Improvement of Corrosion Resistance of Rare-Earth Element (REE) – Based Anodic Coating on Biodegradable Magnesium Alloy

AZ91D alloy has been widely used in fields of materials science, tissue engineering, biomedicine, and analytical science due to its simple preparation, low-cost, and high biocompatibility. To overcome their weaknesses which low corrosion resistance due to high surface reactivity. The effectiveness of the lanthanum (La) on corrosion resistance, has exhibited great potentials for improving its protective properties. AZ91D alloy has been coated with lanthanum nitrate and magnesium nitrate through anodizing at fixed concentration and treatment time, with various current density. Surface roughness, elemental compositional analysis, surface morphology analysis, and corrosion behavior were analyzed for the corrosion response at various current density. JIS H 0541 Standard was used to determine the corrosion rate of the samples. It is showed that the sample undergoing 10 mA/\({\mathrm{cm}}^{2}\) current density indicated the highest corrosion resistance due to their value on corrosion rate 8.6 mm/year was the lowest value and their surface roughness 0.199 µm was in the range of recommended roughness for a biomedical implant.