Electrochemical characteristics of Pb-Sb alloys in sulfuric acid solutions

Lead-antimony alloys with a wide range of Sb contents, pure Pb and pure Sb were subjected to sulfuric acid solutions to elucidate their electrochemica l characteristics by cyclic voltammetry and corrosion potential measurement s. A corrosion test with a Pb/Sb galvanic couple was also done. For Pb-rich alpha-phase alloys (< 0.3 wt.% Sb), their electrochemical behavior was sim ilar to that of pure Pb. On the other hand, for alpha + beta phase alloys ( > 0.3 wt.% Sb) their behavior was quite different from those of alpha-phase alloys; (i) dissolution current of Sb was proportional to Sb contents; (ii ) hydrogen overvoltage was decreased remarkably with increasing the Sb cont ents; (iii) the corrosion potential shifted and approached that of pure Sb with time. It is confirmed that the electrochemical behavior of Pb-Sb alloy s is related to the electrochemical property of the individual phase involv ed in the internal galvanic couples formed. (C) 2000 Elsevier Science S.A. All rights reserved.