2019 Volume 59 Issue 3 Pages 427-431
Electrical conductivity is one of the most important thermophysical properties of oxide melts. In the present study, the electrical conductivities of CaO–SiO2–MgO–Al2O3 type high aluminum blast furnace slags were measured by using four electrode method. It can be concluded that the electrical conductivity decreases as increasing the content of Al2O3, because Al3+ has a strong preference to form AlO45+ tetrahedron and incorporates into the network of SiO44+ which enhances the degree of polymerization of melts. As adding MgO to the slags, the electrical conductivity also decreases due to the stronger polarization ability and thus weaker diffusion ability of small Mg2+ ion relative to Ca2+ ion. However, the electrical conductivity increases with gradually increasing the CaO/SiO2 ratio, owing to the increase of concentration of Ca2+ ion which acts as the charge carrier and the decreases of degree of polymerization.