Nanostructured spinel(Ni_(0.2)Zn_(0.6)Cu_(0.2)Fe_2O_4) powders were fabricated by a citrate precursor sol-gel method.The original particle size was dominated by different calcining temperature.The nanocrystal powders can be sintered by different sintering methods under a low temperature(≤950℃).The sintering behavior,microstructures and electromagnetic properties of ferrite ceramics were investigated by X-ray diffractometer(XRD),transmission electron microscope(TEM),scanning electron microscope(SEM) and meas...