Synthesis of Nano-Crystalline Magnetite by SHS Route

Author

Ataie, A. ; Kazemzadeh, H. ; Nikkhah-Moshaie, R. ; Ahmed, F.M.

Author_Institution

Sch. of Metall. & Mater. Eng., Univ. of Tehran, Tehran

Volume

45

Issue

6

fYear

2009

fDate

6/1/2009 12:00:00 AM

Firstpage

2496

Lastpage

2498

Abstract

Nano-crystalline magnetite powder has been prepared successfully by self- propagating high-temperature synthesis (SHS) reaction using Fe, Fe₂O₃ and sodium perchlorate as starting materials. The synthesized powder has been subjected to intense milling using a planetary ball mill up to 10 h. The effects of Fe/Fe₂O₃ molar ratio as well as the milling time on the powder particle characteristics were investigated using XRD, SEM, TEM and VSM techniques. XRD results showed that the non-stoichiometric molar ratio (2.5 Fe+0.5 Fe₂O₃) is more favorable to synthesize magnetite phase. The phase composition was not affected significantly by milling process while both mean particle and crystallite size were decreased. Mean crystallite size of magnetite reduced from 90 to 40 nm after 10 h milling. Saturation magnetization (M_s) increased from 47.6 in non-milled sample to 69.6 emu/g in milled sample for 10 h, while the coercivity (H_c) reduced from 365 to 120 Oe after milling.

Keywords

X-ray diffraction; ball milling; coercive force; combustion synthesis; ferrimagnetic materials; high-temperature effects; iron compounds; magnetic particles; magnetic semiconductors; nanoparticles; particle size; scanning electron microscopy; transmission electron microscopy; Fe₃O₄; SEM; TEM; VSM techniques; XRD; ball milling; coercivity; crystallite size; ferrimagnetic materials; nanocrystalline magnetite powder; nonstoichiometric molar ratio; particle size; phase composition; saturation magnetization; self-propagating high-temperature synthesis reaction; Ferrimagnetic materials; materials processing; nanotechnology; soft magnetic materials;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/TMAG.2009.2018671

Filename

4957674