Mechanism and kinetics of anodic dissolution of aluminum and its alloys with zinc and rare-earths in a sodium polyvanadate solution

Gravimetry, ac impedance, X-ray photoelectron spectroscopy, and anodic polarization curves are used to demonstrate that the Al-Zn(45 wt%) alloy has a lower corrosion resistance in a 0.5 M NaVO3 solution at 298 K than the same alloy microdoped with rare earths (0.1 wt%). The minimum electrode capacitance at the metal-solution interface is displayed by the Al-Zn (45 wt%) alloy, and the maximum, by the Al-Zn (45 wt%)-Sc (0.1 wt%) alloy; the latter is also characterized by a minimum current density of anodic passivation.