Anode behavior of SSu3 lead alloy with zinc, in the medium of electrolyte NaCl
The results of a corrosion-electrochemical study of the effect of zinc additions as an alloying component on the anodic behavior of a lead alloy of the SSu3 grade (Pb + 3.0 % (by mass) Sb) in an electrolyte medium NaCl are presented. The anodic behavior of the alloys was investigated by the potentiostatic method in the potentiodynamic mode at a potential sweep rate of 2 mV/s. The zinc content in the SSu3 alloy was 0.01 - 0.50 % (by weight). The studies were carried out in an electrolyte environment of NaCl with a concentration of 0.03; 0.30 and 3.00% (by weight). It was found that with an increase in the concentration of chloride ion in the NaCl electrolyte, a shift in the negative region of the values of the corrosion, pitting formation and repassivation potentials of alloys is observed. The potential for free corrosion of alloys, depending on the length of time, shifts to the positive region. This dependence is also characteristic with an increase in the concentration of zinc in the SSu3 alloy. Regardless of the composition of the alloys, an increase in the rate of their corrosion with an increase in the concentration of NaCl in the electrolyte was established. The addition of zinc to the SSu3 alloy increases its corrosion resistance. It is shown that the alloys corrode by the pitting mechanism and zinc, as an alloying component of the SSu3 alloy, promotes the shift of the pitting and repassivation potentials to the region of positive values. This leads to an increase in the resistance of alloys to pitting corrosion, and also contributes to the healing of incipient pitting foci.