Nanopowders with superparamagnetic Fe3C particles and their annealing behaviour

0354295 - ÚFM 2011 RIV GB eng J - Článek v odborném periodiku
David, Bohumil - Schneeweiss, Oldřich - Pizúrová, Naděžda - Dumitrache, F. - Fleaca, C. - Alexandrescu, R.
Nanopowders with superparamagnetic Fe3C particles and their annealing behaviour.
Surface and Interface Analysis. Roč. 42, č. 6-7 (2010), s. 699-702. ISSN 0142-2421. E-ISSN 1096-9918.
[European Conference on Applications of Surface and Interface Analysis /13./. Antalya, 18.10.2009-23.10.2009]
Grant CEP: GA MŠMT 1M0512; GA ČR GA202/08/0178
Výzkumný záměr: CEZ:AV0Z20410507
Klíčová slova: Fe3C * nanocomposite * magnetic measurements * Mössbauer spectroscopy * superparamagnetism
Kód oboru RIV: BM - Fyzika pevných látek a magnetismus
Impakt faktor: 1.247, rok: 2010

Two samples of nanopowders containing superparamagnetic Fe3C and Fe3O4/gamma-Fe2O3 particles and carbon black were synthesized by the method of laser-induced homogeneous pyrolysis of gaseous precursors. Both were characterized by XRD, HR-TEM, Mössbauer spectrometry and standard magnetic measurements. The mean crystallite size of Fe3C was 3 nm for the first sample and 10 nm for the second sample. Fe3C phase in both samples exhibited reduced Curie temperature and smeared ferromagnetic-paramagnetic transition. After annealing of the samples at 800°C for 30min the Curie temperature of the recrystallized Fe3C phase in both samples was 214°C (standard bulk value).
Trvalý link: http://hdl.handle.net/11104/0193332