MAGNETIC STRUCTURE AND MAGNETIC IMAGING OF RE{sub 2}Fe{sub 14}B (RE=Nd,Pr) PERMANENT MAGNETS
This chapter aims to review the magnetic structures observed in the RE{sub 2}Fe{sub 14}B (RE = Nd, Pr) system using various TEM magnetic imaging techniques. The authors focus on studies of die-upset Nd-based permanent magnets conducted mainly at Brookhaven National Laboratory in the past several years. Investigations on Nd-Fe-B sintered magnets and single crystals, as well as Pr-Fe-B die-upset magnets also will be covered. In Sec.2 and Sec.3 they review the microstructure, including grain alignment and secondary phases of the materials, and grain boundary structure and composition of the intergranular phase. Sec.4 is devoted to the domain structure, such as the width of domain and domain wall and domain-wall energy. Monte Carlo simulation of the effects of demagnetization fields will be presented in Sec.5. In-situ experiments on the dynamic behavior of domain reorientation as a function of temperature, pinning, grain boundary nucleation related to coercivity under various fields are described in Sec.6. Finally, in Sec.7 the correlation between microstructure and properties are discussed.
- Research Organization:
- Brookhaven National Lab. (BNL), Upton, NY (United States)
- Sponsoring Organization:
- USDOE Office of Energy Research (ER) (US)
- DOE Contract Number:
- AC02-98CH10886
- OSTI ID:
- 757139
- Report Number(s):
- BNL-67350; KC020101; R&D Project: AS015MSD; KC020101; TRN: US0005166
- Resource Relation:
- Other Information: PBD: 20 Apr 2000; Related Information: In: Experimental methods in the physical sciences. Volume 36: Magnetic imaging and its applications to materials, by Degraef, M; Zhu, Y, vp.
- Country of Publication:
- United States
- Language:
- English
Similar Records
Magnetization process in rapidly solidified neodymium-iron-boron permanent magnet materials
Die-upset Pr-Fe-B-type magnets from melt-spun ribbons