CN111088507B

CN111088507B - Method of forming high temperature electroformed component and related components

Info

Publication number: CN111088507B
Application number: CN201911017043.XA
Authority: CN
Inventors: A.J.德托尔
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 2018-10-24
Filing date: 2019-10-24
Publication date: 2023-02-21
Anticipated expiration: 2039-10-24
Also published as: CN111088507A

Abstract

An electroformed composite component includes reinforcing particles in a metal matrix. The composite member is formed by a method that includes passing an electric current between an anode and a cathode in the presence of an electrolyte. The electrolyte includes a metal salt and a plurality of reinforcing particle precursors. The method also includes depositing a composite layer on the cathode, wherein the composite layer includes a metal matrix and a plurality of reinforcement particle precursors dispersed in the metal matrix. An optional heat treatment may then be performed to convert the precursor particles to a more stable form while improving the properties of the composite.

Description

Method of forming high temperature electroformed component and related component

Cross Reference to Related Applications

This application claims priority to U.S. provisional application Serial No. 62/749,728 entitled "Methods of Forming High-Temperature electrically Components and Related Components" filed 24/10 in 2018, the entire contents of which are incorporated herein by reference.

Technical Field

The present disclosure relates to methods of forming high temperature electroformed components. More particularly, embodiments of the present disclosure relate to methods of forming composite electroformed components and related components.

Background

Electroforming is an additive manufacturing process in which metal parts are formed by electrolytically reducing metal ions (atom by atom) on the surface of a mandrel (cathode). Electroforming is used to manufacture products across an industrial range, including healthcare, electronics, and aerospace. The electroforming process provides several advantages. For example, the electroforming process is efficient, accurate, scalable, and low cost, requiring only a modest investment in both the factory and the equipment. However, challenges due to limited material selection may limit the wider application of this technology to advanced structural components. Accordingly, there remains a need for improved methods of making electroformed components, particularly high performance structural components.

Drawings

These and other features, aspects, and advantages of the present disclosure will become better understood when the following detailed description is read with reference to the accompanying drawings, wherein:

fig. 1 is a schematic illustration of an electroforming process, according to some embodiments of the present disclosure;

FIG. 2 shows the ultimate tensile strength as a function of temperature for electroformed and conventional cast and wrought materials;

FIG. 3 shows the yield strength increase versus particle size (r) and volume fraction (f);

fig. 4 illustrates boehmite (AlO (OH)) particles with a diameter of about 50 nm in a polycrystalline nickel matrix produced by a composite electroforming pathway, according to some embodiments of the disclosure;

FIG. 5 shows the structure of FIG. 4 after heat treatment; and

fig. 6 shows thermal hardness test results for a composite electroformed component, according to some embodiments of the present disclosure.

Detailed Description

In the following specification and the claims which follow, reference will be made to a number of terms which shall be defined to have the following meanings. The singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise. As used herein, the term "or" is not meant to be exclusive and means that at least one of the referenced components is present, and includes instances where a combination of the referenced components may be present, unless the context clearly dictates otherwise.

Approximating language, as used herein throughout the specification and claims, may be applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term or terms, such as "about" and "approximately," is not to be limited to the precise value specified. In some cases, the approximating language may correspond to the precision of an instrument for measuring the value. Similarly, "free" may be used in combination with a term, and may include a non-significant amount or trace amounts, while still being considered an unmodified term. Here and throughout the specification and claims, range limitations may be combined and/or interchanged, such ranges are identified and include all the sub-ranges contained therein unless context or language indicates otherwise. The terms "disposed within" or "disposed within" refer to a configuration in which at least a portion of a component is disposed within an interior or portion of another component, and do not necessarily denote that the entirety of the component needs to be disposed within another component.

As previously mentioned, electroforming is an additive manufacturing process in which metal parts are grown on a suitably shaped mandrel by electrochemical reduction of metal ions in a liquid solution. Fig. 1 is a schematic diagram of an electroforming process. As shown in fig. 1, in the electroforming process, a mandrel (cathode) and an anode are immersed in an electrolyte solution, and as a current flows between the electrodes, a part of the thickness accumulates on the surface of the mandrel as time passes. Once the desired part thickness is achieved, the mandrel may be removed by mechanical, chemical or thermal treatment to produce a free-standing metal part. In one example, the mandrel may be a low melting point material (i.e., a "fusible alloy") that can be cast into a mandrel shape and then melted for reuse after electroforming. Other mandrel options include conductive waxes and metalized plastics that can be formed by injection molding, 3D printing, and the like. In some cases, where part geometry permits, then a reusable mandrel may also be possible.

