Control the Corrosion of Magnesium for Implant Application By Hydrothermally Deposited Biodegradable Calcium Phosphate Coating
EIS results showed that the size of capacitance loops and the absolute impedance value (|Z|) increases. By increasing the deposition time the corrosion mechanism was changed as a result of partial delamination of top surface of coating. In agreement with the electrochemical experiments, immersion tests in SBF also indicated large improvement in corrosion protection as the mass loss was reduced almost three times when coating was applied as compared to the bare metal.
The uncoated Mg substrate undergoes severe and non-uniform corrosion after 28 days immersion in SBF solution; while, the coated samples displayed intact coating and no obvious pits were observed on the coating surface.
The described biocompatible and biodegradable coatings significantly improved corrosion resistance of Mg substrate and can be promising candidate for biomedical application.
Keywords: Magnesium, Calcium-Phosphate coating, Corrosion resistance, EIS