U.S. patent application number 14/193241 was filed with the patent office on 2015-09-03 for coated article and method for producing coating.
This patent application is currently assigned to GENERAL ELECTRIC COMPANY. The applicant listed for this patent is GENERAL ELECTRIC COMPANY. Invention is credited to Krishnamurthy ANAND, Murali Krishna KALAGA, Surinder Singh PABLA, Padmaja PARAKALA, Bala Srinivasan PARTHASARATHY.
Application Number | 20150247413 14/193241 |
Document ID | / |
Family ID | 52484405 |
Filed Date | 2015-09-03 |
United States Patent
Application |
20150247413 |
Kind Code |
A1 |
PABLA; Surinder Singh ; et
al. |
September 3, 2015 |
COATED ARTICLE AND METHOD FOR PRODUCING COATING
Abstract
A coated article and a method for producing a coating are
disclosed. Producing the coating includes providing a substrate
defining a substrate surface having a substrate erosion resistance
and applying a matrix and ceramic particles to the substrate
surface. The matrix includes an anodic material having an anodic
erosion resistance. The ceramic particles include a first ceramic
having a first ceramic erosion resistance and a second ceramic
having a second ceramic erosion resistance. The first ceramic
erosion resistance is greater than the second ceramic erosion
resistance, greater than the anodic erosion resistance, and greater
than the substrate erosion resistance. The second ceramic interacts
inchoately with the anodic material during the applying to form
modified ceramic particles and modified anodic material formations.
The modified ceramic particles are capable of forming a passive
oxide film. The coated article includes the substrate and the
coating on the substrate surface.
Inventors: |
PABLA; Surinder Singh;
(Greer, SC) ; ANAND; Krishnamurthy; (Bangalore,
IN) ; KALAGA; Murali Krishna; (Bangalore, IN)
; PARAKALA; Padmaja; (Sydney, AU) ; PARTHASARATHY;
Bala Srinivasan; (Bangalore, IN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
GENERAL ELECTRIC COMPANY |
Schenectady |
NY |
US |
|
|
Assignee: |
GENERAL ELECTRIC COMPANY
Schenectady
NY
|
Family ID: |
52484405 |
Appl. No.: |
14/193241 |
Filed: |
February 28, 2014 |
Current U.S.
Class: |
428/457 ;
427/123; 427/126.1; 427/58 |
Current CPC
Class: |
C23C 30/00 20130101;
Y10T 428/31678 20150401; C23C 4/06 20130101; F01D 5/284 20130101;
F01D 5/288 20130101; F01D 5/286 20130101 |
International
Class: |
F01D 5/28 20060101
F01D005/28; C23C 30/00 20060101 C23C030/00 |
Claims
1. A method for producing a coating, comprising: providing a
substrate defining a substrate surface having a substrate erosion
resistance; and applying a matrix and ceramic particles to the
substrate surface, wherein: the matrix includes an anodic material
having an anodic erosion resistance; and the ceramic particles
include: a first ceramic having a first ceramic erosion resistance;
and a second ceramic having a second ceramic erosion resistance,
wherein the first ceramic erosion resistance is: greater than the
second ceramic erosion resistance; greater than the anodic erosion
resistance; and greater than the substrate erosion resistance,
wherein the second ceramic interacts inchoately with the anodic
material during the applying to form modified ceramic particles and
modified anodic material formations, and wherein the modified
ceramic particles are capable of forming a passive oxide film.
2. The method of claim 1, wherein the first ceramic erosion
resistance yields erosion of the coating of less than about 76
.mu.m over about 48,000 hours of operation under rear stage gas
turbine compressor operating conditions.
3. The method of claim 1, wherein the anodic material is selected
from a group consisting of Cr.sub.70%Ni.sub.30% (wt %), a mixture
of Ni.sub.80%Al.sub.20% (wt %) and Ni.sub.95%Al.sub.5% (wt %),
cobalt and aluminum particles in a sacrificial metallic undercoat
with a ceramic overcoat, a metallurgically bonded aluminide with an
aluminum surface layer, NiCrAl and combinations thereof.
