Synthesis of cARBON/Fe-Ni-Cu alloy composite by carbonization of organometallic polymers and their magnetic properties

Carbon/Fe-Ni-Cu alloy composites were synthesized by carbonization of organometallic polymers obtained from ion exchanged chelate resins. The carbonization was performed at 900 °C in a N₂ gas flow. The composition of the Fe-Ni-Cu alloy in a carbon matrix can be controlled by the adjusting solution compositions in the ion exchange process. The carbon obtained from the organometallic polymer was crystallized to a turbostratic structure. X-ray diffraction patterns revealed that the Cu, Fe and Ni elements in the ion exchanged chelate resins were crystallized to a Fe-Ni-Cu alloy after carbonization at 900°C. This result indicates that the formation of the ternary alloy in the carbon matrix is coincident with the crystallization of the well-ordered turbostratic structure of the carbon matrix. The alloy particles with an average size of about 200-700 nm were widely dispersed in the carbon matrix. The saturation magnetization and coercivity of the composites depended on the alloy composition. The saturation magnetization and coercivity of the carbon/Fe_0.52Ni_0.42Cu_0.06 alloy composite were 7.9 emu/g and 167 Oe, respectively.