US4959332A
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Alumina-zirconia-carbide whisker reinforced cutting tools
Assignee: Kennametal Inc
•
Filing: 1988-11-03
•
Granted: 1990-09-25
•
Expires: 2008-11-03
Abstract
Abstract A metalcutting insert is provided with an alumina based ceramic composition composed of (in volume percent, v/o): about 1.5 to 12.5 silicon carbide whiskers and about 7.5 to 17.5 v/o zirconia. The silicon carbide whiskers and zirconia are substantially homogeneously distributed in an alumina base matrix. Preferably, at least about 7 v/o of the alumina based ceramic composition is tetragonal zirconia.
Inventors
- 👤 Pankaj K. Mehrotra
- 👤 Elizabeth R. Billman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 19:52
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/01; C04B35/10; C04B35/111; C04B35/117; C04B35/119; C04B35/622; C04B35/64; C04B35/645; C04B35/71; C04B35/78; C04B35/80
Claims Analysis
Total Claims: 68
Claim 1
Independent Claim
78 words
A metalcutting insert comprising: a rake face; a flank face; a cutting edge at a juncture of said rake face and said flank face; and said metalcutting insert having an alumina based ceramic composition consisting essentially of about 1.5 to 12.5 v/o silicon carbide whiskers, about 7.5 to 17.5 v/o zirconia, wherein at least about 7 v/o of said composition is tetragonal zirconia, and wherein said silicon carbide whiskers and zirconia are dispsersed in an aluminia based matrix.
Claim 2
Dependent Claim
78 words
A metalcutting insert comprising: a rake face; a flank face; a cutting edge at a juncture of said rake face and said flank face; and said metalcutting insert having an alumina based ceramic composition consisting essentially of about 1.5 to 12.5 v/o silicon carbide whiskers, about 7.5 to 17.5 v/o zirconia, wherein at least about 7 v/o of said composition is tetragonal zirconia, and wherein said silicon carbide whiskers and zirconia are dispsersed in an aluminia based matrix.
Claim 3
Dependent Claim
23 words
The metalcutting insert according to claim 1 wherein said silicon carbide whiskers are present at a level of about 2.5 to 11 v/o.
Claim 4
Dependent Claim
21 words
The metalcutting insert according to claim 2 wherein said zirconia is present at a level of about 9 to 16 v/o.
Claim 5
Dependent Claim
22 words
The metalcutting insert according to claim 3 wherein said tetragonal zirconia is present at a level of at least about 7.5 v/o.
Claim 6
Dependent Claim
22 words
The metalcutting insert according to claim 3 wherein said tetragonal zirconia is present at a level of at least about 8 v/o.
Claim 7
Dependent Claim
23 words
The metalcutting insert according to claim 1 wherein said silicon carbide whiskers are present at a level of about 2.5 to 7.5 v/o.
Claim 8
Dependent Claim
21 words
The metalcutting insert according to claim 6 wherein said zirconia is present at a level of about 9 to 16 v/o.
Claim 9
Dependent Claim
22 words
The metalcutting insert according to claim 7 wherein said tetragonal zirconia is present at a level of at least about 7.5 v/o.
Claim 10
Dependent Claim
22 words
The metalcutting insert according to claim 4 wherein said tetragonal zirconia is present at a level of at least about 8 v/o.
Claim 11
Dependent Claim
21 words
The metalcutting insert according to claim 1 wherein said zirconia is present at a level of about 9 to 16 v/o.
Claim 12
Dependent Claim
22 words
The metalcutting insert according to claim 10 wherein said tetragonal zirconia is present at a level of at least about 7.5 v//o.
Claim 13
Dependent Claim
22 words
The metalcutting insert according to claim 10 wherein said tetragonal zirconia is present at a level of at least about 8 v/o.
Claim 14
Dependent Claim
21 words
The metalcutting insert according to claim 10 wherein said silicon carbide whiskers are present at a level of about 1.5 v/o.
