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Title: Method of making bonded or sintered permanent magnets

Abstract

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.

Inventors:
 [1];  [1];  [1];  [1]
  1. Ames, IA
Issue Date:
Research Org.:
Ames Laboratory (AMES), Ames, IA; Iowa State Univ., Ames, IA (United States)
OSTI Identifier:
868901
Patent Number(s):
5240513
Application Number:
07/593,943
Assignee:
Iowa State University Research Foundation, Inc. (Ames, IA)
Patent Classifications (CPCs):
H - ELECTRICITY H01 - BASIC ELECTRIC ELEMENTS H01F - MAGNETS
DOE Contract Number:  
W-7405-ENG-82
Resource Type:
Patent
Country of Publication:
United States
Language:
English
Subject:
method; bonded; sintered; permanent; magnets; isotropic; magnet; mixing; thermally; responsive; viscosity; binder; atomized; rare; earth-transition; metal; iron; alloy; powder; carbon-bearing; graphite; layer; thereon; facilitates; wetting; bonding; particles; prior; sized; classified; provide; particular; particle; size; fraction; grain; relatively; narrow; range; selected; mixed; mixture; molded; desired; complex; shape; formed; removing; thereafter; sintering; density; size fraction; isotropic permanent; layer thereon; relatively narrow; alloy powder; permanent magnet; transition metal; rare earth; particle size; permanent magnets; grain size; powder particles; earth-transition metal; rare earth-transition; selected particle; molded mixture; particular particle; net shape; narrow range; thermally responsive; sintered permanent; viscosity binder; atomized rare; /148/75/252/419/427/

Citation Formats

McCallum, R William, Dennis, Kevin W, Lograsso, Barbara K, and Anderson, Iver E. Method of making bonded or sintered permanent magnets. United States: N. p., 1993. Web.
McCallum, R William, Dennis, Kevin W, Lograsso, Barbara K, & Anderson, Iver E. Method of making bonded or sintered permanent magnets. United States.
McCallum, R William, Dennis, Kevin W, Lograsso, Barbara K, and Anderson, Iver E. Fri . "Method of making bonded or sintered permanent magnets". United States. https://www.osti.gov/servlets/purl/868901.
@article{osti_868901,
title = {Method of making bonded or sintered permanent magnets},
author = {McCallum, R William and Dennis, Kevin W and Lograsso, Barbara K and Anderson, Iver E},
abstractNote = {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.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Jan 01 00:00:00 EST 1993},
month = {Fri Jan 01 00:00:00 EST 1993}
}

Works referenced in this record:

New material for permanent magnets on a base of Nd and Fe (invited)
journal, March 1984


Permanent magnet materials based on the rare earth-iron-boron tetragonal compounds
journal, September 1984


Hot‐pressed neodymium‐iron‐boron magnets
journal, April 1985


The metal injection molding process comes of age
journal, August 1989


Processing of Neodymium-Iron-Boron melt-spun ribbons to fully dense magnets
journal, September 1985


Iron‐based rare‐earth magnets (invited)
journal, April 1985