A hybrid experimental and numerical investigation on the Cr${}_2$AlC-coated zirconium for accident-tolerant fuel systems

This study utilized a hybrid experimental and numerical approach to investigate the failure behavior of zirconium substrates coated with Cr${}_2$AIC. The failure mechanism was determined through a series of interrupted in-situ three-point bending tests in the scanning electron microscope (SEM), covering various stress states. Stress state related parameters for the Cr${}_2$AlC element at coating fracture and zirconium at crack propagation were extracted from finite element numerical simulations. A macroscopic failure criterion was formulated and validated by running numerical simulations and comparing the simulated results with the experimental ones. This work enhances accident-tolerant fuel systems (ATFs) design in nuclear power plants by providing an effective method for characterizing and predicting the failure of zirconium substrates coated with Cr${}_2$AlC and other similar thin films.