Claims
- 1. A method of producing a cast alloy, comprising:
- feeding a melt onto a rotary casting roll, the melt comprising from 27 to 34% by weight of at least one element selected from the group consisting of the rare earth elements (R) and yttrium, from 0.7 to 1.4% by weight of boron, with the balance being essentially iron, and optionally other transition elements; cooling the melt in a temperature range of from melting point to 1000.degree. C. at a cooling rate of 300.degree. C. per second or more; and
- further cooling in a temperature range of from 800.degree. C. to 600.degree. C. at a cooling rate of 0.80.degree. C./second or less.
- 2. A method according to claim 1, wherein the cooling rate in the temperature range of from melting point to 1000.degree. C. is 500.degree. C. per second or more, and, further the cooling rate in the temperature range of from 800.degree. C. to 600.degree. C. is 0.75.degree. C. per second or less.
- 3. A method for producing a magnet, comprising:
- crushing and pulyerizing a cast alloy into powder;
- compacting the powder under a magnetic field; and
- sintering the compacted power,
- wherein the cast alloy is obtained by:
- feeding a melt onto a rotary casting roll, the melt comprising from 27 to 34% by weight of at least one element selected from the group consisting of the rare earth elements (R) and yttrium, from 0.7 to 1.4% by weight of boron, with the balance being essentially iron, and optionally other transition elements;
- cooling the melt in a temperature range of from melting point to 1000.degree. C. at a cooling rate of 300.degree. C. per second or more; and
- further cooling in a temperature range of from 800.degree. C. to 600.degree. C. at a cooling rate of 0.80.degree. C./second or less.
- 4. A method for producing a magnet, comprising:
- crushing and pulyerizing a cast alloy into a first powder;
- mixing the first powder with a second powder which contains mainly iron and rare earth elements in an amount greater than the first powder;
- compacting the powder mixture under magnetic field; and then
- sintering the compacted powder mixture;
- wherein the cast alloy is obtained by:
- feeding a melt onto a rotary casting roll, the melt comprising from 27 to 34% by weight of at least one element selected from the group consisting of the rare earth elements (R) and yttrium, from 0.7 to 1.4% by weight of boron, with the balance being essentially iron, and optionally other transition elements;
- cooling the melt in a temperature range of from melting point to 1000.degree. C. at a cooling rate of 300.degree. C. per second or more; and
- further cooling in a temperature range of from 800.degree. C. to 600.degree. C. at a cooling rate of 1.degree. C./second or less.
Priority Claims (1)
Number |
Date |
Country |
Kind |
8-113085 |
Apr 1996 |
JPX |
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Parent Case Info
This application is a division of prior application Ser. No. 08/838,784 filed Apr. 10, 1997.
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Divisions (1)
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Number |
Date |
Country |
Parent |
838784 |
Apr 1997 |
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