Furthermore, as previously mentioned, challenges due to limited material selection have limited the wider application of electroforming technology to advanced structural components. For example, prior art electroforming material selection for structural applications is limited to a maximum use temperature of about 500F (260 ℃). The limited temperature capability of electroformed parts depends at least in part on the limited set of material choices available today for electroforming. Most commercial electroforming operations focus on pure nickel or copper, and the only alloy that is commonly available is nickel-cobalt (sometimes with a small phosphorus addition).

This limited set of materials is due to fundamental limitations in the electrolytic process. Ideally, the electroforming system should exhibit the following characteristics: high deposition rate (> 0.001 in/hr,0.025 mm/hr), low residual stress (so that there are no cracks or deformations in the part), and high current efficiency (i.e., most of the current flowing is used to convert metal ions to solid metal, not other side reactions). Conversion to electrochemical requirements means that any metal salt used in the process should ideally have high solubility in water (for conventional processes) and high standard reduction potential (minimum energy required to reduce the metal cation). Of course, the properties of the pure metal (or alloy) should also be sufficient for the application. In view of the above, these requirements have led to a limitation in the set of nickel, copper and nickel-cobalt materials that can be used today for electroforming. Since these materials are single phase, the strength and temperature capabilities are limited to about 100 ksi (690 MPa) Ultimate Tensile Strength (UTS) at 500 ℃. (260 ℃).

As noted above, the set of materials that can be used for structural electroforming is currently limited to nickel and nickel-cobalt alloys. Although these metals have reasonable strength at low temperatures, both are limited to about 500 ° F (260 ℃) during operation. Fig. 2 shows the rapid drop in UTS for electroformed nickel and nickel-cobalt materials. In contrast, conventional cast and wrought alloys 625 and 718 exhibited relatively flat UTS responses up to 1200 ℃ F. (650 ℃). Thus, new developments in electroforming can make the alloy approach the strength and temperature stability of conventionally processed alloys 625 and 718.

Embodiments of the present disclosure address shortcomings indicated in the art. According to some embodiments of the present disclosure, electroforming may be used for additive manufacturing parts that can operate at higher temperatures greater than 500 ° F. In some embodiments of the present disclosure, electroforming may be used for additive manufactured parts that can operate at higher temperatures up to or even greater than 1200 ° F.

Embodiments of the present disclosure address issues related to strength and high temperature capability of electroformed components by employing composite materials that include a reinforcing phase. In this approach, the auxiliary reinforcing phase is suspended in the electrolyte and incorporated into the growing metal matrix during electroforming. While composite plating approaches for electroplated coatings have been explored to enhance properties such as wear resistance and lubricity, no attempt has been made to enhance structural electroforming.

By incorporating particles (e.g., nanoscale particles) into a metal matrix (e.g., nickel-based matrix), material properties can be improved through a mechanism known as dispersion strengthening. For effective reinforcement in structural applications, it may be desirable for the particles to be stable at the highest expected service operating temperatures. Further, desirably, the additional particles and the one or more phases are compatible with the matrix material (e.g., nickel-based matrix) up to the highest expected service operating temperature.

In some embodiments, the matrix comprises nickel, copper, cobalt, or a combination thereof. In certain embodiments, the matrix comprises nickel, a nickel alloy (such as a nickel tungsten or nickel molybdenum alloy), or a combination thereof. Such a substrate may be referred to hereinafter as a nickel-based substrate. Further, the plurality of particles may include particles in the form of spherical particles, fibers, tubes, flakes, or a combination thereof. In some embodiments, the plurality of reinforcing particles comprises yttria particles, alumina fibers, ceria particles, silica particles, silicon carbide particles, titanium oxide particles, titanium carbide particles, titanium nitride particles, zirconium carbide particles, carbon nanotubes, graphene, or combinations thereof, and precursors thereof.

For effective reinforcement in structural applications, it may also be desirable for one or more additional phases to have appropriate size, volume fraction, and spacing. For example, it may be desirable to enhance the dispersion of particles in the matrix sufficiently that the mean free path between particles closely conforms to a perfectly uniformly distributed free path without agglomeration.

