Effect of Grain Size on Microstructural Change and Damage Recovery in UO2 Fuels Irradiated to 23 GWd/t

Kazuhiro Nogita, Katsumi Une

Research output: Contribution to journalArticlepeer-review

15 Citations (Scopus)


The effect of grain size on microstructural change and damage recovery in U02 fuels was studied by X-ray diffractometry (XRD) and transmission electron microscopy (TEM). The as-irradiated lattice parameter of the standard fuel (grain size: 16 /im) was larger than that of the large-grained fuel (43 μm), indicating a larger number of fission-induced point defects in the lattice of the former fuel. This tendency was in contrast to previously reported results for low burnup fuels below 1 GWd/t. The lattice dilation in the present high burnup fuels was mainly due to the accumulation of vacancies. The lattice parameter of both fuels began to recover around an irradiation temperature of 450~650°C, and both had a complete recovery at 850°C. On annealing at high temperatures of 1,450~1,800°C, the bubble diameter in the standard fuel was larger than that in the large-grained fuel. This indicated that vacancy diffusion from the grain boundaries plays an important role during bubble coarsening at high temperatures.

Original languageEnglish
Pages (from-to)929-936
Number of pages8
Journaljournal of nuclear science and technology
Issue number9
Publication statusPublished - Sep 1994

All Science Journal Classification (ASJC) codes

  • Nuclear and High Energy Physics
  • Nuclear Energy and Engineering


Dive into the research topics of 'Effect of Grain Size on Microstructural Change and Damage Recovery in UO<sub>2</sub> Fuels Irradiated to 23 GWd/t'. Together they form a unique fingerprint.

Cite this