Van der Waals-Zeeman Colloquium

Thursday, 21 Jun 2007, 16:00h

Building bulk magnets with nanoparticles

Prof. J.P. Liu
Department of Physics, University of Texas at Arlington, Arlington, TX 76019, USA

Theoretic calculations have predicted very high energy products - the figure of merit of permanent magnets, for exchange-coupled nanocomposite magnets. Progress in our experiments has been made recently by adopting a "bottom-up" approach to fabricate the nanocomposite magnets. The first step of this novel approach involves synthesis and characterization of hard and soft magnetic nanoparticles. Mixed powder particles were then consolidated with unconventional compaction techniques. Thanks to the well controlled particle size and grain size, strong magnetic exchange coupling has been achieved between the hard and the soft magnetic phases, which makes this approach promising for producing bulk nanocomposite magnets with enhanced energy products.