Fabrication and characterization of barium based bioactive glasses in terms of physical, structural, mechanical and radiation shielding properties

Abstract

A novel bioactive glass system 20SiO2- 7.5Na2O- 7.5K2O- (65-x)P2O5- xBaO (where x = 2.5, 5.0, 7.5 and 10.0 mol %) has been fabricated using melt quenching method and corresponding samples named as GB1, GB2, GB3 and GB4, respectively. The formation of glass has been confirmed by X-ray diffraction (XRD) analysis. Physical and structural properties include measurement of density (ρGlass), molar volume (Vm), oxygen packing density (OPD), oxygen molar volume (Vmo), ionic concentration measurement (N), interionic distance (R), Polaron radius (Rp) and Phosphorous molar volume Vmpfor all the selected glass samples. Mechanical properties include packing density (Vt), Young's modulus (Y), bulk modulus (K), shear modulus (S), longitudinal modulus (L), hardness (H) and Poisson's ratio (σ) has been studied using Makishima-Mackenzie and Rocherulle models. Radiation shielding properties viz. mass attenuation coefficient (MAC), effective atomic number (EAN), effective electron number (EEN), half value layer (HVL) and tenth value layer (TVL) have been evaluated theoretically using the WinXCom and PSD software packages for all the glass samples and experimentally verified at selected photon energies of 511 keV (Na22), 662 keV (Cs137), 1173 keV and 1332 keV (Co60) using gamma ray spectroscopy. Additionally, some of these radiation shielding properties for the fabricated glasses were compared with commercially used concretes, radiation shielding glass (RS253 G-18) and registered 45S5 Bioglass®. GB4 glass sample is found to possess all the qualities which are essential for an ideal radiation shielding material and can easily replace commercially used radiation shielding materials.