Mechanical Behavior of FeCrAl and Other Alloys Following Exposure to LOCA Conditions Plus Quenching

摘要

The US Department of Energy is working with commercial fuel vendors to develop advanced technology or accident tolerant fuels (ATF) for the current fleet of light water power reactors. General Electric and Oak Ridge National Laboratory are evaluating the concept of using iron-chrome-aluminum (FeCrAl) alloys as cladding for the current fuel of uranium dioxide pellets. In the case of a loss of coolant accident, the reactor may need to be flooded with fresh water when the cladding could be in the temperature range above 1000 °C. It is important to determine the integrity of the cladding material after being quenched in water. Tests were performed for six alloys of interest which were exposed for 2 h at 1200 °C in air, argon or steam and then quenched in ambient temperature water. The resulting mechanical properties were evaluated and compared with the mechanical properties of the as received material. The FeCrAl alloy retains its yield strength after the high temperature excursions, with minimal oxidation but with some loss of ductility.