Inventors:
Yakov Bogatin - Richboro PA
Mark Robinson - West Lawn PA
Frank S. Greenwald - Woodstock IL
John Ormerod - Rockford IL
Assignee:
SPS Technologies, Inc. - Jenkintown PA
International Classification:
H01F 1055
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.