The desired particle size and particle volume fraction in the composite can be calculated using the Orowan-Ashby equation (equation I) which predicts reinforcement due to incoherent particles in a ductile matrix

Equation I

。

Δ σ = yield strength increase, G = shear modulus, B = burgers vector, R = particle size, and f = volume fraction of particles. This version of the Orowan-Ashby equation assumes that the particles are uniformly dispersed in the matrix without agglomeration. The relationship between yield strength increase and particle size (r) and volume fraction (f) is further illustrated in fig. 3. As shown in fig. 3, reduced particle size (r) and increased fraction (f) result in higher strength. Thus, according to some embodiments of the present disclosure, smaller particles on the nanometer scale (less than about 100 nm) may be desirable. Furthermore, without being bound by any theory, it is believed that well-dispersed particles may also extend Hall-Petch (Hall-Petch) reinforcement by stabilizing grain size at higher temperatures.

Further, for uniformly dispersed particles (i.e., substantially no agglomeration), equation 2 may be used to calculate the mean free path, λ, between particles, according to some embodiments of the present disclosure.

Equation 2

。

r = particle size, and f = volume fraction of particles.

Thus, by employing the correct material microstructure and processing parameters, complex parts having wall thicknesses of 0.5 mm or greater can be fabricated by electroforming as required by the application, with acceptable strength at high temperatures beyond the capabilities of existing materials available today, according to embodiments of the present disclosure.

For example, as previously noted, currently, electroforming components are limited to low or medium temperature applications below about 500 ° F (260 ℃). By employing embodiments of the present disclosure, electroforming can be used for additive manufacturing parts that can operate at higher temperatures up to greater than 500 ° F and even up to and beyond 1200 ° F (650 ℃). Electroformed components with such temperature capability levels would enable new and important applications throughout the market. The inherent advantages of electroforming processes, including low cost and the ability to produce complex geometries, combined with high temperature performance, will open new applications in aerospace, power generation and other fields.

In some embodiments, a method of forming an electroformed composite member is presented. The method includes passing an electric current between an anode and a cathode in the presence of an electrolyte, wherein the electrolyte includes a metal salt and a plurality of precursors of reinforcing particles. In some other embodiments, the electrolyte includes a metal salt and a precursor of the reinforcing particle precursor, such as a hydroxide precursor. The hydroxide precursor can be an aluminum hydroxide material, a yttrium hydroxide material, a cerium hydroxide material, a silicon hydroxide material, a titanium hydroxide material, or a combination thereof. The method also includes depositing a composite layer on the cathode, wherein the composite layer includes a metal matrix from the metal salt and a plurality of reinforcing particle precursors dispersed in the matrix. In some embodiments, the current is Direct Current (DC). In some other embodiments, the current is pulsed according to a prescribed waveform.

Non-limiting examples of suitable metal salts include salts of nickel, copper, cobalt, or combinations thereof. In certain embodiments, the metal salt comprises a nickel salt. Non-limiting examples of suitable metal salts include chlorides, sulfates, and/or sulfamates of the metal. Further, the plurality of particles may include particles in the form of spherical particles, fibers, tubes, flakes, or a combination thereof. In some embodiments, the plurality of reinforcing particles comprises yttria particles, alumina fibers, ceria particles, silica particles, silicon carbide particles, titanium oxide particles, titanium carbide particles, titanium nitride particles, zirconium carbide particles, carbon nanotubes, graphene, or combinations thereof, and precursors thereof.

In some embodiments, the composite layer includes a nickel-based matrix and one or more of yttria particles, alumina fibers, carbon nanotubes, or graphene dispersed in the nickel-based matrix. In certain embodiments, the composite layer includes a nickel-based matrix and a plurality of boehmite or alumina particles dispersed in the nickel-based matrix.

