Relationship between melting-conditions and gamma shielding performance of fluoro-sulfo-phosphate (FPS) glass systems: A comparative investigation

To assess the relationship between gamma ray shielding performance and glass-melting conditions, an extensive investigation was performed on different types of fluoro-sulfo-phosphate (FPS) glasses. Four different FPS glasses melted in Al and Pt crucibles were modeled in MCNPX (version 2.6.0) general purpose Monte Carlo code. For this aim, a gamma-ray transmission setup has been modeled with essential simulation equipment. The mass attenuation coefficients for each glass sample in different melting-condition were determined. The obtained mass attenuation coefficients were utilized for determination of Half Value Layers (HVL) and mean free paths (mfp). Next, energy absorption buildup factors (EABF) and exposure buildup factors (EBF) of investigated FPS glasses were determined by using geometric-progression (G-P) fitting method. To evaluate the effect of glass-melting conditions on fast neutrons, effective removal cross sections of FPS glasses were calculated. Finally, an extensive comparison between the superior samples of FPS glasses melted in Al and Pt crucibles were performed. The results showed that GPT-4 sample melted in Pt crucible has relatively higher radiation shielding properties than GAL-2 sample which melted in Al crucible. In addition to material additive, the results showed that even glass-melting conditions has a significant impact on radiation shielding properties of glass material. It can be concluded that, in addition to the most effective material additives into glass structures to improve radiation shielding performances, providing them in the most favorable melting-conditions can provide a versatile improvement.