Patent US4704332A successfully refreshed from Google Patents.
US4704332A
Expired / Lapsed
US
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Lightweight fiber reinforced high temperature stable glass-ceramic abradable seal
Assignee: RTX Corp
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Filing: 1982-11-01
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Granted: 1987-11-03
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Expires: 2002-11-01
Abstract
Abstract A composite material suitable for use as an abradable seal is described. The seal comprises a high temperature stable fiber reinforced glass or glass-ceramic matrix base having at least one layer of abradable ceramic material, plasma sprayed or bonded to it. The ceramic abradable layer has a working temperature up to at least 3000° F. (1648° C.) and is oxidatively stable. The abradable seal has particular utility in a gas turbine engine.
Inventors
- 👤 John J. Brennan
- 👤 Richard C. Novak
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 19:35
CPC Classifications
C; C03; C03C; C03C14/00; C03C14/002; C03C17/00; C03C17/22; C03C17/23; F; F01; F01D; F01D11/00; F01D11/08; F01D11/12; F01D11/122; C03C2214/00; C03C2214/02; C03C2214/20; C03C2217/00; C03C2217/20; C03C2217/21; C03C2217/22; C03C2217/23; Y; Y02; Y02T; Y02T50/00; Y02T50/60; Y10; Y10S; Y10S277/00; Y10S277/935; Y10S277/936; Y10S277/938
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
25 words
An abradable seal comprising a high temperature stable silicon carbide fiber reinforced glass or glass-ceramic matrix base having at least one abradable ceramic layer thereon.
Claim 2
Dependent Claim
25 words
An abradable seal comprising a high temperature stable silicon carbide fiber reinforced glass or glass-ceramic matrix base having at least one abradable ceramic layer thereon.
Claim 3
Dependent Claim
38 words
The abradable seal of claim 1 wherein the abradable ceramic layer is stable at temperatures up to about 3000° F. (1648° C.) and has a coefficient of thermal expansion up to three times that of the base material.
Claim 4
Dependent Claim
24 words
The abradable seal of claim 2 wherein the abradable ceramic layer has a coefficient of thermal expansion about two times that of the substrate.
Claim 5
Dependent Claim
27 words
The abradable seal of claim 1 wherein the matrix is a glass selected from the group consisting of aluminosilicate, borosilicate, high silica content glass and mixtures thereof.
Claim 6
Dependent Claim
26 words
The abradable seal of claim 1 wherein the matrix is a glass-ceramic selected from the group consisting of lithium aluminosilicate, magnesium aluminosilicate, aluminosilicate, and mixtures thereof.
Claim 7
Dependent Claim
18 words
The abradable seal of claim 1 wherein the abradable ceramic layer comprises mullite, zirconium oxide, or mixtures thereof.
Claim 8
Dependent Claim
22 words
The abradable seal of claim 6 wherein the abradable ceramic layer comprises a plurality of discrete layers of mullite and zirconium oxide.
Claim 9
Dependent Claim
34 words
The abradable seal of claim 6 wherein the abradable ceramic layer comprises a mixture of mullite and zirconium oxide in a graded layer increasing from 100% mullite to 100% zirconium oxide or vice versa.
Claim 10
Dependent Claim
41 words
The abradable seal of claim 1 wherein the abradable layer comprises a mixture of abradable ceramic and glass-ceramic matrix material in a graded layer increasing from 100% glass-ceramic matrix next to the base to 100% abradable ceramic away from the base.
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) | 1990-11-02 | 1991-05-04 | 1991-11-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-11-02 | 1995-05-04 | 1995-11-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-11-02 | 1999-05-04 | 1999-11-03 | $7700.00 | Window Closed / Lapsed |