As previously mentioned, it may also be desirable for one or more additional phases (e.g., reinforcing phases) to have appropriate size, volume fraction, and spacing for effective reinforcement in structural applications. In some embodiments, the plurality of reinforcing particles have an average particle size in a range up to about 100 nm. In some embodiments, the plurality of reinforcing particles has an average particle size in a range from about 2 nm to about 90 nm, from about 5 nm to about 80 nm, from about 10 nm to about 70 nm, from about 15 nm to about 60 nm, from about 20 nm to about 50 nm, and any intermediate range therein. In certain embodiments, the plurality of reinforcing particles have an average particle size in a range from about 5 nanometers (nm) to about 20 nm. In some embodiments, the volume fraction of the plurality of reinforcing particles in the composite layer ranges from about 1 vol% to about 20 vol%. In some embodiments, the volume fraction of the plurality of reinforcing particles in the composite layer is in a range from about 1 vol% to about 15 vol%, from about 1.5 vol% to about 12.5 vol%, from about 2 vol% to about 10 vol%, from about 2.5 vol% to about 7.5 vol%, and any intermediate ranges therein. In certain embodiments, the volume fraction of the plurality of reinforcing particles in the composite layer ranges from about 2 vol% to about 10 vol%. In some embodiments, the mean free path between the plurality of particles is in a range from about 5 nm to about 1000 nm. In some embodiments, the mean free path between the plurality of particles is in a range from about 5 nm to about 750 nm, from about 5 nm to about 500 nm, from about 10 nm to about 250 nm, from about 10 nm to about 100 nm, from about 10 nm to about 50 nm, and any intermediate ranges therein. In certain embodiments, the mean free path between the plurality of particles is in a range from about 10 nm to about 100 nm.

The method also includes depositing a composite layer on the cathode to form an electroformed component having a desired average thickness. In some embodiments, the desired average thickness is greater than 0.5 millimeters. In certain embodiments, the desired average thickness is in a range from about 0.5 millimeters to about 5 millimeters.

As previously described, methods according to embodiments of the present disclosure may advantageously allow for the fabrication of electroformed components having complex geometries with substantially uniform thicknesses. In some embodiments, the electroformed component is a component of an aircraft engine, a gas turbine, or a marine engine. In certain embodiments, the electroformed components include aircraft engine transport components, pipes, conduits, seals, vanes, airfoils, struts, liners, shells, flow path structures, leading edges, brackets, flanges, casings.

The electroformed component may have a temperature capability greater than 500 ° F. In certain embodiments, the electroformed member has a temperature capability equal to or greater than 1200 ° F. Electroformed components formed using the methods described herein are also included within the scope of the present disclosure.

As previously described, composite plating (also referred to as embedded plating) approaches have been developed for electroplating composite coatings to enhance properties such as wear resistance and lubricity. However, these approaches for composite plating have focused on relatively thin coatings, e.g., up to 100 μm thick. The coating is applied to a substrate to improve wear resistance, corrosion resistance, lubricity, oxidation resistance, and the like. Formulations used in coating applications typically contain a dispersant to keep the particles suspended in the plating bath and to prevent agglomeration of the particles. The dispersant helps to disperse the particles evenly and well in the electrodeposit rather than agglomerating or clumping together. Common dispersants include Polyethyleneimine (PEI) and Cetrimide (CTAB). While these approaches using dispersants may provide high quality coatings, they tend to increase residual stress in the deposit (by interfering with the reduction of metal in the metal salt), thus preventing the thicker deposit, e.g., greater than 100 μm, required to electroform individual structural parts that may require a thickness, e.g., greater than 0.5 mm, e.g., 1.0 mm or thicker. The dispersant also inevitably becomes entrapped in the deposit, which can have a negative effect on the properties of the deposit. For high temperature individual structural members, retention of dispersant may limit the maximum use temperature and other mechanical properties, such as UTS.

The inventors have realized that it is advantageous not to include a dispersant or surfactant in the electrochemical solution in order to form individual structural members having a thickness of, for example, 0.5 mm to 1.0 mm or more. However, there is still a need to achieve good particle dispersion in the electroforming bath. To form a free-standing structural member with the highest use temperatures required, UTS and other mechanical properties, the inventors found that one way to achieve good particle dispersion was to use precursors of the target particles desired in the final structural electroforming. The precursor should be inherently stable and well dispersed in the suspension.

As previously described, the reinforcing particles in the metal matrix of the electroformed composite member may comprise yttria particles, alumina fibers, ceria particles, silica particles, silicon carbide particles, titanium oxide particles, titanium carbide particles, titanium nitride particles, zirconium carbide particles, carbon nanotubes, graphene, or combinations thereof. The inventors have found that the use of precursor particles for the reinforcing particles results in an inherently stable and well-dispersed suspension which provides good dispersion of the reinforcing particles in the electroformed composite member.

