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CoFe(2)O(4)/Fe(3)O(4) nano-composite ceramics were synthesized by Spark Plasma Sintering. The X-ray diffraction patterns show that all samples are composed of CoFe(2)O(4) and Fe(3)O(4) phases when the sintering temperature is below 900 degrees C. It is found that the magnetic properties strongly depend on the sintering temperature. The two-step hysteresis loops for samples sintered below 500 degrees C are observed, but when sintering temperature reaches 500 degrees C, the step disappears, which indicates that the CoFe(2)O(4) and Fe(3)O(4) are well exchange coupled. As the sintering temperature increases from 500 to 800 degrees C, the results of X-ray diffractometer indicate the constriction of crystalline regions due to the ion diffusion at the interfaces of CoFe(2)O(4)/Fe(3)O(4) phases, which have great impact on the magnetic properties. (C) 2011 Elsevier B. V. All rights reserved.