Investigation on structure and properties of low-temperature sintered composite ferrites

(Ni0.60Zn0.20Cu0.20)Fe2O4 spinel ferrite powder and Co2Z powder were first synthesized by the self-propagating method. After being mixed with different volume fractions and then sintered at different lower temperatures, a series of novel and dense composites with Co2Z hexaferrite matrix were obtained. X-ray diffraction (XRD) results revealed that the composite ferrites had the diphasic structure of spinel and Z-type hexagonal phases. No chemical reaction between the two constituents during sintering was detected. The composite ferrites have excellent electromagnetic properties in hyperfrequencies more than 1.5 GHz. The mechanisms associated with generating densification and high initial permeability are discussed.