Defective structures in FeCrAl alloys from first principles calculations

The FeCrAl alloy system is well known as a potential candidate material for the accident tolerant fuel (ATF) cladding in the nuclear power industry owing to its high oxidation resistance under irradiation and high-temperature environment. The mechanical properties of FeCrAl alloys with various defects degrade under irradiation condition. In the present work, the structures of FeCrAl alloys with 10 ∼ 15Cr wt% and 5 ∼ 6Al wt% were simulated from the first principles calculations. Mechanical properties were predicted for FeCrAl alloys with different defects and components. Calculated results showed that doping Cr into alloys may improve its mechanical properties. On the other hand, Al was predicted to downgrade the mechanical properties by replacing the Fe atom. The mechanical anisotropies of FeCrAl were researched through Zener's index and 3D Young's modulus sketches. Additionally, the investigation on electronic characteristics indicated that an attenuated Fe–Fe interaction and strengthened Fe–Al interactions occur with the addition of Al.