| 摘要 |
PURPOSE:To reduce the defects including pinholes and the like, by forming an electroplated layer composed of a Ni-P alloy coat on a magnetic disk substrate made of a nonmagnetic substance. CONSTITUTION:A surface treatment film 2 is formed on both surfaces of a disk 1 made of an aluminum alloy by a zinc substituting process, and a copper electroplated film 3 is formed on the film 2. Then an Ni-P alloy film 4 is formed by an electro plating, and the surface of the film 4 is smoothed by a heat treatment and a mechanical working. After this, an iron oxide film 5 is formed on the film 4 by a sputtering process. |
