MAGNETIC CORE FOR USE IN WEAK MAGNETIC FIELDS AND METHOD FOR PRODUCTION THEREOF Russian patent published in 1994 - IPC

FIELD: metallurgy. SUBSTANCE: metallic-tape core is made of an amorphous cobalt-base alloy containing (in atomic % ): iron 2-5; Si 10-19; B 9-15; one or several components from the group of titan, vanadium, chromium, manganese, nickel, zirconium, columbium, molybdenum, ruthenium, hafnium, tantalum, tungsten 2-5; with Si and B accounting for 25-30 atomic percent. To attain the highest initial magnetic permeability, the optimum ratio of silicon content to aggregate value of silicon and boron content lays in the range of 0.55-0.60. The most effective transition metal are chromium, molybdenum, and tungsten: as they are oxidizing, an oxide layer is being deposited on the metallic tape protecting the rest of the metal against oxidation. The method includes production of tape of amorphous alloy, coiling the tape into a core, and air roasting of the core. The roasting temperature is 100-150 C below the solidification temperature, the roasting duration is 1-100 minutes, heating rate 1-20 C per minute. EFFECT: improved quality of the alloy, increased initial permeability. 9 cl, 4 tbl