title: Particle size dependence on magnetic and electrical properties of (Ni0.8Fe0.2)10C90 granular composites.
abstract: The granular structure and electrical transport behavior of ball milled magnetic permalloy particles and graphite forming (Ni0.8Fe0.2)10C90 granular composites have been reported. Retaining the composite composition to be 90:10 and varying the particle size of permalloy, the electronic transport properties have been carried out down to 4 K under the external applied magnetic field of 50 kOe. All the samples show semiconducting like behavior and positive magnetoresistance (MR) in the temperature range 4-300 K. A strong anisotropic magnetoresistance in these samples has also been observed. The highest 31% longitudinal and 6.8% transverse magnetoresistance values have been observed in 40 hrs ball milled (Ni0.8Fe0.2)10C90 composite. From these studies, we suggest that the magnetic component present in the sample may not be playing a major role in obtaining large positive MR values, which is in deviation with the earlier reports.
authors: Cryogenic Engineering Center, Indian Institute of Technology, Kharagpur 721302, India.
authors: Guruprasad
authors: G
authors: Mandal
authors: V
authors: V
authors: Srinivas
authors: V V
authors: VV
authors: Rao
mesh_terms: D004553:Electric Conductivity; D006108:Graphite / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D008280:Magnetics; D008422:Materials Testing; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D009532:Nickel / Q000737:chemistry*; D010316:Particle Size; D011208:Powders
chemical_list: D011208:Powders; D006108:Graphite; D009532:Nickel; D007501:Iron