摘要
在高燃耗率时,作为裂变产物的镧系元素(主要为La,Ce,Pr,Nd,Pm,Sm)在合金燃料内部不断积累,并且逐渐迁移至包覆层-燃料界面,与包覆层主要化学元素(Fe,Cr,Ni)发生化学反应,生成低熔点金属间化合物。控制包覆层-燃料界面化学反应的有效措施之一是将特定化学元素掺入合金燃料中,与镧系元素发生化学反应,生成稳定的、难以迁移的化合物,从而显著减少或延迟包覆层-燃料界面化学反应的发生。铟(In)由于具有与合金燃料元素相容、对包覆层金属元素呈现化学惰性以及与镧系元素能够生成金属间化合物等特性,已作为合金燃料的化学掺杂剂而被研究。本工作通过第一性原理计算,研究了铟-镧系元素(In-La)金属间化合物(InLa,CeIn3,αInPr,In 3Nd)的基态性质以及在自旋-轨道耦合存在下的电子和磁性性质;此外,基于Debye-Slater模型,对InLa、CeIn3、αInPr、In3Nd在不同温度和压力下的热力学性质进行了计算。该研究可更好地表征铟结合和稳定镧系裂变产物的功能。
At high burnup,fission product lanthanide accumulate is substantial and obviously contributes to fuel-cladding chemical interaction upon migration to the Fe-based cladding interface.By doping with specific elements into the fuel alloy,the lanthanide accumulates may be precipitated into stable,non-migratory,and non-reactive phases within the fuel and thus significantly reduce and/or delay the onset of fuel-cladding chemical interaction.Experimentally,indium has been selected as the fuel dopant due to several attractive properties,such as its compatibility with the fuel,chemical inertness with cladding materials and reactivity with the lanthanides.In this study,first-principles calculations were performed to investigate ground-state properties of the indium-lanthanides(La,Ce,Pr and Nd)intermetallic compounds.The electronic and magnetic properties of InLa,CeIn 3,αInPr and In 3Nd have been calculated in the presence of spin-orbit coupling,and anti-ferromagnetic ground state structures have been found to be the most stable phases for these compounds.In addition,the thermodynamic properties of these four compounds at given temperatures and pressures have been calculated.The study may lead to a better understanding of the function of indium of binding and stabilizing lanthanide fission products.
作者
徐允
张兆春
郭海波
谢耀平
XU Yun;ZHANG Zhaochun;GUO Haibo;XIE Yaoping(School of Materials Science and Engineering,Shanghai University,Shanghai 200444,China)
出处
《材料导报》
EI
CAS
CSCD
北大核心
2020年第2期2093-2099,共7页
Materials Reports
关键词
铟
镧系元素
磁学
热力学性质
第一性原理
indium
lanthanide
magnetic
thermodynamic properties
first-principles calculation
作者简介
徐允,现为上海大学材料科学与工程学院硕士研究生。目前主要研究领域为:基于第一性原理研究铟与金属核燃料裂变产物镧系元素相互作用及其产物的物理化学性质;张兆春,上海大学材料科学与工程学院副教授。主要研究方向包括:金属和半导体纳米体系的制备与其功能化实验研究;低维碳材料结构设计及其物理化学性质研究。自2000年至今,主持、参与上海市高等学校科学技术发展基金项目和国家自然科学基金项目共计5项;发表学术研究论文60余篇,专利授权2项,zhangzhaochun@shu.edu.cn。
