Gamma Radiation Shielding Efficiency of High Entropy Alloys: A Comparative Study

High entropy alloys (HEAs) represent a novel class of materials characterized by their unique composition of four or more principal elements in near-equiatomic ratios, offering exceptional properties for various applications. This study investigates the gamma radiation shielding parameters of selected HEAs, namely FeCoNiCrMn, TaNbHfZrTi, NbMoTaW, AlMoNbV, and NbTaTiV. Mass attenuation coefficients (MAC) were calculated by using EpiXS program over a photon energy range of 0.015-15 MeV and these results were verified using with the WinXCOM software. The results show that the MAC values are highest at low photon energies due to the photoelectric effect, with notable peaks corresponding to the K-shell absorption edges of specific elements. At photon energy of 0.015 MeV, the MAC values for the FeCoNiCrMn, TaNbHfZrTi, NbMoTaW, AlMoNbV, and NbTaTiV alloys are 57.6, 90.4, 98.9, 27.8, and 81.5 cm²/g, respectively. Among these alloys, NbMoTaW exhibits the highest MAC value, whereas AlMoNbV displays the lowest. The half-value layer (HVL) and mean free path (MFP) values were also found thinner for NbMoTaW at all of the photon energies. Additionally, the effective atomic number (Zeff) and exposure buildup factors (EBF) were analyzed. The results demonstrate that NbMoTaW and TaNbHfZrTi, offer superior radiation shielding capabilities compared to conventional shielding materials, with higher usability in environments subjected to gamma radiation. These findings underscore the promise of HEAs in advanced shielding applications, showcasing their ability to enhance safety and performance in sectors with high demands.