ISSN:
1662-9752
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Ultrafine magnetic nickel ferrite particles have a significant potential for use inmany applications such as magnetic recording media, ferrofluids, microwaves, catalysis andradar-absorbing coatings [1, 2]. Nickel ferrite powders with a nominal NiFe2O4 compositionwere synthesized by combustion reaction and an evaluation was made of the effect of twodifferent conditions of synthesis on the nanostructural and magnetic characteristics of theresulting powders. Two synthesization routes were studied. The first, NFB, involved thepreparation of the powder using a Pyrex beaker heated directly on a hot plate at 480ºC untilself-ignition occurred. By the second route, NFC, the powder was obtained under the samesynthesization condition as the NFB route, but a vitreous silica basin was used. The resultingpowders were characterized by X-ray diffraction (XRD), nitrogen adsorption by BET andscanning electron microscopy (SEM). The first route, NFB, proved more favorable to obtainpowders with high surface area and, hence, smaller crystalline sizes (5.70 nm) and asuperparamagnetic behavior. The NFC route confirmed the feasibility of obtaining powderswith a crystalline size of 18.00 nm and a magnetic behavior. Saturation magnetization was33.18 emu/g and the coercivity field was 25.63 Oe for powders obtained by the NFC route
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/02/14/transtech_doi~10.4028%252Fwww.scientific.net%252FMSF.530-531.637.pdf
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