As an example, alO has the formulaBoehmite of (OH), also called amorphous alumina or hydrous alumina or aluminum hydroxide, is used as a precursor of the alumina particles. Boehmite is highly self-dispersible in aqueous (water-based) solutions due to the presence of OH groups. The inventors have found that boehmite is also highly self-dispersed in electrolytes suitable for electroforming, including chloride, sulfate and/or sulfamate based baths of nickel, copper and nickel-cobalt. With alumina (Al) containing pure gamma (gamma) phase or alpha (alpha) phase ₂ O ₃ ) Compared to the suspension comprising boehmite, which is a prerequisite for production, is infinitely stable. The stability of the boehmite-containing suspension was tested by keeping the suspension stirred for several weeks. It was found that suspensions comprising boehmite did not tend to agglomerate, whereas suspensions comprising pure gamma (gamma) phase or alpha (alpha) phase alumina tended to show signs of agglomeration. Boehmite particles are also readily incorporated into the metal matrix of the electroformed composite member during electroforming.

Examples of the invention

The following examples are merely exemplary and should not be construed as limiting the scope of the claimed invention in any way. All ingredients are available from common chemical suppliers unless otherwise indicated.

Electroforming of nickel/alumina nanocomposites was demonstrated in nickel sulfamate-based electroforming bath chemistry using boehmite particles with an average size of about 50 nm. The bath is composed of about 300 g/L nickel sulfamate Ni (SO) ₃ NH ₂ ) ₂ 30 g/L of NiCl ₂ 60 g/L of boric acid H ₃ BO ₃ A composition wherein 50 g/L of 50 nm boehmite particles are added to form a suspension. The total volume of 2L was mixed and heated to 60 ℃ while continuously stirring in an ultrasonic water bath using an overhead stirrer. The activated nickel anode and stainless steel cathode were immersed in the bath and applied at 50 mA/cm ² For 20 hours to create a sample of about 0.5 mm thickness, measured as 2 cm wide by 5 cm long. The micrograph in figure 4 shows the material structure of a typical sample-a polycrystalline nickel matrix containing darker boehmite particles. The material structure shown in fig. 4 includes about 3% to 4% (by area) of 50 nm boehmite particles in a range as depositedA polycrystalline nickel matrix deposited on the cathode. The particles inherently strengthen the electroformed composite member by inhibiting dislocation motion and stabilizing the fine grain structure. The hot hardness test showed benefits over a pure nickel reference sample (representing the current state of the art). Fig. 6 shows the vickers hardness (Hv) in GPa for the material structure of fig. 4. Further performance improvements may be achieved by improving dispersibility (including finer particles), increasing particle volume fraction, or using other particle types.

The as-deposited structure of fig. 4 may be subjected to an optional thermal treatment to convert the boehmite into other more stable, harder alumina forms. Although the conversion of boehmite to various alumina phases is known and well documented in the ceramics world, the conversion of boehmite as a reinforcing particle to a metal matrix composite material produced by electroforming is a new practice and fig. 5 is a micrograph of the structure obtained by heat treating the as-deposited structure of fig. 4 at 650 ℃ (1200 ° F) for four hours.

The first transformation of boehmite occurs in the vicinity of 500-550 c. By reacting 2AlO (OH) → gamma-Al ₂ O ₃ + H ₂ Conversion of O, boehmite into gamma-alumina (gamma-Al) ₂ O ₃ ). The water produced by the reaction may be H ₂ OH and H ₂ O, and can be extracted from the material using vacuum heat treatment. As shown in fig. 5, the heat-treated structure has a particle morphology slightly different from the as-deposited structure of fig. 4. Some merging and smoothing may occur during the transition.

Further heat treatment of the structure shown in fig. 5 at higher temperatures, e.g. 1100 ℃ (2010F), may result in γ -Al ₂ O ₃ Conversion to other phases, including, in order, delta, theta and final alpha-alumina (alpha-Al) ₂ O ₃ ) This is the most stable and rigid form. gamma-Al ₂ O ₃ To alpha-Al ₂ O ₃ Results in a greater than 10% reduction in volume of the reinforcing particle. This can increase the strengthening effect of the particles by introducing local strain fields in the material that further interact with and impede the motion of dislocations. Intermediate delta and/or theta phasesIt is also possible to provide more than gamma-Al ₂ O ₃ And the precise heat treatment can be adjusted to adjust the composite strength, ductility, and other properties resulting from particle transformation.

