The effect of an MgO intermediate layer on a nanostructured HA coating fabricated by HVOF on an Mg alloy

Abstract

Lightweight magnesium alloys are currently being investigated as implants due to their biodegradability and mechanical properties. However, their clinical applications are limited by their high corrosion rate in the physiological environment. Coating Mg-based alloys is an approach that is used to delay primary corrosion and increase their lifetime. Therefore, hydroxyapatite was coated on anodized and non-anodized magnesium substrates using high-velocity oxy-fuel spraying. This study aimed to evaluate the effect of the MgO intermediate layer between the hydroxyapatite coating and Mg alloy substrate. The microstructure and corrosion behaviour of the coated samples are the main focuses of this study. X-ray diffraction spectroscopy was used to analyse the phases. Electrochemical impedance spectroscopy was performed in simulated body fluid. The results revealed that the presence of an anodized layer increased corrosion resistance.