新型中子/γ射线屏蔽材料的设计和制备  

Design and preparation of novel neutron/γ-ray shielding materials

作　　者：吴早明 庞晓轩[1] 刘向东 鲜亚疆 罗昊 程亮[1] 严春雷 Wu Zaoming;Pang Xiaoxuan;Liu Xiangdong;Xian Yajiang;Luo Hao;Cheng Liang;Yan Chunlei(Institute of Materials,China Academy of Engineering Physics,Mianyang 621907)

机构地区：[1]中国工程物理研究院材料研究所,绵阳621907

出　　处：《化工新型材料》2024年第2期145-150,共6页New Chemical Materials

基　　金：国防科工局(FRL202001)。

摘　　要：屏蔽材料设计主要考虑中子和γ射线的防护需求,兼具中子和γ射线协同防护作用的材料,可广泛应用于诸多辐射场景。介绍了屏蔽材料的种类、优势和不足,并基于蒙特卡罗粒子输运软件(MCNP)程序开展了针对中子和γ射线屏蔽材料的设计和优化研究工作,提出了一种具有较好屏蔽效果的新型中子和γ射线屏蔽材料设计方案。模拟结果表明在石蜡中添加一定量的B_(4)C可显著提高材料对中子的屏蔽率,其中,B_(4)C添加质量为10%~20%的含硼石蜡具有较优异的中子屏蔽效果,75mm含硼(10%B_(4)C)石蜡/1mm Pb等多层屏蔽材料设计对Pu自发裂变中子的总能量屏蔽率为96.8%,对Pu衰变γ射线总能量屏蔽率为93.5%,通过增加Pb层厚度至2mm,可使γ射线总能量屏蔽率达到96.5%。开展了可实现快中子慢化、吸收双功能的含硼石蜡屏蔽材料的制备技术研究,通过冷压制备技术制备了组织致密、加工性能优异的含硼石蜡屏蔽材料,可解决屏蔽材料尺寸受限制以及加工成形困难等难题,可广泛应用于工业辐射防护领域。The design of shielding materials mainly considers the protection requirements against neutrons and γ-rays,and materials with synergistic protection against both neutrons and γ-rays,which can be widely used in many radiation scenarios.In this paper,the types,advantages and disadvantages of shielding materials were introduced,and based on the Monte Carlo N-particle(MCNP)transport code program,the design and optimization of neutron and γ-ray shielding materials were carried out.The design scheme of a novel neutron and γ-ray shielding material with better shielding effect was proposed.The simulation results showed that adding a certain amount of B_(4)C into paraffin wax could significantly improve the shielding efficiency of the material against neutrons.Among them,the boron-containing paraffin with the addition amount of 10wt%~20wt% B_(4)C had an excellent neutron shielding effect.The shielding rate of the designed 75mm boron-containing paraffin(10% B_(4)C)/1mm Pb multilayer shielding materials against Pu spontaneous fission neutrons and Pu decay γ-rays was 96.8% and 93.5%,respectively.The shielding rate against Pu decay γ-rays could reach 96.5% by increasing the thickness of the Pb layer to 2mm.The article carried out research on the preparation technology of boron-containing paraffin shielding materials that could achieve fast neutron moderation and absorption dual functions,and prepared boron-containing paraffin shielding materials with dense structure and excellent processing performance through cold pressing preparation technology,which could solve the problems of size limitation and difficult processing and forming of shielding materials,and could be widely used in industrial radiation protection fields.

关 键 词：屏蔽材料 含硼石蜡 MCNP 冷压技术 屏蔽率 

分 类 号：TL77[核科学技术—辐射防护及环境保护] TL93