عنوان مقاله [English]
نویسندگان [English]چکیده [English]
It is time-consuming and costly to build geometric shapes of neutron shields using machining techniques. In addition, in the case of large shields or the need for quick construction, common polymer shields such as boron-containing polyethylene are not efficient. In this study, Poly Methyl Methacrylate (PMMA) as a polymer base, boric acid powder as a neutron absorber and high-density polyethylene powder for increasing the amount of hydrogen have been used to build composite shielding by in situ polymerization method. The percentage of optimal composition of composite materials was calculated using simulation in the MCNPX code and the made shields in the layout including the 3He detector and the Am-Be neutron source were evaluated. Based on the results, the thermal neutron flux is decreased about 80% after composite shielding containing 67% PMMA, 28% Boric Acid and 5% High Density Polyethylene (HDPE) compared to the pure polyethylene shielding. The results showed a good performance of this composite shield.