Effect of CaF2 on the radiation attenuation properties of SiO2–P2O5–CaO–Na2O bioactive glasses: Theoretical and simulation studies

Abstract

In this study, the gamma-photon, neutron, and charged particle interaction quantities for SiO2–P2O5–CaO–Na2O–CaF2 bioactive glasses were evaluated with the objective of estimating the effect of CaF2 on the physical and radiation responses of the bioactive glasses involved. The physical features (e.g. glass density) were increased as the CaF2 increases in the samples. The gamma mass-attenuation coefficient (μ/ρ) of the glasses was estimated for photon energies 0.015–15 MeV using the XCOM database and the FLUKA Monte Carlo simulation procedure. The total stopping powers (TSP) and range of charged particles (electrons, protons, α-particles, and C6+ ions) were estimated with the aid of ESTAR (for electrons only) and the SRIM Monte Carlo code (for protons, α-particles, and C6 + ions). In addition, the fast (ΣR) and thermal (TN) neutron cross-sections were computed for the glasses using standard theoretical models. The μ/ρ values of the SPCNCF glasses were within 0.0216–8.7469, 0.0217–9.2151, 0.0219–10.0588 and 0.0222–11.1264 cm2/g for SPCNCF1, SPCNCF2, SPCNCF3 and SPCNCF4, respectively. The half-value layers had minimum values of 0.02936, 0.02767, 0.02499, and 0.02215 cm for SPCNCF1, SPCNCF2, SPCNCF3, and SPCNCF4, respectively, at 0.015 MeV. Analysis of the estimated photon interaction parameters showed that the gamma radiation attenuation prowess of the glasses improved with CaF2 content. The same trend was observed for charged particles. The TSP of electrons is maximum at 0.015 MeV with values of 12.82 for SPCNCF1 and SPCNCF2, 12.76 for SPCNCF3 and 12.71 MeV cm2/g for SPCNCF4. The values of ΣR were equal to 0.0896, 0.0896, 0.0897 and 0.0900 for SPCNCF1, SPCNCF2, SPCNCF3, and SPCNCF4, respectively. The increase in the weight proportion of CaF2 also improved the fast neutron removal and total thermal neutron interaction capacities of the SPCNCF glasses. The SPCNCF glasses showed better shielding competence compared to some conventional shields such as RS 253 and RS 253 G18 commercial shielding glasses, concrete samples, and polymers.