ31 Magnesium Alloy by MAO Technique

mproving corrosion resistance is one of the main goals of orthopedic implants. In this regard, this study aims to improve the quality and efficiency of the AZ31 M agnesium alloy by phosphate coatings containing hydroxyapatite and ZnO nanoparticles by M AO method. For this purpose, first, the effect of adding hydroxyapatite nanoparticles in constant current mode was investigated and then the effective parameters in this method, including time and duty cycle, were studied. Corrosion behavior of the coatings was investigated in Ringer's solution by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). M icrostructural and phase studies of coatings by field emission scanning electron microscopy (FESEM /EDS) and X-ray diffraction (XRD) analysis before and after corrosion test showed better performance of the coating produced in the electrolyte containing 3 grams per liter of hydroxyapatite nanoparticles in 7 minutes and 50% duty cycle.