Application of cathodic protection of stainless steel for components in fuel reprocessing plant

Ueno, Fumiyoshi  ; Uchiyama, Yohei*; Kato, Chiaki   ; Yamamoto, Masahiro ; Ebina, Tetsunari*; Shimogawara, Shigeru*; Kano, Yoichi*

An application of cathodic protection method with impressed current system to control corrosion of austenitic stainless steel in boiling nitric acid solution was studied to improve corrosion resistance of components in fuel reprocessing plant. Plate and tube type specimens made of ultra low carbon type 304 stainless steel (SUS304ULC) were immersed in boiling nitric acid solutions using electrochemical test cells, electrochemical potentiostatic tests and cathodic protection tests were performed. Corrosion rates in the solution with and without protection were measured. As the results, corrosion rates of plate type specimens with cathodic protection were decreased from 1/40 to 1/10 against without protection. In the case of tube type specimen, loss of outer surface thickness was decreased about 1/8, and no deviation of the loss was observed. Authors were concluded that cathodic protection method was expectative as one of the maintenance methods of components in fuel reprocessing plant.