Patent US4952536A successfully refreshed from Google Patents.
US4952536A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High strength Al2 O3
Assignee: Vibrantz Corp
•
Filing: 1989-02-23
•
Granted: 1990-08-28
•
Expires: 2009-02-23
Abstract
Abstract An extruded and sintered Al 2 O 3 body having high flexural strength is produced by extruding and sintering and extrusion mixture of alpha-Al 2 O 3 powder, an organic dispersing agent, an optional deaeration agent, and a zirconia sol. The zirconia sol is present in a small amount such that upon firing the final ZrO 2 content of the final body is less than 1 weight percent. The sintered alumina body has a uniform distribution of ZrO 2 particles in the size range of 0.1-1.0 microns.
Inventors
- 👤 Jacob Block
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 06:54
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/01; C04B35/10; C04B35/111
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
124 words
A method of producing an extruded Al 2 O 3 body having a high flexural strength comprising the steps of: (a) forming an extrusion mixture of alpha-Al 2 O 3 powder, an organic dispersing agent, up to 2.0wt % of an organic binder, and a zirconia sol, the amount of said sol being such that upon firing, the ZrO 2 is present is the final body in an amount of no more than 1 w/o; (b) extruding the mixture of step (a) to form an extruded body; (c) sintering the extruded body to form a final Al 2 O 3 body containing no more than 1 w/o ZrO 2 having high flexural strength and having a 3 point flexural strength greater than 55,000 psi.
Claim 2
Independent Claim
124 words
A method of producing an extruded Al 2 O 3 body having a high flexural strength comprising the steps of: (a) forming an extrusion mixture of alpha-Al 2 O 3 powder, an organic dispersing agent, up to 2.0wt % of an organic binder, and a zirconia sol, the amount of said sol being such that upon firing, the ZrO 2 is present is the final body in an amount of no more than 1 w/o; (b) extruding the mixture of step (a) to form an extruded body; (c) sintering the extruded body to form a final Al 2 O 3 body containing no more than 1 w/o ZrO 2 having high flexural strength and having a 3 point flexural strength greater than 55,000 psi.
Claim 3
Dependent Claim
18 words
A method according to claim 1, wherein the extrusion mixture of step (a) further contains a deaeration agent.
Claim 4
Dependent Claim
22 words
A method according to claim 1, wherein the organic binder is present in an amount of about 0.5 to 2.0 weight %.
Claim 5
Dependent Claim
20 words
A method according to claim 2, wherein the zirconia sol has particles in the size range of about 5-10 nanometers.
Claim 6
Dependent Claim
29 words
A method according to claim 2, wherein the organic dispersing agent in step (a) is present in an amount of 1 to 2 weight % on an alumina basis.
Claim 7
Dependent Claim
35 words
A method according to claim 2, wherein the zirconia sol in step (a) is present in an amount sufficient to give a final ZrO 2 concentration of 0.25 to 1.0 w/o on an alumina basis.
Claim 8
Dependent Claim
25 words
A method according to claim 2, wherein the deaeration agent in step (a) is present in an amount of 0.1-0.5 w/o on an alumina basis.
Claim 9
Dependent Claim
12 words
A method according to claim 7, wherein the deaeration agent is n-octanol.
Claim 10
Dependent Claim
21 words
A method according to claim 2, wherein the extruded sintered body has a 3 point flexural strength greater than 65,000 psi.
Claim 11
Dependent Claim
21 words
A method according to claim 9, wherein the extruded sintered body has a 3 point flexural strength greater than 73,000 psi.
Claim 12
Dependent Claim
33 words
An alumina body, having a uniform distribution of ZrO 2 particles in the size range of 0.1-1.0 microns and present in an amount equal to no more than 1.0 w/o ZrO 2 .
Claim 13
Dependent Claim
33 words
An alumina body, having a uniform distribution of ZrO 2 particles in the size range of 0.1-1.0 microns and present in an amount equal to no more than 1.0 w/o ZrO 2 .
Claim 14
Dependent Claim
39 words
An extruded and sintered Al 2 O 3 body having present less than 1 w/o ZrO 2 uniformly distributed as particles of a size of 0.1-1 micron and having a 3 point flexural strength of at least 55,000 psi.
Claim 15
Dependent Claim
39 words
An extruded and sintered Al 2 O 3 body having present less than 1 w/o ZrO 2 uniformly distributed as particles of a size of 0.1-1 micron and having a 3 point flexural strength of at least 55,000 psi.
Claim 16
Dependent Claim
24 words
An extruded and sintered Al 2 O 3 body according to claim 12, having a 3 point flexural strength of at least 65,000 psi.
Claim 17
Dependent Claim
134 words
An extruded and sintered Al 2 O 3 body having high flexural strength made by the process of (a) forming an extrusion mixture of alpha-Al 2 O 3 powder, an organic dispersing agent, a deaeration agent, and a zirconia sol, the amount of said sol being such that upon firing, the ZrO 2 is present in the final body in an amount of no more than 1 w/o; (b) extruding the mixture of step (a) to form an extruded body; and (c) sintering the extruded body to form a final Al 2 O 3 body containing no more than 1 w/o ZrO 2 having high flexural strength and having a 3 point flexural strength of at least 55,000 psi, said body having less than 1.0 w/o ZrO 2 where the zirconia is sol derived.
Claim 18
Dependent Claim
134 words
An extruded and sintered Al 2 O 3 body having high flexural strength made by the process of (a) forming an extrusion mixture of alpha-Al 2 O 3 powder, an organic dispersing agent, a deaeration agent, and a zirconia sol, the amount of said sol being such that upon firing, the ZrO 2 is present in the final body in an amount of no more than 1 w/o; (b) extruding the mixture of step (a) to form an extruded body; and (c) sintering the extruded body to form a final Al 2 O 3 body containing no more than 1 w/o ZrO 2 having high flexural strength and having a 3 point flexural strength of at least 55,000 psi, said body having less than 1.0 w/o ZrO 2 where the zirconia is sol derived.
Claim 19
Dependent Claim
27 words
An extruded and sintered Al 2 O 3 body according to claim 14, wherein the extruded body has a 3 point flexural strength greater than 65,000 psi.
Claim 20
Dependent Claim
25 words
An extruded and sintered Al 2 O 3 body according to claim 14, wherein the extrusion mixture of step (a) further contains an organic binder.
References Cited (Backward Citations)
US4028453A
Cited
US4419311A
Cited
US4218253A
Cited
US4316964A
Cited
US4429051A
Cited
US4784812A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-08-27 | 1994-02-26 | 1994-08-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-08-27 | 1998-02-26 | 1998-08-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-08-27 | 2002-02-26 | 2002-08-28 | $7700.00 | Window Closed / Lapsed |