您当前所在位置: 首页 > 学者

侯登录

  • 14浏览

  • 0点赞

  • 0收藏

  • 0分享

  • 189下载

  • 0评论

  • 引用

期刊论文

Studies on the magnetic viscosity and the magnetic anisotropy of γ-Fe2O3 powders

侯登录D.L. Hou X.F. Nie H.L. Luo

Appl. Phys. A 66, 109-114 (1998),-0001,():

URL:

摘要/描述

Granular γ-Fe2O3 powders, acicular γ-Fe2O3, and CoFe–γ-Fe2O3 powders are prepared by different methods. Particle shapes and mean particle sizes of samples are determined by transmission electron microscopy (TEM). Magnetic parameters are measured by a vibrating sample magnetometer (VSM) at different temperatures. Effective magnetic anisotropy constants K E of granular γ-Fe2O3 powders at different temperatures are obtained by using the law of approach to saturation (LATS). KE values of acicular γ-Fe2O3 and CoFe–γ-Fe2O3 powders are measured by a magnetotorquemeter. It is found for the first time that the variation tendency of KE with temperature for granular γ-Fe2O3 is about the same as that of shape magnetic anisotropy Ksh. Fluctuation field Hf and activation volume Vf of samples are measured. A theoretical expression of Vf is derived. For granular γ-Fe2O3 powders, calculated activation volumes are consistent with experimental ones at different temperatures. But as for acicular γ-Fe2O3 powders, calculated activation volumes are larger than experimental ones. Experimental results show that magnetization reversal of granular γ-Fe2O3 at different temperatures is close to homogeneous rotation.

关键词:

版权说明:以下全部内容由侯登录上传于   2007年05月31日 13时06分20秒,版权归本人所有。

我要评论

全部评论 0

本学者其他成果

    同领域成果