Corrosion assessment of Ni60 Nb30Ta10 metallic glass and its partially crystallized alloy in concentrated nitric acid environment

The corrosion resistance and passive film properties of Ni60Nb30Ta10 metallic glass and partially crystallized ribbon were investigated in 11.5 M nitric acid. The XRD study confirms the formation of nano-crystalline α-Ni in the amorphous matrix during crystallization at 650 °C under vacuum for 1 h. The electrochemical impedance spectroscopy, potentiodynamic polarization, and Mott-Schottky studies on the metallic glass exhibited higher corrosion resistance compared to the partially crystallized ribbon. XPS confirms the enrichment of Nb2O5 and Ta2O5 in the passive film of the glassy structure, while α-Ni is depleted in a partially crystallized alloy that affected the corrosion resistance.