Patent US4520647A successfully refreshed from Google Patents.
US4520647A
Expired / Lapsed
US
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Surface finishing process
Assignee: International Business Machines Corp
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Filing: 1983-08-31
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Granted: 1985-06-04
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Expires: 2003-08-31
Abstract
Abstract A method for modifying the surface properties of a material which applies a deformational force which exceeds the elastic limit of the material at the surface so that a plastic deformation of the surface occurs without modifying the bulk properties of the material.
Inventors
- 👤 James Economy
- 👤 Anagnostis E. Zachariades
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 21:27
CPC Classifications
B; B24; B24B; B24B39/00; B24B39/06
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
140 words
A method for simultaneously modifying the rough micro surfaces on opposite faces of a recording disk substrate, the rough micro surfaces extending beyond the bulk thickness of the substrate, comprising the steps of: placing the substrate between a pair of rollers, said rollers having a surface finish smoother than the rough micro surfaces of the substrate, the hardness of the surfaces of said rollers exceeding the hardness of the rough micro surfaces to be modified, and applying through said rollers a deformational force to the rough micro surfaces to be modified which exceeds the elastic limit of the rough micro surfaces to be modified to produce plastic deformation thereof, said deformation extending into the rough micro surfaces no greater than approximately four microns, without lessening the bulk thickness of the substrate or otherwise modifying the bulk properties of the substrate.
Claim 2
Independent Claim
140 words
A method for simultaneously modifying the rough micro surfaces on opposite faces of a recording disk substrate, the rough micro surfaces extending beyond the bulk thickness of the substrate, comprising the steps of: placing the substrate between a pair of rollers, said rollers having a surface finish smoother than the rough micro surfaces of the substrate, the hardness of the surfaces of said rollers exceeding the hardness of the rough micro surfaces to be modified, and applying through said rollers a deformational force to the rough micro surfaces to be modified which exceeds the elastic limit of the rough micro surfaces to be modified to produce plastic deformation thereof, said deformation extending into the rough micro surfaces no greater than approximately four microns, without lessening the bulk thickness of the substrate or otherwise modifying the bulk properties of the substrate.
Claim 3
Dependent Claim
25 words
A method in accordance with claim 1 in which said rollers rotate at the same rate as the substrate during application of said deformational force.
References Cited (Backward Citations)
US3839893A
Cited
US4481876A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-06-03 | 1988-12-03 | 1989-06-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-06-03 | 1992-12-03 | 1993-06-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-06-03 | 1996-12-03 | 1997-06-04 | $7700.00 | Window Closed / Lapsed |