Magnetic and magnetotransport properties of granular Cu85Fe15 prepared by mechanical alloying

Abstract

The magnetic and magnetotransport properties of granular GussFerS prepared by mechanical alloying have been investigated. The sample was prepared by grinding tine powders of copper and iron in a high energy ball mill. Zero field cooled and field cooled susceptibilities showed a behavior that is typical of a superparamagnet. The blocking temperature TB of 20 K was determined from ac susceptibility. The magnetoresistance reached 5.5% at 4.5 K in a field of 5 T. It was increased to 7.6% after the sample was annealed at 300 "G for 20 min. The hysteresis loop was measured for both magnetization and magnetoresistance. There was a clear correlation between the two. The magnetoresistance is due to the scattering associated with iron nanoparticles present in the samples and its dependence on particle size is discussed.

Magnetoresistance in glass-coated Fe–Ni–Cu microwires

“…1 Fe-Ni-Cu resembles those of GMR granular materials in which magnetic Fe nanoparticles are imbedded in predominately nonmagnetic Cu matrix. 8 The Fe-Ni-Cu microwires are magnetically soft. Both as-cast microwires and those heat treated at 500°C for an hour have typical coercivity of a few Oersted.…”

“…6,7 Granular systems exhibiting GMR have been made applying a variety of sample preparation techniques including thin film deposition and mechanical alloying. 8 In recent years magnetic properties of glasscoated magnetically soft microwires prepared by Taylor's technique have been studied widely. 9 Most recently, kilometer-long glass-coated Fe-Ni-Cu and Fe-Co-Cr microwires have been prepared and their magnetic properties have been studied.…”

Effects of layering and working pressure on magnetic and magnetotransport properties of as sputtered multilayered granular Co/Cu films

“…Different techniques were proposed to prepare granular systems, including melt spinning, evaporation, mechanical alloying and co-sputtering of the immiscible elements composing the heterogeneous alloy [3,[5][6][7]. However, all methods required a subsequent heat treatment of the specimens in order to obtain the particles, dimensions and distribution which give rise to a maximum MR effect.…”

Thermal and Magnetic Properties of Mechanically Alloyed fcc Cu-Fe Supersaturated Solid Solutions

“…20,24) This effect leads to the extension of the fcc cell parameter. 2,25) The effect of the temperature on the lattice expansion was also investigated. At low angles, the in situ X-ray diffraction was made by gradual increase of temperature from 50, 150 to 300 C. As an example, XRD patterns of the 12% Fe compound are presented in Fig.…”