Polarization resistance studies on Corrosion inhibition of 304 austenitic and 430 ferritic stainless steels in H2SO4 solutions

✍ Scribed by Hamid A. Al-Megren; Dr. Abdulaziz A. Al-Suhybani

• Publisher: John Wiley and Sons
• Year: 1993
• Tongue: English
• Weight: 527 KB
• Volume: 24
• Category: Article
• ISSN: 0933-5137
• DOI: 10.1002/mawe.19930240116

✦ Synopsis

Abstract

The corrosion of 304 Austenitic and 430 Ferritic Stainless steels in sulphuric acid solutions has been investigated using polarization resistance (Rp) technique. Different organic inhibitors were used in this study and these contain an allylic group (CH~2~  CH~2~ ). The effect of acid and inhibitor concentrations, temperature, and addition of chloride ion was studied. Acid concentration was varied between 2 and 12 M and the reaction rate was found to be maximum at approximately 6 M. The inhibition efficiencies of various compounds were found to depend on concentration and varies from one alloy to another. For 304SS the efficiency lies between 40–100%. For 430SS some of these compounds behave as corrosion accelerator at certain concentrations and inhibitors at others. Chloride ion was found to improve considerably the inhibition efficiency with some exceptions. Various kinetic parameters were evaluated and they are reported. In addition the reaction mechanism is briefly discussed.