Patents by Inventor R. William McCallum
R. William McCallum has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 11462358Abstract: The invention provides method for making high coercivity magnetic materials based on FeNi alloys having a L10 phase structure, tetratenite, and provides a system for accelerating production of these materials. The FeNi alloy is made by preparing a melt comprising Fe, Ni, and optionally one or more elements selected from the group consisting of Ti, V, Al, B, C, Mo, Ir, and Nb; cooling the melt and applying extensional stress and a magnetic field. This is followed by heating and cooling to form the L10 structure.Type: GrantFiled: August 20, 2018Date of Patent: October 4, 2022Inventors: Laura H. Lewis, Ian J. McDonald, Sahar Keshavarz, R. William McCallum
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Publication number: 20210035733Abstract: The invention provides method for making high coercivity magnetic materials based on FeNi alloys having a Llo phase structure, tetratenite, and provides a system for accelerating production of these materials. The FeNi alloy is made by preparing a melt comprising Fe, Ni, and optionally one or more elements selected from the group consisting of Ti, V, Al, B, C, Mo, Ir, and Nb; cooling the melt and applying extensional stress and a magnetic field. This is followed by heating and cooling to form the L10 structure.Type: ApplicationFiled: August 20, 2018Publication date: February 4, 2021Inventors: Laura H. LEWIS, Ian J. McDONALD, Sahar KESHAVARZ, R. William McCALLUM
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Patent number: 10586640Abstract: A bulk high performance permanent magnet comprising a neodymium-iron-boron core having an outer surface, and a coercivity-enhancing element residing on at least a portion of said outer surface, with an interior portion of said neodymium-iron-boron core not having said coercivity-enhancing element therein. Also described herein is a method for producing the high-coercivity bulk permanent magnet, the method comprising: (i) depositing a coercivity-enhancing element on at least a portion of an outer surface of a neodymium-iron-boron core substrate to form a coated permanent magnet; and (ii) subjecting the coated permanent magnet to a pulse thermal process that heats said outer surface to a substantially higher temperature than an interior portion of said neodymium-iron-boron core substrate, wherein said substantially higher temperature is at least 200° C.Type: GrantFiled: January 25, 2017Date of Patent: March 10, 2020Assignees: UT-BATTELLE, LLC, IOWA STATE UNIVERSITY RESEARCH FOUNDATION, INC., LAWRENCE LIVERMORE NATIONAL SECURITY, LLCInventors: Mariappan Parans Paranthaman, Michael A. McGuire, David S. Parker, Orlando Rios, Brian C. Sales, Huseyin Ucar, Scott K. McCall, R. William McCallum, Cajetan I. Nlebedim
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Publication number: 20180229442Abstract: A method for producing a bonded permanent magnet, comprising: (i) incorporating a solid precursor material comprising a thermoplastic crosslinkable polymer and magnetic particles into an additive manufacturing device, wherein the crosslinkable polymer has a delayed crosslinking ability; (ii) melting the precursor material by heating it to a temperature of at least and no more than 10° C. above its glass transition temperature; (iii) extruding the melt through the additive manufacturing device and, as the extrudate exits from the nozzle and is deposited on a substrate as a solidified preform of a desired shape, exposing the resultant extrudate to a directional magnetic field of sufficient strength to align the magnetic particles; and (iv) curing the solidified preform by subjecting it to conditions that result in crosslinking of the thermoplastic crosslinkable polymer to convert it to a crosslinked thermoset. The resulting bonded permanent magnet and articles made thereof are also described.Type: ApplicationFiled: February 14, 2017Publication date: August 16, 2018Inventors: Huseyin UCAR, Mariappan Parans PARANTHAMAN, Orlando RIOS, Belther Mojoko MONONO, Brian K. POST, Vlastimil KUNC, Cajetan I. NLEBEDIM, R. William MCCALLUM, Scott K. MCCALL
