Tan X H, Chan S F, Han K, Xu H
Laboratory for microstructures, School of Materials Science and Engineering, Shanghai University, Shanghai 200444, P. R. China.
National High Magnetic Field Laboratory, Florida State University, 1800 E. Paul Dirac Drive, Tallahassee, FL 32310, USA.
Sci Rep. 2014 Oct 28;4:6805. doi: 10.1038/srep06805.
Understanding the coercivity mechanism has a substantial impact on developing novel permanent materials. However, the current coercivity mechanisms used widely in permanent alloys cannot explain well the amorphous phase produced hard magnetic behavior of Nd-based bulk amorphous alloys (BAAs). Here, we propose that the coercivity in as-cast Nd60Fe30Al10 alloy is from the combination of magnetic interaction and strong pinning of domain walls. Moreover, the role of domain wall pinning is less affected after crystallization, while the magnetic interaction is dependent on the annealing temperature. Our findings give further insight into the coercivity mechanism of Nd-based bulk ferromagnets and provide a new idea to design prospective permanent alloys with coercivity from the combination of magnetic interaction and pinning of domain walls.
理解矫顽力机制对新型永磁材料的开发具有重大影响。然而,目前在永磁合金中广泛使用的矫顽力机制并不能很好地解释非晶相产生的钕基块状非晶合金(BAA)的硬磁行为。在此,我们提出铸态Nd60Fe30Al10合金中的矫顽力来自磁相互作用和畴壁的强钉扎作用的结合。此外,畴壁钉扎的作用在结晶后受影响较小,而磁相互作用则取决于退火温度。我们的研究结果进一步深入了解了钕基块状铁磁体的矫顽力机制,并为设计具有磁相互作用和畴壁钉扎相结合的矫顽力的前瞻性永磁合金提供了新思路。