Chemico- thermal synthesis of nano-structured cobalt with distinct magnetic property

Document Type: Research Paper

Authors

School of Metallurgy and Materials Engineering, University of Tehran, Tehran.

10.7508/jns.2011.01.002

Abstract

The synthesis of nano- structured cobalt through a controlled chemical process followed by heat treating at various temperatures is studied. The product is characterized by ICP, XRD, FESEM , and TEM, indicating that the as- synthesized particles have an amorphous structure with 1.76 for Co/B ratio, an average size of 50 nm. The transformation of intermediate phases into single phase nano- crystalline metallic cobalt during the heat treatment is investigated by DSC analysis. The mean crystallite size of obtained cobalt was 30 nm. The decrease in coercivity (4344.93A/mf) with the sharp increase in saturation magnetization (1.41×10-4 Am2/kg) presents excellent ferro- magnetic properties for nano- crystallite cobalt.

Keywords


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