The Coercivity Mechanisms in Sm(CoFeCuZr)z Nanocrystalline Magnets: Nucleation x Pinning

Marcos Flavio de Campos

doi:10.4028/www.scientific.net/MSF.591-593.8

Paper Titles

Committees

Foreword

Estimative of the Stacking Fault Energy for a FeNi(50/50) Alloy and a 316L Stainless Steel
p.3

The Coercivity Mechanisms in Sm(CoFeCuZr)z Nanocrystalline Magnets: Nucleation x Pinning
p.8

Ga-Modified Nanostructured ZnO: Characterization and Application in Dye-Sensitized Solar Cells
p.13

Corrosion Resistance and Cytotoxicity Study of 17-4PH Steels Produced by Conventional Metallurgy and Powder Injection Molding
p.18

Ti-13Nb-13Zr Foams for Surgical Implants
p.24

A Comparison between CoNiCrAlY Bond Coat and Zirconia Plasma Sprayed Coatings on Creep Tests
p.30

Porosity Characterization of Sintered Titanium Scaffolds for Surgical Implants
p.36

HomeMaterials Science ForumMaterials Science Forum Vols. 591-593The Coercivity Mechanisms in Sm(CoFeCuZr)z...

The Coercivity Mechanisms in Sm(CoFeCuZr)z Nanocrystalline Magnets: Nucleation x Pinning

Abstract:

It is discussed the difference between the magnetic reversal mechanisms: i) coherent rotation, ii) nucleation, iii) unpinning of domain walls. The main argument to suggest pinning as the coercivity mechanism of Sm(CoFeCuZr)z magnets is the low initial susceptibility of magnetization curves of thermally demagnetized magnets. However, coherent rotation also implies in low initial susceptibility, since the grain size of the magnets is near the single domain particle size. It is unlikely that pinning could be the coercivity mechanism in this case, since the anisotropy field of Sm2Co17 phase is 65 kOe, whereas the coercivity of magnets can be higher than 40 kOe. Such coercive field of 60% of the anisotropy field indicates coherent rotation as mechanism. A model for describing the abnormal coercivity behavior in Sm(CoFeCuZr)z magnets is proposed.