Anode behavior of lead-antimony alloy ssu3 with potassium in nacl electrolyte environment

The results of a corrosion-electrochemical study of the effect of potassium additives, as a structure modifier, on the anodic behavior of the SSu3 lead alloy in the NaCl electrolyte environment are presented. The study was carried out by the potentiostatic method in the potentiodynamic mode at a potential sweep rate of 2 mV / s, in the NaCl electrolyte environment with a concentration of 0.03; 0.3 and 3.0% wt. It was found that with an increase in the concentration of chloride ion in a NaCl electrolyte, a shift in the negative region of the values of corrosion, pitting formation and repassivation potentials of the SSu3 alloy with potassium is observed. The potential of free corrosion of alloys with time shifts to the positive value region. This dependence is also characteristic with an increase in the concentration of potassium in the lead alloy SSu3. The addition of potassium to the SSu3 alloy increases its corrosion resistance by 30%. At the same time, regardless of the composition of the alloys, an increase in the rate of their corrosion with the concentration of NaCl in the electrolyte was established. It is shown that the alloys corrode as a pitting mechanism, and potassium as a modifier of the alloy structure contributes to the shift of the pitting and repassivation potentials to the region of positive values. This, in turn, leads to an increase in resistance of the alloys to pitting corrosion, and also contributes to the healing of incipient pitting foci.