SEM images (BSE mode) of a polished cross-section of the 50/50-t5 sample – (a) general view of an area where most of the U-5Al particles are transformed into UAl₃, (b) enlarged view of particles containing the UAl₃ (positions 1 and 2) and UAl₄ phases (positions 3, 4 and 5). The Al content (at ±2 at.%) at positions 1 to 5 was measured by EDS. The U content corresponds to the complement to 100%.