US4035162A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fused abrasive grains consisting essentially of corundum, zirconia and R2 O3
Assignee: Corning Glass Works
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Filing: 1975-11-03
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Granted: 1977-07-12
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Expires: 1995-11-03
Abstract
Abstract Fused abrasive grain consists essentially of: (1) crystalline phases of corundum and zirconia, with an average crystallite size smaller than 300 microns and at least in part being an eutectic matrix and (2) analytically by weight, about 44 to 91% (preferably 44 to 80%) Al 2 O 3 , about 5 to 50% (preferably 17.6 to 50%) ZrO 2 to 0.1 to 12% (preferably 0.2 to 5%) R 2 O 3 wherein R is at least one metal selected from vanadium, chromium, manganese and cobalt, the percentage of R 2 O 3 is based on all R metal content calculated as R 2 O 3 , and the balance, if any, being incidental impurities not exceeding 2%. The R metal content is present as oxide in solid solution within the corundum, as random particles of aluminate phase and/or as small particles of the R metal scattered throughout the grain, depending upon the relative oxidizing-reducing ambient conditions during melting. Melted raw material is formed, directly or indirectly, into grain of appropriate particle sizes for use in abrasive articles such as grinding wheels, coated abrasive products and the like.
Inventors
- 👤 Jack A. Brothers
- 👤 Robert C. Doman
- 👤 Robert N. McNally
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 11:57
CPC Classifications
C; C09; C09K; C09K3/00; C09K3/14; C09K3/1409; C09K3/1427
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
107 words
A fused abrasive grain consisting essentially of (a) the crystalline phases of corundum and zirconia with an average crystallite size smaller than 300 microns and at least in part being an eutectic matrix, and (b) analytically by weight, about 44 to 91% Al 2 O 3 , about 5 to 50% ZrO 2 , 0.1 to 12% R 2 O 3 wherein R is at least one metal selected from vanadium, chromium, manganese and cobalt, the percentage of R 2 O 3 is based on all R metal content calculated as R 2 O 3 , and the balance, if any, being incidental impurities not exceeding 2%.
Claim 2
Dependent Claim
107 words
A fused abrasive grain consisting essentially of (a) the crystalline phases of corundum and zirconia with an average crystallite size smaller than 300 microns and at least in part being an eutectic matrix, and (b) analytically by weight, about 44 to 91% Al 2 O 3 , about 5 to 50% ZrO 2 , 0.1 to 12% R 2 O 3 wherein R is at least one metal selected from vanadium, chromium, manganese and cobalt, the percentage of R 2 O 3 is based on all R metal content calculated as R 2 O 3 , and the balance, if any, being incidental impurities not exceeding 2%.
Claim 3
Dependent Claim
27 words
The abrasive grain of claim 1 wherein, analytically by weight, Al 2 O 3 does not exceed about 80% and ZrO 2 is at least about 17.6%.
Claim 4
Dependent Claim
19 words
The abrasive grain of claim 2 wherein, analytically by weight, R 2 O 3 does not exceed about 5%.
Claim 5
Dependent Claim
20 words
The abrasive grain of claim 1 wherein the crystalline corundum phase contains R 2 O 3 in solid solution therein.
Claim 6
Dependent Claim
55 words
The abrasive grain of claim 1 further containing at least one additional crystalline phase selected from: (a) R metal in the form of randomly scattered particles among the crystalline phases of corundum and zirconia, and (b) an aluminate containing R metal in the form of random particles among the crystalline phases of corundum and zirconia.
Claim 7
Dependent Claim
13 words
The abrasive grain of claim 1 wherein the selected R metal is chromium.
Claim 8
Dependent Claim
19 words
The abrasive grain of claim 6 wherein, analytically by weight, the Cr 2 O 3 is 0.2 to 3%.
Claim 9
Dependent Claim
29 words
The abrasive grain of claim 15 wherein, analytically by weight, the Al 2 O 3 is about 63 to 75% and the ZrO 2 is about 24 to 35%.
Claim 10
Dependent Claim
13 words
The abrasive grain of claim 1 wherein the selected R metal is manganese.
Claim 11
Dependent Claim
24 words
The abrasive grain of claim 9 wherein, analytically by weight, the oxide of manganese considered as Mn 2 O 3 is 0.5 to 5%.
Claim 12
Dependent Claim
38 words
An abrasive article comprising a coacting combination of abrasive grain and bonding material therefor, said abrasive grain being the fused abrasive grain of claim 1, and said bonding material being selected from organic polymer and inorganic bonding agents.
Claim 13
Dependent Claim
39 words
A grinding wheel comprising a coacting combination of abrasive grain and bonding material therefor, said abrasive grain being the fused abrasive grain of claim 1, and said bonding material being selected from organic polymer and vitrified silicate bonding agents.
Claim 14
Dependent Claim
35 words
A grinding wheel comprising a coacting combination of abrasive grain and bonding material therefor, said abrasive grain being the fused abrasive grain of claim 8, and said bonding material being an organic resin bonding agent.
Claim 15
Dependent Claim
31 words
A coated abrasive article comprising a coacting combination of a flexible backing and abrasive grain attached thereto by an adhesive, said abrasive grain being the fused abrasive grain of claim 1.
Claim 16
Dependent Claim
27 words
The abrasive grain of claim 7 wherein, analytically by weight, Al 2 O 3 does not exceed about 80% and ZrO 2 is at least about 17.6%.
Claim 17
Dependent Claim
27 words
The abrasive grain of claim 10 wherein, analytically by weight, Al 2 O 3 does not exceed about 80% and ZrO 2 is at least about 17.6%.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-07-11 | 1981-01-10 | 1981-07-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-07-11 | 1985-01-10 | 1985-07-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-07-11 | 1989-01-10 | 1989-07-12 | $7700.00 | Window Closed / Lapsed |