4. The method of claim 3, wherein the anodic material is
Cr.sub.70%Ni.sub.30% (wt %).
5. The method of claim 1, wherein the first ceramic is tungsten
carbide and the second ceramic is chromium carbide, chromium
nitride or a combination of chromium carbide and chromium
nitride.
6. The method of claim 5, wherein: the anodic material contains
chromium and nickel; the second ceramic interacts inchoately with
the chromium and nickel in the anodic material during the applying
to form the modified ceramic particles and the modified anodic
material formations; and the modified ceramic particles include at
least one of modified chromium carbide particles having a range of
chromium carbide stoichiometries and modified chromium nitride
particles having a range of chromium nitride stoichiometries.
7. The method of claim 5, wherein the coating contains from about
30% to about 60% by weight tungsten carbide, from about 20% to
about 50% by weight of one or both of chromium carbide and chromium
nitride, and balance essentially anodic material.
8. The method of claim 1, wherein the ceramic particles have an
average particle diameter ranging from about 0.3 .mu.m to about 5
.mu.m, and the coating has an average distance between the ceramic
particles ranging from about 0.2 .mu.m to about 2 .mu.m.
9. The method of claim 1, wherein the substrate is selected from a
group consisting of a compressor blade, a compressor vane, a
centrifugal pump impeller, and a pipeline.
10. The method of claim 1, wherein producing the coating consists
essentially of applying a single matrix of anodic material with
ceramic particles dispersed therein.
11. A coated article, comprising: a substrate defining a substrate
surface having a substrate erosion resistance; and a coating on the
substrate surface, wherein the coating includes: a matrix including
an anodic material having an anodic erosion resistance; ceramic
particles including: a first ceramic having a first ceramic erosion
resistance; and a second ceramic having a second ceramic erosion
resistance; and modified ceramic particles and modified anodic
material formations formed by an inchoate interaction between the
second ceramic and the anodic material, wherein the first ceramic
erosion resistance is: greater than the second ceramic erosion
resistance; greater than the anodic erosion resistance; and greater
than the substrate erosion resistance, and wherein the modified
ceramic particles are capable of forming a passive oxide film.
12. The coated article of claim 11, wherein the first ceramic
erosion resistance yields erosion of the coating of less than about
76 .mu.m over about 48,000 hours of operation under rear stage gas
turbine compressor operating conditions.
13. The coated article of claim 11, wherein the anodic material is
selected from a group consisting of Cr.sub.70%Ni.sub.30% (wt %), a
mixture of Ni.sub.80%Al.sub.20% (wt %) and Ni.sub.95%Al.sub.5% (wt
%), cobalt and aluminum particles in a sacrificial metallic
undercoat with a ceramic overcoat, a metallurgically bonded
aluminide with an aluminum surface layer, NiCrAl, and combinations
thereof
14. The coated article of claim 12, wherein the anodic material is
Cr.sub.70%Ni.sub.30% (wt %).
15. The coated article of claim 11, wherein the first ceramic
tungsten carbide and the second ceramic is chromium carbide,
chromium nitride or a combination of chromium carbide and chromium
nitride.
16. The coated article of claim 14, wherein: the anodic material
contains chromium and nickel; the modified ceramic particles and
the modified anodic material formations are formed by the inchoate
interaction of the second ceramic with the chromium and nickel in
the anodic material; and the modified ceramic particles include at
least one of modified chromium carbide particles having a range of
chromium carbide stoichiometries and modified chromium nitride
particles having a range of chromium nitride stoichiometries,
17. The coated article of claim 14, wherein the coating contains
from about 30% to about 60% by weight tungsten carbide, from about
20% to about 50% by weight of one or both of chromium carbide and
chromium nitride, and balance essentially anodic material.
