Structural and magnetic properties of plate-like W-type barium ferrites synthesized with a combination method of molten salt and sol-gel

Plate-like W-type barium ferrites (BaCoZnFe₁₆O₂₇) were prepared by using a combined method of molten salt and a sol-gel process. Pure plate-like W-type barium ferrite with large size about 25 μm and high aspect ratio (diameter/thickness) of ∼35 was obtained at a sintering temperature of 1200 C. Morphology, phase evolution and static properties of the samples sintered at different temperatures (800-1200 C) and dynamic magnetic properties of their composites with silicon resin were investigated by using SEM, XRD, VSM and VNA. It was found that the saturation magnetization M _s increased with increasing sintering temperature, whereas the coercivity H_c decreased. Silicon resin composites filled with 45 vol% of the plate-like BaCoZnFe₁₆O₂₇ particles sintered at 1200 C exhibited promising microwave attenuation properties.