Patent US4119500A successfully refreshed from Google Patents.
US4119500A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for eliminating magnetism of synthetic diamond grains
Assignee: Individual
•
Filing: 1977-07-20
•
Granted: 1978-10-10
•
Expires: 1997-07-20
Abstract
Abstract A process for thermally treating synthetic diamond grains to eliminate magnetism thereof and a diamond grain product obtained by the process, which is suitable for manufacturing electrodeposited diamond tools.
Inventors
- 👤 Hiroshi Ishizuka
- 👤 Kazuo Suzuki
- 👤 Shinichi Tamon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 13:32
CPC Classifications
C; C09; C09K; C09K3/00; C09K3/14; C09K3/1409
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
94 words
A process for producing synthetic diamond grains for electrodeposited abrasive tools, comprising the steps of heating in an inert gas atmosphere or in a vacuum synthetic diamond grains which have magnetic susceptibility because of ferromagnetic inclusions to a temperature between about 800° and about 1,300° C., cooling the resulting diamond grains to room temperature, subjecting the cooled diamond grains to a milling action to adjust the friability thereof ranging from 30 to 55 weight %/90 sec., and obtaining diamond grains with decreased magnetic susceptibility having a bulk density ranging from 1.75 to 1.90 g/cc.
Claim 2
Dependent Claim
94 words
A process for producing synthetic diamond grains for electrodeposited abrasive tools, comprising the steps of heating in an inert gas atmosphere or in a vacuum synthetic diamond grains which have magnetic susceptibility because of ferromagnetic inclusions to a temperature between about 800° and about 1,300° C., cooling the resulting diamond grains to room temperature, subjecting the cooled diamond grains to a milling action to adjust the friability thereof ranging from 30 to 55 weight %/90 sec., and obtaining diamond grains with decreased magnetic susceptibility having a bulk density ranging from 1.75 to 1.90 g/cc.
Claim 3
Dependent Claim
34 words
A process as claimed in claim 1, further comprising the step of chemically treating the thermally treated diamond grains with an oxidizing agent to remove any graphite layer formed thereon during the heating step.
Claim 4
Dependent Claim
23 words
A process as claimed in claim 2, wherein the oxidizing agent is selected from the group consisting of chromic acid and perchloric acid.
Claim 5
Dependent Claim
100 words
The process of producing electrodeposited synthetic diamond tools comprising the steps of heating in an inert gas atmosphere or in a vacuum synthetic diamond grains which have magnetic susceptibility because of ferromagnetic inclusions to a termperature between about 800° and about 1,300° C., cooling the resulting diamond grains to room temperature, subjecting the cooled diamond grains to a milling action to adjust the friability thereof ranging from 30 to 55 weight %/90 sec., said diamond grains having decreased magnetic susceptibility and having a bulk density ranging from 1.75 to 1.90 g/cc, an electrodepositing said diamond grains on a tool base.
Claim 6
Dependent Claim
100 words
The process of producing electrodeposited synthetic diamond tools comprising the steps of heating in an inert gas atmosphere or in a vacuum synthetic diamond grains which have magnetic susceptibility because of ferromagnetic inclusions to a termperature between about 800° and about 1,300° C., cooling the resulting diamond grains to room temperature, subjecting the cooled diamond grains to a milling action to adjust the friability thereof ranging from 30 to 55 weight %/90 sec., said diamond grains having decreased magnetic susceptibility and having a bulk density ranging from 1.75 to 1.90 g/cc, an electrodepositing said diamond grains on a tool base.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-10-09 | 1982-04-10 | 1982-10-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-10-09 | 1986-04-10 | 1986-10-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-10-09 | 1990-04-10 | 1990-10-10 | $7700.00 | Window Closed / Lapsed |