An investigation on gamma-ray and neutron attenuation properties of multi-layered Al/B4C composite

Abstract

Nowadays, the concept of multi-layered composite materials is attracting the researchers in terms of enhancing the capabilities of shielding materials as well as extending the scope of utilization towards space sciences and cosmic radiation application. In this study, we report the manufacturing, design, and experimental investigation on newly developed multi-layered Al/B4C shielding composites. Al powder material with a purity of 99% and an average size of 15 & mu;m is used as matrix material. Next, B4C powders with an average size of 9 & mu;m are incor-porated into the matrix as reinforcement material. Accordingly, we manufactured several different multilayer Al-B4C shield samples of 3 cm diameter and 1 cm height through powder metallurgy method. Gamma-ray trans-mission properties are determined using 3 x 3 NaI(Tl) scintillation detector through 60Co and 137Cs point isotropic radioisotopes. Moreover, MCNPX (version 2.7.0) is utilized for deposited energy amount and trans-mission factor calculations for gamma and neutron radiation. Our results showed that geometric configuration plays a crucial role in shielding efficiency of multi-layered materials. Among the manufactured samples, B4C-Al-B4C sample is reported with promising shielding properties against gamma-ray and neutron radiation. A direct relationship between the overall transmission factor values and deposited energy amount (MeV/g) in each sample is also explored for multi-layered composite shields.It was also seen that combination of layers made significantly improvement of radiation shielding properties of materials.