Abstract The Advanced Gas Reactor Fuel Qualification and Development Program's second irradiation experiment focuses on the performance of fuel particles produced in an industrial-scale coating system. Ongoing post-irradiation examination efforts include exploration of tristructural-isotropic (TRISO)-coated particle fuel in the as-irradiated state and subjected to elevated temperatures to simulate accident conditions (safety testing). Scanning electron microscopy (SEM) analysis with energy dispersive x-ray spectroscopy (EDS) was used to show the distribution of fission products within the TRISO layers. The SEM analysis showed a variation of fission product distribution within the TRISO layers based on irradiation temperature, burnup, individual particle fission product inventory retention, safety testing history and kernel composition. A key observation is that particles which likely experienced higher temperature showed a greater diversity and distribution of fission products and actinides in the IPyC and SiC layers, implying that temperature is a dominant variable influencing the transport of radionuclides in TRISO particles.

中文翻译：

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AGR-2燃料TRISO层裂变产物分布和成分分析

摘要 先进气体反应堆燃料鉴定和开发计划的第二次辐照实验侧重于工业规模涂层系统中生产的燃料颗粒的性能。正在进行的辐照后检查工作包括探索处于辐照状态并经受高温以模拟事故条件（安全测试）的三结构各向同性 (TRISO) 涂层颗粒燃料。使用能量色散 X 射线光谱 (EDS) 的扫描电子显微镜 (SEM) 分析来显示 TRISO 层内裂变产物的分布。SEM 分析显示 TRISO 层内裂变产物分布的变化基于辐照温度、燃耗、单个粒子裂变产物库存保留、安全测试历史和内核组成。