Density and Electrical Conductivity of Synthetic Slags Added to the Ladle-Furnace Unit

摘要

The properties of a series of synthetic slag melts for steel refining in the ladle-furnace unit are determined in the range 1430-1645°C: the slag density p on the basis of the maximum pressure in a gas (argon) bubble; and the electrical conductivity a; by the double-contact ac volt-ampere method (at 2 and 5 kHz). On the basis of the measurements, the following characteristics are calculated: the bulk expansion coefficient β and actual molar volume V_M (both referred to 1600°C), the relative excess molar volume δV_M, the activation energy E_? of the electrical conductivity, and the preexponential factor a; in the Arrhenius equation that approximates the influence of the temperature on as. The dependence of these variables on the degree of replacement N of the polymer-forming oxides Al_2O_3 and SiO_2 in the slag batch by sodium monoxide is analyzed. With increase in N, it is found that ρ, δV_M, E_?, and ?_0 decline monotonicaily, while ? increases. The dependence of β on N is more complex. The behavior of β and δV_M is discussed in terms of the polymer theory of slags.