Low-temperature sintering and ferrimagnetic properties of LiZnTiMn ferrites with Bi2O3–Nb2O5 eutectic mixture

In order to investigate the sintering temperature requirements of low-temperature co-fired ceramics (LTCC) technology, the effects of Bi2O3–Nb2O5 addition on microstructures and magnetic performances of low-temperature sintered Li0.42Zn0.27Ti0.11Mn0.1Fe2.1O4 (LiZnTiMn) ferrites were studied. The microstructure, compactness, and ferromagnetism of samples with different Bi2O3–Nb2O5 contents were measured and analyzed in the sintering temperature 880–920 °C. The results demonstrate that adding an appropriate amount of Bi2O3–Nb2O5 significantly enhances the growth of grains and reduces the abnormal grains, leading to uniform and dense LiZnTiMn ferrite ceramics. The X-ray diffraction and scanning electron microscopy results show that pure spinel phase LiZnTiMn ferrite ceramics were obtained, and proper Bi2O3–Nb2O5 addition could achieve higher densification and better grain growth. Specifically, the performance of the samples doped with 0.5 wt% Bi2O3 and 0.1 wt% Nb2O5 additives was more prominent with the following parameters: Bs = 328.34 mT, Br/Bs = 0.875, Hc = 152.26 A/m, and ΔH = 161.2 Oe. The results indicate that LiZnTiMn ferrite doped with appropriate amounts of Bi2O3–Nb2O5 additives has better gyromagnetic properties and can be well combined with LTCC technology and phased array radar system.