Leaded brass alloys for gamma-ray shielding applications

The leaded brasses show high machinability and atmospheric corrosion resistance. Hence, they are being used in different applications such as machine parts, valves, fittings etc. Besides, they can serve as radiation shields as they contain lead and their radiation shielding properties were not investigated so far. Thus, the aim of this study is to determine the radiation shielding properties of leaded brasses. Standard (CuZn) and leaded (CuZnPb) brasses were prepared and their mass attenuation coefficients (μ/ρ), half-value layers (HVL), tenth-value layers (TVL), mean free paths (MFP) and effective atomic numbers (Z eff ) were determined. Linear attenuation coefficients (μ) of the alloys were measured first at 53, 276, 302, 356 and 383 keV using a HPGe detector and a 133 Ba radioactive source. These values were then used to obtain other parameters. A good agreement was observed between experimental and theoretical results for HVL, TVL and MFP (Dif. ≤ 9%). Photon buildup through the present materials was studied in terms of exposure buildup factor (EBF). Results were presented and discussed regarding the photon energy and penetration depths. Fast neutron removal cross sections were also calculated for the given alloys. Some alloys were also evaluated morphologically by using EDX mapping. The leaded brasses were compared with standard shielding concretes and superior shielding properties against gammas and fast neutrons were obtained when compared with concretes.