Effects of niobium on thermal stability and corrosion behavior of glassy Cu–Zr–Al–Nb alloys

The corrosion behavior of Cu95−xZrxAl5 (x=40, 42.5 and 45 at.%) in 1 N HCl, 3 mass% NaCl and 1 N H2SO4 solutions was studied. As Zr content increases, the corrosion resistance is slightly enhanced. In order to improve the corrosion resistance of the Cu–Zr–Al glassy alloy, Nb was selected to substitute Cu. Although the supercooled liquid region ΔTx of the Cu–Zr–Al glassy alloys decreases with increasing Nb content, the alloys still retain high glass-forming ability and bulk glassy samples with 1.5 mm diameter can be obtained when up to 5 at.% Nb was added. It is found that the addition of Nb results in improvement of the corrosion resistance of the glassy Cu–Zr–Al alloys.