Microwave absorbing characteristics in Co2+ and Al3+ substituted Ba0.5Sr0.5CoxAlxFe12−2xO19 hexagonal ferrite

The Co 2+ and Al 3+ ions substituted M-type hexagonal ferrites with chemical composition Ba 0.5 Sr 0.5 Co x Al x Fe 12−2x O 19 (x = 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0) were synthesized by a standard ceramic method. The prepared samples were characterized using X-ray diffraction in order to check phase purity. The absorber testing device method is adopted to investigate microwave absorption of ferrite compositions as a function of frequency, substitution and thickness from 8.2 to 12.4 GHz. The microwave absorption has been evaluated using the standard model of quarter wavelength mechanism and impedance matching mechanism. The microwave absorption is enhanced with the substitution of Co 2+ and Al 3+ ions in synthesized Ba–Sr hexagonal ferrites. Composition x = 1.0 exhibits good microwave absorber characteristics with 96.94 % absorbed power and −16.4 dB RL at matching frequency and thickness of 11.22 GHz and 2.9 mm respectively.