Corrosion behavior of austenitic and ferritic/martensitic steels in oxygen-saturated liquid Pb-Bi eutectic at 450C and 550C

Kurata, Yuji; Futakawa, Masatoshi  ; Saito, Shigeru   

Static corrosion tests of various austenitic and ferritic/martensitic steels were conducted in oxygen-saturated liquid Pb-Bi at 450C and 550C for 3000h to study the effects of temperature and alloying elements on corrosion behavior. Oxidation, grain boundary corrosion, dissolution and penetration were observed. The corrosion depth decreases at 450C with increasing Cr content in steels regardless of ferritic/martensitic or austenitic steels. Appreciable dissolution of Ni and Cr does not occur in the three austenitic steels at 450C. The corrosion depth of ferritic/martensitic steels also decreases at 550C with increasing Cr content whereas the corrosion depth of austenitic steels, JPCA and 316ss becomes larger due to ferritization caused by dissolution of Ni at 550C than that of ferritic/martensitic steels. An austenitic stainless steel containing about 5%Si exhibits fine corrosion resistance at 550C because the protective Si oxide film is formed and prevents dissolution of Ni and Cr.