Microwave absorptive behavior ofnanocrystalline Ba3Co1.3Zn0.3Cu0.4Fe24O41 powder

摘要

In the present work, Cu2+ and Zn2+ ions were incorporated into the structure of Ba3Co2Fe24O41, in order to obtain the Ba3Co1.3Zn0.3Cu0.4Fe24O41 structure, by the sol-gel precursor method in N2 inert atmosphere. The magnetization curves of Ba3Co1.3Zn0.3Cu0.4Fe24O41 hexaferrite nanopowders were analyzed as a function of temperature, to evaluate the super-paramagnetic (SPM) behavior and its effect on the microwave absorption measurements. The permittivity (ε) and permeability (μ) values were obtained by using the transmission/reflection (T/R) method in a waveguide to evaluate the microwave absorption properties at S and X-Ku bands, for radar absorber material (RAM) application. The partial substitu-tion of Co for Zn and Cu ions and the superpara-magnetic contribution improved the ceramics′ magnetic permeability, resulting in a microwave absorption greater than 90.0 % (reflectivity ≤ -10 dB) at 10.0-12.5 GHz and 13.0-16.0 GHz, with 2.5 and 2.0 mm thick, respectively.