R&D on nitride fuel cycle for MA transmutation to enhance safety and economy, 5; Chemical compatibility between cladding and fuel surrogate materials

Harada, Makoto; Takaki, Seiya  ; Takano, Masahide 

T91 ferrite steel is considered as cladding of nitride fuels for transmutation of Minor Actinides. In this study, chemical compatibility between cladding and fuel surrogate materials was investigated in two different conditions. One condition was in over melting point of cladding and in short term. The other condition was in predicted operation temperature (773K, 923K, 1023K) and in long term. Surrogate fuel materials were ZrN and DyZrN, and cladding materials were T91 and SUS316L steel. After the reaction tests, cross sections of specimens were examined by SEM/EDS to characterize the extent of reaction and diffusion. In the melting test, reaction layers didn't exist, but some particles of surrogate fuel materials were observed in cladding layer. In predicted operation temperature test, all specimen had no reaction layers. In conclusion, cladding and fuel surrogate materials have excellent chemical compatibility.