Claim 15
Dependent Claim
21 words
The metalcutting insert according to claim 10 wherein said silicon carbide whiskers are present at a level of about 2.5 v/o.
Claim 16
Dependent Claim
21 words
The metalcutting insert according to claim 1 wherein said silicon carbide whiskers are preset at a level of about 1.5 v/o.
Claim 17
Dependent Claim
21 words
The metalcutting insert according to claim 1 wherein said silicon carbide whiskers are present at a level of about 2.5 v/o.
Claim 18
Dependent Claim
103 words
A metalcutting insert comprising: a rake face; a flank face; a cutting edge at a juncture of said rake face and said flank face; and said metalcutting insert having an alumina based ceramic composition consisting of about 1.5-12.5 v/o silicon carbide whiskers, about 7.5 to 17.5 v/o ZrO 2 , a magnesia addition added at a level of about 0.04 to 1 v/o and Al 2 O 3 forming the remainder except for impurities, wherein at least 7 v/o of said composition is tetragonal zirconia, and wherein said silicon carbide whiskers and said zirconia are dispersed in a matrix formed of said alumina.
Claim 19
Dependent Claim
103 words
A metalcutting insert comprising: a rake face; a flank face; a cutting edge at a juncture of said rake face and said flank face; and said metalcutting insert having an alumina based ceramic composition consisting of about 1.5-12.5 v/o silicon carbide whiskers, about 7.5 to 17.5 v/o ZrO 2 , a magnesia addition added at a level of about 0.04 to 1 v/o and Al 2 O 3 forming the remainder except for impurities, wherein at least 7 v/o of said composition is tetragonal zirconia, and wherein said silicon carbide whiskers and said zirconia are dispersed in a matrix formed of said alumina.
Claim 20
Dependent Claim
23 words
The metalcutting insert according to claim 17 wherein said silicon carbide whiskers are present at a level of about 2.5 to 11 v/o.
Claim 21
Dependent Claim
21 words
The metalcutting insert according to claim 18 wherein said zirconia is present at a level of about 9 to 16 v.o.
Claim 22
Dependent Claim
20 words
The metalcutting insert according to claim 19 wherein said tetragonal zirconia is present at a level of about 7.5 v/o.
Claim 23
Dependent Claim
20 words
The metalcutting insert according to claim 19 wherein said tetragonal zirconia is present at a level of about 8.0 v/o.
Claim 24
Dependent Claim
23 words
The metalcutting insert according to claim 19 wherein said silicon carbide whiskers are present at a level of about 2.5 to 7.5 v/o.
Claim 25
Dependent Claim
21 words
The metalcutting insert according to claim 22 wherein said zirconia is present at a level of about 9 to 16 v/o.
Claim 26
Dependent Claim
20 words
The metalcutting insert according to claim 23 wherein said tetragonal zirconia is present at a level of about 7.5 v/o.
Claim 27
Dependent Claim
21 words
The metalcutting insert according to claim 19 wherein said zirconia is present at a level of about 9 to 16 v/o.
Claim 28
Dependent Claim
20 words
The metalcutting insert according to claim 25 wherein said tetragonal zirconia is present at a level of about 7.5 v/o.
Claim 29
Dependent Claim
20 words
The metalcutting insert according to claim 25 wherein said tetragonal zirconia is present at a level of about 8.0 v/o.
Claim 30
Dependent Claim
21 words
The metalcutting insert according to claim 27 wherein said silicon carbide whiskers are present at a level of about 1.5 v/o.
Claim 31
Dependent Claim
21 words
The metalcutting insert according to claim 25 wherein said silicon carbide whiskers are present at a level of about 2.5 v/o.
Claim 32
Dependent Claim
21 words
The metalcutting insert according to claim 25 wherein said silicon carbide whiskers are present at a level of about 1.5 v/o.
Claim 33
Dependent Claim
23 words
The metalcutting insert according to claim 25 wherein said silicon carbide whiskers are present at a level of about 2.5 to 5 v/o.
