Effect of the milling conditions on the formation of nanostructured Fe-Co powders
Abstract
Nanostructured Fe–12Co (wt%) powders were prepared by mechanical alloying in a planetary ball mill. The milling process was carried out at different milling conditions. The obtained powders were characterized by X-ray diffraction, 57Fe Mössbauer spectrometry and magnetic measurements. The low and high speed ball-milling conditions lead to the formation of a single and two-bcc Fe(Co) structure, respectively, having different crystallite sizes, microstrains hyperfine parameters and magnetic properties. The average hyperfine magnetic field values: 〈B〉1 = 34.8 T and 〈B〉2 = 28.2 T of the two-bcc Fe(Co) structure could be attributed to the nanocrystalline grains and to the grain boundaries, respectively. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)