Patent · US Expired

Grooved magnetic substrates and method for producing the same

US4777074A · kind A · utility

3Cited by
7References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 24, 1986
Grant dateOct 11, 1988
Priority date
Expiry dateJul 24, 2006

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/24537
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A grooved magnetic substrate including an alumina film layer having a Knoop hardness of 600 kg/mm.sup.2 to 1200 kg/mm.sup.2 charged in at least one groove formed in a surface of a magnetic substrate. The magnetic substrate may be Mn-Zn or NiZn base ferrite. The alumina film layer is formed by sputtering.

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