Method for removing undesired elements, particularly H.sub.2 and O.sub.2, in electroslag remelting and an arrangement for carrying out the method
AssigneeVereinigte Edelstahlwerke Aktiengesellschaft (VEW)
InventorHeimo Jaeger
Life of this patent
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Abstract
An electroslag remelting or refining method and arrangement for removing undesired elements, particularly H.sub.2 and O.sub.2, from metals. A water-cooled mold having a bottom plate is adapted to being raised in known manner. A growing metal ingot solidifying in the mold has a solidified portion and a liquid metal sump portion. A layer of molten slag covers the liquid metal sump. A self-consuming electrode extends into the slag. An a.c. source is connected between the electrode and bottom plate. Oppositely-poled auxiliary electrodes are included which are in electrical contact with the slag cover, the auxiliary electrodes being connected to opposite polarity terminals of a d.c. source.
Claims12
In an electroslag remelting metho for removing undesired elements from a metal, including the steps of applying an a.c. voltage between at least one self-consuming electrode and a mold containing a growing ingot, melting said self-consuming electrode in a liquidifed, conductive slag and solififying the melt in a liquid-cooled mold, the improvement comprising the steps of:
- applying a voltage of a certain first magnitude to one non-fusing auxiliary electrode and a voltage of a magnitude different from said first magnitude to another non-fusing auxiliary electrode which are in electrical contact with said slag for creating a d.c. current flow in the slag;
- and
- removing the undesired elements by fusion electrolysis, said undesired elements which are present in the slag in the form of ions, migrating to said auxiliary electrodes and said self-consuming electrodes, wherein the undesired elements are removed by chemical reaction with the air, the slag and the material of the auxiliary electrodes.
In an electroslag remelting arrangement for removing undesired elements, of the type including at least one self-consuming electrode, a liquid-cooled mold affixed to a bottom plate, an a.c. source connected between said electrode and bottom plate, a growing metal ingot solidifying in said mold having a solidified portion and a liquid metal sump portion, and a molten slag cover extending over said liquid metal sump, the improvement comprising oppositely poled auxiliary electrodes which are in electrical contact with said slag cover, each of said auxiliary electrodes being connected to respective opposite polarity terminals of a d.c. source for creating a d.c. current in the slag.
Dependencies are inferred from the claim text.