Corrosion behaviour of amorphous Ti48Cu52, Ti50Cu50 and Ti60Ni40 alloys investigated by potentiodynamic polarization method

Abstract

Potentiodynamic polarization studies were carried out on virgin specimens of amorphous alloys Ti48Cu52, Ti50Cu50 and Ti60Ni40 in 0.5 M HNO3, 0.5 M H2SO4 and 0·5 M NaOH aqueous media at room temperature. The value of the corrosion current density (Icorr) was maximum for Ti48Cu52 alloy in all the three aqueous media as compared to the remaining two alloys. The value of Icorr for the alloy Ti48Cu52 was maximum (Icorr = 2.6 × 10-5 A/cm2) in 0.5 M H2SO4 and minimum (Icorr = 3.5 × 10-6 A/cm2) in 0.5 M NaOH aqueous solutions. In contrast, the alloy Ti60Ni40 exhibited the least corrosion current density in 0.5 M HNO3 (Icorr = 4.0 × 10-7 A/cm2) and in 0.5 M NaOH (Icorr = 5.5 × 10-7 A/cm2) aqueous media as compared to those for Ti-Cu alloys, while its value in 0·5 M H2SO4 was comparable to that for Ti50Cu50. It is suggested that the alloy Ti60Ni40 is more corrosion resistant than the alloys Ti48Cu52 and Ti50Cu50 in all the three aqueous media.