Patent · US Expired

Magnetic disc with carbon protective layer having regions differing in hardness

US5824387A · kind A · utility

28Cited by
11References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 8, 1996
Grant dateOct 20, 1998
Priority date
Expiry dateAug 8, 2016

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/30
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A magnetic disc for use in a disc drive data storage system is disclosed. The magnetic disc includes a layer of magnetic material deposited on a substrate and a carbon overcoat layer deposited on the layer of magnetic material. The carbon overcoat layer has a first hardness over a contact start-stop region of the disc. The carbon overcoat layer has a second hardness over a data storage region of the disc. The second hardness is softer than the first hardness and than a hardness of a diamond like coating on an associated magnetic head so that disc asperities in the data storage region of the carbon overcoat layer will wear upon impact with the magnetic head.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.