Although the examples disclose the use of boehmite as a suitable precursor, other precursor materials may be used depending on the reinforcing phase desired in the final composite material. For example, yttrium hydroxide (Y (OH) ₃ ) Forming a composite structure. Other reinforcement materials disclosed herein include cerium oxide particles, silica particles, silicon carbide particles, titanium oxide particles, titanium carbide particles, titanium nitride particles, zirconium carbide particles, carbon nanotubes, graphene, or combinations. Any precursor of one or more reinforcing materials that is stable and readily dispersed in the electroforming solution may be used.

As disclosed herein, forming an electroformed composite member may be accomplished by using an electrolyte solution that is surfactant-free and/or dispersant-free. Thus, the electrolyte solution may or may not consist essentially of the metal salt and the precursor. Although other elements or compounds, including surfactants and/or dispersants, may be present in the electrolyte solution, this level should be in excess of trace or non-major levels in order to avoid increasing residual stress in the component when it is formed up to and beyond, for example, 0.5 mm, and/or to limit maximum use temperatures to, for example, below 500 ° F, and/or to limit other mechanical properties (e.g., UTS) to below 100 ksi.

Other aspects of the invention are provided by the subject matter of the following clauses:

1. a method of forming an electroformed composite member comprising reinforcing particles in a metal matrix, the method comprising passing an electric current between an anode and a cathode in the presence of an electrolyte, wherein the electrolyte comprises a metal salt and a plurality of reinforcing particle precursors; and depositing a composite layer on the cathode, wherein the composite layer comprises a metal matrix and a plurality of reinforcing particle precursors dispersed in the metal matrix.

2. The method according to any preceding clause, further comprising subjecting the electroformed component to a first heat treatment to convert the reinforcing particle precursor into a more stable phase of the reinforcing particles.

3. The method according to any preceding clause, wherein the first heat treatment is performed in vacuum.

4. The method according to any preceding clause, further comprising performing a second heat treatment after the first heat treatment to transform the reinforcing phase particles into another phase.

5. The method according to any preceding clause, wherein the second heat treatment is performed at a higher temperature than the first heat treatment.

6. The method according to any preceding clause, wherein the first heat treatment comprises heating the electroformed component at a temperature equal to or greater than the transition temperature of the reinforcing particle precursor for a time sufficient to complete the transition of the reinforcing particle precursor to the more stable phase of the reinforcing particles.

7. The method of any preceding clause, wherein the metal salt comprises a salt of nickel, copper, cobalt, or a combination thereof.

8. The method according to any preceding clause, wherein the reinforcing particle precursor comprises a hydroxide precursor of the reinforcing particles.

9. The method of any preceding clause, wherein the plurality of reinforcement particle precursors comprises precursors of alumina particles, yttria particles, alumina fibers, ceria particles, silica particles, titania particles, or combinations thereof.

10. The method according to any preceding clause, wherein the plurality of reinforcing particle precursors comprises an aluminum hydroxide material, a yttrium hydroxide material, a cerium hydroxide material, a silicon hydroxide material, a titanium hydroxide material, or a combination thereof.

11. The method according to any preceding clause, wherein the reinforcing particle precursor has an average particle size of less than about 100 nanometers.

12. The method according to any preceding clause, wherein the volume fraction of the plurality of reinforcing particles in the composite layer is in a range from about 2 vol% to about 10 vol%.

13. The method according to any preceding clause, wherein the mean free path between the plurality of reinforcing particle precursors is in the range from about 5 nanometers to about 1000 nanometers.

14. The method according to any preceding clause, wherein the composite layer comprises a nickel-based matrix, and the reinforcing particle precursor comprises one or more of alumina particles, yttria particles, alumina fibers, or a combination thereof dispersed in the nickel-based matrix.

15. The method according to any preceding clause, wherein the composite layer comprises a nickel-based matrix and a plurality of boehmite particles dispersed in the nickel-based matrix.

16. A method according to any preceding clause, including depositing the electroformed member on a mandrel to have a desired average thickness from about 0.5 millimeters to about 5 millimeters.