Claim 34
Dependent Claim
21 words
The metalcutting insert according to claim 17 wherein said silicon carbide whiskers are present at a level of about 2.5 v/o.
Claim 35
Dependent Claim
21 words
The metalcutting insert according to claim 17 wherein said silicon carbide whiskers are present at a level of about 1.5 v/o.
Claim 36
Dependent Claim
23 words
The metalcutting insert according to claim 17 wherein said silicon carbide whiskers are present at a level of about 2.5 to 5 v/o.
Claim 37
Dependent Claim
113 words
A metalcutting insert comprising: a rake face; a flank face; a cutting edge at a juncture of said rake face and said flank face; said metalcutting insert having an alumina based ceramic composition comprising about 1.5-7.5 v/o silicon carbide whiskers, about 7.5 to 17.5 v/o zirconia, wherein said zirconia includes tetragonal zirconia in an amount effective to provide said cutting edge with a lifetime of at least 10 minutes when turning AISI 1045 steel having a hardness of about 190 to 200 BHN under the conditions of 1000 surface feet/minute, 0.025 inch/revolution and 0.0100 inch depth of cut, and wherein said silicon carbide whiskers and zirconia are dispersed in an aluminia based matrix.
Claim 38
Dependent Claim
113 words
A metalcutting insert comprising: a rake face; a flank face; a cutting edge at a juncture of said rake face and said flank face; said metalcutting insert having an alumina based ceramic composition comprising about 1.5-7.5 v/o silicon carbide whiskers, about 7.5 to 17.5 v/o zirconia, wherein said zirconia includes tetragonal zirconia in an amount effective to provide said cutting edge with a lifetime of at least 10 minutes when turning AISI 1045 steel having a hardness of about 190 to 200 BHN under the conditions of 1000 surface feet/minute, 0.025 inch/revolution and 0.0100 inch depth of cut, and wherein said silicon carbide whiskers and zirconia are dispersed in an aluminia based matrix.
Claim 39
Dependent Claim
16 words
The metalcutting insert according to claim 33 wherein said lifetime is at least about 12 minutes.
Claim 40
Dependent Claim
21 words
The metalcutting insert according to claim 36 wherein said silicon carbide whiskers are present at a level of about 1.5 v/o.
Claim 41
Dependent Claim
21 words
The metalcutting insert according to claim 36 wherein said silicon carbide whiskers are present at a level of about 2.5 v/o.
Claim 42
Dependent Claim
16 words
The metalcutting insert according to claim 33 wherein said lifetime is at least about 15 minutes.
Claim 43
Dependent Claim
33 words
The metalcutting insert according to claim 39 wherein said alumina based ceramic composition further comprises a magnesia addition added at a level of 0.03 to 3 v/o of said alumina based ceramic composition.
Claim 44
Dependent Claim
23 words
The metalcutting insert according to claim 40 wherein said silicon carbide whiskers are present at a level of about 2.5 to 5 v/o.
Claim 45
Dependent Claim
23 words
The metalcutting insert according to claim 39 wherein said silicon carbide whiskers are present at a level of about 2.5 to 5 v/o.
Claim 46
Dependent Claim
21 words
The metalcutting insert according to claim 39 wherein said silicon carbide whiskers are present at a level of about 1.5 v/o.
Claim 47
Dependent Claim
21 words
The metalcutting insert according to claim 39 wherein said silicon carbide whiskers are present at a level of about 2.5 v/o.
Claim 48
Dependent Claim
23 words
The metalcutting insert according to claim 35 wherein said silicon carbide whiskers are present at a level of about 2.5 to 7.5 v/o.
Claim 49
Dependent Claim
21 words
The metalcutting insert according to claim 45 wherein said zirconia is present at a level of about 9 to 16 v/o.
Claim 50
Dependent Claim
21 words
The metalcutting insert according to claim 35 wherein said zirconia is present at a level of about 9 to 16 v/o.
Claim 51
Dependent Claim
23 words
The metalcutting insert according to claim 47 wherein said silicon carbide whiskers are present at a level of about 2.5 to 5 v/o.
