Corrosion behavior of sputter-deposited W–Nb alloys in NaCl and NaOH solutions

The corrosion behavior of the sputter-deposited amorphous or nanocrystalline W–Nb alloys is studied in 10% NaCl, 0.1 and 1 M NaOH solutions at 24 °C, open to air using immersion tests and electrochemical measurements. Niobium metal acts synergistically with tungsten in enhancing the corrosion resistance of the W–Nb alloys so as to show lower corrosion rates than the corrosion rates of the alloy-constituting elements in almost all examined solutions. Corrosion rates of W–Nb alloys are about more than one order of magnitude less than that of the sputter-deposited tungsten and even lower than that of sputter-deposited niobium. The stability of the anodic passive films formed on the W–Nb alloys increase with niobium content.