U.S. patent application number 17/840983 was filed with the patent office on 2022-09-29 for airfoil conformable membrane erosion coating.
This patent application is currently assigned to Raytheon Technologies Corporation. The applicant listed for this patent is Raytheon Technologies Corporation. Invention is credited to Nicholas D. Stilin.
Application Number | 20220307379 17/840983 |
Document ID | / |
Family ID | 1000006394792 |
Filed Date | 2022-09-29 |
United States Patent
Application |
20220307379 |
Kind Code |
A1 |
Stilin; Nicholas D. |
September 29, 2022 |
Airfoil Conformable Membrane Erosion Coating
Abstract
A coating membrane for a component of a gas-turbine engine
includes a solid membrane having a metallic foil or a polymeric
film, and having a thickness and at least one kerf extending
through the thickness to define a kerf pattern such that the solid
membrane can be applied to a compound-curved surface. Also
disclosed are a coated component coated with the membrane, and a
method for producing a coated component with the membrane.
Inventors: |
Stilin; Nicholas D.;
(Higganum, CT) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Raytheon Technologies Corporation |
Farmington |
CT |
US |
|
|
Assignee: |
Raytheon Technologies
Corporation
Farmington
CT
|
Family ID: |
1000006394792 |
Appl. No.: |
17/840983 |
Filed: |
June 15, 2022 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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16047319 |
Jul 27, 2018 |
11408291 |
|
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17840983 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
Y10T 428/12361 20150115;
F01D 5/288 20130101; F05D 2220/32 20130101; F05D 2300/43 20130101;
F05D 2300/171 20130101; F05D 2300/611 20130101; B32B 2250/02
20130101; B32B 2603/00 20130101; B32B 7/12 20130101; F05D 2240/30
20130101; B32B 15/08 20130101; F05D 2300/44 20130101; F05D 2300/603
20130101; B32B 15/01 20130101; F05D 2300/174 20130101; B32B
2307/554 20130101; F05D 2240/12 20130101 |
International
Class: |
F01D 5/28 20060101
F01D005/28; B32B 15/08 20060101 B32B015/08; B32B 7/12 20060101
B32B007/12; B32B 15/01 20060101 B32B015/01 |
Claims
1. A coating membrane for a component of a gas-turbine engine,
comprising: a solid membrane comprising a polymeric film having a
thickness and at least one kerf extending through the thickness to
define a kerf pattern such that the solid membrane can be applied
to a compound-curved surface.
2-4. (canceled)
5. The coating membrane of claim 1, wherein the polymeric film is
selected from the group consisting of films of epoxy resin,
polyphenylene ether, polyurethane and combinations thereof.
6. The coating membrane of claim 1, wherein the polymeric film is
an elastomeric film.
7. The coating membrane of claim 1, wherein the polymeric film is
fiber reinforced.
8. The coating membrane of claim 1, wherein the solid membrane has
a thickness of between about 0.003 and about 0.030 inches.
9. The coating membrane of claim 1, wherein the at least one kerf
has a kerf width of between 0.002 and 0.006 inches.
10. The coating membrane of claim 1, wherein the kerf pattern
defines a reticulated kerf pattern in a monolithic membrane
structure.
11. The coating membrane of claim 1, wherein the kerf pattern is a
recurring pattern of intersecting kerfs.
12. The coating membrane of claim 1, wherein the kerf pattern is
defined by the at least one kerf in a spiral pattern.
13. A coated gas-turbine engine component, comprising: a surface of
a gas-turbine engine component; a solid membrane comprising a
polymeric film having a thickness and at least one kerf extending
through the thickness to define a kerf pattern, wherein the solid
membrane is bonded to the surface.
14. The coated gas-turbine engine component of claim 13, wherein
the surface is a compound-curved surface, and wherein the solid
membrane conforms to the compound-curved surface.
15. The coated gas-turbine engine component of claim 13, wherein
the surface comprises a polymer matrix composite material.
16. A method for applying an erosion resistant coating to a
component of a gas-turbine engine, comprising: applying a solid
membrane to a surface of a component of a gas-turbine engine, the
solid membrane comprising a polymeric film having a thickness and
at least one kerf extending through the thickness to define a kerf
pattern; and bonding the solid membrane to the surface.
17. The method of claim 16, wherein the surface is a
compound-curved surface, and wherein the applying step conforms the
solid membrane to the compound-curved surface.
18. The method of claim 16, wherein the bonding step comprises
co-curing the solid membrane with the component.
19. The method of claim 16, wherein the bonding step comprises
adhesively bonding the solid membrane to the component.