18. The coated article of claim 11, wherein the ceramic particles
have an average particle diameter ranging from about 0.3 .mu.m to
about .mu.m, and the coating has an average distance between the
ceramic particles ranging from about 0.2 .mu.m to about 2
.mu.m.
19. The coated article of claim 11 wherein the substrate is
selected from a group consisting of a compressor blade, a
compressor vane, a centrifugal pump impeller, and a pipeline.
20. The coated article of claim 11, wherein the coating consists
essentially of a single matrix of anodic material with ceramic
particles dispersed therein.
Description
FIELD OF THE INVENTION
[0001] The present invention is directed to a coated article and a
method for producing a coating. More specifically, the present
invention is directed to a coated article and a method for
producing a coating containing an anodic material and ceramic
particles.
BACKGROUND OF THE INVENTION
[0002] Gas and steam turbine components, particularly rear stage
gas turbine compressor blades, rear stage gas turbine compressor
vanes and centrifugal pump impellers, in addition to pipelines, are
subjected to water droplet erosion, particulate deposition and
corrosion pitting induced cracking issues caused by on-line water
washing. The preceding surface degradation mechanisms may also
result in undesirable increases in surface roughness.
[0003] Changing the material of the components may improve
corrosion resistance but may not improve the roughening effect.
Developing alternate alloys may not be cost effective and
re-designing components to achieve better overall robustness may
not be feasible due to the time and cost involved as well the
design constraints imposed by the materials used and the operating
requirements.
[0004] Fouling of components may cause corrosion of the components
underneath the deposits through a crevice corrosion mechanism.
Additionally, particulates in the intake air may cause erosion
through foreign object damage to the components thereby causing
corrosion. Water wash cycles are often performed to remove the
particulates that have built up on the components. However, the
water wash cycles expose the components to increased amounts of
moisture, which may cause corrosion of the components by dissolving
and leaching corrosive agents entrapped in the surface deposits,
and accelerated corrosion to any portions of the components damaged
by foreign object damage. Furthermore, the water wash cycles may
utilize chemicals to remove complex particulate buildup. These
chemicals may increase corrosion of the components and increase
maintenance cost of the components.
[0005] Coating systems which require more than one coating layer to
address corrosion, oxidation, fouling and/or erosion are
undesirable because multiple layers may result in excessive overall
thickness of the component so coated. Additionally, multiple
coatings may increase the likelihood of undesirable alterations in
the aerodynamics or fluid dynamics of the component, or detrimental
increases in the weight of the component.
[0006] Unchecked corrosion, oxidation, fouling and/or erosion of
the exposed surfaces of the gas turbine or steam turbine
components, or of pipelines, may result in undesirable increases in
surface roughness, thereby decreasing the efficiency.
[0007] Coated components and methods for producing coated
components that do not suffer from one or more of the above
drawbacks would be desirable in the art.
BRIEF DESCRIPTION OF THE INVENTION
[0008] In one embodiment, a method for producing a coating includes
providing a substrate defining a substrate surface having a
substrate erosion resistance and applying a matrix and ceramic
particles to the substrate surface. The matrix includes an anodic
material having an anodic erosion resistance. The ceramic particles
include a first ceramic having a first ceramic erosion resistance
and a second ceramic having a second ceramic erosion resistance.
The first ceramic erosion resistance is greater than the second
ceramic erosion resistance, greater than the anodic erosion
resistance, and greater than the substrate erosion resistance. The
second ceramic interacts inchoately with the anodic material during
the applying to form modified ceramic particles and modified anodic
material formations. The modified ceramic particles are capable of
forming a passive oxide film.
[0009] In another embodiment a coated article includes a substrate
defining a substrate surface having a substrate erosion resistance
and a coating on the substrate surface. The coating includes a
matrix and ceramic particles. The matrix includes an anodic
material having an anodic erosion resistance. The ceramic particles
include a first ceramic having a first ceramic erosion resistance
and a second ceramic having a second ceramic erosion resistance.
