| As a non-equilibrium technique, mechanical alloying was first used to prepare oxide dispersion strengthened in Ni-based superalloys in the year 70' of the 20th century. It has received a considerable attention from physicists and metallurgists. Its specific feature is the repeating deformation, fracture and cold welding during the collision between the balls and powder particles, leading to the final steady state of alloys. At the same time the high intensity of stain and defects are introduced in the materials by high energy of ball milling. Thus its thermodynamic and kinetic condition are different from the other solid state reaction. It is characterized by a competition between the thermodynamic driven decomposition and the mechanical driven alloying process. Over the past few years, mechanical alloying has shown to be a powerful technique to synthesize a great variety of nanocrystalline, amorphous, intermetallics, supersaturated solid solution and composite materials. However the properties of such materials and the mechanism of mechanical alloying are not yet clear. Therefore author has prepared and investigated the supersaturated solid solution of Fe-C and Fe-Ni-C. It was hoped to extend the solubility of carbon in bcc and fcc structures by mechanical alloying process. On the other hand the studies on the structural and magnetic properties of Fe-C and Fe-Ni-C would be helpful to develop the theory concerning the magnetic properties of transition-metal-metalloid alloys. It is of prime interest in materials research because of their impact on both theoretical studies and industrials application.The remarkable points of this paper could be summarized as follows:I. Supersaturated solid solution Fe1-xCx and (Fe55Ni45)1-xCx were prepared in a wide concentration range (0≤x≤0.9). The microstructure, magnetic and thermal properties of the milled powders were followed by x-ray diffraction, scanning electron...
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