Elasto-mechanical and nuclear shielding characterization of La₂O₃ based boro-silicate glasses for radiological protection

The influence of Lanthanum oxide incorporation on the physical and mechanical properties, as well as nuclear shielding efficacy against ionizing radiation (including X/gamma rays, neutrons, and heavy ions), of six unique glasses designated S1–S6, containing varying amounts of La₂O₃, was examined. The Makishima-Mackenzie model was employed to compute the mechanical characteristics, including Young's modulus (Y), bulk modulus (B), shear modulus (S), longitudinal modulus (L), microhardness (H), and Poisson's ratio of the examined glasses. The incorporation of La₂O₃ improves the physical and mechanical characteristics of the examined glasses. Multiple gamma-ray shielding parameters were evaluated within the photon energy spectrum of 0.015 to 15 MeV, including the mass attenuation coefficient (μ_m), half value layer (HVL), effective atomic number (Z_eff), radiation protection efficiency (RPE), as well as exposure and energy absorption buildup factors (EBF & EABF), which were computed utilizing the MCNP5 code and XCOM program. The computed values obtained using MCNP5 were compared with the available measured μ_m values, demonstrating a strong agreement between the two methods. Among the analyzed glass samples, the S6 glass (45B₂O₃–10SiO₂–10CaO–35La₂O₃) had the highest μ_m, Z_eff, RPE, and K_a, while demonstrating the lowest HVL, EBF, and EABF values. The results indicate that the current glass composition offers complete (100%) x-ray protection and efficient performance for gamma-ray shielding at energies up to 15 MeV, in comparison to other prevalent gamma-ray shielding materials, as well as certain recently examined glasses and polymers. The macroscopic effective removal cross section (Σ_R) of the examined glasses was computed and compared with commonly utilized neutron shielding materials. The S1 sample demonstrated superior performance, while S6 displayed a comparable value relative to graphite, concrete, basalt magnetite, and several recently investigated glasses and alloys. The mass stopping power (MSP) and projected range (PR) values for protons (H⁺¹) and alpha particles (He⁺²) have been evaluated within the energy spectrum of 0.01-15 MeV. The S6 sample was found to exhibit the most effective proton and alpha shielding among the evaluated samples. The results indicate that the analyzed glass samples serve as superior nuclear shielding materials for several applications.