Understanding irradiation assisted hydrogen embrittlement using in situ Bragg coherent diffraction imaging

This proposal aims to utilize Bragg coherent diffraction imaging (BCDI) at the ID01 beamline to understand the radiation-assisted hydrogen embrittlement (HE) mechanism in model binary single crystal alloy of Fe-Cr prepared by dewetting. Three-dimensional coherent X-ray diffraction patterns will be used to image the hydrogen-induced strains and domains. We will quantify the time-dependent lattice parameter and strain-induced during hydrogen charging. This will be combined with thermal desorption spectroscopy spectra collected ex-situ to understand the diffusion mechanisms during hydrogen absorption. In addition, we will compare the effect of hydrogen charging time and Fe ion irradiation on the defects-assisted HE formation mechanism within Fe and Fe-Cr microcrystals. Such a systematic study using model systems such as Fe and Fe-Cr will unravel the role of alloying elements in slowing down HE in steels.