Loading patent…
AssigneeIowa State University Research Foundation, Inc.
InventorsR. William McCallum, Timothy W. Ellis, Kevin W. Dennis, Robert J. Hofer, Daniel J. Branagan
Estimating the term…
A method of making a rare earth compound, such as a earth-transition metal permanent magnet compound, without the need for producing rare earth metal as a process step, comprises carbothermically reacting a rare earth oxide to form a rare earth carbide and heating the rare earth carbide, a compound-forming reactant (e.g. a transition metal and optional boron), and a carbide-forming element (e.g. a refractory metal) that forms a carbide that is more thermodynamically favorable than the rare earth carbide whereby the rare earth compound (e.g. Nd.sub.2 Fe.sub.14 B or LaNi.sub.5) and a carbide of the carbide-forming element are formed.
A method of making a rare earth compound, comprising reacting a rare earth carbide, a compound-forming element, and a carbide-forming element that forms a carbide more thermodynamically favorable than said rare earth carbide, so as to form the rare earth compound and a carbide of said carbide-forming element as a separate carbide phase in said compound.
A method of making a rare earth-transition metal compound, comprising carbothermically reacting a rare earth oxide to form a rare earth carbide and heating the rare earth carbide, a compound-forming element, and a carbide-forming element that forms a carbide more thermodynamically favorable than said rare earth carbide so as to form the rare earth-transition metal compound and a carbide of said carbide-forming element as a separate carbide phase in said compound.
A method of making a rare earth-transition metal-boron compound, comprising carbothermically reacting a rare earth oxide to form a rare earth carbide and heating the rare earth carbide in the presence of reactants comprising a transition metal, boron, and a carbide-forming element that forms a carbide more thermodynamically favorable than said rare earth carbide so as to form the rare earth -transition metal-boron compound and a carbide of said carbide-forming element as a separate carbide phase in said compound.
Dependencies are inferred from the claim text.