Method for forming a drive hole in arc plasma spray fabricated ferrite phasors

摘要

A method for forming a drive wire hole in a ferrite toroid phase shifter adapted to operate in the millimeter frequency range. The ferrite toroid is fabricated by the arc plasma spray process. A slab of boron nitride is initially bonded to the dielectric insert of the ferrite toroid and the ferrite powder is arc plasma sprayed on the composite boron nitride-dielectric structure. The formed ferrite toroid is then annealed, and during the annealing process, the boron nitride slab is completely sublimated to form the required drive wire hole.