20. The method of claim 16, wherein the surface comprises a polymer
matrix composite material.
21. The coating membrane of claim 1, wherein the kerf pattern is
defined by at least one elongated slit passing through the solid
membrane.
Description
BACKGROUND OF THE DISCLOSURE
[0001] The disclosure relates to protection of components in
gas-turbine engines and the like from erosion and to provide impact
resistance. More particularly, the disclosure relates to a
conformable membrane coating.
[0002] Laminate polymer matrix composites (PMCs) are used to form
both rotating (blades) and stationary (vanes) airfoils for use in
airborne propulsion gas-turbines. PMCs are utilized for various
reasons, particularly to save weight. Unfortunately, these
materials do not possess erosion resistance comparable to metallic
materials and often require erosion resistant coatings to meet
required life expectancy.
[0003] Many erosion resistant coatings are elastomers that have
maximum usage temperatures that limit their use. An erosion coating
that could endure high temperature environments would be
beneficial. In addition, an erosion coating that could be applied
where traditional spraying (line of sight) or tank dipping is not
feasible would also be beneficial.
[0004] The present disclosure addresses these issues.
SUMMARY OF THE INVENTION
[0005] The present disclosure relates to a solid membrane for
providing erosion resistance to airfoils and other like components,
particularly to those which are made from polymer matrix
composites. The membrane is comprised of a metallic foil or
polymeric film which is flexible and which has a kerf pattern
defined thereon to enhance flexibility of the solid membrane.
[0006] In one configuration, a coating membrane for a component of
a gas-turbine engine comprises a solid membrane comprising a
metallic foil or a polymeric film, and having a thickness and at
least one kerf extending through the thickness to define a kerf
pattern such that the solid membrane can be applied to a
compound-curved surface.
[0007] In another non-limiting configuration, the solid membrane
comprises a metallic foil.
[0008] In a further non-limiting configuration, the metallic foil
is selected from the group consisting of foils of titanium alloy,
nickel alloy, stainless ferrous alloy and combinations thereof.
[0009] In a further non-limiting configuration, the solid membrane
comprises a polymeric film.
[0010] In a still further non-limiting configuration, the polymeric
film is selected from the group consisting of films of epoxy resin,
polyphenylene ether, polyurethane and combinations thereof.
[0011] In still another non-limiting configuration, the polymeric
film is an elastomeric film.
[0012] In a further non-limiting configuration, the polymeric film
is fiber reinforced.
[0013] In a still further non-limiting configuration, the solid
membrane has a thickness of between about 0.003 and about 0.030
inches.
[0014] In a further non-limiting configuration, the at least one
kerf has a kerf width of between 0.002 and 0.006 inches.
[0015] In another non-limiting configuration, the kerf pattern
defines a reticulated kerf pattern in a monolithic membrane
structure.
[0016] In still another non-limiting configuration, the kerf
pattern is a recurring pattern of intersecting kerfs.
[0017] In a further non-limiting configuration, the kerf pattern is
defined by the at least one kerf in a spiral pattern.
[0018] In another non-limiting configuration, a coated gas-turbine
engine component comprises a surface of a gas-turbine engine
component; a solid membrane comprising a metallic foil or a
polymeric film, the membrane having a thickness and at least one
kerf extending through the thickness to define a kerf pattern,
wherein the solid membrane is bonded to the surface.
[0019] In still another non-limiting configuration, the surface is
a compound-curved surface, and the solid membrane conforms to the
compound-curved surface.
[0020] In a further non-limiting configuration, the surface
comprises a polymer matrix composite material.
[0021] In a further non-limiting configuration, a method for
applying an erosion resistant coating to a component of a
gas-turbine engine comprises applying a solid membrane to a surface
of a component of a gas-turbine engine, the solid membrane
comprising a metallic foil or a polymeric film, the membrane having
a thickness and at least one kerf extending through the thickness
to define a kerf pattern; and bonding the solid membrane to the
surface.
[0022] In a still further non-limiting configuration, the surface
is a compound-curved surface, and the applying step conforms the
solid membrane to the compound-curved surface.
[0023] In another non-limiting configuration, the bonding step
comprises co-curing the solid membrane with the component.
[0024] In still another non-limiting configuration, the bonding
step comprises adhesively bonding the solid membrane to the
component.
[0025] In a further non-limiting configuration, the surface
comprises a polymer matrix composite material.
[0026] The details of one or more embodiments of the disclosure are
set forth in the accompanying drawings and the description below.
