Calculation of activation energy of viscosity for evaluation of metallurgical slag melts structure

Measurements of metallurgical slag viscosity were performed. The studied slags have been found to have close viscosity (η) values over a wide temperature range from 1453 to 1873 K. The results demonstrate that the viscosity decreases with the increase of CaO/SiO2 ratio. Temperature inflection points (T’) are found in the η = f(T) dependence, and they are consistent with the chemical composition of slags below 1453 K. The value of T’ increases with the increase of CaO/SiO2 ratio. The activation energy of viscosity Eη was calculated by using the Frenkel equation. With the increase of temperature, Eη decreases and does not depend on the chemical composition of slags. In the temperature region from 1473 to 1573 K, the temperature dependence of Eη = f(T) demonstrates energy deviations from the trend line indicating the relaxation of structurally sensitive bonds. The results obtained are of practical importance for the selection of rational slags for different metallurgical processes.