The effect of addition of K2ZrF6 on the structures and properties of AZ31 magnesium alloy MAO coating.

It is a challenge to improve the corrosion rate and blood compatibility of biomedical magnesium alloy implants in human body. Scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and X-ray diffraction (XRD) were used to study the Properties of K 2 ZrF 6 modified AZ31 magnesium alloy composite coating. The corrosion behavior of the sample in simulated body fluid (SBF) was evaluated by hydrogen evolution corrosion, potentiodynamic polarization cur ve and electrochemical impedance spectroscopy. The results show that the corrosion resistance of magnesium alloy is significantly improved by composite coating. The wettability test shows that K 2 ZrF 6 greatly improves the biocompatibility of MAO coating on magnesium alloy. The hemolysis test shows that the composite coating makes magnesium alloy have low hemolysis rate. The increase of PH value and magnesium ion concentration in solution caused by corrosion of magnesium alloy can be adjusted by adding K 2 ZrF 6. The corrosion resistance mechanism of MAO coating on K 2 ZrF 6 modified magnesium alloy was discussed. In this experiment, the optimum amount of K 2 ZrF 6 is 4 g/L. • MgO/K 2 ZrF 6 composite coating on the surface of magnesium alloy was successfully prepared. • K 2 ZrF 6 helps to improve the corrosion resistance of magnesium alloy microarc oxide coatings. • Magnesium alloy can be widely used in medical field by MgO/K 2 ZrF 6 composite coating. [ABSTRACT FROM AUTHOR]