Effect of titanium dioxide addition on radiation shielding properties of pumice-iron sand composite mortar

This study investigated the effect of adding ۴%-۲۰% TiO۲ to a pumice-iron sand composite mortar sample in the development of radiation shielding materials. It focuses on the effective atomic number, porosity, attenuation coefficient, protection efficiency, and spectral attenuation behavior based on XCOM and GEANT۴ simulation via ۱۰۸ monoenergetic gamma photons of ۰.۳۵۶ MeV, ۰.۵۱۱ MeV, ۰.۶۶۲ MeV, ۰.۸۳۵ MeV, ۱.۱۱۵ MeV, ۱.۱۷۳ MeV, ۱.۲۷۵ MeV, ۱.۳۳۳ MeV, and ۱.۴۶۱ MeV. The study results show that the TiO۲ enhancement identified at increased titanium content in composite constituent elements caused an increase in the effective atomic number. The lowest porosity was observed at an ۸% TiO۲ addition, as indicated by the photopeak height in the energy spectrum of the absorbed energy. Adding TiO۲ increases the average LAC over ۰% TiO۲ composite mortar samples by ۱.۱%, ۲.۳%, ۳.۸%, ۵.۱%, and ۶.۶% for ۴%, ۸%, ۱۲%, ۱۶%, and ۲۰% TiO۲ addition, respectively. The same trend of the increased LAC is also evident in the GEANT۴ simulation, i.e., ۱.۵%, ۲.۶%, ۵%, ۵.۸%, and ۷.۲%. An increase in TiO۲ levels increases the RPE, while an increase in photon energy decreases the RPE. The trend is in line with the photon energy absorption in the composite sample. On the energy absorption spectrum of the composite, double escape peaks were identified at ۰.۲۵۸ MeV, ۰.۳۱۳ MeV, and ۰.۴۴۰ MeV for ۱.۲۷۵ MeV, ۱.۳۳۳ MeV, and ۱.۴۶۱ MeV energies, respectively. The energy absorption of the composite mortar was strongly dependent on the effective atomic number of the composites.

کلیدواژه ها:

Effective atomic number ، porosity ، Attenuation ، Energy Spectrum ، Monte Carlo simulation