| 摘要 |
PURPOSE:To enable a magnetic disc to be finished forming its maximum surface roughness to 100Angstrom or less, by using a polishing material dust of different grain size properly in the first half and the latter half of polishing the aluminum magnetic disc so that it is continuously polished in a short time. CONSTITUTION:In the first half of polishing, water slurry of acidic or alkaline etchant, containing an alumina abrasive grains of 0.8-3mum mean grain size, is used. Subsequently, only the slurry is switched to water slurry of acidic or alkaline etchant, containing an alumina abrasive grain of 0.3-0.8mum mean grain size, running the same machine to be left as in operation with no exchange of a polishing pad, and polishing of the latter half is performed finishing an aluminum magnetic disc forming its maximum surface roughness to 100Angstrom or less. |
