With the development of various precision-guided weapons, new radars, and detection means, stealth technology and stealth materials are paying more and more attention. Stealth materials have been widely used in aircraft, missiles, ships, UAVs, and other military fields. Barium ferrite (BaFe12O19) is a hexagonal crystalline ferromagnetic oxide that has good chemical stability, corrosion resistance, and uniaxial magnetic crystal energy anisotropy. The easy magnetization axis parallel to the C-axis makes it have a large involuntary force and magnetic energy product, so it has been widely used in the field of stealth technology and electromagnetic shielding. In this paper, pure ferrite barium nanoparticles were prepared by sol-gel self-combustion technique. The reaction mechanism and the critical temperature of the solid-state reaction of the dried gel were studied by TG/differential scanning calorimetry (TG-DTA) and Fourier transform infrared spectroscopy (FT-IR). The structure and properties of barium ferrite were studied by scanning electron microscopy (SEM), vibrating sample magnetometer (VSM), and X-ray diffraction (XRD). The results show that the particle size of the products increases gradually with the increase of calcination temperature and is greater than the critical particle size of a single domain. When the precursor was held at 400℃ for 2h and calcined at 1200℃ for 3h, the maximum particle size of 82.7 nm was obtained, greater than the critical particle size of the single domain. The maximum saturation magnetization of the product was 64.72 emu•g−1 , and the minimum coercivity was 1181.07 Oe•g−1.
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