Investigation of brazing techniques for ferrimagnetic materials: R W Buck et al, Rep SEDT-NJ-2769-0202-5; AD-630700, Jan 1966 (Sperry Rand Corp Gainesville, Fla)

Abstract

Abstract : The following two vapor deposition metalizing techniques were developed for metalizing ferrimagnetic materials: (1) Evaporating approximately 6000 Angstrom units of iron, (2) Sputtering approximately 5000 Angstrom units of nickel. It was advantageous to electrodeposit about 0.0001 inch nickel on the vapor deposited films. Nickel ferrite and yttrium iron garnet toroids were fabricated and brazed to Kovar, copper and titanium mating members using a vacuum brazing furnace equipped with an induction coil. The parts to be brazed were placed inside a box-like nickel container which, in turn, was placed in the induction coil. Incusil 15 and copper-silver eutectic braze alloys were used. Relatively strain-free brazes were made between ferrimagnetic materials and both copper and titanium. Strain could not be eliminated when brazing to Kovar. No significant changes in either saturation magnetism or linewidth as a result of the brazing operation were observed. An increase in dielectric loss tangent was observed when nickel ferrite was metalized with evaporated iron. No changes in dielectric loss tangent were observed when sputtered nickel films were used as metalizing. (Author)