Electrical Conductivities of High Aluminum Blast Furnace Slags

抄録

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.