不同材料的中子透射Monte Carlo模拟计算  

Monte Carlo simulation of neutron transmission through various materials

作　　者：曾心苗[1,2] 周鹏[1,2] 秦培中[1,2] 鲍矛[1,2] 郭广水[1,2] 许自炎[1,2] 

机构地区：[1]北京市射线应用研究中心 [2]北京市科学技术研究院辐射新材料重点实验室,北京100012

出　　处：《核技术》2011年第3期188-192,共5页Nuclear Techniques

摘　　要：用Monte Carlo粒子输运计算程序(M-C程序)对入射能量从0.025eV到20MeV的中子及入射厚度1–40cm的多种材料进行了中子透射性能计算。这些屏蔽材料有主体材料聚乙烯、水和混凝土、铁、铜,铅和聚乙烯-碳化硼复合材料,以及功能添加剂碳化硼和氧化钆。结果显示,随着材料厚度的增加,中子透射系数降低;同一种材料,随入射中子能量的降低透射系数降低的幅度呈增大趋势,但聚乙烯和水的透射系数较小且下降幅度与能量低于0.1MeV的中子基本相同,有些材料随厚度增加出现能量较高中子的透射系数低于能量较低中子透射系数的现象;不同材料的中子透射系数随厚度增加而降低的幅度在能量较低时差别明显,能量高时差别减小。主体材料与功能添加剂组合有利于提高材料的屏蔽能力。In this paper, the MCNP code is used to calculate neutron transmission through various materials of 1-40 cm thickness in energy range of 0.025 eV to 20 MeV. The materials are principal shielding materials of PE, water, concrete, Fe, Cu, Pb and PE/BC4composite, and the additives of B4C and Gd2O3. The following results were obtained： （1） the neutron transmission decreased with increasing thicknesses of a material; （2） for a certain material, with decreasing energy of the neutrons, the neutron transmission decreased faster, except PE and water, where the neutron transmision keeps almost the same in the entire energy range; and （3） for low energy neutrons, the differences of transmission decreasing trend with the increasing thicknesses for different materials were significant, whereas for high energy neutron, the decreasing trend was not distinct. A combination of a main material with an additives can achieve better shielding effect.

关 键 词：中子 透射系数 MONTE CARLO方法 屏蔽材料 功能添加剂 

分 类 号：O571.53[理学—粒子物理与原子核物理]