二氧化铈在铁氦双离子束协同辐照下的缺陷演化行为与机制  

Defect evolution behavior and mechanism of CeO_(2) during Fe^(+) & He^(+) dual-beam synergistic irradiation

作　　者：黄修银 何琨 孙丹 吴璐 辛勇[4] 李奕鹏[1,3] 曹子奇 邱玺 冉广 HUANG Xiu-yin;HE Kun;SUN Dan;WU Lu;XIN Yong;LI Yi-peng;CAO Zi-qi;QIU Xi;RAN Guang(College of Energy,Xiamen University,Xiamen 361102,China;Science and Technology on Reactor Fuel and Materials Laboratory,Chengdu 610041,China;Fujian Research Center for Nuclear Engineering,Xiamen 361102,China;The First Sub-institute,Nuclear Power Institute of China,Chengdu 610041,China)

机构地区：[1]厦门大学能源学院,福建厦门361102 [2]反应堆燃料及材料重点实验室,四川成都610041 [3]福建省核能工程技术研究中心,福建厦门361102 [4]中国核动力研究设计院,四川成都610041

出　　处：《材料热处理学报》2022年第7期183-190,共8页Transactions of Materials and Heat Treatment

基　　金：反应堆燃料及材料重点实验室基金(STRFML-2020-02);国家自然科学基金(11975191,U1967211)。

摘　　要：由于二氧化铈(CeO_(2))与二氧化铀(UO_(2))具有相同的立方萤石晶体结构、几乎相同的晶格参数和相似的物理性质,其常被用作UO_(2)的非放射性模拟燃料,以研究UO_(2)的辐照性能。本论文利用厦门多离子束与透射电镜联机设施,在650℃下采用400 keV Fe^(+)&30 keV He^(+)双离子束对CeO_(2)进行协同辐照;同时在辐照过程中,利用透射电镜(TEM)原位观察和分析了辐照缺陷(位错环和气泡)的演化特征与行为。结果表明:Fe^(+)&He^(+)双束协同辐照导致在CeO_(2)基体中形成了大量的位错环和气泡。在原位研究位错环的萌生、生长、湮灭与合并等行为基础之上,探究了相关机制。随辐照剂量增加,位错环的面密度先增加至峰值后降低,然后达到饱和、趋于稳定;而位错环的平均尺寸随辐照剂量增加总是增大。气泡的平均尺寸先出现一个快速增加,然后保持一个稳定值,随后再增大;而气泡的面密度则是先增加到峰值后再降低。Because cerium dioxide(CeO_(2))has the same cubic fluorite crystal structure,nearly identical lattice parameters and similar physical properties as uranium dioxide(UO_(2)),it is often used as a nonradioactive simulation surrogate fuel of UO_(2) to study the irradiation performance of UO_(2).The evolution characteristics and behavior of irradiation defects(dislocation loops and bubbles)in CeO_(2)foils were investigated by in-situ transmission electron microscopy(TEM)observation during 400 keV Fe^(+) &30 keV He^(+) dual-beam synergetic irradiation at 650℃at the Xiamen Multiple Ion Beam In-situ TEM Analysis Facility(XIAMEN Facility).The results show that a large number of dislocation loops and bubbles are formed in the CeO_(2)matrix by Fe^(+)&He^(+) dual-beam cooperative irradiation.Based on the in-situ study of the initiation,growth,annihilation and combination of dislocation loops,the corresponding mechanisms were explored.With the increase of irradiation dose,the areal number density of dislocation loops first increases to the peak,then decreases,and then reaches saturation and tends to be stable.However,the average size of dislocation loops always increases with the increase of irradiation dose.The average bubble size first increases rapidly,then maintains a stable value,and then increases again,but,the bubble number density first increases to the peak value and then decreases.

关 键 词：二氧化铈 原位辐照 原位电镜 核燃料 辐照行为 

分 类 号：TG132.32[一般工业技术—材料科学与工程] TG139.4[金属学及工艺—合金]