Effect of Process Parameters on In-situ Reduction of Chromium Oxide during Electro Slag Crucible Melting of Cu-Cr Alloy

摘要

Copper-chromium alloy has been successfully produced by electroslag melting with in-situ reduction of Cr_2O_3. It is shown that carbon from graphite crucible/electrode plays a significant role in in-situ reduction of chromium oxide during melting of Cu-Cr alloys. Addition of aluminium as a reducing agent is effective when large amounts of Cr_2O_3 (～13mass% or more) is present in the slag. The reduction reaction appears to be controlled by the availability of dissolved Cr_2O_3 in the slag and to some extent by the slag viscosity. Usage of graphite powder as a reducing agent was not successful because of the increase in slag viscosity. The maximum chromium content of Cu-Cr ingots was as high as approximately 2 mass% using the operating parameters available for crucible melting.