Desulphurization of Low-Alloy Steel in a Direct Current ESR Furnace

摘要

Eleven small ingots (70-mm diameter, 500-mm long) were produced in an experimental electroslag-refining furnace using electrode negative and electrode positive direct current power modes to enable the extent of desulphurization to be compared. The electrode material was a commercial low alloy steel (En 25) containing about 0.03 wt% sulphur. The average sulphur reduction determined for each ingot was found to increase as the ingress of oxygen to the molten slag was reduced, and extensive desulphurization was achieved with both power modes provided the entry of oxygen to the slag bath was sufficiently restricted. Slightly lower levels of sulphur removal were recorded for the electrode positive power mode, but whether this was due solely to electrochemical reactions or to the asymmetric pattern of heat generation is uncertain. (Author)