Microstructural Changes of AlOOH Doped UO₂ Pellet during the Annealing Process

Microstructural changes of AlOOH doped UO₂ pellet after annealing up to 216 h have been observed and they were compared with those of the standard pellet. Grain and pore size of UO₂ pellet increased with the addition of AlOOH and its effect was still validated during annealing. Densification rate was reduced by the addition of AlOOH and it was attributed to coarsened pores with spherical shape. Grain and pore growth was stopped and density increase was the least after 144 h of annealing. The variation of pore size resulting from annealing has a linear relationship with that of grain size.