ORALS
SESSION:
SISAMSatPM2-R3
H: Characterization cont. | Kobe International Symposium on Science of Innovative and Sustainable Alloys and Magnets (5th Intl. Symp. on Science of Intelligent and Sustainable Advanced Materials (SISAM)) |
| Sat Oct, 26 2019 / Room: Dr. Christian Bernard | |
| Session Chairs: Petra Jenus; Session Monitor: TBA |
16:45: [SISAMSatPM211]
Metal-Bonded Magnets Based on YCo5-Type Nanocrystals Marko
Soderžnik1 ; Matic
Korent
2 ;
Kristina
Zagar Soderznik3 ;
Jean-marie
Dubois4 ; Pelin
Tozman
5 ; M.
Venkatesan
6 ; Michael
Coey
7 ;
Spomenka
Kobe8 ;
1Jožef Stefan Institute, Ljubljana, Slovenia;
2Jozzef Stefan Institute, LJUBLJANA, Slovenia;
3Jozef Stefan Institute, Ljubljana, Slovenia;
4JSI - K7 Dpt for Nanostructured Materials, Ljubljana, Slovenia;
5NIMS, Tsukuba, Japan;
6School of Physics and CRANN, Trinity College, Dublin, Ireland;
7School of Physics, Dublin, Ireland;
8Josef Stefan Institute, Ljubljana, Slovenia;
Paper Id: 342
[Abstract] Metal-bonded magnets based on YCo<sub>5</sub>-type nanocrystals [i] were produced by hot-compaction using a spark plasma-sintering device. Zn and Zn/Al metallic binders with a melting temperature of ̴ 420°C were employed to fabricate dense cylindrical magnets. Two different pressures were used for compaction. The pressure of 400 MPa provided a metal-bonded magnet with Vickers hardness (HV10) of 460 ± 20 Vickers. The temperature coefficients for remanence (α) and coercivity (β) were derived from magnetization vs. magnetic field measurements in the temperature range of 20°C – 150°C. Temperature coefficients α and β for the Zn/Al-bonded magnet pressed with 400 MPa were -0.055 %/°C and -0.201 %/°C, respectively. The field emission gun scanning electron microscope revealed a ‘core-shell’-type microstructure. The pure YCo<sub>4.8</sub>Fe<sub>0.2</sub> phase was detected in the core region whereas the shell was enriched with non-ferromagnetic Zn or Zn/Al phases. The high-resolution transmission electron microscope revealed the presence of clusters with ̴ 20 nm YCo<sub>4.8</sub>Fe<sub>0.2</sub> grains. In the Zn/Al-bonded magnet, fabricated at 400 MPa, the coercivity <i>µ<sub>0</sub>H<sub>ci</sub></i>, remanent magnetization σ and energy product (BH)<sub>max</sub> were 0.87 T, 39.3 Am<sup>2</sup>/kg and 23.4 kJ/m<sup>3</sup>, respectively.[ii]
References:
[i] P. Tozman, M. Venkatesan, J. M. D. Coey, Optimization of the magnetic properties of nanostructured Y-Co-Fe alloys for permanent magnets, AIP Adv. 6 (2016) 056016.\n[ii] M. Soderžnik, M. Korent, K. Žagar Soderžnik, J.-M. Dubois, P. Tozman, M. Venkatesan, J. M. D. Coey, S. Kobe, Hot-compaction of YCo4.8Fe0.2 nanocrystals for metal-bonded magnets, J. Mag. and Magn. Mat. 460 (2018) 401-408.
