Elestroslag Remelting of Metals and Alloys under Fluxes with Active Additions in Furnaces of Chamber Type (ChESR)

Abstract

Investigations for finding of additional refining possibilities of ESR are fulfilled in Donetsk National Technical University (DonNTU) and directed for detail investigation of refining possibilities of ESR in the controlled atmosphere in chamber furnace (ChESR) under the calcium-containing fluxes. Theoretical basis of chamber electroslag remelting, investigation of its main mechanisms, creation and realization of technology of producing of commercial ingots from different metals and alloys were developed. Physical-chemical and electrical parameters of ChESR under fluxes of CaF2–Ca system have been investigated. These works have shown the possibility of high-quality ingots production from metals with high reaction ability: chromium, titanium, rare earth elements and their alloys. In particular, the technology of high-quality titanium ingots producing with impurities concentration on the level: oxygen: 0.03-0.06 % wt, nitrogen: 0.005-0.006 % wt, hydrogen: 0.003-0.005 % wt, carbon: 0.01 % wt by the one-step ESR in chamber furnace with consumable electrodes from pressed titanium sponge of TG-90 and TG-100 were obtained. In cooperation with General Electric (USA) the technology of titanium and alloys on its base refining from nitrogen-rich inclusions during the ESR under the calcium containing slag have been developed. It provides the inclusion refining with velocity 0.7–1.1 mm/s