| Abstract: | Inhibition of the corrosion of 63/37 brass in ammonium chloride solutions Potassium chromate, dichromate, ferrocyanide and thiocynate have been investigated as inhibitors corrosion 63/37 brass in 0.005 M and 0.01 M ammonium chloride solutions. Nearly complete protection is afforded to brass by potassium chromate at all the durations studied. Potassium thiocynate is more effective in 0.01 M ammonium chloride rather than in 0.005 M ammonium chloride. In the case of potassium thiocyanate and potassium ferrocyanide, the efficiency is maximum at the optimum concentration of the inhibitor, further increase in inhibitor concentration induces a decrease in inhibitor efficiency. Both these substances afford protection by mixed control. Potassium dichromate is a mixed type of inhibitor with a predominant action on the local cathodic areas. Potassium chromate retards the corrosion by influencing both cathodic and anodic reactions, cathodic to a greater extent. |
