Dissolution behavior of SUS304 stainless steel into Fe-Cr-Ni-B-C alloy

As a consequence of severe accident in Fukushima Dai-ichi nuclear power plant, the fuel debris was formed at the bottom of reactor container due to the reaction between the dropping corium and structural stainless steel. To assess the access route to the fuel debris for its removal, corrosion condition of the structural stainless steel should be well understood. In this study, the SUS304 stainless steel and Fe-Cr-Ni-B-C alloy were employed to investigate the corrosion behavior. By immersion experiment, the diffusion coefficient of boron into the SUS304 stainless steel was estimated. The dissolution time of SUS304 stainless steel rod into the liquid alloy was predicted.