PURPOSE: To produce a permanent magnet excellent in magnetic properties by repeating, twice, an operation consisting of sealing an ingot of alloy containing rare earth elements, transition elements and B as essential components in a metallic capsule by the use of a lubricant and hot-working the above capsule at specific temp.
CONSTITUTION: An ingot of an alloy containing rare earth elements, transition metals such as Fe, Ni and Co, by atom, 8 to 25%/65 to 90%/and 2 to 10%, respectively, and B is sealed in a capsule made of, e.g. a stainless steel having a melting point higher than that of this alloy by using a lubricant such as BN. This metallic capsule is heated up to 750-1150°C and subjected to hot forging or to hot rolling while constructing the capsule from a width direction, and then the metallic capsule is peeled off. The resulting plural alloy blanks after removal of the metallic capsules are laminated in a plate-thickness direction without the use of the lubricant, which is sealed in a metallic capsule by using the lubricant and subjected to hot forging or to hot rolling at 750 to 1150°C while constraining the capsule again from the width direction. Subsequently, heat treatment is applied to the above at 400 to 700°C to refine the structure of the alloy and then the metallic capsule is peeled off, by which the permanent magnet having an alloy structure excellent in orientational property and also having superior magnetic properties can be produced.
YURI TSUKASA
OKI TSUGUAKI
TAKAHASHI YOICHI
YOSHIDA CHISATO
KANBE AKIFUMI
MIYAGAWA MUTSUHIRO
OKADA MASATOSHI
HASEGAWA TAKESHI
SHIMODA TATSUYA
SEIKO EPSON CORP
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