Effect of Y addition on the corrosion behavior of melt-spun amorphous Mg-Cu ribbons

Hydrogen evolution testing and anodic potentiodynamic polarization revealed that Y addition has a beneficial effect on the corrosion resistance of melt-spun amorphous Mg-Cu ribbon, which is related to the properties of the surface film of Mg-Cu and the manner in which its properties are modified as a result of Y alloying. X-ray photoelectron spectroscopy (XPS) depth profiling revealed that the breakdown of Mg-Cu was caused by the hydration of surface oxide components and the incorporation of detrimental CO₃^2- anions into the surface film. Y addition in Mg-Cu improves the corrosion resistance by Y₂O₃ incorporation into the passive film, thus stabilizing the surface oxide components from hydration and preventing the incorporation of CO₃^2- into the passive film.