发明名称 |
Disk substrate for a perpendicular magnetic recording medium and a perpendicular magnetic recording medium using the substrate |
摘要 |
A disk substrate for a perpendicular magnetic recording medium is, disclosed. The substrate exhibits sufficient productivity, serves the function of a soft magnetic backing layer of the perpendicular magnetic recording medium, and scarcely generates noise. A perpendicular magnetic recording medium using such a substrate also is disclosed. The disk substrate comprises at least a soft magnetic underlayer formed on a nonmagnetic base plate by means of an electroless plating method. The thermal expansion coefficient of the soft magnetic underlayer is larger than a thermal expansion coefficient of the nonmagnetic disk-shaped base plate. A saturation magnetostriction constant mus satisfies a relation lambdas>=-1x10<SUP>-5</SUP>.
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申请公布号 |
US2005238929(A1) |
申请公布日期 |
2005.10.27 |
申请号 |
US20050104274 |
申请日期 |
2005.04.12 |
申请人 |
FUJI ELECTRIC DEVICE |
发明人 |
UWAZUMI HIROYUKI;TEI YOUICHI;KAINUMA KENGO;HIGUCHI KAZUHITO;ISO AKIRA;KURIHARA HAJIME |
分类号 |
G11B5/667;C23C18/50;G11B5/64;G11B5/65;G11B5/66;G11B5/72;G11B5/73;G11B5/738;(IPC1-7):G11B5/64 |
主分类号 |
G11B5/667 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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