Method of manufacturing a magnetic disk substrate
US5188677A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 21, 1991 |
| Grant date | Feb 23, 1993 |
| Priority date | — |
| Expiry date | Jun 21, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/73919
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method of manufacturing a titanium alloy magnetic disk substrate comprising (a) cold-rolling an alloy plate at a rolling ratio of no less than 30%, the alloy plate comprising 0.5 wt. % to 1.0 wt. % of Mo and containing oxygen, nitrogen and carbon in amounts such that O+2N+0.75C is from 0.03 wt. % to 0.5 wt. % of the titanium alloy, and the balance being Ti, wherein O is the wt. % of oxygen, N is the wt. % of nitrogen and C is the wt. % of C to form a magnetic disk substrate material and then (b) thermal-flattening the magnetic substrate material from step (a) under a condition defined as follows: PA1 500.ltoreq.T.ltoreq.-(150/11).multidot.t+7,850/11 1.ltoreq.t where T represents a thermal-flattening temperature in .degree.C., and t represents a thermal-flattening time in hours.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.