Iron-based rare-earth magnets (invited)

Rare-earth iron alloys offer promise for the realization of the highest-energy product attainable. We have investigated rare-earth iron alloys by melt spinning and identified compositions that are beneficial for magnet fabrication. Compositions of the type R3Fe16B and R3Fe20B provide high values of coercive force. Processing of the compositions into magnets resulted in energy product of up to 45 MG Oe with a potential for 47.5 MG Oe. The B-H loop characteristics indicate that these magnets can be used up to 150 °C.