An abnormal correlation between electron work function and corrosion resistance in Ti-Zr-Be-(Ni/Fe) metallic glasses

In this work, we correlate corrosion behaviour of metallic glasses (MGs) to electron characteristic based on magnitude and local distribution of electron work function (EWF). An abnormal phenomenon has been addressed that a low EWF leads to superior corrosion resistance in 3.5 wt.% NaCl solution for Ti-Zr-Be-(Ni-Fe) MGs. Because a low EWF, corresponding to high electron activity, facilitates interfacial passivation reactions to form highly protective passive film, which is accompanied by the enrichment of TiO2 and ZrO2. Besides, heterogeneous EWF-distribution that is related to electrochemical heterogeneity, indicates the formation of preferential sites for pitting nucleation, therefore deteriorating corrosion resistance.