Fine Particle Li-Ferrite for APS Millimeter-Wave Phase Shifter.

摘要

Powders composed of spheroidal particles 0.5-0.6 micrometer average size have been synthesized by rapidly quenching melts in the system lithium carbonate-boron oxide-iron oxide. The flow characteristics of the powders are adequate to fabricate Li-ferrite ceramic bodies by arc-plasma-spraying (APS) the powders. Post annealing leads to densification and grain growth with concomitant decrease in coercive force and increase in magnetization and remanence. Inversions in x-ray diffraction line intensity disappears with APS and annealing, yielding expected cation distribution. The inadvertent introduction of zinc accounts for the observed inverse relationship between magnetic moment and Curie temperature. The synthetic powder process requires further refinement to improve powder flow characteristics. (Author)