The effect of zirconium (Zr) addition on the glass-forming ability (GFA) and mechanical properties of the Ni61.5Nb38.5 alloy has been studied. The addition of Zr improves the GFA. When x = 5 for Ni61.5Nb38.5−xZrx (in at.%) alloys, the alloy exhibits the best GFA and can be cast into 3-mm-diameter amorphous samples by using the copper mold injection-casting method. Differential scanning calorimetry measurements indicated that the thermal parameters, such as Trg and γ, have not a good correlation with the GFA in the Ni–Nb–Zr alloys. Compression tests reveal that the addition of Zr just decreases the fracture strength slightly from 3.4 to 3 GPa and that all of the tested samples exhibit a little compressive plasticity of about 2%. When x = 9, the feature of the fracture surface indicates that the alloy has a tendency for transition from the ductile to the brittle. And delicate “dimple” and microscale vein pattern structures have been observed on it.
Unequal effect of thermodynamics and kinetics on glass forming ability of Cu–Zr alloys
