Assessment of deformation mechanisms in neutron-irradiated accident-tolerant fecral alloys via in situ mechanical testing and TEM analysis


Iron-chromium-aluminum (FeCrAl) alloys are promising as an accident-tolerant fuel cladding for loss-of-coolant accident scenarios; however, limited data are available on the acting deformation mechanisms for this class of materials after neutron irradiation. Here, in situ tensile test experiments were conducted with specimens irradiated at ~1.8 dpa at typical light water reactor temperatures. Selected regions of interest were examined at different strain levels, aiming to investigate the impact of irradiation on acting deformation mechanisms. The fine material microstructure was investigated via transmission electron microscopy. Dislocation structure, radiation-induced defects, and $\alpha$′-phase morphology were investigated in detail and compared with scanning electron microscopy-electron backscatter diffraction and mechanical test results.

In: 19th International Conference on Environmental Degradation of Materials in Nuclear Power Systems - Water Reactors, EnvDeg 2019, pp. 339–345