Distribution of fission products palladium, silver, cerium and cesium in the un-corroded areas of the locally corroded SiC layer of a neutron irradiated TRISO fuel particle
Distribution of fission products palladium, silver, cerium and cesium in the un-corroded areas of the locally corroded SiC layer of a neutron irradiated TRISO fuel particle
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中子辐照 TRISO 燃料颗粒局部腐蚀 SiC 层未腐蚀区域中裂变产物钯、银、铈和铯的分布
DOI：
10.1016/j.jeurceramsoc.2017.04.012
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发表时间：
2017
影响因子：
5.7
通讯作者：
I. V. Rooyen
中科院分区：
文献类型：
--
作者：
Haiming Wen;I. V. Rooyen
详细的电子显微镜研究进行调查的裂变产物的分布和组成的三结构各向同性涂层颗粒表现出局部腐蚀的SiC层。以前的研究表明，这种颗粒在SiC层中的纯碳区域，导致局部腐蚀的SiC由Pd，提供途径的Ag，Cd，和Cs的迁移。这项研究揭示了在未腐蚀的SiC区域中存在含Ag和/或Cd的沉淀物。Ag和Cd可以单独存在或与Pd共存。Ag和Cd主要沿沿着SiC晶界迁移。在SiC晶粒内的堆垛层错处发现了Ag-Pd-Cd沉淀物，这表明Ag和Cd的晶内运输是可能的。在一些沉淀物中，Ce与Pd或Pd-U一起存在。U和Ce经常共存，而Ag和Cd通常不与U或Ce共存。在检查区域的任何沉淀物中均未检测到Cs。
Detailed electron microscopy studies were performed to investigate distribution and composition of fission products in the SiC layer of a tristructural-isotropic-coated particle exhibiting localized corrosion. Previous studies on this particle indicated that pure carbon areas in the SiC layer, resulting from localized corrosion of SiC by Pd, provide pathways for Ag, Cd, and Cs migration. This study reveals the presence of Ag- and/or Cd-containing precipitates in un-corroded SiC areas. Ag and Cd may exist by themselves or coexist with Pd. Ag and Cd mainly transport along SiC grain boundaries. An Ag-Pd-Cd precipitate was identified at a stacking fault inside a SiC grain, suggesting that intragranular transport of Ag and Cd is possible. Ce is present with Pd or Pd-U in some precipitates. U and Ce frequently coexist, whereas Ag and Cd usually do not coexist with U or Ce. No Cs was detected in any precipitates in the areas examined.