Structure-based viscosity model development for titania aluminosilicate slags

ABSTRACT

Based on the structure of melts, a model has been developed that estimates the viscosity of the fully liquid melts in the CaO–MgO–Al₂O₃–SiO₂–TiO₂ systems. Three kinds of tetrahedral ([SiO₄]⁴⁻, [AlO₄]⁵⁻, and [TiO₄]⁴⁻) are considered in the titania aluminosilicate slag. According to the hole theory of melts, this model provides a link between the viscosity and the structures of the melts. The present model is capable of predicting the viscosities in the CaO–MgO-–Al₂O₃–SiO₂–TiO₂ systems with wide composition and temperature ranges above liquidus; the average of relative errors for this model was approximately 20.0%. From the model calculation results, the addition of TiO₂ decrease the viscosity of slag under non-reducing atmosphere. The ability of increasing viscosity follows the order: SiO₂> Al₂O₃> TiO₂> CaO. Due to the charge compensation and unit size effect, the replacement of TiO₂ by Al₂O₃ will result in the increase of viscosity.

KEYWORDS:

• Titania melts
• viscosity modelling
• melt structure

Acknowledgement

The authors are pleased to acknowledge the financial support provided by ACIPCO for this research project. We also thank Department of Metallurgical and Materials Engineering, The University of Alabama for providing the experimental and analytical facilities for this research work.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This study was supported by Program for the Youth Top-notch Talents of Chongqing (grant number 20151001) and the China Scholarship Council.