Effect of high magnetic field on the coercivity in sintered Nd-Fe-B magnets

• Published in: Journal of magnetism and magnetic materials Vol. 310; no. 2; pp. 2596 - 2598
• Main Authors: Kato, H., Akiya, T., Sagawa, M., Koyama, K., Miyazaki, T.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Amsterdam Elsevier B.V 01.03.2007; Elsevier Science
• Subjects: Coercivity; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Domain effects, magnetization curves, and hysteresis; Exact sciences and technology; High magnetic field; Magnetic properties and materials; Magnetization curves, magnetization reversal, hysteresis, barkhausen and related effects; Nd-Fe-B magnet; Physics; High magnetic field; Nd-Fe-B magnet; Coercivity; Differential scanning calorimetry; Annealing; Ternary alloys; Magnetic field effects; Ferromagnetic materials; Neodymium alloys; Boron alloys; Impurities; Sintering; Coercive force; High field; Anomaly; Iron base alloys
• ISSN: 0304-8853
• DOI: 10.1016/j.jmmm.2006.11.004

An influence of a 140 kOe magnetic field applied during the last-stage annealing process was investigated in Dy-free Nd-Fe-B sintered magnets. When a sample containing small amount of Cu and Al was annealed at T a = 500 and 550 ∘ C under a magnetic field of H a = 140 kOe , the coercivity H c increased by 20% and 16%, respectively, as compared with the control sample annealed at zero field. DSC data of this sample showed anomalies around 500 and 540 ∘ C . These results were discussed in terms of a field-induced change in interface matching between Nd 2Fe 14B and intergranular phases.