Planar High Energy Permanent Magnets

Samarium-cobalt permanent magnets were fabricated by arc plasma spraying in order to evaluate this technique as an economical method for fabricating cobalt-rare earth magnets for advanced traveling wave tubes and crossfield amplifiers. Bar magnets were produced having a coercive force of 6100 oersteds and an energy product of 10.8 million gauss-oersted. The magnetic properties in bar magnets were significantly better in the direction parallel to the spray direction. SmCo5 bar magnets were directly bonded to magnesia-excess spinel substrates and showed no evidence of cracking or warping in the magnet-substrate assembly even after heat treatment. Two 52-bar magnet assemblies were constructed, each consisting of two 26-bar arrays, 1 inch x 8 inch. The bar magnets were magnetized so as to achieve peak axial field strengths of 450 to 500 gauss with a period of 0.6 inch in each assembly. See also report dated Dec 73, AD-771 956.