Ordinary artificial graphite electrodes use petroleum coke and pitch coke as raw materials, and high-power and ultra-high-power electrodes use needle coke as raw materials. They have low ash content, good electrical conductivity, heat resistance and corrosion resistance, and do not melt or deform at high temperatures. Graphite electrodes are mainly used in electric arc steelmaking furnaces, but also in submerged electric furnaces and resistance furnaces. Graphite electrodes for steelmaking account for 70% to 80% of the total amount of graphite electrodes. It can also be used in various crucibles, graphite boats, dishes, hot die casting molds and vacuum electric furnace heating elements.
Electric furnace steelmaking uses graphite electrodes to introduce electric current into the steelmaking furnace. A strong electric current generates arc discharge through gas at the lower end of the electrode, and uses the heat generated by the arc for smelting. According to the capacity of the electric furnace, graphite electrodes with different diameters are used. In order to use the electrodes continuously, the electrodes are connected by threaded joints. Since the cross-section of the joint is smaller than the cross-section of the electrode, the compressive strength of the joint material should be large and the resistivity should be small.