UO2-Mo-Be composites for Accident Tolerant Fuel: SPS fabrication, microcracks-free in as-fabricated state and superior thermal conductivity
UO2-Mo-Be composites for Accident Tolerant Fuel: SPS fabrication, microcracks-free in as-fabricated state and superior thermal conductivity
复制标题
用于事故容忍燃料的 UO2–Mo–Be 复合材料：SPS 制造、制造状态下无微裂纹以及优异的导热性
DOI：
10.1016/j.ceramint.2020.08.064
复制
发表时间：
2020-12-15
影响因子：
5.2
通讯作者：
Yan, Biaojie
中科院分区：
文献类型：
--
作者：
Cheng, Liang;Gao, Rui;Yan, Biaojie
UO_2-Mo复合芯块被认为是高安全要求核反应堆的ATF（事故容忍燃料）系统。然而，由于UO_2和Mo的热膨胀系数（GTE）不匹配，在制造过程中，UO_2-Mo复合材料将产生残余应力。制备了一种新型的UO 2-Mo-Be复合芯块，以减小由于GTE失配而引起的残余应力。解决了高钼含量球团中热膨胀系数失配引起的应力引起的微裂纹问题。与纯UO 2相比，UO 2 - 9 Mo-6 Be复合材料的热导率在298 K和1273 K分别提高了128.65%和157.71%。UO_2 - 6 Mo-4 Be复合材料的热导率也高于文献报道的UO_2 - 10 BeO复合材料和UO_2 - 10 Mo复合材料。虽然没有进行辐照试验，但这种UO 2-Mo-Be复合材料有望成为ATF的最佳候选燃料系统。
UO2-Mo composite pellets have been considered as an ATF (Accident Tolerant fuel) system for a nuclear reactor with high-safety-requirement. Nevertheless, since the mismatch of coefficient of thermal expansion (GTE) between UO2 and Mo, residual stresses will be produced in UO2-Mo composites during manufacturing. A novel type of UO2-Mo-Be composites pellets is fabricated to reduce the residual stresses caused by the mismatch of GTE. As a result, the problem of micro-cracks behavior caused by the CTE mismatch-induced stress in pellets with high Mo incorporation has been resolved. Compared with the pure UO2, the thermal conductivity of UO2 -9Mo-6Be composites is increased by 128.65% at 298 K and 157.71% at 1273 K, respectively. The thermal conductivity of UO2-6Mo-4Be composites is also higher than that of UO2-10BeO composites and UO2-10Mo composites published in the literatures. While no irradiation test has been performed, such UO2-Mo-Be composites are expected to be an optimized candidate fuel system as an ATF.