Several melting and casting techniques which have been successfully used for purifying refractory metals were evaluated as methods of upgrading automotive scrap steel. These methods include (1) non-consumable electrode arc melt¬ing, (2) electron beam melting, (3) vacuum arc melting, (4) vacuum induction melting and (5) electroslag remelting. The removal of copper, chromium and tin from the scrap was of primary interest since these impurity elements are not removed during the steelmaking process but are known to adversely effect the mechanical properties of steel. The optimum con¬ditions for impurity removal by the above melting techniques were determined using simulated auto scrap in small scale melting experiments. Once these conditions were established they were used to melt actual auto scrap obtained from a commercial source. Evaluation of the processed material was made by chemical analysis, metallographic examination and mechanical property measurements.nElectron beam and vacuum induction melting were found to be effective in removing copper and tin from auto scrap but chromium could only be removed when carbon concentrations were low. A procedure was also developed whereby a high grade stainless steel could be prepared during a single vacuum induction heating step. Chromium, tin and aluminum were suc-cessfully removed from auto scrap using the electroslag remelting method. A suitable extractant for copper was not found however. A separate study was made in which the effect of various concentrations of copper, chromium, nickel and tin on the mechanical properties of mild steel was determined.
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