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Publication number: 20170213626Abstract: A bulk high performance permanent magnet comprising a neodymium-iron-boron core having an outer surface, and a coercivity-enhancing element residing on at least a portion of said outer surface, with an interior portion of said neodymium-iron-boron core not having said coercivity-enhancing element therein. Also described herein is a method for producing the high-coercivity bulk permanent magnet, the method comprising: (i) depositing a coercivity-enhancing element on at least a portion of an outer surface of a neodymium-iron-boron core substrate to form a coated permanent magnet; and (ii) subjecting the coated permanent magnet to a pulse thermal process that heats said outer surface to a substantially higher temperature than an interior portion of said neodymium-iron-boron core substrate, wherein said substantially higher temperature is at least 200° C.Type: ApplicationFiled: January 25, 2017Publication date: July 27, 2017Inventors: Mariappan Parans PARANTHAMAN, Michael A. MCGUIRE, David S. PARKER, Orlando RIOS, Brian C. SALES, Huseyin UCAR, Scott K. MCCALL, R. William MCCALLUM, Cajetan I. NLEBEDIM
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Patent number: 6352649Abstract: The present invention provides magnetostrictive composites that include an oxide ferrite and metallic binders which provides mechanical properties that make the magnetostrictive compositions effective for use as sensors and actuators.Type: GrantFiled: April 17, 2000Date of Patent: March 5, 2002Assignee: Iowa State University Research Foundation Inc.Inventors: R. William McCallum, John E. Snyder, Kevin W. Dennis, Carl R. Schwichtenberg, David C. Jiles
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Patent number: 6093337Abstract: The present invention provides magnetostrictive compositions that include an oxide ferrite which provides mechanical properties that make the magnetostrictive compositions effective for use as sensors and actuators.Type: GrantFiled: October 1, 1998Date of Patent: July 25, 2000Assignee: Iowa State University Research Foundation, Inc.Inventors: R. William McCallum, John E. Snyder, Kevin W. Dennis, Carl R. Schwichtenberg, David C. Jiles
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Patent number: 5803992Abstract: A method of making a permanent magnet wherein 1) a melt is formed having a base alloy composition comprising RE, Fe and/or Co, and B (where RE is one or more rare earth elements) and 2) TR (where TR is a transition metal selected from at least one of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, and Al) and at least one of C and N are provided in the base alloy composition melt in substantially stoichiometric amounts to form a thermodynamically stable compound (e.g. TR carbide, nitride or carbonitride). The melt is rapidly solidified in a manner to form particulates having a substantially amorphous (metallic glass) structure and a dispersion of primary TRC, TRN and/or TRC/N precipitates. The amorphous particulates are heated above the crystallization temperature of the base alloy composition to nucleate and grow a hard magnetic phase to an optimum grain size and to form secondary TRC, TRN and/or TRC/N precipitates dispersed at grain boundaries.Type: GrantFiled: November 29, 1995Date of Patent: September 8, 1998Assignee: Iowa State University Research Foundation, Inc.Inventors: R. William McCallum, Daniel J. Branagan
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Patent number: 5690889Abstract: 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.Type: GrantFiled: February 15, 1996Date of Patent: November 25, 1997Assignee: Iowa State University Research Foundation, Inc.Inventors: R. William McCallum, Timothy W. Ellis, Kevin W. Dennis, Robert J. Hofer, Daniel J. Branagan
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Patent number: 5486240Abstract: A method of making a permanent magnet wherein 1) a melt is formed having a base alloy composition comprising RE, Fe and/or Co, and B (where RE is one or more rare earth elements) and 2) TR (where TR is a transition metal selected from at least one of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, and Al) and at least one of C and N are provided in the base alloy composition melt in substantially stoichiometric amounts to form a thermodynamically stable compound (e.g. TR carbide, nitride or carbonitride). The melt is rapidly solidified in a manner to form particulates having a substantially amorphous (metallic glass) structure and a dispersion of primary TRC, TRN and/or TRC/N precipitates. The amorphous particulates are heated above the crystallization temperature of the base alloy composition to nucleate and grow a hard magnetic phase to an optimum grain size and to form secondary TRC, TRN and/or TRC/N precipitates dispersed at grain boundaries.Type: GrantFiled: April 25, 1994Date of Patent: January 23, 1996Assignee: Iowa State University Research Foundation, Inc.Inventors: R. William McCallum, Daniel J. Branagan
