Impact of B4C reinforcement on the microstructure, wear, hardness, corrosion behavior, and radiation shielding properties of Al-40Sm2O3 hybrid composites

This study investigates the production and properties of hybrid Al-based composites reinforced with Sm2O3 and B4C. Al-40Sm2O3 powders were milled using vibratory grinding, and B4C was added in varying ratios of 1, 5, 9, 13, and 15 wt%. X-ray diffraction (XRD) analysis confirmed the presence of Al, Sm2O3, and B4C phases and revealed significant changes in phase distribution with increasing B4C content. SEM-EDX analysis demonstrated consistency between the initial compositions and the resulting composite structure, with improved microstructural homogeneity as the B4C content increased. The inclusion of B4C significantly enhanced the wear resistance, corrosion resistance, and hardness of the composites. Although a slight reduction in relative density was observed due to the low density of B4C and interfacial bonding challenges associated with Al6061/B4C systems, the Sm2O3 reinforcement effectively mitigated these issues by acting as a binding agent. Additionally, B4C reinforcement improved the composite's mechanical and physical properties. Radiation shielding analyses, conducted using MCNP6.2 simulation, revealed increased thermal neutron macroscopic cross-sections with higher B4C content, while gamma-ray attenuation properties decreased with reduced Al/Sm2O3 ratios. These findings highlight that while B4C reinforcement enhances mechanical properties and thermal neutron shielding, its photon attenuation properties require optimization. This study provides critical insights for designing hybrid composites for advanced radiation shielding applications.