Squareness of NdFeB Stoner-Wohlfarth Hysteresis

Abstract:

Hysteresis curves were calculated according the Stoner-Wohlfarth (SW) model using values of K₂/K₁ from zero up to 0.25 (where K₂ is the 2^nd order anisotropy constant and where K₁ is the 1^st order anisotropy constant). The SW calculations assume Nd₂Fe₁₄B nanocrystalline magnets with single domain particle size (grain diameter less than 150 nm). The effect of K₂ on several index of merit of magnets as BH_max and squareness are discussed. As a general result, increasing K₂, the intrinsic coercivity increases. However, the increase of K₂ almost does not improve the BH_max of isotropic magnets. It is found that the effect of the K₂/K₁ ratio is coupled with the effect of texture, i.e., the effect of K₂ is more significant for pronounced texture.

• Periodical: Materials Science Forum (Volume 802)
• Pages: 601-606
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.802.601
• Online since: December 2014
• Authors: Marcos Flavio de Campos, Fernanda A.S. da Silva, Jose Adilson de Castro
• Keywords: Coercivity, Hysteresis, Magnets, NdFeB

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