Passivity of aluminum (Al) alloy 3003 in air and in aqueous solutions without and with chloride ions was characterized by electrochemical measurements, including cyclic polarization, electrochemical impedance spectroscopy (EIS), localized EIS and potential of zero charge, Mott–Schottky analysis and secondary ion mass spectroscopy (SIMS) technique. The related mechanism has been discussed based upon the phase constitution, formation of oxide film and oxygen content. However, the as-annealed Gd-Al-La alloys have a better corrosion resistance than the as-spun alloys. Potentiodynamic polarization measurements demonstrate that the corrosion resistance of the as-spun Gd-Al-based alloys is not sensitive to the La addition in 3.5 wt.% NaCl solution. Moreover, the La addition can affect the initial crystallization products of the Gd-Al-based alloys and induce the precipitation of Gd2O3 phase from the amorphous matrix. The inter-atomic distance increases with increasing La addition in the Gd-Al-based alloys. The results show that the La addition can obviously enhance the glass forming ability and change the crystallization mode of the Gd-Al-based alloys. The effect of La addition on glass formation, crystallization and corrosion behavior of melt-spun Gd57.1 - xAl42.9Lax (x = 0,4,8 and 12 at.%) alloys has been investigated using X-ray diffraction (XRD), differential scanning calorimetry (DSC), electrochemical measurements and field emission scanning electron microscopy (FESEM).

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