b'Figure 1. A montage backscattered electron (BSE) image shows the entire cross section of the examined fuel sample (a). High magnification BSE images of observed interaction (as red arrows denoted) between the Cr diffusion barrier and fuel periphery (b)-(f). A BSE image shows the preserved Cr diffusion barrier (g). The green and red lines in (g) show the locations for thickness measurements of the preserved Cr diffusion barrier using ImageJ software, with results tabulated in (h)2023|AFC ACCOMPLISHMENTS 165'