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. (C) 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.