In this study, 6061-aluminum metal matrix composites doped with varying concentrations of ytterbium(III) oxide were synthesized using high-energy mechanical alloying to evaluate their structural, physical, and radiation shielding properties. X-ray diffraction confirmed the retention of the aluminum crystal structure with no secondary phase formation, while scanning electron microscopy and energy-dispersive X-ray spectroscopy revealed homogenous dispersion of Yb2O3 particles within the matrix. With increasing Yb2O3 content, particle densification and structural integrity were significantly enhanced. Gamma-ray and neutron shielding performance was assessed through theoretical modeling and Monte Carlo simulations.

At low photon energy, the 20 wt% Yb2O3 composites showed a remarkable increase in linear attenuation coefficients compared to the undoped 6061-aluminum matrix. Neutron removal efficiency also increased by 32% at the highest Yb2O3 content. It can be concluded that Yb2O3 incorporation significantly improves both the photon and neutron shielding performance of the 6061-aluminum metal matrix.