| 摘要 |
This invention relates to a process for producing a rare earth-containing material capable of being formed into a permanent magnet having an increased Curie temperature comprising treating the alloy with a passivating gas at a temperature below the phase transformation temperature of the alloy, such that the Curie temperature of the material is increased when the material is formed into a permanent magnet. Rare earth-containing alloys, such as Nd-Fe-B and Sm-Co alloys, can be used. The passivating gas can be nitrogen, carbon dioxide or a combination thereof. The improved permanent magnet can have a nitrogen surface concentration of from about 0.4 to about 26.8 atomic percent if nitrogen is used as the passivating gas. The improved permanent magnet can also have a carbon surface concentration of from about 0.02 to about 15 atomic percent if carbon dioxide is used as the passivating gas. |
