Experimental investigation of lead free Nano-composite shield based on epoxy resin for Cobalt-60 gamma-ray source

Radiation protection against gamma-ray sources is very essential due to its damaging effect on living tissues. For this purpose, Lead and concrete are known as common materials for gamma-ray shielding applications. In compact and low space environment, lead is the first choice. But lead shields have some drawbacks. Therefore, efforts to replace the conventional lead-based shields caused the introduce some novel shielding materials. In this study, a lead-free composite shield based on epoxy resin, reinforced with a low concentration (5 wt%) of WO3 nanoparticles was fabricated at different thicknesses. Then, the gamma-ray attenuation capability of the WO3/Epoxy Nano-composite was compared to the PbO/Epoxy Micro-composite utilizing a high-energy gamma-ray source (Cobalt-60). The study indicates that at the same filler concentration, the nano-sized WO3 composite could achieve better gamma-ray shielding performance, at all shield thicknesses. However, this advantage become less apparent at higher shield thicknesses. Furthermore, the data show that the manufactured Nano-composite shield could be an appropriate alternative to ordinary concrete. From a gamma ray (instead of a mixed gamma-neutron) radiation shielding perspective, using a nano-sized WO3 composite rather than a PbO/Epoxy Micro-composite does not provide considerable shielding efficiency, at least at high gamma radiation energy.