Method of making bonded or sintered permanent magnets

Patent · Tue Aug 31 04:00:00 EDT 1993

OSTI ID:6053090

McCallum, R W; Dennis, K W; Lograsso, B K; Anderson, I E

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.

• DOE Contract Number: W-7405-ENG-82
• Assignee: Iowa State Univ. Research Foundation, Inc., Ames, IA (United States)
• Patent Number(s): A; US 5240513
• Application Number: PPN: US 7-593943
• OSTI ID: 6053090
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360101* -- Metals & Alloys-- Preparation & Fabrication
ALLOYS
BINDERS
BONDING
CARBON
CASTING MOLDS
ELEMENTAL MINERALS
ELEMENTS
FABRICATION
GRAPHITE
IRON ALLOYS
JOINING
MAGNETS
METALS
MINERALS
MIXING
NONMETALS
PARTICLE SIZE
PERMANENT MAGNETS
POWDERS
RARE EARTH ALLOYS
SINTERING
SIZE
TRANSITION ELEMENTS