Access the full text.
Sign up today, get DeepDyve free for 14 days.
[Austenitic stainless steel (SS) 304L is currently the preferred material for fabrication of critical components in reprocessing plants. These components are exposed to highly corrosive process fluid consisting of boiling nitric acid that contains oxidizing fission and corrosion products. With continuous and prolonged recirculation operation, there is an increase in the concentration of nitric acid and/or a build-up of highly oxidizing ions consisting of fission products, transuranium elements, uranium and corrosion products in the process fluid. This increases the operating potential, and once it exceeds the transpassive potential of SS, severe intergranular corrosion (IGC) of even non-sensitized SS occurs due to transpassive dissolution. This paper shows two cases of typical degradation due to IGC of non-sensitized SS 304L. The paper also reviews and evaluates alternate materials (titanium- and zirconium-based alloys) for use in reprocessing plants for such applications. Ti-Al-Zr alloy and zircaloy-4, both developed indigenously in India, can be considered for tube material in thermosyphon evaporators. Corrosion evaluation of Ti-grade 2, Zr-grade 702, Ti-Al-Zr and zircaloy-4 was performed using immersion tests and electrochemical polarization at both ambient and elevated temperatures up to 3 VSCE. These results were also compared with that obtained for SS 304L exposed under similar conditions. Based on the investigations, it is concluded that both Ti-Al-Zr and zircaloy are suitable for use in boiling nitric acid when it contains high concentration of oxidizing ions. Among the different alloys analysed, the best corrosion resistance was observed for Zr-grade 702 and zircaloy-4.]
Published: May 5, 2022
Keywords: Nitric acid service; Fission products; Operating potential; Stainless steel; Ti-based alloy; Zr-based alloy
Read and print from thousands of top scholarly journals.
Already have an account? Log in
Bookmark this article. You can see your Bookmarks on your DeepDyve Library.
To save an article, log in first, or sign up for a DeepDyve account if you don’t already have one.
Copy and paste the desired citation format or use the link below to download a file formatted for EndNote
Access the full text.
Sign up today, get DeepDyve free for 14 days.
All DeepDyve websites use cookies to improve your online experience. They were placed on your computer when you launched this website. You can change your cookie settings through your browser.