Improved Corrosion Resistance of Magnesium Alloy AZ31 in Ringer Lactate by Bilayer Anodic Film/Beeswax–Colophony

A bilayer anodic film/beeswax–colophony is proposed for improving the corrosion resistance of magnesium alloy surface. The was synthesized on AZ31 by anodization and subsequent dip coating, behavior investigated electrochemical measurements weight loss test in Ringer lactate at 37 °C. improved four orders magnitude, as demonstrated ~104 times lower current density polarization curves higher film impedance spectra. tremendous surface area porous led to a strong attachment topcoat beeswax–colophony. Most coating remained attached after 14 days soaking lactate. few small blisters developed under contributed low mass 0.07 mg/cm2/day compared bare substrate, with an average rate 0.25 mg/cm2/day. Local detachment layer exposed underlying that triggered deposition Ca further nucleation Ca–P compound existence Ca?P Ca/P ratio 1.68 indicated ability promote formation bone mineral apatite.