Open AccessSURFACE EFFECTS ON SATURATION MAGNETIZATION OF FINE γ-Fe2O3 PARTICLES
Author(s) -
Luo He-Lie,
Wen Yiting,
Kening Sun,
Feng Yuan-Bing,
Huang Xicheng
Publication year - 1983
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.32.812
Subject(s) - saturation (graph theory) , magnetization , condensed matter physics , magnetic moment , magnetic field , materials science , magnetic particle inspection , surface (topology) , moment (physics) , physics , classical mechanics , geometry , mathematics , quantum mechanics , combinatorics
Fine γ-Fe2O3 particles with diameter of 80-700? were prepared. Their saturation magnetization per unit mass σs and specific surface area Sa were measured. An empirical formula σs(s) = σs(∞(1-aSa) was obtained. It was proposed that the fine particles consist of two parts: the first part is the surface layer, whose magnetic moment can not be turned entirely to the field direction by the applied magnetic field, but make an average angle (canting angle) with the field. The second is the inner part of the particles, whose magnetic moment can be aligned along the direction of the applied magnetic field. The above empirical formula can be interpreted very well by this simple model.