Computer simulation of the effect of an ultra soft phase on the magnetic properties of nanocrystalline permanent magnets |
| |
| Institution: | 1. Department of Physics and Astronomy, The University of Sheffield, Sheffield S3 7RH, UK;2. Department of Engineering Materials, The University of Sheffield, Sheffield S1 4DU, UK;1. State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, PR China;2. Sinopec Research Institute of Petroleum Engineering, Beijing, PR China;1. PCM Computational Applications, Universidad Nacional de Colombia – Sede Manizales, Manizales, Colombia;2. Facultad de Minas, Universidad Nacional de Colombia – Sede Medellín, Medellín, Colombia;1. State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation (Chengdu University of Technology), No. 1, Dongsan Road, Erxianqiao, Chenghua District, Chengdu 610059, Sichuan, PR China;2. Post-Doctoral Research Station of Geological Resource and Geological Engineering (Chengdu University of Technology), Chengdu, PR China;3. Southwest Petroleum University, Chengdu, PR China;4. Petrochina Southwest Oil and Gasfield Company, Chengdu, PR China;1. King Abdullah University of Science and Technology (KAUST), Physical Science and Engineering Division (PSE), Thuwal 23955-6900, Saudi Arabia;2. King Abdullah University of Science and Technology (KAUST), Computer, Electrical and Mathematical Science and Engineering Division (CEMSE), Thuwal 23955-6900, Saudi Arabia |
| |
| Abstract: | Micromagnetic models of assemblies of randomly oriented, exchange coupled, nanocrystals consisting of a magnetically hard uniaxial phase (typified by Nd2Fe14B) together with an ultra-soft phase (typified by α-iron) have been studied numerically. The hard crystallites were located on a three dimensional cubic lattice, and cubic crystallites of the soft phase were inserted at the junctions of every group of eight hard crystallites. Demagnetizing curves were obtained as a sequence of static equilibrium states in an incrementally changing applied field. Values of the coercivity, remanence and energy product are reported as functions of ΔGH, the grain size of the hard phase, and of ϕS, the fractional volume of the soft phase. The dependence on ΔGH falls quite rapidly with increasing ϕS. The low anisotropy and high saturation magnetization of the α-iron make approximately equal contributions to remanence enhancement in the model. Its remanence values are in quite good agreement with experimental values for Nd2Fe14B containing α-iron. However, its values for the coercivity and energy product, though decidedly lower than those obtained computationally by some other authors, significantly exceed those obtained experimentally, but show a similar variation with ΔGH and ϕS. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
