Patent US4852999A successfully refreshed from Google Patents.
US4852999A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cutting tool
Assignee: KENNEMETAL Inc A CORP OF PA
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Filing: 1987-05-28
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Granted: 1989-08-01
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Expires: 2007-05-28
Abstract
Abstract A ceramic composition comprising a polycrystalline alumina matrix having titanium carbide whiskers distributed therein. The composition comprises 50 to 90 volume percent high purity alumina, 10 to 50 volume percent single crystal titanium carbide whiskers, and up to 3 volume percent being the residue of sintering aids.
Inventors
- 👤 Pankaj K. Mehrotra
- 👤 Elizabeth R. Billman
- 👤 Bernard North
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 19:57
CPC Classifications
B; B24; B24D; B24D3/00; B24D3/02; B24D3/04; B24D3/06; C; C04; C04B; C04B35/00; C04B35/01; C04B35/10; C04B35/111; C04B35/71; C04B35/78; C04B35/80
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
51 words
A sintered ceramic composition comprising a polycrystalline alumina matrix having titanium carbide whiskers distributed therein, said composition comprising (a) 50 to 90 volume percent high purity alumina, (b) 10 to 50 volume percent single crystal titanium carbide whiskers, and (c) up to 3 volume percent being the residue of sintering aids.
Claim 2
Dependent Claim
51 words
A sintered ceramic composition comprising a polycrystalline alumina matrix having titanium carbide whiskers distributed therein, said composition comprising (a) 50 to 90 volume percent high purity alumina, (b) 10 to 50 volume percent single crystal titanium carbide whiskers, and (c) up to 3 volume percent being the residue of sintering aids.
Claim 3
Dependent Claim
40 words
The sintered ceramic composition according to claim 1 wherein the high purity alumina is comprised of at least 99 weight percent Al 2 O 3 and the residue of sintering aids comprises up to 1 volume percent ZrO 2 .
Claim 4
Dependent Claim
49 words
The sintered ceramic composition according to claim 2 wherein the average grain size of the high purity alumina matrix is 0.5 to 3 microns and the diameter of the titanium carbide whiskers ranges from 0.25 to 3 microns and the length of the whiskers ranges up to 150 microns.
Claim 5
Dependent Claim
38 words
The sintered ceramic composition according to claim 1 comprising: (a) 65 to 85 volume percent high purity alumina, (b) 15 to 35 volume percent titanium carbide whiskers, and (c) up to 1.5 volume percent residue of sintering aids.
Claim 6
Dependent Claim
38 words
The sintered ceramic composition according to claim 1 comprising: (a) 75 to 85 volume percent high purity alumina (b) 25 to 35 volume percent titanium carbide whiskers, and (c) up to 1.5 volume percent residue of sintering aids.
Claim 7
Dependent Claim
14 words
The sintered ceramic composition according to claim 1 wherein the whiskers are randomly oriented.
Claim 8
Dependent Claim
20 words
The sintered ceramic composition according to claim 1 wherein the whiskers are preferentially oriented in planes perpendicular to one axis.
Claim 9
Dependent Claim
33 words
A sintered ceramic cutting tool insert of a ceramic composition comprised of: 50to 90 volume percent alumina; 10 to 50 volume percent TiC whiskers; and up to 3 volume percent sintering aid residue.
Claim 10
Dependent Claim
33 words
A sintered ceramic cutting tool insert of a ceramic composition comprised of: 50to 90 volume percent alumina; 10 to 50 volume percent TiC whiskers; and up to 3 volume percent sintering aid residue.
Claim 11
Dependent Claim
38 words
The sintered ceramic cutting tool insert according to claim 8 wherein said ceramic composition is comprised of: 65 to 85 volume percent alumina; 15 to 35 volume percent TiC whiskers; and 0.25 to 1.5 residue of sintering aid.
Claim 12
Dependent Claim
40 words
The sintered ceramic cutting tool insert according to claim 8 wherein said ceramic composition is comprised of: 65 to 75 volume percent alumina; 25 to 35 volume percent TiC whiskers; and 0.25 to 1.5 volume percent residue of sintering aid.
Claim 13
Dependent Claim
35 words
A sintered ceramic cutting tool insert of a ceramic composition consisting of: 50 to 90 volume percent alumina; 10 to 50 volume percent TiC whiskers; and up to 3 volume percent residue of sintering aid.
Claim 14
Dependent Claim
35 words
A sintered ceramic cutting tool insert of a ceramic composition consisting of: 50 to 90 volume percent alumina; 10 to 50 volume percent TiC whiskers; and up to 3 volume percent residue of sintering aid.
Claim 15
Dependent Claim
39 words
The sintered ceramic cutting tool insert according to claim 11 wherein said ceramic composition consists of: 65 to 85 volume percent alumina; 15 to 35 volume percent TiC whiskers; and 0.25 to 1.5 volume percent residue of sintering aid.
Claim 16
Dependent Claim
39 words
The sintered ceramic cutting tool insert according to claim 11 wherein said ceramic composition consists of: 65 to 75 volume percent alumina; 25 to 35 volume percent TiC whiskers; and 0.25 to 1.5 volume percent residue of sintering aid.
Claim 17
Dependent Claim
19 words
The sintered ceramic cutting tool according to claim 8 wherein said residue of sintering aid is ZrO 2 .
Claim 18
Dependent Claim
19 words
The sintered ceramic cutting tool according to claim 10 wherein said residue of sintering aid is ZrO 2 .
Claim 19
Dependent Claim
19 words
The sintered ceramic cutting tool according to claim 11 wherein said residue of sintering aid is ZrO 2 .
Claim 20
Dependent Claim
19 words
The sintered ceramic cutting tool according to claim 13 wherein said residue of sintering aid is ZrO 2 .
References Cited (Backward Citations)
US3580708A
Cited
US4543345A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-07-31 | 1993-01-30 | 1993-08-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-07-31 | 1997-01-30 | 1997-08-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-07-31 | 2001-01-30 | 2001-08-01 | $7700.00 | Window Closed / Lapsed |