Abstract: Magnesium alloy has attracted the attention of the biomaterials community as a potential biodegradable metallic candidate for stents and orthopedic applications. The high corrosion rate of magnesium alloy confines their application in clinical. Therefore， it′s one of the main approaches to develop Mg-based biomaterials with good corrosion resistance and high strength for biomedical engineering. The apatite coatings were deposited on matrix through biomimetic method. The coating was characterized by XRD and SEM. The degradation rates of the samples without and with hydroxyaptite coating were researched in the simulated body fluid(SBF). The results showed that surface modification improves the corrosion resistance. The degradation rate of the Mg-Zn-Sr alloy with coating was slower than that of the alloy without coating on the surface.

Key words: Mg-Zn-Sr alloy, biomimetic coating technique, simulated body fluid, degradation rate, corrosion