The coating also includes modified ceramic particles and modified
anodic material formations formed by an inchoate interaction
between the second ceramic and the anodic material. The first
ceramic erosion resistance is greater than the second ceramic
erosion resistance, greater than the anodic erosion resistance, and
greater than the substrate erosion resistance. The modified ceramic
particles are capable of forming a passive oxide film.
[0010] Other features and advantages of the present invention will
be apparent from the following more detailed description, taken in
conjunction with the accompanying drawings which illustrate, by way
of example, the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a perspective view of a coated article, according
to an embodiment of the disclosure.
[0012] FIG. 2 is a sectional view along lines 2-2 of FIG. 1 of the
coated article, according to an embodiment of the disclosure.
[0013] FIG. 3 is a sectional view of a coated article including a
passive oxide film, according to an embodiment of the
disclosure.
[0014] Wherever possible, the same reference numbers will be used
throughout the drawings to represent the same parts.
DETAILED DESCRIPTION OF THE INVENTION
[0015] Provided are a coated article and a method for producing a
coating. Embodiments of the present disclosure, in comparison to
methods and articles not using one or more of the features
disclosed herein, decrease substrate corrosion, decrease substrate
oxidation, decrease substrate fouling, decrease substrate erosion,
decrease the rate at which the surface roughness of a substrate
increases, decrease maintenance costs, increase efficiency, or a
combination thereof.
[0016] Referring to FIG. 1, in one embodiment, a coated article 100
is depicted. In one embodiment, the coated article 100 is any
suitable component, for example, a compressor blade 102 (shown), a
compressor vane, a centrifugal pump impeller or a pipeline. The
term "blade" as used herein is intended to be synonymous with the
term "bucket."
[0017] Referring to FIG. 2, in one embodiment the coated article
100 includes a substrate 202 defining a substrate surface 204
having a substrate erosion resistance, and a coating 206 on the
substrate surface 204. The coating 206 includes a matrix 210
including an anodic material 212 having an anodic erosion
resistance, and ceramic particles 214. The anodic material 212 may
be anodic with respect to the substrate 202. The ceramic particles
214 include a first ceramic 216 having a first ceramic erosion
resistance and a second ceramic 218 having a second ceramic erosion
resistance. The coating 206 also includes modified ceramic
particles 220 and modified anodic material formations 222 formed
from an inchoate interaction between the second ceramic 218 and the
anodic material 212. The coating 206 defines a coating surface 224
which is exposed to the external environment. In a further
embodiment, the first ceramic erosion resistance is greater than
the second ceramic erosion resistance, greater than the anodic
erosion resistance, and greater than the substrate erosion
resistance.
[0018] In one embodiment, the anodic material 212 includes
Cr.sub.70%Ni.sub.30% (wt %), a mixture of Ni.sub.80%Al.sub.20% (wt
%) and Ni.sub.95%Al.sub.5% (wt %), cobalt and aluminum particles in
a sacrificial metallic undercoat with a ceramic overcoat, a
metallurgically bonded aluminide with an aluminum surface layer,
NiCrAl, or a combination thereof. In a further embodiment, the
anodic material 212 is operative to protect the substrate surface
204 from corrosion during downtime, which is endemic in peaking
turbine components and not uncommon even in base loaded turbine
components.
[0019] In one embodiment, the first ceramic 216 is tungsten carbide
and the second ceramic 218 is chromium carbide, chromium nitride or
a combination of chromium carbide and chromium nitride. In a
further embodiment, the anodic material 212 contains chromium and
nickel, and the second ceramic interacts inchoately with the
chromium and nickel in the anodic material 212 during the applying
to form the modified ceramic particles 220 and the modified anodic
material formations 222. The modified ceramic particles 220 include
at least one of modified chromium carbide particles having a range
of chromium carbide stoichiometries and modified chromium nitride
particles having a range of chromium nitride stoichiometries.
