US4414282A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Glass ceramic seals to inconel
Assignee: United States Department of Energy
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Filing: 1982-04-19
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Granted: 1983-11-08
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Expires: 2002-04-19
Abstract
Abstract A glass ceramic composition prepared by subjecting a glass composition comprising, by weight, 65-80% SiO 2 , 8-16%, Li 2 O, 2-8% , Al 2 O 3 , 1-8% K 2 O, 1-5% P 2 O 5 and 1.5-7% B 2 O 3 , to the following processing steps of heating the glass composition to a temperature sufficient to crystallize lithium metasilicate therein, holding the glass composition at a temperature and for a time period sufficient to dissolve the lithium metasilicate therein thereby creating cristobalite nucleii, cooling the glass composition and maintaining the composition at a temperature and for a time period sufficient to recrystallize lithium metasilicate therein, and thermally treating the glass composition at a temperature and for a time period sufficient to cause growth of cristobalite and further crystallization of lithium metasilicate producing a glass ceramic composition having a specific thermal expansion coefficient and products containing said composition.
Inventors
- 👤 Howard L. McCollister
- 👤 Scott T. Reed
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 16:30
CPC Classifications
C; C03; C03C; C03C10/00; C03C27/00; C03C27/04; C03C27/042; C03C27/046
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
147 words
A glass ceramic composition prepared by subjecting a glass composition comprising, by weight, 65-80% SiO 2 , 8-16% Li 2 O, 2-8% Al 2 O 3 , 1-8% K 2 O, 1-5% P 2 O 5 and 1.5-7% B 2 O 3 , to the following processing steps: a. heating the glass composition to a temperature sufficient to crystallize lithium metasilicate therein; b. holding the glass composition at a temperature and for a time period sufficient to dissolve the lithium metasilicate therein thereby creating cristobalite nucleii; c. cooling the glass composition and maintaining the composition at a temperature and for a time period sufficient to recrystallize lithium metasilicate therein; and d. thermally treating the glass composition at a temperature and for a time period sufficient to cause growth of cristobalite and further crystallization of lithium metasilicate producing a glass ceramic composition having a specific thermal expansion coefficient.
Claim 2
Dependent Claim
147 words
A glass ceramic composition prepared by subjecting a glass composition comprising, by weight, 65-80% SiO 2 , 8-16% Li 2 O, 2-8% Al 2 O 3 , 1-8% K 2 O, 1-5% P 2 O 5 and 1.5-7% B 2 O 3 , to the following processing steps: a. heating the glass composition to a temperature sufficient to crystallize lithium metasilicate therein; b. holding the glass composition at a temperature and for a time period sufficient to dissolve the lithium metasilicate therein thereby creating cristobalite nucleii; c. cooling the glass composition and maintaining the composition at a temperature and for a time period sufficient to recrystallize lithium metasilicate therein; and d. thermally treating the glass composition at a temperature and for a time period sufficient to cause growth of cristobalite and further crystallization of lithium metasilicate producing a glass ceramic composition having a specific thermal expansion coefficient.
Claim 3
Dependent Claim
19 words
The glass ceramic composition as recited in claim 1, having a thermal expansion coefficient α of 120-160×10 -7 /°C.
Claim 4
Dependent Claim
50 words
The glass ceramic composition as recited in claim 1, in which the composition of the sealing glass is, by weight, 70-75% SiO 2 , 10-14% Li 2 O, 4-6% Al 2 O 3 , 3-6% K 2 O, 2-4% P 2 O 5 and 2-5% B 2 O 3 .
Claim 5
Dependent Claim
50 words
The glass ceramic composition as recited in claim 1, in which the composition of the sealing glass is, by weight, 71.7% SiO 2 , 12.6% Li 2 O, 5.1% Al 2 O 3 , 4.9% K 2 O, 2.5% P 2 O 5 and 3.2% B 2 O 5 .
Claim 6
Dependent Claim
93 words
The glass ceramic composition as recited in claim 1, wherein the heating of step (a) is conducted at a temerature up to about 1000° C., the holding temperature of step (b) is 950° to 1050° C. and the holding time is 5 to 60 minutes, the composition is cooled to a temperature of 600° to 700° C. and held at said temperature for 10 to 120 minutes in step (c) and wherein the thermal treatment of step (d) is conducted at 775° to 850° C. for a time of 10 to 120 minutes.
Claim 7
Dependent Claim
50 words
The glass ceramic composition as recited in claim 5, in which the composition of the sealing glass is, by weight, 70-75% SiO 2 , 10-14% Li 2 O, 4-6% Al 2 O 3 , 3-6% K 2 O, 2-4% P 2 O 5 and 2-5% B 2 O 3 .
Claim 8
Dependent Claim
50 words
The glass ceramic composition as recited in claim 5, in which the composition of the sealing glass is, by weight, 71.7% SiO 2 , 12.6% Li 2 O, 5.1% Al 2 O 3 , 4.9% K 2 O, 2.5% P 2 O 5 and 3.2% B 2 O 3 .
