New experimental size distributions were presented for interstitial-type dislocation

loops in (U,Pu)O2 samples after 4 and 7 years of self-irradiation along with a new

model. For this model, the work of Hayns was extended to doped materials and to

take into account additional phenomena, namely re-solution and coalescence as

applied to gas bubble precipitation. The calculations were compared to the

experimental size distributions obtained by means of transmission electron

microscopy for two different storage times. The role of re-solution and coalescence

was discussed based on this model. This constitutes a basis for modelling the high

burn-up structure formation which was a consequence of the accumulation of

radiation damage in nuclear fuels.

Growth Mechanisms of Interstitial Loops in Α-Doped UO2 Samples. J.Jonnet,

P.Van Uffelen, T.Wiss, D.Staicu, B.Rémy, J.Rest: Nuclear Instruments and

Methods in Physics Research B, 2008, 266[12-13], 3008-12