Claims
- 1. A permanent magnet material having a plurality of longitudinally extending ridges on at least one major surface, the distance between two adjacent ones of the ridges being 100 to 300 .mu.m on average.
- 2. A permanent magnet material according to claim 1 wherein the major surface having the ridges has a centerline average roughness (Ra) of 0.05 to 4.5 .mu.m.
- 3. A permanent magnet material according to claim 1 wherein the ridges have an average height of 0.7 to 30 .mu.m.
- 4. A permanent magnet material according to claim 1 which has a thickness with a standard deviation of up to 4 .mu.m as measured at a position.
- 5. The permanent magnet material of claim 1 which is prepared by cooling a molten alloy containing R wherein R is at least one rare earth element inclusive of Y, Fe or Fe and Co, and B, wherein
- said chill roll has an axis, a circumferential surface, and a plurality of circumferentially extending grooves in the circumferential surface, and the distance between two adjacent ones of the grooves at least in a region with which the molten alloy comes in contact is 100 to 300 .mu.m on average in a cross section containing the axis.
Priority Claims (1)
Number |
Date |
Country |
Kind |
4-097023 |
Mar 1992 |
JPX |
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Parent Case Info
This is a Division of application Ser. No. 07/878,523 filed May 5, 1992 now U.S. Pat. No. 5,665,177.
US Referenced Citations (7)
Foreign Referenced Citations (2)
Number |
Date |
Country |
60-9852 |
Jan 1985 |
JPX |
4-28457 |
Jan 1992 |
JPX |
Divisions (1)
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Number |
Date |
Country |
Parent |
878523 |
May 1992 |
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