Mun Seung Uk, Oh Gun, Kim Jun Hwan, Park Sang-Gyu, Weon Byung Mook
Soft Matter Physics Laboratory, School of Advanced Materials Science and Engineering, Sungkyunkwan University, 2066 Seobu-ro, Jangan-gu, Suwon, Gyeonggi-do, 16419, Republic of Korea.
Research Center for Advanced Materials Technology, Sungkyunkwan University, 2066 Seobu-ro, Jangan-gu, Suwon, Gyeonggi-do, 16419, Republic of Korea.
Sci Rep. 2024 Aug 21;14(1):19402. doi: 10.1038/s41598-024-69935-x.
Metallic fuel is being developed for the next generation of sodium-cooled fast reactors due to its safety and fuel cycle economics through spent fuel reprocessing technology. After spent fuel reprocessing, rare earth elements that are immiscible with Uranium and Zirconium are included in the raw material for metallic fuel. Achieving a uniform composition and microstructure of RE inclusions is challenging because phase separation and temperature inhomogeneities during solidification lead to non-uniform composition and microstructure. This study explores the solidification and inclusion formation of U-Zr-RE metallic fuel rods. We show how RE inclusions are formed in the U-Zr matrix and how temperature inhomogeneities during solidification control the inclusion size distribution and edge migration of RE inclusions along the U-Zr-RE rods. Understanding the inhomogeneity of inclusions due to solidification can provide hints for making homogeneous nuclear fuel rods.
由于金属燃料通过乏燃料后处理技术具有安全性和燃料循环经济性，因此正在为下一代钠冷快堆开发金属燃料。在乏燃料后处理之后，与铀和锆不混溶的稀土元素被包含在金属燃料的原料中。由于凝固过程中的相分离和温度不均匀性会导致成分和微观结构不均匀，因此实现稀土夹杂物的均匀成分和微观结构具有挑战性。本研究探索了U-Zr-RE金属燃料棒的凝固和夹杂物形成过程。我们展示了稀土夹杂物如何在U-Zr基体中形成，以及凝固过程中的温度不均匀性如何控制稀土夹杂物沿U-Zr-RE棒的尺寸分布和边缘迁移。了解由于凝固导致的夹杂物不均匀性可以为制造均匀的核燃料棒提供线索。
