HYSTERESIS LOOPS AT DIFFERENT TEMPERATURES FOR MELT-SPUN ND13FE77B10

Citation
Hm. Jin et al., HYSTERESIS LOOPS AT DIFFERENT TEMPERATURES FOR MELT-SPUN ND13FE77B10, Journal of physics. Condensed matter, 10(32), 1998, pp. 7243-7258
Citations number
14
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physics, Condensed Matter
ISSN journal
0953-8984
Volume
10
Issue
32
Year of publication
1998
Pages
7243 - 7258
Database
ISI
SICI code
0953-8984(1998)10:32<7243:HLADTF>2.0.ZU;2-H
Abstract
Hysteresis loops of melt-spun Nd13Fe77B10 were measured at different t emperatures between 4.2 K and 250 K. The loops were analysed on the ba sis of the micromagnetism using the finite element technique. By fitti ng the calculated H-i(c), with the experiment, the value of the exchan ge constant across the inter-grain boundary was estimated to be about 90% of that across the inner-grain boundary, H-i(c), increases to a ma ximum at the spin reorientation temperature T-s and then decreases wit h increasing temperature. With decrease of the exchange interaction ac ross the grain boundary, H-i(c), decreases below T-s, and increases ab ove T-s, and the Stoner-Wohlfarth model provides the theoretical lower and upper limits of H-i(c), below and above T-s, respectively. The ca lculations reproduce the hysteresis loops fairly well. The magnetizati on proceeds by noncoherent rotation, and the spin distribution becomes quite non-uniform in some grains when H decreases to near H-i(c).