Composite coating of HA-CNTs-Gelatin on Mg alloy as a potential bone implant: Microstructure evaluation

Mg and its alloys, with their non-toxic nature, combine a moderate elastic modulus with a low density, which matches that of natural bone. The major drawback of Mg and its alloys is the fast degradation in biological environments. This degradation is accompanied by the production of hydrogen gas that can affect the pH-dependent physiological processes around the implant. To improve their biomedical performance, the present study considers composite coating of nano-hydroxyapatite/multi-walled carbon nanotubes in a Gelatin matrix on ZK۱۰ magnesium alloy (Mg–۱.۰ wt.% Zn–۰.۵ wt.% Zr) using plasma electrolytic oxidation and electrophoretic deposition for temporary orthopedic implants. Microstructure and surface morphology of the composite coatings were evaluated using a scanning electron microscope combined energy dispersive X-ray spectrometer and atomic force microscopy, respectively. The results show a continuous and crack-free morphology for HA–CNTs- Gelatin coatings on the pretreated Mg alloy included Ca, P, C, O, and Mg elements.