Investigation of Gamma Shielding Characteristics of Al2O3/NbC Composites via Experimental Measurements and Phy-X/PSD Analysis

This study explores the gamma radiation shielding performance of alumina (Al2O3)-based composites reinforced with varying weight fractions of niobium carbide (NbC). The evaluation was conducted through a combination of experimental measurements and theoretical simulations. Key radiation shielding parameters—including the linear attenuation coefficient (LAC), half value layer (HVL), tenth value layer (TVL), mean free path (MFP), and radiation protection efficiency (RPE)—were experimentally determined at photon energies of 0.662, 1.173, and 1.332 MeV using a gamma spectroscopy system. It was observed that the experimentally determined LAC values increased as the NbC ratio in the composite increased. The LAC values varied between 0.269 and 0.392 cm-1 for 0.662 MeV, 0.223 and 0.271 cm-1 for 1.173 MeV and 0.189 and 0.250 cm-1 for 1.332 MeV. The MFP, HVL and TVL parameters, which changed inversely proportional to the LAC values, decreased with increasing NbC ratio. In addition to the experimentally found parameters, theoretical calculations of the effective atomic number (Zeff), effective electron density (Neff) and exposure accumulation factor (EBF) parameters were made in the wide energy range between 0.015 and 15 MeV using the Phy-X/PSD software. The comparison between experimental and theoretical results revealed a high degree of consistency, validating the reliability of the computational model. Furthermore, the incorporation of NbC was found to significantly improve the gamma attenuation properties of the alumina matrix, primarily due to enhancements in density and atomic interaction probability. These findings highlight the potential of NbC-reinforced alumina composites for use in advanced radiation shielding applications, particularly in environments requiring lightweight and high-performance protective materials.