Claim 52
Dependent Claim
33 words
The metalcutting insert according to claim 48 wherein said alumina based ceramic composition further comprises a magnesia addition added at a level of 0.03 to 3 v/o of said alumina based ceramic composition.
Claim 53
Dependent Claim
23 words
The metalcutting insert according to claim 35 wherein said silicon carbide whiskers are present at a level of about 2.5 to 5 v/o.
Claim 54
Dependent Claim
33 words
The metalcutting insert according to claim 50 wherein said alumina based ceramic composition further comprises a magnesia addition added at a level of 0.03 to 3 v/o of said alumina based ceramic composition.
Claim 55
Dependent Claim
33 words
The metalcutting insert according to claim 33 wherein said alumina based ceramic composition further comprises a magnesia addition added at a level of 0.03 to 3 v/o of said alumina based ceramic composition.
Claim 56
Dependent Claim
21 words
The metalcutting insert according to claim 35 wherein said silicon carbide whiskers are present at a level of about 1.5 v/o.
Claim 57
Dependent Claim
21 words
The metalcutting insert according to claim 35 wherein said silicon carbide whiskers are present at a level of about 2.5 v/o.
Claim 58
Dependent Claim
82 words
A metalcutting insert comprising: a rake face; a flank face; a cutting edge at a juncture of said rake face; said metalcutting insert having an alumina based ceramic composition comprising about 1.5 to 37.5 v/o titanium carbide whiskers, and 1.5 to 7.5 v/o silicon carbide whiskers; about 7.5 to 17.5 v/o zirconia; wherein at least about 7 v/o of said composition is tetragonal zirconia; and wherein said titanium carbide whiskers, silicon carbide whiskers and zirconia are dispersed in an alumina based matrix.
Claim 59
Dependent Claim
82 words
A metalcutting insert comprising: a rake face; a flank face; a cutting edge at a juncture of said rake face; said metalcutting insert having an alumina based ceramic composition comprising about 1.5 to 37.5 v/o titanium carbide whiskers, and 1.5 to 7.5 v/o silicon carbide whiskers; about 7.5 to 17.5 v/o zirconia; wherein at least about 7 v/o of said composition is tetragonal zirconia; and wherein said titanium carbide whiskers, silicon carbide whiskers and zirconia are dispersed in an alumina based matrix.
Claim 60
Dependent Claim
25 words
The metalcutting insert according to claim 55 wherein titanium carbide whiskers are present at a level of about 10 to 30 v/o of said composition.
Claim 61
Dependent Claim
14 words
The metalcutting insert according to claim 56 containing at least 8 v/o tetragonal zirconia.
Claim 62
Dependent Claim
14 words
The metalcutting insert according to claim 55 containing at least 7.5 v/o tetragonal zirconia.
Claim 63
Dependent Claim
23 words
The metalcutting insert according to claim 55 wherein said silicon carbide whiskers are present at a level of about 2.5 to 7.5 v/o.
Claim 64
Dependent Claim
21 words
The metalcutting insert according to claim 59 wherein said zirconia is present at a level of about 9 to 16 v/o.
Claim 65
Dependent Claim
21 words
The metalcutting insert according to claim 55 wherein said zirconia is present at a level of about 9 to 16 v/o.
Claim 66
Dependent Claim
23 words
The metalcutting insert according to claim 61 wherein said silicon carbide whiskers are present at a level of about 2.5 to 5 v/o.
Claim 67
Dependent Claim
23 words
The metalcutting insert according to claim 55 wherein said silicon carbide whiskers are present at a level of about 2.5 to 5 v/o.
Claim 68
Dependent Claim
33 words
The metalcutting insert according to claim 55 wherein said alumina based ceramic composition further comprises a magnesia addition added at a level of 0.03 to 3 v/o of said alumina based ceramic composition.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1993-09-24 | 1994-03-26 | 1994-09-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-09-24 | 1998-03-26 | 1998-09-25 | $3760.00 | Window Closed / Lapsed |
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