Effect of TiO2 on electrical conductivity, viscosity, and melt structure of electroslag remelting slag

Abstract

Electrical conductivity and viscosity of electroslag being crucial parameters. Using a high-temperature physical property measuring instrument, the effects of different TiO2 concentration and temperatures on electroslag conductivity and viscosity were investigated. With an increase from 1733 K to 1823 K resulting in elevated electrical conductivity (1.04 to 1.89 S · cm−1) and reduced viscosity (0.14 to 0.09 Pa · s). This is because the higher the temperature is, the more the polymer in the slag is depolymerized. Similarly, as TiO2 content increased from 7% to 16%, the electrical conductivity increased (0.24 to 1.14 S · cm−1), and the viscosity decreased (0.33 to 0.11 Pa · s). TiO2 simplified the structure of the melt, and based on the infrared and Raman spectral analysis, it can be seen that Ti4+ replaced Al3+ in the [AlO4]5− structure to form the Ti2O64−structural unit, which depolymerized the structure of the slag system, leading to the reduction of Q4 units and thus greatly reducing the electrical conductivity. The relationship between electrical conductivity, viscosity, and structure was quantified, demonstrating a clear inverse correlation between electrical conductivity and viscosity. The relationships offer insights into predicting electrical conductivity and viscosity based on slag structure.