Permanent magnets: Plugging the gap

Bulk permanent magnets are indispensable components of numerous consumer and industrial products for energy conversion. The market splits roughly 2:1 between Nd–Fe–B and hard ferrite, whose costs are currently in a ratio of more than 25:1. The escalation of rare earth costs presents an opportunity for new magnets with an energy product of 100–200 kJ m−3, intermediate between ferrite (<38 kJ m−3) and Nd–Fe–B (>200 kJ m−3), provided the costs of raw materials and manufacturing are kept low.