In vitro corrosion behavior of Ti-O film deposited on fluoride-treated Mg-Zn-Y-Nd alloy

► Mg alloy substrate under composite coating has an largely improved corrosion resistance, potential to meet the requirement of long-term mechanical of Mg alloy. ► Since substrate is well protected by composite coating, Ti-O film can keep the surface integrity, hence to function as a coating with good biocompatibility. ► Pitting corrosion was found on the composite coating, resulting in more milder and slower corrosion with time. This may be beneficial to stent degradation.