Investigating the effect of sodium citrate as a corrosion inhibitor on SCC of carbon steel in simulated cooling water by SSRT

Cooling waters are used in many industries for lowering the working temperature of the machineries or parts. Corrosion inhibitors are used to mitigate corrosion of such metallic parts in contact with cooling water. In case these machineries are under stress they may fail due to SCC. Therefore it is necessary to check the susceptibility of metallic parts to SCC in cooling water. The inhibition effect of sodium citrate on SCC of carbon steel in SCW is investigated using SSRT. The stress-strain curves and potential changes showed that citrate ions increase time to failure of carbon steel in presence of 500 ppm chloride ions. Moreover it was observed that the presence of citrate ion is not effective at high concentration of chloride ions i.e. 1000 ppm. The results showed that in presence of citrate ion the toughness was decreased probably due to the prevention of pitting which may increase the elongation.