Effects of Ga on the Corrosion Morphology of Al-Zn-Sn-Ga Anode Alloy
The corrosion behaviors of Al-Zn-Sn and Al-Zn-Sn-Ga alloys were investigated according to the results of immersion tests and corrosion morphology observation，and the Fermi energy of the precipitates was calculated by Materials Studio software for discussing the corrosion kinetics of precipitates . The results show that the Al-Zn phase with high Fermi energy (low corrosion potential) dissolved firstly, than caused the forming of Al-Ga amalgam which deposited between passive film and Al matrix. Meanwhile, the Al-Ga phase with higher Fermi energy dissolved too, which made the Al-Zn-Sn-Ga alloy continue to active, Finally, the Al-Zn-Sn-Ga alloy formed uniform corrosion morphology due to the effect of Al-Ga amalgam, while Al-Zn-Sn alloy formed the surface feature with the deep corrosion pits due to the "self-catalysis" mechanism.
Huixuan Zhang, Ye Han, Fuxiao Chen and Jiuba Wen
J. B. Wen et al., "Effects of Ga on the Corrosion Morphology of Al-Zn-Sn-Ga Anode Alloy", Applied Mechanics and Materials, Vols. 117-119, pp. 1048-1051, 2012