Preliminary performance evaluation of FeCrAl-ODS steel fuel cladding under accident conditions of BWRs

A preliminary performance evaluation has been performed under accident conditions to compare advantages and disadvantages of application of FeCrAl-ODS steel for the current zirconium-based alloys. Some key material properties of the alloy were also measured for the quantitative evaluations. Under the LOCA condition the FeCrAl-ODS fuel cladding can maintain its mechanical properties beyond the LOCA criteria for the current (zirconium-based alloys) fuel cladding owing to excellent resistances to steam oxidation and thermal shock by water quenching. Moreover, the FeCrAl-ODS fuel cladding can give an additional margin for the fission product release. Under the BDBA condition the FeCrAl-ODS fuel cladding can dramatically reduce the recession rate by both the steam oxidation and the reaction with UO₂. (author)