Without being bound by theory, it is believed that a portion of the
second ceramic dissolves during thermal spray processing, releasing
free chromium and at least one of carbon and nitrogen. The free
chromium may push the electrochemical potential of the matrix
toward being more anodic. Nitrogen when dissolved in the matrix may
improve pitting resistance of the matrix under corrosive
conditions.
[0020] In one embodiment, the coating 206 contains from about 30%
to about 60% by weight tungsten carbide, alternatively from about
30% to about 40%, alternatively from about 40% to about 50%,
alternatively from about 50% to about 60%. In an additional
embodiment, the coating 206 further contains from about 20% to
about 50% by weight of one or both of chromium carbide and chromium
nitride, alternatively from about 20% to about 30%, alternatively
from about 30% to about 40% alternatively from about 40% to about
50%. In a further embodiment, the coating 206 also contain balance
essentially anodic material 212.
[0021] Referring to FIG. 3, in one embodiment, the modified ceramic
particles 220 are capable of forming a passive oxide film 302. In a
further embodiment, the passive oxide film 302 forms under standard
rear stage turbine compressor operating conditions. Known rear
stage turbine compressor operating conditions include, for example,
elevated pressures 10-25 times atmospheric pressure, and being
subjected to adiabatic heating to 250-677.degree. C. For example,
when formed, the passive oxide film 302 defines the coating surface
224. The passive oxide film 302 resists increases in the roughness
of the coating surface 224 caused by oxidation. Without being bound
by theory, it is believed that because the passive oxide film 302
include materials which are oxides, these materials will not
undergo further oxidation.
[0022] In one embodiment, the passive oxide film 302 is uniformly,
or substantially uniformly, distributed on the matrix 210. In
another embodiment, the passive oxide film 302 has a thickness of
between about 0.1 .mu.m to about 3 .mu.m, alternatively between
about 0.1 .mu.m to about 2 =m, alternatively between about 0.1
.mu.m to about 1 .mu.m, alternatively between about 1 .mu.m to
about 2 .mu.m, alternatively between about 2 .mu.m to about 3
.mu.m, alternatively between about 0.1 .mu.m to about 1.5 .mu.m,
alternatively between about 1.5 .mu.m to about 3 .mu.m,
alternatively between about 0.1 .mu.m to about 0.5 .mu.m,
alternatively between about 0.5 .mu.m to about 1 .mu.m,
alternatively between about 1 .mu.m to about 1.5 .mu.m,
alternatively between about 1.5 .mu.m to about 2 .mu.m.
[0023] The coating 206 is produced by any suitable method. In one
embodiment, a method for applying the coating 206 includes
providing the substrate 202 defining the substrate surface 204 and
applying the matrix 210 and the ceramic particles 214 to the
substrate surface 204. Applying the matrix 210 and the ceramic
particles 214 to the substrate surface 204 may be accomplished by
any suitable coating techniques, such as, but not limited to,
thermal spray, air plasma spray (APS), high velocity oxygen fuel
(HVOF) thermal spray, high velocity air fuel spraying (HVAF),
vacuum plasma spray (VPS), electron-beam physical vapor deposition
(EBPVD), chemical vapor deposition (CVD), ion plasma deposition
(IPD), combustion spraying with powder or rod, cold spray, sol gel,
electrophoretic deposition, tape casting, polymer derived ceramic
coating, slurry coating, dip-application, vacuum-coating
application, curtain-coating application, brush-application,
roll-coat application, and agglomeration and sintering followed by
spray drying.
