Jumps of magnetic polarization in Sm/sub 2/Co/sub 17/-based magnets
作者： A. Handstein , D. Eckert , K.-H. Muller , B. Wall , W. Rodewald
DOI: 10.1109/20.312347
关键词: Coercivity 、 Magnetic hysteresis 、 Curie temperature 、 Materials science 、 Helium 、 Heat capacity 、 Demagnetizing field 、 Magnetization 、 Condensed matter physics 、 Thermal conductivity
摘要: At temperatures below 8.2 K large spontaneous jumps in the demagnetization curve of Sm/sub 2/(Co,Cu,Fe,Zr)/sub 17/ magnets with high coercivity were detected. For different samples no correlations concerning onset, depth or number could be observed. Systematic investigations showed following results: i) The emergence and depend on temperature, field sweeping rate sample dimensions. ii) onset is shifted to smaller applied fields decreasing temperature. iii) cooling conditions have a strong influence. These results definitely shown that observed polarization are due thermal instabilities because small heat capacity poor conductivity agreement local heating model. >
osti.gov 
sci-hub.se 参考文章(6)
K.-D. Durst, H. Kronmüller, W. Ervens, Investigations of the magnetic properties and demagnetization processes of an extremely high coercive Sm (Co, Cu, Fe, Zr)7.6 permanent magnet II. The coercivity mechanism Physica Status Solidi (a). ,vol. 108, pp. 705- 719 ,(1988) , 10.1002/PSSA.2211080228
M. Uehara, B. Barbara, Noncoherent quantum effects in the magnetization reversal of a chemically disordered magnet : SmCo3.5Cu1.5 Journal De Physique. ,vol. 47, pp. 235- 238 ,(1986) , 10.1051/JPHYS:01986004702023500
Y. Otani, H. Miyajima, S. Chikazumi, Large Barkhausen jumps observed in Nd-Fe-B sintered magnets at very low temperatures IEEE Transactions on Magnetics. ,vol. 25, pp. 3431- 3433 ,(1989) , 10.1109/20.42325
Yoshichika Otani, J. M. D. Coey, B. Barbara, Hideki Miyajima, Soshin Chikazumi, M. Uehara, Anomalous demagnetization process at very low temperature in Nd‐Fe‐B magnets Journal of Applied Physics. ,vol. 67, pp. 4619- 4621 ,(1990) , 10.1063/1.344831
Y. Nakagawa, H. Hiroyoshi, M. Sagawa, S. Hirosawa, K. Tokuhara, High-field hysteresis loop of Nd-Fe-B magnet and related materials IEEE Transactions on Magnetics. ,vol. 23, pp. 2530- 2532 ,(1987) , 10.1109/TMAG.1987.1065346
G. C. Hadjipanayis, K. R. Lawless, R. C. Dickerson, Magnetic hardening in iron‐neodymium‐boron permanent magnets Journal of Applied Physics. ,vol. 57, pp. 4097- 4099 ,(1985) , 10.1063/1.334630