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AssigneeIowa State University Research Foundation, Inc.
InventorsFrederick A. Schmidt, David T. Peterson, John T. Wheelock, Lawrence L. Jones
Estimating the term…
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 prefused, 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.
A method of treating rare earth-transition metal scrap contaminated with a non-metallic or metallic impurity for reuse in the manufacture of end-use articles, comprising the steps of:
A method of treating rare earth-iron alloy scrap contaminated with oxygen and nitrogen impurities for reuse in the manufacture of end-use articles, comprising the steps of:
A method of treating rare earth-transition metal scrap contaminated with oxygen and nitrogen impurities for reuse in the manufacture of end-use articles, comprising the steps of:
Dependencies are inferred from the claim text.