Corrosion behaviors of bulk amorphous alloy Cu-Zr-Ti-Sn and its crystallized form in 3.5%NaCl solution

Corrosion behaviors of bulk amorphous alloy Cu₆₀Zr₃₀T₁₀ and (Cu₆₀Zr₃₀ T₁₀)₉₉Sn₁ and their crystallized forms in 3.5%NaCl solution were studied by potentiodynamic polarization experiments and electrochemical impedance spectroscopy (EIS). The results of potentiodynamic polarization experiment show that the anodic reaction of the amorphous (Cu₆₀Zr₃₀ T₁₀)₉₉Sn₁ has a tendency to passivation, and has lower anodic current density. Moreover, EIS experimental result shows that the amorphous (Cu₆₀Zr₃₀ T₁₀)₉₉Sn₁ alloy has higher charge transfer reaction resistance (R_t) than that of the amorphous Cu₆₀Zr₃₀T₁₀. Compared with the amorphous alloys, the crystallized alloys have larger tendency to passivation. EIS results of crystallized alloys show two impedance elements, i.e. high frequency and low frequency capacitive loops. The charge transfer reaction resistances of crystallized alloys are larger than those of amorphous alloys.