Other features, objects, and advantages will be apparent from the
description and drawings, and from the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] FIG. 1 illustrates a polymer matrix composite component of a
gas-turbine engine with a conformable erosion resistant coating
according to one non-limiting embodiment of the disclosure;
[0028] FIG. 2 shows a non-limiting embodiment of a kerf pattern on
a conformable erosion resistant coating;
[0029] FIG. 3 shows another non-limiting embodiment of a kerf
pattern on a conformable erosion resistant coating; and
[0030] FIG. 4 shows another non-limiting embodiment of a kerf
pattern on a conformable erosion resistant coating.
[0031] Like reference numbers and designations in the various
drawings indicate like elements.
DETAILED DESCRIPTION
[0032] The invention relates to a conformable membrane coating for
providing erosion and/or impact resistance to components of a
gas-turbine engine. The coating is particularly suitable for
components having curved or compound-curved surfaces such as
airfoils or the like.
[0033] FIG. 1 shows an airfoil component 10, with two vanes 12
illustrated. Vanes 12 have a root or base structure 14 at one end
and outer structure 16 at the other end for mounting to other
components of the gas-turbine engine (not shown). Between
structures 14, 16, vanes 12 have a compound-curved surface 18 which
is curved and contoured to produce desired fluid flow. In the
course of operation of the gas-turbine engine, components such as
vanes 12 are impacted by high-velocity particulate matter and
possible other solid materials which can cause issues of erosion as
well as damage. Thus, vanes 12 need erosion and impact
resistance.
[0034] In a gas-turbine engine setting, weight is always a concern,
and components such as vanes 12 and the like are frequently
manufactured from light materials such as polymer matrix composites
(PMCs). PMCs have good properties from a weight and performance
standpoint, but are particularly susceptible to erosion and impact
damage. Thus, for PMCs, providing erosion and impact resistance is
of particular importance.
[0035] FIG. 1 shows vanes 12 having a coating in the form of a
membrane 20. In this illustration, vanes 12 are part of a stator,
with membrane 20 applied to the airfoil pressure surface of the
stator. Of course, membrane 20 could be applied in numerous other
locations throughout the gas-turbine engine.
[0036] Membrane 20 is provided from a metallic foil or polymeric
film such that the material has some flexibility itself. In
addition, membrane 20 is provided with one or more kerfs 22, or
very narrow slits, which define a kerf pattern that provides even
further flexibility and conformability to membrane 20. Kerfs 22
allow membrane 20 to closely conform to the particular contours of
the component or component surface to be coated. Thus, membrane 20
as disclosed herein is well suited for use on curved surfaces such
as airfoils, or blade leading or trailing edges or the like.
[0037] Membrane 20 can in one non-limiting embodiment be provided
from metallic foil such as, for example titanium alloy foil, nickel
alloy foil, stainless ferrous foil, aluminum foil and the like.
These materials are well-suited to providing a membrane with
excellent erosion resistance and impact resistance, while also
being able to tolerate the high temperatures to which they will be
exposed without losing their erosion and impact resistant
properties.
[0038] In another non-limiting embodiment, membrane 20 can be
provided from polymeric film such as, for example, epoxy resin
film, polyphenylene ether (PPE) film, polyurethane film,
elastomeric films or the like. Such films can be fiber reinforced
if desirable. Again, polymeric films as disclosed herein can
provide excellent erosion and impact resistance while also being
able to tolerate high temperature operating conditions without
losing erosion and impact resistant properties.
[0039] Membrane 20 can have a thickness of between about 0.003 and
0.030 inches (3-30 thousandths), depending primarily upon the
application and how much erosion or impact resistance is desired.
Membrane 20 has kerfs 22 passing through the thickness of membrane
20 and defining a kerf pattern which provides additional
flexibility to membrane 20. In FIG. 1, the kerf pattern depicted is
a spiral kerf pattern wherein the entire pattern is defined by a
single spiraling kerf. Such a kerf pattern, as well as others to be
disclosed below, provide good flexibility to membrane 20, for
example by allowing in-plane shear along the kerfs which helps
membrane 20 drape or conform to compound-curved surfaces without
wrinkling or other problems, while maintaining membrane 20 as a
single monolithic component. It should be appreciated that a thin
foil should be sufficient for erosion protection, but thicker foils
could be considered for impact protection. Foils with non-constant
thickness could also be applied, such as a thicker membrane in
areas where impact resistance is desirable.
