Method of making permanent magnets

Patent · Tue Sep 07 00:00:00 EDT 1993

OSTI ID:5440720

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

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. 13 figures.

• DOE Contract Number: W-7405-ENG-82
• Assignee: Iowa State Univ. Research Foundation, Inc., Ames, IA (United States)
• Patent Number(s): US 5242508; A
• Application Number: PPN: US 7-869897
• OSTI ID: 5440720
• Resource Relation: Patent File Date: 15 Apr 1992
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
42 ENGINEERING
BORON ALLOYS
FABRICATION
MAGNETIC PROPERTIES
IRON ALLOYS
NEODYMIUM ALLOYS
PERMANENT MAGNETS
ATOMIZATION
PARTICLE SIZE
SOLIDIFICATION
ALLOYS
MAGNETS
PHASE TRANSFORMATIONS
PHYSICAL PROPERTIES
RARE EARTH ALLOYS
SIZE
360101* - Metals & Alloys- Preparation & Fabrication
360104 - Metals & Alloys- Physical Properties
420200 - Engineering- Facilities
Equipment
& Techniques