Cationic Effect on Electrical Conductivity and Viscosity of Alkaline-Earth Silicate Melts: Phenomenology

Electrical conductivity and viscosity are measured in CaO-MgO-SiO₂ and CaO-BaO-SiO₂ melts to address the cationic effect on electrostatic interaction and strain field distortion based on the Anderson-Stuart theory. Electrical conductivity and viscosity at 1873 K are measured by two-plate method and rotating cylindrical method, respectively. The effect of cationic radius on electrostatic energy and strain field distortion energy is distinguished by comparing the results of polymerized(NBO/T = 0) and depolymerized(NBO/T = 2.0) melts. The antithetic effects of cationic radius on two activation energies are shown in this work. In depolymerized silicate melts, it is proven that electrostatic energy is dominant over the strain field distortion energy and thus the electrical conductivity increases and viscosity decreases with increasing cationic radius. The absence of electrostatic interactions in polymerized compositions is again confirmed by correlating two properties through the Walden plot.