Effects of Burnup on Certain Ceramic Fuel Materials

Dispersion Fuels

“…When most or all of the matrix material is subjected to recoil, such as in dispersions containing small fuel particles and/or high fuel volume fractions, complete amorphization or mictametization of the ceramic matrix may occur. This phenomenon happens at very low exposures in the noncubic compounds mentioned above and may be accompanied by a large volume increase, as much as 20% in A1 2 O 3 that contained fine UO 2 particles (Bleiberg et al, 1961). The mictametized material is apparently very plastic under irradiation, allowing growth of large bubbles of recoiled fission gas when burnup progresses, as shown in Fig.…”