基于蒙特卡罗模拟研究锆钛酸铅镧材料的中子辐照损伤  

Simulation of neutron irradiation damage in lead lanthanum zirconate titanate by Monte Carlo method

作　　者：王丽敏 段丙皇 许献国[2] 李昊 陈治军 杨坤杰 张硕 Wang Li-Min;Duan Bing-Huang;Xu Xian-Guo;Li Hao;Chen Zhi-Jun;Yang Kun-Jie;Zhang Shuo(School of Nuclear Science and Technology,Lanzhou University,Lanzhou 730000,China;Institute of Electronic Engineering,China Academy of Engineering Physics,Mianyang 621900,China;College of Nuclear Equipment and Nuclear Engineering,Yantai University,Yantai 264005,China)

机构地区：[1]兰州大学,核科学与技术学院,兰州730000 [2]中国工程物理研究院,电子工程研究所,绵阳621900 [3]烟台大学,核装备与核工程学院,烟台264005

出　　处：《物理学报》2022年第7期281-289,共9页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:11875154,12005200);中央高校基本科研业务费专项资金(批准号:lzujbky-2019-13)资助的课题;兰州大学超算中心支持。

摘　　要：锆钛酸铅镧(Pb_(0.94)La_(0.06)Zr_(0.96)Ti_(0.04)O_(3),PLZT)具有良好的介电和储能性质,是高效、高能量密度电容元件和存储器件的基体材料.为研究该材料的中子辐照损伤,首先基于Geant4程序包模拟了能量为1-14 MeV中子辐照浩钛酸铅镧(PLZT)材料产生的反冲原子能谱,然后根据产生的反冲原子种类和最大能量,利用二元碰撞方法模拟了不同能量的离子在PLZT中产生的位移损伤(包括空位和间隙原子),最后根据反冲原子能谱和对应能量离子在材料中产生的缺陷数目计算了不同能量的中子在PLZT材料中产生缺陷浓度以及分布.结果发现,对于1-14 MeV能区的快中子而言,其在厚度为3 cm的PLZT材料中产生的缺陷数目近似与中子能量无关,约为460±120空位/中子.辐照损伤在3cm厚度内随深度的增加而略有减小,总体变化小于50%,该减小主要是由于中子的反散射导致.本工作为计算中子在材料中的位移损伤提供了一种方法,同时模拟结果可为研究PLZT基电子器件的中子辐照效应提供指导.Lead lanthanum zirconate titanate(PLZT)has a broad application prospect for energy storage devices with high energy density,since it possesses excellent dielectric and energy storage properties.To investigate the irradiation damage to the PLZT induced by neutrons with different energy,the primary energetic recoil spectra of each kind of element are first extracted from the transportation simulations of neutrons with energy ranging from 1 to 14 MeV,respectively.Then,the displacement damages(including vacancies and interstitial atoms)induced by each type of recoil with different energy are simulated based on the binary collision approximation method.Finally the number of defects in PLZT produced by neutrons with an energy range from 1 to 14 MeV is calculated based on the recoil energy spectra and the defect number produced by the recoils.The results show that the number of defects produced in the PLZT material with a thickness of 3 cm is approximately independent of the neutron energy for the fast neutrons with energy in a range from 1 to 14 MeV,even though the primary recoil energy spectra from neutrons with different energy are completely different.The average number of defects produced in 3-cm-thick PLZT is about 460±120 vacancies/neutrons.For neutrons with energy ranging from 1 to 14 MeV,the produced defect concentration in PLZT decreases slightly with the depth increasing within a thickness of 3 cm.The difference in defect concentration in this 3 cm is in a range of 50%.This decrease is caused mainly by the fact that some of neutrons are back-scattered during transport.The average defect concentration produced by neutron irradiation in the PLZT with a thickness of 3 cm is slightly(~20%)higher than that in the PLZT with a thickness of 1 mm.The reason for the higher defect concentration in a thicker(3 cm)PLZT can be attributed to the following facts:(ⅰ)the(n,2 n)reactions between neutron and material can make the number of neutrons increase during transport;(ⅱ)the scattering can make the path of neutron lon

关 键 词：锆钛酸铅镧 蒙特卡罗模拟 中子辐照损伤 缺陷浓度 

分 类 号：TL329.2[核科学技术—核技术及应用]