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New Model and Database for Predicting the Viscosity of Molten Slags


Viscosity is one of the thermophysical properties that affect the fluid flow of slags, which impacts the kinetics of processes in both industrial and geological processes. However, viscosity measurements are difficult and, as a result, the quality of the experimental data does not meet the technological demands. Furthermore, experimental viscosity data is only available for a limited range of compositions and temperatures. It has, therefore, been found favorable to model the slag viscosity to make predictions over a wider range of temperatures and compositions.

In the recent article, Accurate Viscosity Prediction for Molten Slags: A New Model and Database, written by several Thermo-Calc Software employees, a new structurally-based viscosity model is presented and database for accurately predicting the viscosity of multicomponent molten slags in the whole composition and large temperatures are presented.

New Model Available in Thermo-Calc and TCOX Database

The new viscosity model is now implemented in the Thermo-Calc software package and, as explained by the authors of the paper, “is applied in conjunction with the existing thermodynamic database for oxides to assess viscosity model parameters for the FeOx–CaO–MgO–Al2O3–SiO2–CaF2–CrOx–Na2O–
MnOx–TiO2–ZrO2–P2O5–Gd2O3–La2O3–V2O5–NiO–CuOx system.” These model parameters are available in the TCOX database for metal slag and oxides, version 10 and newer.

With the new model and database, reliable calculations of the slag viscosity are possible, not only for selected model systems but also many multicomponent industrial and geological applications.

“Accurate Viscosity Prediction for Molten Slags: A New Model and Database” written by Rui Zhang, Samuel Hallström, Huahai Mao, Lina Kjellqvist, and Qing Chen and was published in “ISIJ International” in May 2021.

Thermo-Calc Applications to Slags

Thermo-Calc can be used to predict thermophysical and phase-based properties of slags and slag-metal equilibria for steel and non-ferrous metals processing. Learn more about applications of Thermo-Calc to slags at our Slags page.

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