Rare-earth elements in permanent magnets and superconducting compounds and alloys (except new high T c ceramics) as thin films, thin crystals and thinned bulk materials

1991 ◽  
Vol 26 (8) ◽  
pp. 1989-1999 ◽  
Author(s):  
M. Gasgnier
Keyword(s):  
Thin Films ◽  
Rare Earth ◽  
Rare Earth Elements ◽  
Permanent Magnets ◽  
Bulk Materials ◽  
Superconducting Compounds

A HYBRID MODEL ON HYSTERESIS LOOP AND COERCIVITY IN NANOSTRUCTURED PERMANENT MAGNETS

2006 ◽  
Vol 05 (04n05) ◽  
pp. 627-631 ◽  
Author(s):  
M. J. SUN ◽  
G. P. ZHAO ◽  
J. LIANG ◽  
G. ZHOU ◽  
H. S. LIM ◽  
...  
Keyword(s):  
Thin Films ◽  
Domain Wall ◽  
Grain Boundary ◽  
Magnetic Moment ◽  
Permanent Magnets ◽  
Hysteresis Loops ◽  
Bulk Materials ◽  
Rotational Model ◽  
Moment Distribution ◽  
Coercivity Mechanism

A simplified micromagnetic model has been proposed to calculate the hysteresis loops of nanostructured permanent magnets for various configurations, including thin films, exchange-coupled double-layer systems and bulk materials. The reversal part of the hysteresis is based on the Stoner–Wohlfarth coherent rotational model and the coercivity mechanism is due mainly to the motion of the transition region (a domain wall like magnetic moment distribution in the grain boundary). The elements of nucleation and pinning models are also incorporated.

scholarly journals ENHANCED PHOTOEMISSION FROM METAL NANOPARTICLE COMPOSITE THIN FILMS (Ag-BaO) DOPED WITH RARE-EARTH ELEMENTS

2001 ◽  
Vol 50 (5) ◽  
pp. 977
Author(s):  
XU BEI-XUE ◽  
WU JUN-LEI ◽  
LIU WEI-MIN ◽  
YANY HAI ◽  
SHAO QING-YI ◽  
...  
Keyword(s):  
Thin Films ◽  
Rare Earth ◽  
Rare Earth Elements ◽  
Metal Nanoparticle ◽  
Composite Thin Films

A DETERMINATION OF THE SHEAR FORCE OF THIN HIGH-COERCIVITY PERMANENT MAGNETS MADE FROM THE ALLOY WITH RARE-EARTH ELEMENTS

2021 ◽  
pp. 24-30
Author(s):  
A. Ya. Krasilʼnikov ◽  
A. A. Krasilʼnikov
Keyword(s):  
Rare Earth ◽  
Magnetic Flux ◽  
Rare Earth Elements ◽  
Standard Method ◽  
Shear Force ◽  
Permanent Magnets ◽  
High Coercivity ◽  
Research Results ◽  
Magnetic Couplings

The article considers the possibility of using a standard method for calculating the shear force of thin, high-coercivity neodymium–iron–boron type permanent magnets in magnetic clutches (couplings). The research results allowed to introduce a correction coefficients in the method of calculating the transmitting torque in magnetic clutches (couplings) with thin magnets. The possibility of 08H22N6T brand steel using for magnetic flux conductors manufacturing in a magnetic couplings.

scholarly journals Selective Roasting of Nd–Fe‒B Permanent Magnets as a Pretreatment Step for Intensified Leaching with an Ionic Liquid

2019 ◽  
Vol 6 (1) ◽  
pp. 91-102 ◽  
Author(s):  
Martina Orefice ◽  
Amy Van den Bulck ◽  
Bart Blanpain ◽  
Koen Binnemans
Keyword(s):  
Ionic Liquid ◽  
Rare Earth ◽  
Rare Earth Elements ◽  
Permanent Magnets ◽  
Metallic Phase ◽  
Process Step ◽  
Mechanical Removal ◽  
Oxidative Roasting ◽  
Roasting Temperature ◽  
The Rare Earth

AbstractOxidative roasting of Nd–Fe‒B permanent magnets prior to leaching improves the selectivity in the recovery of rare-earth elements over iron. However, the dissolution rate of oxidatively roasted Nd–Fe‒B permanent magnets in acidic solutions is very slow, often longer than 24 h. Upon roasting in air at temperatures above 500 °C, the neodymium metal is not converted to Nd2O3, but rather to the ternary NdFeO3 phase. NdFeO3 is much more difficult to dissolve than Nd2O3. In this work, the formation of NdFeO3 was avoided by roasting Nd–Fe‒B permanent magnet production scrap in argon atmosphere, having an oxygen content of $$ p_{{{\text{O}}_{2} }} \, \le \,10^{ - 20} \;{\text{atm}}, $$pO2≤10-20atm, with the addition of 5 wt% of carbon as an iron reducing agent. For all the non-oxidizing iron roasting conditions investigated, the iron in the Nd–Fe‒B scrap formed a cobalt-containing metallic phase, clearly distinct from the rare-earth phase at microscopic level. The thermal treatment was optimized to obtain a clear phase separation of metallic iron and rare-earth phase also at the macroscopic level, to enable easy mechanical removal of iron prior to the leaching step. The sample roasted at the optimum conditions (i.e., 5 wt% carbon, no flux, no quenching step, roasting temperature of 1400 °C and roasting time of 2 h) was leached in the water-containing ionic liquid betainium bis(trifluoromethylsulfonyl)imide, [Hbet][Tf2N]. A leaching time of only 20 min was sufficient to completely dissolve the rare-earth elements. The rare-earth elements/iron ratio in the leachate was about 50 times higher than the initial rare-earth elements/iron ratio in the Nd–Fe‒B scrap. Therefore, roasting in argon with addition of a small amount of carbon is an efficient process step to avoid the formation of NdFeO3 and to separate the rare-earth elements from the iron, resulting in selective leaching for the recovery of rare-earth elements from Nd–Fe‒B permanent magnets.

scholarly journals STRUCTURE, MAGNETIC AND MAGNETO-OPTICAL PEROPERTIES OF MnBi DOPED RARE EARTH ELEMENTS THIN FILMS

1993 ◽  
Vol 17 (S_1_MORIS_92) ◽  
pp. S1_99-101
Author(s):  
Fang Rui yi ◽  
Ma Ting jun ◽  
Liu Jin ◽  
Dai Dac sheng
Keyword(s):  
Thin Films ◽  
Rare Earth ◽  
Rare Earth Elements
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