The direct incorporation of Gd2O3 powder into UO2 powder by dry mechanical blending
is the most attractive process for producing UO2-Gd2O3 nuclear fuel. However, previous
experimental results by our group indicated that pore formation due to the Kirkendall effect delays
densification and, consequently, diminishes the final density of this type of nuclear fuel.
Considering this mechanism as responsible for the poor sintering behavior of UO2-Gd2O3 fuel
prepared by the mechanical blending method, it was possible to propose, discuss and, in certain
cases, preliminarily test feasible adjustments in fabrication procedures that would minimize, or even
totally compensate, the negative effects of pore formation due to the Kirkendall effect. This work
presents these considerations.