Comparative neutron-shielding properties of metal oxide/HDPE composites using a Monte Carlo Code of PHITS

Abstract

Development of efficient neutron-shielding materials has become one of the most important issues in radiation safety. In order to estimate shielding performances of the materials of interest, simulations of neutron-shielding characteristics using well-proved methods are necessary. In this work, a Monte Carlo code of Particle and Heavy Ion Transport code System (PHITS) was used to simulate neutron-shielding properties of HDPE composites that were added with either B2O3, Sm2O3, Gd2O3, or CdO as a filler at various contents. The energy of the incoming neutrons was fixed at 0.025 eV with the beam direction pointing at the right angle to the material's surface. The results showed that Gd2O3/HDPE composites had the lowest neutron transmission ratio compared with other fillers at the same contents, implying the highest neutron-shielding ability. Furthermore, the simulations also showed that the values of neutron transmission ratios of all fillers decreased with increasing filler's contents. Other information such as half-value-layer (HVL) and tenth-value-layer (TVL) were also simulated and reported in this work. We encouraged further investigation of this work by comparing the simulated results with the actual experiment in order to validate the accuracy of the simulation.