Construction of viscosity diagrams for blast-furnace slag of the CaO-SiO2-Al2O3-10%MgO-2%TiO2-0.5%MnO system by the method of simplex lattices

The widespread practical application of titanium- and aluminum-containing ores in the process of smelting cast iron in blast furnaces complicates this process due to variations in the physical properties of the slag system. This study aims to predict the specific behavior of slags in the CaO-SiO2-Al2O3 system with 10% MgO, 2% TiO2, and 0.5% MnO, by evaluating their viscosity and liquidus temperature within a basicity range of (CaO)/(SiO2) = 0.6–1.5 and varying Al2O3 concentrations of 4–16%. The methodology employed involves the simplex lattice method for experimental planning combined with vibration viscosimetry. New findings reveal how basicity and aluminum oxide concentrations impact the physical properties of the slags in the analyzed oxide system. Specifically, slags with basicity values between 0.9 and 1.2 containing 7–11% Al2O3 at temperatures of 1450 °C and above fall into the homogeneous zone, exhibiting a viscosity of 0.6 Pa·s. Conversely, when basicity reaches 1.2–1.5 with Al2O3 content of 4–6%, slags transition to the heterogeneous zone, with viscosity increasing to 6.0 Pa·s.