DC Arc furnace improved hearth construction

A DC arc furnace having an electrically conductive hearth adapted to contain a melt, at least one arcing electrode above the hearth and adapted to form a heating arc with the melt when the hearth and electrode are supplied with DC power;

• the hearth having a wear lining directly contacted by the melt and formed by refractory material through which electrical conductors extend from the bottom of the wear lining to its top, layers of electrically conductive bricks under the wear lining and having a top layer electrically connecting with the electrical conductors, and a metal plate under the layers of electrically conductive bricks and adapted to be connected with the DC power, the layers of conductive bricks having a bottom layer in electrical connection with the metal plate;
• wherein the improvement comprises a layer of mixed bricks between the top and bottom layers of the electrically conductive bricks and formed in part by electrically conductive bricks and in part by electrically non-conductive bricks.