Galvanic corrosion of a copper alloy in lithium bromide heavy brine environments

Galvanic corrosion of the copper alloy 84% Cu-15% Zn-1% Nl was studied in 55wt% lithium bromide (LIBr) environments. The galvanic couples studied were: 84% Cu-15% Zn-1% NiTi2, 84% Cu-15% Zn-1% NI-T17, 84% Cu-15% Zn-1% Nl-30% Cu-70% Nl, 84% Cu-15% Zn-1% Nl-Pb, 84% Cu-15% Zn-1% NlAg, and 84% Cu-15% Zn-1% Ni-Sn. Potentlodynamlc polarization measurements, open-circuit potential (OCP), and weight change measurements were carried out to evaluate the galvanic effect. Results Indicated that Ti alloys and 30% Cu-70% Nt were the most passive alloys tested, and they behaved as cathodes. Although galvanic corrosion was expected, a negligible effect was measured because of an effective passivation layer on the surface of Ti alloys and 30% Cu-70% Nl. Pb, Ag, and Sn showed anodic behavior as compared to 84% Cu-15% Zn-1 % NL As a result oj the galvanic coupling, significant weight loss of these metals was measured. Sn was the most effective anode as compared to the other tested alloys; It acted as a sacrificial anode. Sn provided effective cathodtc protection to 84% Cu-15% Zn-1% Nl In 55wt% LIBr environments at 140°C.