[0024] In one embodiment, the ceramic particles 214 have an average
particle diameter ranging from about 0.3 .mu.m to about 5 .mu.m,
alternatively from about 0.3 .mu.m to about 2.5 .mu.m,
alternatively from about 2.5 .mu.m to about 5 .mu.m, alternatively
from about 0.3 .mu.m to about 2 .mu.m, alternatively from about 2
.mu.m to about 3.5 .mu.m, alternatively from about 3.5 .mu.m to
about 5 .mu.m, alternatively from about 0.3 .mu.m to about 1 .mu.m,
alternatively from about 2 .mu.m to about 3 .mu.m, alternatively
from about 3 .mu.m to about 4 .mu.m, alternatively from about 4
.mu.m to about 5 .mu.m.
[0025] In one embodiment, the coating 206 has an average distance
between the ceramic particles 214 ranging from about 0.2 .mu.m to
about 2 .mu.m, alternatively from about 0.2 .mu.m to about 1 .mu.m,
alternatively from about 1 .mu.m to about 2 .mu.m, alternatively
from about 0.2 .mu.m to about 0.8 .mu.m, alternatively from about
0.8 .mu.m to about 1.4 .mu.m, alternatively from about 1.4 .mu.m to
about 2 .mu.m.
[0026] In one embodiment, the coating 206 has a thickness of
between about 50 .mu.m to about 250 .mu.m, alternatively between
about 50 .mu.m to about 150 .mu.m, alternatively between about 100
.mu.m to about 200 .mu.m, alternatively between about 150 .mu.m to
about 250 .mu.m, alternatively between about 50 .mu.m to about 100
.mu.m, alternatively between about 100 .mu.m to about 150 .mu.m,
alternatively between about 150 .mu.m to about 200 .mu.m,
alternatively between about 200 .mu.m to about 250 .mu.m.
[0027] In one embodiment, the coating 206 consists essentially of a
single matrix 210 of anodic material 212 with a plurality of
ceramic particles 214 dispersed therein. A single matrix 210 of
anodic material 212, as opposed to multiple layers of anodic
material 212, allows for the thickness of the coating 206 to be
minimized.
[0028] In one embodiment, the ceramic particles 214 including the
first ceramic 216 having a first ceramic erosion resistance are
capable of resisting increases in the roughness of the coating
surface 224. Without being bound by theory, it is believed that the
increased hardness of the first ceramic 216 relative to the
hardness of the second ceramic 218 and the anodic material 212
confers resistance to deposition of particles and subsequent
corrosion of the coating surface 224.
[0029] In one embodiment, wherein the coating 206 has a thickness
less than about 250 .mu.m, alternatively less than about 150 .mu.m,
the property corresponding to erosion resistance includes erosion
of the coating 206 of less than about 76 .mu.m over about 48,000
hours of operation under standard rear stage turbine compressor
operating conditions.
[0030] In one embodiment, the anodic material 212 in the matrix 210
is capable of resisting increases in the roughness of the coating
surface 224. Without being bound by theory, it is believed that the
anodic material 212 protects the substrate 202 from corrosion by
undergoing anodic dissolution preferentially as the substrate 202
is placed at a nobler cathodic potential compared to the matrix
210. The anodic material 212 is metallic in nature and possesses
necessary toughness and ductility. However to resist deposition,
particulate and water droplet erosion the matrix 210 is
strengthened by ceramic particles 214. The first ceramic 216 in the
ceramic particles 214 address erosion resistance. The second
ceramic 218 in the ceramic particles 214, such as chromium carbide
and chromium nitride dissolves during application, such as by
thermal spray, to release free chromium, which further augments the
anodic nature of the matrix 210.
[0031] While the invention has been described with reference to one
or more embodiments, it will be understood by those skilled in the
art that various changes may be made and equivalents may be
substituted for elements thereof without departing from the scope
of the invention. In addition, many modifications may be made to
adapt a particular situation or material to the teachings of the
invention without departing from the essential scope thereof.
Therefore, it is intended that the invention not be limited to the
particular embodiment disclosed as the best mode contemplated for
carrying out this invention, but that the invention will include
all embodiments falling within the scope of the appended
claims.
* * * * *