基于沉淀相粗化机制的裂变气泡长大模型研究  

Research on Model of Fission Gas Bubble Growth Based on Oswald Ripening Mechanism

作　　者：龙冲生[1] 张雨[1] 陈洪生[1] 肖红星[1] 韦天国[1] 赵毅[1] 

机构地区：[1]中国核动力研究设计院反应堆燃料与材料重点实验室,成都610213

出　　处：《核动力工程》2016年第5期43-45,共3页Nuclear Power Engineering

基　　金：国家自然科学基金(91226114)

摘　　要：基于合金中沉淀相粗化机制,建立了裂变气泡(FGB)长大的数学模型,以铀合金和陶瓷UO_2燃料为例,计算了在不同辐照温度和外压约束下气孔率、平均孔径随燃耗深度的变化。对UO_2燃料,当外压约束相同时,在700°C下的气孔率增长速度比400°C下的约快25%;外压约束对FGB的长大有一定抑制作用,但影响相对较小。由于金属燃料易于发生塑性变形,在同样的燃耗下,气孔率和平均孔径都显著大于陶瓷燃料。Based on the Ostwald ripening process, a mechanistic model for the fission gas bubble growth has been proposed in this paper. Taking U-Zr alloy and UO_2 ceramic fuel as samples, the variation of FGB porosity and mean bubble size with the burn-up at different irradiation temperature and external restraint have been investigated in detail. For ceramic UO_2, the porosity increase rate with the burn-up at 700°C is 25% faster than that at 400°C. The external restraint impedes the growth of FGB, but it is not very significant. The porosity and mean bubble size in U-Zr alloy for the same irradiation parameters are much greater than that in the ceramic UO_2 because the plastic deformation takes place very easy and quickly for U-Zr alloy during irradiation.

关 键 词：裂变气体气泡 长大 机理模型 沉淀相粗化机制 

分 类 号：TL329.2[核科学技术—核技术及应用]