The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 28, 1995
Filed:
May. 31, 1994
Yakov Bogatin, Richboro, PA (US);
Mark Robinson, West Lawn, PA (US);
Frank S Greenwald, Woodstock, IL (US);
John Ormerod, Rockford, IL (US);
SPS Technologies, Inc., Jenkintown, PA (US);
Abstract
This invention relates to a process for producing a non-pyrophoric, corrosion resistant rare earth-containing material capable of being formed into a polymer bonded permanent magnet comprising forming particles from a rare earth-containing alloy, and treating the alloy with a passivating gas comprised of nitrogen, carbon dioxide or a combination of nitrogen and carbon dioxide at a temperature below the phase transformation temperature of the alloy, and heat treating the alloy to produce material having a coercivity of at least 1,000 Oersteds. Rare earth-containing alloys suitable for use in producing magnets, such as Nd--Fe--B and Sm--Co alloys, can be used. If nitrogen is used as the passivating gas, the resultant powder particles have a nitrogen surface concentration of from about 0.4 to about 26.8 atomic percent. Moreover, if carbon dioxide is used as the passivating gas, the resultant powder particles have a carbon surface concentration of from about 0.02 to about 15 atomic percent. The particles made in accordance with the present invention are capable of being aligned by a magnetic field to produce an anisotropic polymer bonded permanent magnet.