17. The method according to any preceding clause, wherein the electroformed component is a component of an aircraft engine.

18. The method of any preceding clause, wherein the electroformed component comprises an aircraft engine transport component, a pipe, a conduit, a seal, a blade, an airfoil, a strut, a liner, a shell, a flow path structure, a leading edge, a bracket, a flange, a casing.

19. A method according to any preceding clause, wherein the electroformed member has a use temperature capability greater than 500 ° F.

20. A method according to any preceding clause, wherein the electroformed component has a use temperature capability equal to or greater than 1200 ° F.

21. An electroformed component formed using the method of any preceding clause.

The appended claims are intended to protect the invention as broadly as it has been conceived and the examples presented herein illustrate embodiments selected from a collection of all possible embodiments. Accordingly, it is applicants' intention that the appended claims are not to be limited by the choice of examples utilized to illustrate features of the present disclosure. As used in the claims, the word "comprise" and grammatical variations thereof also logically encompasses and includes variations and varying degrees of phrase such as, for example and without limitation, "consisting essentially of" and "consisting of. Ranges are provided as necessary; these ranges include all subranges therebetween. It is intended that such changes in scope will suggest themselves to those skilled in the art, and where possible should be construed to be covered by the appended claims without also contributing to the public. It is also expected that advances in science and technology will make equivalents and substitutions possible that are not now contemplated due to the imprecision of language and these variations should also be construed where possible to be covered by the appended claims.

Claims

1. A method of forming an electroformed composite member comprising reinforcing particles in a metal matrix, the method comprising:

passing an electric current between the anode and the cathode in the presence of an electrolyte, wherein the electrolyte comprises a metal salt and a plurality of reinforcing particle precursors, the reinforcing particle precursors comprising AlO (OH);

depositing a composite layer on the cathode, wherein the composite layer comprises the metal matrix and a plurality of reinforcement particle precursors dispersed in the metal matrix;

subjecting the electroformed composite member to a first thermal treatment to convert the reinforcing particle precursor to a more stable phase of the reinforcing particles, the more stable phase of the reinforcing particles comprising gamma-Al ₂ O ₃ (ii) a And

comprising performing a second heat treatment after the first heat treatment to transform the reinforcing particles into other phases, comprising delta-Al in sequence ₂ O ₃ 、θ-Al ₂ O ₃ And final alpha-Al ₂ O ₃ ；

Wherein the mean free path between the plurality of reinforcing particle precursors is in a range from 5 nanometers to 1000 nanometers.

2. The method of claim 1, wherein the first heat treatment is performed in vacuum.

3. The method of claim 1, wherein the second heat treatment is performed at a higher temperature than the first heat treatment.

4. The method of claim 1, wherein the first thermal treatment comprises heating the electroformed composite member at a temperature equal to or greater than the transition temperature of the reinforcing particle precursor for a time sufficient to complete the transition of the reinforcing particle precursor to a more stable phase of the reinforcing particles.

5. The method of any one of claims 1 to 4, wherein the metal salt comprises a salt of nickel, copper, cobalt, or a combination thereof.

6. The method of any of claims 1-4, wherein the average particle size of the reinforcing particle precursor is less than 100 nanometers.

7. The method of any of claims 1 through 4, wherein the volume fraction of the plurality of reinforcing particles in the composite layer is in a range from 2 vol% to 10 vol%.

8. The method of any of claims 1 to 4, wherein the composite layer comprises a nickel-based matrix and the reinforcing particle precursor comprises AlO (OH) particles dispersed in the nickel-based matrix.

9. The method of any of claims 1 to 4, comprising depositing the electroformed composite member on a mandrel to have a desired average thickness from 0.5 millimeters greater to 5 millimeters greater.

10. The method of any one of claims 1 to 4, wherein the electroformed composite component comprises an aircraft engine transport component, a pipe, a conduit, a seal, a blade, an airfoil, a strut, a liner, a shell, a flow path structure, a leading edge, a bracket, a flange, a casing.

11. The method of any one of claims 1 to 4, wherein the electroformed composite member has a use temperature capability of greater than 500 degrees Fahrenheit.

12. The method of any one of claims 1 to 4, wherein the electroformed composite member has a use temperature capability equal to or greater than 1200 ° F.

13. An electroformed composite component formed using the method of any one of claims 1-12.