Diffusivities of fission gas species in UO2 and (U, Gd)O2 nuclear fuels during irradiation
Diffusivities of fission gas species in UO2 and (U, Gd)O2 nuclear fuels during irradiation
复制标题
UO2 和 (U, Gd)O2 核燃料辐照期间裂变气体种类的扩散度
DOI：
10.1016/0022-3115(95)00091-7
复制
发表时间：
1995
影响因子：
3.1
通讯作者：
R. Williamson
中科院分区：
文献类型：
--
作者：
M. Hirai;J. Davies;R. Williamson
实验测定了Gd掺杂UO_2核燃料在辐照下的裂变气体扩散系数。将含有0、4和8wt%Gd_2O_3的UO_2小样在DIDO堆的扫气装置中进行辐照，测量了裂变气体释放率随温度和扫气氧势的变化规律。在800℃以上，裂变气体在(U，Gd)O_2±x中的扩散系数随温度升高而增大，在800℃以下，扩散系数与温度无关。在所研究的范围内，裂变气体扩散系数对UO_2中的氧势敏感，对4%Gd_2O_3中的氧势不敏感，而对8%Gd_2O_3中的氧势不敏感。在相同的O/M比下，裂变气体在(U，Gd)O_2±x中的扩散系数与Gd_2O_3的含量无关，在低化学计量比区域也与O/M无关，而在高化学计量比区域，裂变气体扩散系数随O/M的增加而急剧增加。
An experiment has been performed to determine fission gas diffusion coefficients in gadolinia-doped UO2nuclear fuels under irradiation. Small specimens of UO2containing 0, 4 and 8 wt% Gd2O3were irradiated in the gas sweep rig of the DIDO reactor and fission gas release rates were measured as a function of temperature and sweep gas oxygen potential. The fission gas diffusion coefficient in (U,Gd)O2±xunder irradiation increased with temperature above 800°C. Below 800°C, the diffusion coefficient appeared to be independent of temperature. Over the range studied here, the fission gas diffusion coefficient was sensitive to oxygen potential in UO2, less sensitive in 4 wt% Gd2O3, and independent of oxygen potential in 8 wt% Gd2O3. The fission gas diffusion coefficient in (U,Gd)O2±xwas judged to be independent of Gd2O3content at the same O/M ratio and also appeared to be independent of O/M in the hypostoichiometric region, whist it increased sharply with increasing O/M in the hyperstoichiometric region.