Magnetic disk substrate polishing method and polishing pad therefor.

摘要

The disclosure is directed to a method and apparatus for superfinishing magnetic disk substrates (25) using a non-friable polishing pad (10) including a high density polyurethane foam binder in which at least 50% by weight of classified hard particles are retained. Polishing occurs by rotating the pad (10) against the surface (25) to be ultrafinished in the presence of a water soluble liquid vehicle, maintaining a minimum pressure of 0,35 Kgf/cm2 at a rotational speed that achieves the desired aggressiveness of the polishing media. The method and apparatus contemplate both the ultrafinishing of newly prepared substrate disks and the restoring of previously coated disks to a ultrafinished substrate condition without producing substances or conditions toxic to the ecology or the operator.