Evaluation of gamma-ray exposure buildup factors and neutron shielding for bismuth borosilicate glasses

• We reported gamma and neutron shielding of bismuth borosilicate glasses.
• We found borosilicate glass with 20 mol% Bi2O3 a superior shielding.
• We report that Bi2O3 containing glasses are most promising shielding materials.
• Buildup factors of glasses were compared with steel–magnetite concrete and lead.

Gamma-ray exposure buildup factor (EBF) values and neutron shielding effectiveness of bismuth borosilicate (BBS) glass systems in composition (50−x)SiO2:15B2O3:2Al2O3:10CaO:23Na2O:xBi2O3 (where x=0, 5, 10, 15 and 20 mol%) were calculated. The EBF values were computed for photon energy 0.015–15 MeV up to penetration depths of 40 mfp (mean free path) by the geometrical progression (G-P) method. The EBF values were found dependent upon incident photon energy, penetration and bismuth molar concentration. In low- and high-energy photon regions, the EBF values were minimum whereas maximum in the intermediate-energy region. The fast neutron removal cross sections for energy 2–12 MeV were calculated by the partial density method. The BBS glass with 20 mol% Bi2O3 is found to be superior gamma-ray and neutron transparent shielding. The EBF values of the BBS glasses were compared with steel–magnetite concrete and lead. The investigation was carried out to explore the advantages of the BBS glasses in different radiation shielding applications.