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High-density polyethylene (HDPE) has been reinforced with various ratios of iron oxide (-Fe2O3) and aluminum (Al) nanoparticles (NPs) to be used as shielding materials against nuclear radiation. The examination of scanning electron microscopy images (SEM) reveals small polymeric agglomerations besides the uniform dispersion of Al and -Fe2O3 NPs. Also, all stress parameters (i.e σ_Y,σ_M,and σ_f) decremented after incorporating the 40 wt.% -Fe2O3 NPs into the HDPE matrix. Meanwhile, the mutual additions of Al powder with -Fe2O3 NPs in samples P2 (30% -Fe2O3/10% Al) and P3 (20% -Fe2O3/20% Al) led to improving the tensile parameters. These results may be due to the physical reactions between -Fe2O3 NPs and Al powder and polymeric chains. Generally, the polymeric materials are characterized as low-cost and lightweight compared to standard shielding materials. The fast neutrons and gamma-rays shielding properties of the prepared samples were experimentally measured using a shielded 239Pu-Be source and stilbene detector. The neutron removal cross-section (Ʃ_R) and gamma-ray liner attenuation coefficient (μ), in addition to the mean free path (MFP) and the half-value layer (HVL) for the prepared samples, have been calculated. The results showed that the nanocomposite containing 40% iron oxide had improved the neutron and gamma-ray shielding properties compared to the pure HDPE and other prepared nanocomposites. The values of MFP and HVL indicate that the prepared nanocomposites can be used for shielding gamma-rays and neutrons from radioactive isotopes and from other nuclear radiation facilities compared to common shielding materials such as concrete.

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In this work, different ratios of iron oxide (-Fe2O3) and aluminum metal (Al) nanoparticles in powder shape have been used to prepare HDPE nanocomposites for -rays shielding applications. The electrical and magnetic properties of prepared samples were investigated. The WinXCom and MCNP5 programs have been used to calculate the mass attenuation coefficients (μ/ρ) of γ-rays for the prepared samples. The μ/ρ for the prepared samples have been measured experimentally via a narrow beam of γ-rays at energies of 662, 1173, and 1332 keV from 131Cs and 60Co radioactive sources. The impact of -Fe2O3 and Al on the γ-ray shielding ability of prepared composites have been clarified. The exposure buildup factor (EBF) has been calculated at energies of 0.015, 0.1, 1, and 10 MeV using MCNP5 program. The results indicated that the fillers affected the EBF at photon energies less than 0.1 MeV. HDPE as a polymeric matrix shows very stability with non-polar features against temperature and frequency. However, the prepared nanocomposites show a remarkable enhancement of their dielectric and electrical properties. Furthermore, the magnetic measurements depict unsaturated weak ferromagnetic behavior for -Fe2O3 nanocomposites, and diamagnetic characteristics for HDPE and Al. The HDPE-based nanocomposites showed improved electrical and magnetic properties along with improved ability to attenuate low-energy γ-rays compared to pure HDPE.

In this work, the shielding performance of (97.3–x)Pb–xCd–2.7Ag (x = 10, 18, and 30) ternary alloys against neutrons and gamma rays has been investigated. The microstructure, thermal and mechanical properties of the ternary alloys were examined. The total mass attenuation coefficients, μ / ρ , for prepared alloys were determined at 662, 1173, and 1332 keV photon energies using NaI (Tl) scintillation detector. The theoretical values of μ / ρ were calculated using WinXCom program depending on the mixture rule. The estimated values were compared with the measured values for all investigated alloys. Atomic cross-section, σ a, electronic cross-section, σ e, effective atomic number, Z eff , effective electron number, N eff , and GP fitting parameters (b, c, a, Xk, and d) were determined. The exposure buildup factor, EBF, have been also calculated. Fast neutron attenuation for the prepared samples have been investigated via the macroscopic effective removal cross-section ( ∑ R ) calculation. Also, thermal neutron attenuation has been evaluated via neutron scattering calculator. The results show that the alloys containing 10 and 30% Cd compromise between superior tensile strength and Young modulus, while the pasty range, heat of fusion and ductility decreased with increasing Cd content. Moreover, the prepared ternary alloys have a high attenuation ability for gamma rays as the standard Pb. The increase of Cd ratio also significantly enhances the thermal neutron attenuation by amazing way along with the increase in the attenuation rate of fast neutrons.