Critical phenomenon in soft magnetic properties of giant magnetostrictive materials: Computer simulation
Critical phenomenon in soft magnetic properties of giant magnetostrictive materials: Computer simulation
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DOI：
10.1063/1.2176311
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发表时间：
2006-04
影响因子：
3.2
通讯作者：
H. Fukunaga;Takayuki Yamaguchi
中科院分区：
文献类型：
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作者：
H. Fukunaga;Takayuki Yamaguchi
数值计算了各向同性超磁致伸缩材料的磁致伸缩性能和磁性能随晶粒尺寸的变化关系。模型磁体由8000个立方（Tb0.3Dy0.7）Fe2晶粒组成。在考虑各向异性、交换、磁弹性、弹性和塞曼能量的情况下，确定了每个晶粒的磁化方向和磁致伸缩。随后，通过改变外加磁场，得到了磁滞回线和磁致伸缩随外加磁场的变化曲线。随着晶粒尺寸D的减小，磁致伸缩系数Hc和dλ scindH（λ为磁致伸缩系数）在D=25nm处急剧减小。这种软磁性能的改善超过了Herzer计算的预期改善，其中Hc与D6成比例。为了详细研究显着的改善，我们计算了不同的磁致伸缩和各向异性常数的磁和磁致伸缩性能。结果，它是清晰的...
Dependence of magnetostrictive and magnetic properties on grain size was calculated numerically for an isotropic giant magnetostrictive material. The model magnet assumed is composed of 8000 cubic (Tb0.3Dy0.7)Fe2 grains. The direction of magnetization and the magnetostriction of each grain was determined for a given applied field under the consideration of the anisotropy, exchange, magnetoelastic, elastic, and Zeeman energies. Subsequently, the hysteresis loop and the magnetostriction versus applied field curve was obtained by varying the applied field. With decreasing the grain size D, the coercivity Hc and dλ∕dH, where λ is the magnetostriction, decreased abruptly at D=25nm. This improvement in soft magnetic properties exceeded the expected improvement from Herzer’s calculation, in which Hc was proportional to D6. In order to study the significant improvement in detail, we calculated magnetic and magnetostrictive properties with varying magnetostriction and anisotropy constants. Resultantly, it was clar...