1. Field of the Invention
The invention relates to steelmaking, particularly to additive compositions for use during steelmaking in electric arc furnaces.
2. Description of the Prior Art
The use of electric arc furnaces in steelmaking is a technique well-known to those skilled in the steelmaking art. Basically, the electric arc process differs from other steelmaking processes in its use of scrap steel as most of the charge. The scrap is added to the furnace at the beginning of the process cycle and melted down by the passage of electric current through the furnace's graphite electrodes, prior to the addition of the other components of the charge. A slag is formed on the surface of the charge during the initial melt-down, which remains during the entire process cycle until tapping of the heat.
Control of the rate of consumption of the graphite electrodes during the course of the process is an important part of electric arc furnace steelmaking. Minimizing electrode oxidation is a factor in controlling electrode consumption, as is maximizing the length of the arc between electrodes. Short electrode arcs give rise to a number of problems, including undesired splattering of the steelmaking charge about the vessel, rapid oxidation of the electrodes, and the inability to attain and/or maintain the high temperatures necessary to convert the charge to steel in the required cycle time.
Avoidance of these problems has been attempted through the use of a variety of methods known to those skilled in the steelmaking arts. None of these known techniques, however, has satisfied the need in electric arc furnace steelmaking to simultaneously reduce charge splattering, minimize electrode oxidation and consumption and maintain the desired high temperatures for time-efficient steelmaking without corroding the refractory of the furnace and/or ladle.
USPTO Backgrounds
USPTO Backgrounds