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 degrees 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 Delta H = 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.