Abstract The fast and thermal neutron attenuation properties through polymer composites based on high density polyethylene (HDPE) reinforced by micro-sized and nano-sized Cadmium Oxide (CdO) particles with weight fractions of 10% and 40% have been investigated. This study was carried out to present a new composite material based on HDPE filled with CdO in the form of micro and nano particles to be used as a promising neutron radiation shielding material. The composites were fabricated by compression molding technique and characterized by a scanning electron microscope (SEM). The composites were subjected to fast neutrons generated from 238Pu–Be neutron source with activity 12 × 109 Bq and detected by a Stilbene scintillator. The fast neutron shielding properties were determined in terms of the fast neutron transmission fractions of the composites. The neutron activation method was applied by using Indium foils and Indium foils covered with Cadmium as a detector to study the properties of the thermal and epithermal neutron fluxes of the composites upon exposure to neutron flux generated from 241Am–Be neutron source. It is clear from this study that the transmitted fractions for fast neutron in case of nano CdO/HDPE composites are less than the case of micro CdO/HDPE composites, however, the capture of thermal neutrons inside the micro CdO/HDPE composites is more probable than that in nano CdO/HDPE composites at the same weight fraction. Tensile mechanical testing has been conducted and showed that particle addition percentage and size have significant effect on the mechanical properties of composites. Nano CdO/HDPE composites showed more superior mechanical properties compared to micro CdO/HPDE composites at the same particle addition level.

中文翻译：

---

通过微米级和纳米级 CdO 增强 HDPE 复合材料实现快速和热中子衰减

摘要 研究了基于高密度聚乙烯 (HDPE) 的聚合物复合材料的快速和热中子衰减特性，该复合材料由重量分数为 10% 和 40% 的微米级和纳米级氧化镉 (CdO) 颗粒增强。本研究旨在提出一种基于 HDPE 的新型复合材料，其中填充有微米和纳米颗粒形式的 CdO，可用作一种有前景的中子辐射屏蔽材料。复合材料通过压缩成型技术制造，并通过扫描电子显微镜（SEM）进行表征。复合材料受到由 238Pu-Be 中子源产生的快中子的影响，其活度为 12 × 109 Bq，并由二苯乙烯闪烁体检测。根据复合材料的快中子传输分数确定快中子屏蔽性能。中子活化方法通过使用铟箔和覆盖有镉的铟箔作为探测器来研究复合材料在暴露于 241Am-Be 中子源产生的中子通量时的热和超热中子通量的性质。从这项研究中可以清楚地看出，在纳米 CdO/HDPE 复合材料的情况下，快中子的传输分数小于微 CdO/HDPE 复合材料的情况，但是，在微 CdO/HDPE 复合材料内部捕获热中子的可能性更大与相同重量分数的纳米 CdO/HDPE 复合材料相比。拉伸力学测试表明，颗粒添加百分比和尺寸对复合材料的力学性能有显着影响。