Suitable Nanostructures for Obtaining the Maximum Energy Product in Magnets

Abstract:

The existence of exchange coupling or magnetostatic coupling between two phases, one magnetically hard and other magnetically soft is a way for obtaining higher maximum energy product (BH_max). In this study, it is discussed the microstructures for obtaining either exchange coupling or magnetostatic coupling in real materials. One relevant condition is that the assumptions of the Stoner-Wohlfarth model should be obeyed, with both phases, hard and soft, with dimensions less than single domain particle size. A real possibility is enveloping a spherical grain of hard phase with a first shell of soft phase, and another second shell or layer of a paramagnetic phase. The paramagnetic phase may play relevant role promoting magnetically decoupling between the grains.

• Periodical: Materials Science Forum (Volume 869)
• Pages: 614-619
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.869.614
• Online since: August 2016
• Authors: Marcos Flavio de Campos*, Sergio Antonio Romero
• Keywords: BH_max, Exchange Coupling, Nanocrystalline, NdFeB, Remanence

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