PURPOSE: To make the production of a permanent magnet alloy having high performance possible in the stage of producing a permanent magnet by sintering, solubilizing and annealing of a powder molding of an R2T17 type intermetallic compd., by subjecting the molding to annealing repeatedly up to specific temps.
CONSTITUTION: An R2T17 type intermetallic compd. (R is Mischmetal, 1 or ≥2 kinds amoung rare earth metals including Y, T is a combination of transition metals consisting essentially of Co, Fe) is produced by melting from raw materials, and the ingot thereof is ground to 4μm average grain sizes. After the powder is pressurized and molded in a magnetic field, the molding is sintered for 2 hours at 1200°C in a vacuum atmosphere. In succession, the sintered molding is subjected to a solubilizing treatment for 6 hours at 1160°C and is then cooled down to a room temp. in Ar. Finally, the molding is subjected to heat treatments consisting of heating for about 1 hour at 800W900°C followed by slow cooling down to about 400°C at least twice as an annealing treatment. The permanent magnet having excellent magnetic characteristics is obtained.
SATOU KAZUYA
TAMURA YOSHIHISA