[0040] Kerfs can have a width which is sufficiently narrow that
particle impacts are not likely to damage the membrane. For
example, in one non-limiting embodiment, kerfs can have a width of
between about 0.002 and 0.006 inches (2 and 6 thousandths). Some
flexibility is provided by kerfs in the form of notches in the
surface of the membrane, but the best flexibility is found when
kerfs pass through the entire thickness of the membrane. As set
forth above, this allows for shearing in-plane along the kerf to
make portions of the membrane highly mobile relative to the rest of
the membrane. Kerf width should be sufficiently small that
breeching by erosive particles does not occur. In some instances,
it may be desirable to enhance surface continuity with infiltration
of adhesive or matrix resin. In all cases, the reticulated pattern
provides drapability to the membrane but is constructed such that
the resulting membrane remains monolithic. No kerf subdivides the
membrane into multiple pieces.
[0041] FIG. 2 illustrates an alternative and non-limiting
embodiment of a different kerf pattern which is formed by two
interspersed repeating patterns, one in the form of a small cross
24 and the other in the form of a Z (illustrated at 26). The Z
patterns are rotated to different orientations through the kerf
pattern.
[0042] FIG. 3 illustrates another alternative and non-limiting
embodiment with still a different kerf pattern which is formed by
mirror image interspersed kerfs, in this case in the form of a
cross 27 with one flag (illustrated at 28).
[0043] FIG. 4 depicts another embodiment with a repeating,
interlocking kerf pattern. This pattern is formed by interlocking
oppositely wound spiral kerfs 30, 32 which can be at least
partially connected at junctions 34.
[0044] As should be apparent from a consideration of FIGS. 2-4,
kerfs 22 can be produced in membrane 20 in a number of different
patterns. The primary concerns in these patterns is to produce a
membrane which is suitably flexible or drapable so that membrane 20
can be positioned in close conformity to a complex-curved surface
such as that of an airfoil or leading or trailing edge of a blade.
All these patterns produce excellent flexibility and also maintain
membrane 20 as a monolithic structure, albeit one which is
frangible as is desirable and further discussed below.
[0045] Kerfs 22 can be formed into membrane 20 in a number of
different ways, but one particularly suitable manner is with a
laser, which is well-suited to producing uniform slots of repeating
patterns and with very narrow width of the slot. Of course, the
kerfs can be produced in other manners as well, and although laser
kerfs are particularly well-suited to the present disclosure, other
methods are possible.
[0046] The kerf pattern to be utilized can be further directed by
the specific component to be coated and protected. In any event,
however, kerfs also serve to discretize membrane 20 so that
membrane 20 is frangible. In the event a portion of membrane 20
breaks away from the component, kerfs provide breaking points so
that only a small portion breaks away. This makes the coating
useful in gas-turbine engines not only in bypass flow locations,
but also in engine core flow locations.
[0047] It is also particularly suitable for the kerf pattern to be
sufficiently applied to the membrane such that drapability and
frangibility is maintained. This produces a desirable flexibility
for use in conforming to a desired compound-curved surface, and
also to sharply bending surfaces such as blade leading or trailing
edges.
[0048] Coating using a solid membrane according to this disclosure
can provide for coating components that cannot be properly coated
with other techniques such as dipping or spraying, and also
produces an erosion and impact resistance coating which is not
limited in temperatures to which it can be exposed.
[0049] The resulting coated component can be any suitable component
of a gas-turbine engine such as, but not limited to, an airfoil of
a blade or vane, and particularly at surfaces which are subject to
impact or erosion and have compound or complex curved surfaces, or
sharp curved surfaces, or both.
[0050] The coating can be applied by draping the membrane over the
surface to be protected, such that the flexibility provided by the
material and the kerf pattern allows the membrane to closely follow
contours of the surface. The membrane can be bonded to the surface
through any method known to a person of ordinary skill in the art,
but particularly suitable methods include co-cured during
lamination, for example with a PMC component, or can be or
adhesively bonded, which can be done after curing.
[0051] It should be appreciated that the thin metallic foil
provides erosion and impact damage resistance to substrates
requiring enhanced erosion or impact damage tolerance. The metallic
coating may be used where other coatings and coating techniques
cannot be used due to use temperature limitations. The kerf pattern
promotes frangibility of the membrane should it liberate wholly or
in part during engine operation, minimizing or eliminating damage
to downstream hardware.
[0052] One or more embodiments of the present invention have been
described. Nevertheless, it will be understood that various
modifications may be made without departing from the spirit and
scope of the invention. For example, different sources of images
and/or types of images can be utilized. Accordingly, other
embodiments are within the scope of the following claims.
* * * * *