화학공학소재연구정보센터
Inorganic Chemistry, Vol.56, No.8, 4512-4520, 2017
Synthesis of Highly Uniform and Compact Lithium Zinc Ferrite Ceramics via an Efficient Low Temperature Approach
LiZn ferrite ceramics with high saturation magnetization (4 pi M-s) and low ferromagnetic resonance line widths (Delta H) represent a very critical class of material for microwave ferrite devices. Many existing approaches emphasize promotion of the grain growth (average size is 10-50 mu m) of ferrite ceramics to improve the gyromagnetic properties at relatively low sintering temperatures. This paper describes a new strategy for obtaining uniform and compact LiZn ferrite ceramics (average grains size is similar to 2 mu m) with enhanced magnetic performance by suppressing grain growth in great detail. The LiZn ferrites with a formula of Li0.415Zn0.27Mn0.06Ti0.1Fe2.155O4 were prepared by solid reaction routes with two new sintering strategies. Interestingly, results show that uniform, compact, and pure spinel ferrite ceramics were synthesized at a low temperature (similar to 850 degrees C) without obvious grain growth. We also find that a fast second sintering treatment (FSST) can further improve their gyromagnetic properties, such as higher 4 pi M-s and lower Delta H. The two new strategies are facile and efficient for densification of LiZn ferrite ceramics via suppressing grain growth at low temperatures. The sintering strategy reported in this study also provides a referential experience for other ceramics, such as soft magnetism ferrite ceramics or dielectric ceramics.