Claim 9
Dependent Claim
187 words
A process for forming a seal between a glass having a thermal expansion coefficient α of 120-160×10 -7 /°C. and a nickel base alloy having substantially the same thermal expansion coefficient, comprising the steps of: 1. applying a glass having a composition, by weight, of 65-80% SiO 2 , 8-16% Li 2 O, 2-8% Al 2 O 3 , 1-8% K 2 O, 1-5% P 2 O 5 and 1.5-7% B 2 O 3 to the nickel base alloy, and subjecting the glass to the following processing steps: a. heating the glass composition to a temperature sufficient to crystallize lithium metasilicate therein; b. holding the glass composition at a temperature and for a time period sufficient to dissolve the lithium metasilicate therein thereby creating cristobalite nucleii; c. cooling the glass composition and maintaining the composition at a temperature and for a time period sufficient to recrystallize lithium metasilicate therein; and d. thermally treating the glass composition at a temperature and for a time period sufficient to cause growth of cristobalite and further crystallization of lithium metasilicate producing a glass ceramic composition having a specific thermal expansion coefficient.
Claim 10
Dependent Claim
187 words
A process for forming a seal between a glass having a thermal expansion coefficient α of 120-160×10 -7 /°C. and a nickel base alloy having substantially the same thermal expansion coefficient, comprising the steps of: 1. applying a glass having a composition, by weight, of 65-80% SiO 2 , 8-16% Li 2 O, 2-8% Al 2 O 3 , 1-8% K 2 O, 1-5% P 2 O 5 and 1.5-7% B 2 O 3 to the nickel base alloy, and subjecting the glass to the following processing steps: a. heating the glass composition to a temperature sufficient to crystallize lithium metasilicate therein; b. holding the glass composition at a temperature and for a time period sufficient to dissolve the lithium metasilicate therein thereby creating cristobalite nucleii; c. cooling the glass composition and maintaining the composition at a temperature and for a time period sufficient to recrystallize lithium metasilicate therein; and d. thermally treating the glass composition at a temperature and for a time period sufficient to cause growth of cristobalite and further crystallization of lithium metasilicate producing a glass ceramic composition having a specific thermal expansion coefficient.
Claim 11
Dependent Claim
48 words
The process as recited in claim 8, in which the composition of the molten glass is, by weight, 70-75% SiO 2 , 10-14% Li 2 O, 4-6% Al 2 O 3 , 3-6% K 2 O, 2-4% P 2 O 5 and 2-5% B 2 O 3 .
Claim 12
Dependent Claim
48 words
The process as recited in claim 8, in which the composition of the molten glass is, by weight, 70-75% SiO 2 , 12.6% Li 2 O, 5.1% Al 2 O 3 , 4.9% K 2 O, 2.5% P 2 O 5 and 3.2% B 2 O 3 .
Claim 13
Dependent Claim
9 words
A product produced by the process of claim 8.
Claim 14
Dependent Claim
9 words
A product produced by the process of claim 9.
Claim 15
Dependent Claim
9 words
A product produced by the process of claim 10.
Claim 16
Dependent Claim
10 words
An electrical header produced by the process of claim 8.
Claim 17
Dependent Claim
10 words
An electrical header produced by the process of claim 9.
Claim 18
Dependent Claim
10 words
An electrical header produced by the process of claim 10.
Claim 19
Dependent Claim
91 words
The process as recited in claim 8 wherein the heating of step (a) is conducted at a temperature up to about 1000° C., the holding temperature of step (b) is 950° to 1050° C. and the holding time is 5 to 60 minutes, the composition is cooled to a temperature of 600° to 700° C. and held at said temperature for 10 to 120 minutes in step (c) and wherein the thermal treatment of step (d) is conducted at 775° to 850° C. for a time of 10 to 120 minutes.
Claim 20
Dependent Claim
48 words
The process as recited in claim 17, in which the composition of the molten glass is, by weight, 70-75% SiO 2 , 10-14% Li 2 O, 4-6% Al 2 O 3 , 3-6% K 2 O, 2-4% P 2 O 5 and 2-5% B 2 O 3 .
Claim 21
Dependent Claim
48 words
The process as recited in claim 17, in which the composition of the molten glass is, by weight, 71.7% SiO 2 , 12.6% Li 2 O, 5.1% Al 2 O 3 , 4.9% K 2 O, 2.5% P 2 O 5 and 3.2% B 2 O 3 .
Claim 22
Dependent Claim
10 words
A product produced by the process recited by claim 17.
Claim 23
Dependent Claim
10 words
A product produced by the process recited by claim 18.
Claim 24
Dependent Claim
10 words
A product produced by the process recited by claim 19.
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) | 1986-11-07 | 1987-05-09 | 1987-11-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-11-07 | 1991-05-09 | 1991-11-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-11-07 | 1995-05-09 | 1995-11-08 | $7700.00 | Window Closed / Lapsed |