Method for treating rare earth-transition metal scrap

Patent · Mon Dec 28 23:00:00 EST 1992

OSTI ID:7205646

Schmidt, F A; Peterson, D T; Wheelock, J T; Jones, L L

Rare earth-transition metal (e.g., iron) scrap (e.g., Nd-Fe-B scrap) is flux (slag) remelted to reduce tramp non-metallic impurities, such as oxygen and nitrogen, and metallic impurities, such as Li, Na, Al, etc., picked up by the scrap from previous fabrication operations. The tramp impurities are reduced to concentrations acceptable for reuse of the treated alloy in the manufacture of end-use articles, such as permanent magnets. The scrap is electroslag or inductoslag melted using a rare earth fluoride-bearing flux of CaF[sub 2], CaCl[sub 2] or mixtures thereof or the slag resulting from practice of the thermite reduction process to make a rare earth-iron alloy. 3 figs.

• DOE Contract Number: W-7405-ENG-82
• Assignee: Iowa State Univ. Research Foundation, Inc., Ames, IA (United States)
• Patent Number(s): US 5174811; A
• Application Number: PPN: US 7-591040
• OSTI ID: 7205646
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
320305* -- Energy Conservation
Consumption
& Utilization-- Industrial & Agricultural Processes-- Industrial Waste Management
ALLOYS
ELEMENTS
IRON ALLOYS
IRON BASE ALLOYS
MANAGEMENT
MATERIALS RECOVERY
MELTING
METALS
PHASE TRANSFORMATIONS
PROCESSING
RARE EARTH ALLOYS
RECYCLING
SCRAP
SCRAP METALS
SOLID WASTES
WASTE MANAGEMENT
WASTE PROCESSING
WASTES