Corrosion resistance of a cast steel overpack for high-level radioactive waste disposal in Japan

Ogawa, Yusuke*; Suzuki, Satoru*; Taniguchi, Naoki ; Kawasaki, Manabu*; Suzuki, Hiroyuki*; Takahashi, Rieko*

Cast steel is one of the promising alternative to forged steel that is the current reference material for carbon steel overpack. In this study, the full-scale cast steel overpack was produced experimentally and the distribution of casting defects were investigated. The corrosion test regarding corrosion rate and stress corrosion cracking (SCC) susceptibility were also conducted using samples taken from the full-scale cast steel overpack and the corrosion resistance of cast steel was compared with that of forged steel. From above two corrosion tests, it can be said that the corrosion resistance of cast steel is mostly the same as that of forged steel.