Structural, morphological and magnetic properties of low temperature sintered LiZnTiBi ferrites

Interest in enhancing magnetic performances of low-sintered ceramic materials by co-doping of oxide nanoparticle and low-melting glass has thrived. Usually this process includes performance enhancement of ceramic attributed to grain growth and deterioration caused by excess additives. Here, we study the grain growth and magnetic properties of Bi-substituted LiZnTi (LiZnTiBi) ferrites doped with various Al ₂O ₃-modified ZnO-B ₂O ₃-SiO ₂ (Al-ZBS) glass additives. XRD patterns indicate that the Al-ZBS glass has no effect on lattice constant of ferrite, which means that the Al-ZBS glasss is only existed in grain boundary. SEM results indicate that the LiZnTiBi ferrites has two changes due to the interaction between substituted of Bi ₂O ₃ and doping of Al-ZBS glasses. Firstly, grain growth of the ferrite is dominant and its relative density gradually increases when contents of Al-ZBS glass (x) is less than 0.10. Moreover, the grain growth of the ferrite is suppressed because of competition between the two additives when value of x more than 0.10. Finally, one kind of LiZnTiBi ferrite (x = 0.10) with large average grains size (∼8.11 µm) and good magnetic properties (4πM _s =3747.3 Gs, H _c=165.7 A/m and B _s =324.9 mT) is obtained at ∼900 oC.