Anomalous magnetic viscosity in alpha-Fe(Co)/(Nd,Pr)(2)Fe14B exchange-spring magnet

作者：Nguyen Hoang Hai^*; Nguyen Chau; Duc The Ngo; Duong Thi Hong Gam

来源：Journal of Magnetism and Magnetic Materials, 2011, 323(23): 3156-3161.

DOI：10.1016/j.jmmm.2011.07.002

• Magnetic relaxation
• Exchange spring magnet
• Hard magnetic material
• Magnetic viscosity
• Magnetic reversal

This article presents an anomalous magnetic viscosity in alpha-Fe(Co)/(Nd,Pr)(2)Fe14B exchange-spring magnet. A similar effect has been observed in non-interacting or weakly interacting systems but not in a strong interacting magnetic systems. We reported a new procedure to measure magnetic relaxation under various magnetic fields. Changing the applied magnetic field by different field protocols during the reversal process, we found that a memory effect of the magnetization appeared if the field change is large enough. The mechanism of the phenomenon can be explained in the model of conventional magnetic reversal in strong ferromagnetic systems with an energy barrier distribution. The study of such magnetic relaxations can provide some information related to the energy barrier distribution function.

• 出版日期2011-12