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Patent number: 5470401Abstract: An isotropic permanent magnet is made by mixing a thermally responsive, low viscosity binder and atomized rare earth-transition metal (e.g., iron) alloy powder having a carbon-bearing (e.g., graphite) layer thereon that facilitates wetting and bonding of the powder particles by the binder. Prior to mixing with the binder, the atomized alloy powder may be sized or classified to provide a particular particle size fraction having a grain size within a given relatively narrow range. A selected particle size fraction is mixed with the binder and the mixture is molded to a desired complex magnet shape. A molded isotropic permanent magnet is thereby formed. A sintered isotropic permanent magnet can be formed by removing the binder from the molded mixture and thereafter sintering to full density.Type: GrantFiled: July 26, 1993Date of Patent: November 28, 1995Assignee: Iowa State University Research Foundation, Inc.Inventors: R. William McCallum, Kevin W. Dennis, Barbara K. Lograsso, Iver E. Anderson
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Patent number: 5433978Abstract: A method of making quasicrystalline alloy particulates wherein an alloy is superheated and the melt is atomized to form generally spherical alloy particulates free of mechanical fracture and exhibiting a predominantly quasicrystalline in the atomized condition structure. The particulates can be plasma sprayed to form a coating or consolidated to form an article of manufacture.Type: GrantFiled: September 27, 1993Date of Patent: July 18, 1995Assignee: Iowa State University Research Foundation, Inc.Inventors: Jeffrey E. Shield, Alan I. Goldman, Iver E. Anderson, Timothy W. Ellis, R. William McCallum, Daniel J. Sordelet
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Patent number: 5242508Abstract: A method for making an isotropic permanent magnet comprises atomizing a melt of a rare earth-transition metal alloy (e.g., an Nd--Fe--B alloy enriched in Nd and B) under conditions to produce protectively coated, rapidly solidified, generally spherical alloy particles wherein a majority of the particles are produced/size classified within a given size fraction (e.g., 5 to 40 microns diameter) exhibiting optimum as-atomized magnetic properties and subjecting the particles to concurrent elevated temperature and elevated isotropic pressure for a time effective to yield a densified, magnetically isotropic magnet compact having enhanced magnetic properties and mechanical properties.Type: GrantFiled: April 15, 1992Date of Patent: September 7, 1993Assignee: Iowa State University Research Foundation, Inc.Inventors: R. William McCallum, Kevin W. Dennis, Barbara K. Lograsso, Iver E. Anderson
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Patent number: 5240513Abstract: An isotropic permanent magnet is made by mixing a thermally responsive, low viscosity binder and atomized rare earth-transition metal (e.g., iron) alloy powder having a carbon-bearing (e.g., graphite) layer thereon that facilitates wetting and bonding of the powder particles by the binder. Prior to mixing with the binder, the atomized alloy powder may be sized or classified to provide a particular particle size fraction having a grain size within a given relatively narrow range. A selected particle size fraction is mixed with the binder and the mixture is molded to a desired complex magnet shape. A molded isotropic permanent magnet is thereby formed. A sintered isotropic permanent magnet can be formed by removing the binder from the molded mixture and thereafter sintering to full density.Type: GrantFiled: October 9, 1990Date of Patent: August 31, 1993Assignee: Iowa State University Research Foundation, Inc.Inventors: R. William McCallum, Kevin W. Dennis, Barbara K. Lograsso, Iver E. Anderson
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Patent number: 4637967Abstract: The present invention provides an electrode which uses a disordered active material preferably formed by rapid solidification. The active material does not need a binder to be used as an electrode, and thus, is considered self-supporting. The material also is substantially non-porous or impermeable to an electrolyte and when used as an electrode exhibits an increase in cell capacity with improved resistance to corrosion. An electrode of the present invention provides greatly improved cycle life and energy density without a significant decrease in cell capacity. Methods of making the electrode by rapidly solidifying a disordered material are also included. A method of assembling an electrochemical cell using a self-supporting electrode includes the step of producing a disordered active material and aligning the material in a predetermined position in a cell casing.Type: GrantFiled: August 29, 1985Date of Patent: January 20, 1987Assignee: Energy Conversion Devices, Inc.Inventors: John E. Keem, Richard C. Bergeron, Russell C. Custer, R. William McCallum