Paul D. Baba, Gil M. Argentina et al. Fabrication and Properties of Microwave Lithium Ferrites

IEEE Transactions on Magnetics. - 1972. - Vol. 8. - P. 83-94Lithium ferrites are low-cost materials which are attractive for microwave device applications. For a number of years these materials have been prominent in the computer core industry because of excellent temperature performance and the squareness of their hysteresis loops. Previous attempts at exploiting lithium ferrites for microwave applications have met with limited success. Properties which required further improvements
were the dielectric and magnetic loss tangentsa, nisotropy, coercive force, and density.
The microwave lithium ferrites offer a high degree of latitude for tailoring various parameters for special device requirements. However, the optimization of selected properties is sometimes accomplished at the expense of other properties. Although this investigation was directed mainly toward applications for latching devices, lithium ferrites have been altered for use in a variety of devices such as limiters and circulators. The requirements for ferrite materials in latching phasers are reviewed, the compositional factors which result in useful properties are discussed, and performance in circulators and latching phasers is reported.