Chemical synthesis of nickel ferrite spinel designed as an insulating bilayer coating on ferromagnetic particles

0450321 - ÚFM 2016 RIV CH eng J - Článek v odborném periodiku
Strečková, M. - Hadraba, Hynek - Bureš, R. - Fáberová, M. - Roupcová, Pavla - Kuběna, Ivo - Medvecký, L. - Girman, V. - Kollár, P. - Füzer, J. - Čižmár, E.
Chemical synthesis of nickel ferrite spinel designed as an insulating bilayer coating on ferromagnetic particles.
Surface and Coatings Technology. Roč. 270, MAY (2015), s. 66-76. ISSN 0257-8972
Grant CEP: GA ČR(CZ) GA14-25246S; GA MŠMT(CZ) ED1.1.00/02.0068
Institucionální podpora: RVO:68081723
Klíčová slova: soft magnetic composite * NiFe2O4 spinel ferrite * coating * precipitation method * focused ion beam
Kód oboru RIV: JG - Hutnictví, kovové materiály
Impakt faktor: 2.139, rok: 2015

Soft magnetic core–shell particles were designed by coating FeSi and permalloy powders with ferrite nanoparticles. The permalloy-type powder particles were prepared by mechanical alloying process of 80 wt% of Ni, 14.7 wt% of Fe, 4.4 wt% of Mo, 0.5 wt% of Mn and 0.3 wt% Si. NiFe2O4 cuboidal nanoparticles were synthesized by the chemical precipitation of hydroxides by alkaline treatment of the dissolved metal in aqueous chloride solution and the same process was used for a deposition of NiFe2O4 nanoparticles on both substrates. The average size of NiFe2O4 nanoparticles, crystallinity and spinel structure were determined by TEM and XRD techniques. The deposited coating was created in a bilayer form. The composition of individual layer was analyzed by XRD and TEM using 100-nm lamella extracted from the coating by focused ion beam. The chemical composition of individual layers was analyzed by EDX analysis. The specific electric resistivity measurement has confirmed a good insulating character of the designed bilayer coating, whereas the prepared core–shell powders and relevant green compacts belong to soft magnetic materials.
Trvalý link: http://hdl.handle.net/11104/0251707