Carbon fiber reinforced plastic molded body with metal-containing coating

Abstract

To provide a molded product in which a densely and firmly adhered metal-containing coating is formed on a carbon fiber-reinforced plastic composite material, and to provide a thunder-resistant material made of the molded product.SOLUTION: There is provided: a molded product formed with a metal-containing coating made of a metal-particle metal and a polyarylene ether ketone (PAEK) resin by projecting metal particles and a polyarylene ether ketone (PAEK) resin particulate matter to at least part of a surface of a carbon fiber-reinforced plastic with a cold spray method; and a thunder-resistant material made of the molded product.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a carbon fiber reinforced plastic molded body having a metal-containing film.

Background Art

[0002] Composite materials such as carbon fiber reinforced plastics (CFRP) are lightweight and high-strength, and thus are widely used as structural members for aircraft, automobiles, ships, etc. Since such carbon fiber reinforced plastics contain a resin with low conductivity as a matrix, for example, when used as an aircraft wing structure, it is necessary to impart conductivity to the surface in order to provide lightning resistance. As a method for imparting conductivity to the surface of a composite material, a method of exposing a copper foil on the surface of a composite material by heat-bonding and molding a copper foil simultaneously with the molding of the composite material is known (for example, see Patent Document 1). However, the above method of simultaneously heat-bonding and molding a copper foil on the surface of a composite material has a problem of poor adhesion because it bonds a resin and a copper foil having significantly different thermal expansion coefficients.

[0003] Therefore, in order to make the surface of a composite material conductive, a method of producing a metal film by directly spraying metal particles onto the composite material by a cold spray method is known (for example, Patent Documents 2 and 3).

[0004] On the other hand, as an attempt to improve the adhesion of a metal film to CFRP, in Non-Patent Document 1, studies have been conducted on cold spraying with Cu particles mixed with PEEK.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Patent Document 3

Non-Patent Documents

[0006] [Non-Patent Document 1] V. Bortolussi, F. Borit, A. Chesnaud, M. Jeandin, Evry / F, M. Faessel, B. Figliuzzi, F. Willot, Fontainebleau / F,K. Roche, G. Surdon, Argenteuil / F:Cold spray of metal-polymer composite e coatings ontocarbon fiber-reinforced polymer (CFRP) International Thermal Spray Conference 2016 (ITSC 2016), DVS, May 20 16, Shanghai, China. 7 p. hal-01337696 [Overview of the project] [Problems that the invention aims to solve]

[0007] Patent Document 2 describes a method of cold spraying non-spherical irregularly shaped particles onto a composite material, and Patent Document 3 describes a method of cold spraying relatively large metal particles of 10 μm or more onto a composite material. However, in the cold spraying methods for forming metal films described in these documents, there are cases where the adhesion between the metal and the composite material is insufficient. For example, when the metal film is formed by scattering it on the composite material, some of it may fall off due to interfacial delamination.

[0008] Furthermore, the metal particles used in these studies, depending on their shape and size, can increase the kinetic energy of the metal particles during cold spraying. Depending on the structure and composition of the carbon fiber reinforced plastic used, this can lead to problems such as the resin being scraped, or even the carbon fibers themselves being broken or cut.

[0009] Non-patent document 1 describes an attempt to improve the adhesion of metal films to CFRP by mixing Cu particles with PEEK and cold spraying them. However, in this non-patent document 1, relatively large spherical Cu particles of 10 μm or more are mixed with PEEK powder, and the mixed powder is projected onto the CFRP using a high-pressure cold spray device with a pressure of 1 MPa or more. As a result, there were problems such as damage to the CFRP surface as a substrate and partial peeling of the metal-containing film once it had been formed.

[0010] Therefore, in view of the background of the prior art, the object of the present invention is to provide a molded article having a dense and firmly adhered metal-containing film formed on a carbon fiber reinforced plastic composite material, and a lightning protection material made from the molded article. [Means for solving the problem]

[0011] To solve the above problems, the present invention mainly has the following configuration. [1] A molded article characterized in that a metal-containing coating is formed on at least a portion of the surface of a carbon fiber reinforced plastic by projecting metal particles and polyarylene ether ketone (PAEK) resin powder by a cold spray method, the coating consisting of the metal of the metal particles and the polyarylene ether ketone (PAEK) resin. [2] The molded article according to [1], wherein the particle size of the metal particles is 0.1 μm or more and less than 10 μm. [3] The molded article according to [1] or [2], wherein the metal particles are spherical. [4] The molded article according to any one of [1] to [3], wherein the metal particles consist of at least one selected from Cu, Sn, Ti, and Al. [5] The molded article according to any one of [1] to [4], wherein the metal-containing film is scattered on the carbon fiber reinforced plastic. [6] The molded article according to [5], wherein the scattered metal-containing coatings are in the shape of minute protrusions. [7] The molded article according to any one of [1] to [6], wherein the metal-containing film and the carbon fiber-reinforced plastic are bonded via oxygen atoms or carbon atoms. The molded article according to any one of [1] to [7], wherein the matrix resin of the carbon fiber reinforced plastic contains a thermosetting resin. The molded article according to any one of [1] to [7], wherein the matrix resin of the carbon fiber reinforced plastic contains a thermoplastic resin. A lightning protection material comprising the molded article according to any one of [1] to [9].

Advantages of the Invention

[0012] According to the present invention, a molded article in which metal particles and polyarylene ether ketone (PAEK) resin powder particles are projected onto the surface of a carbon fiber reinforced plastic by a cold spray method to form a metal-containing film has a high adhesion strength of the metal-containing film to the carbon fiber reinforced plastic, and the molded article can be made conductive by the densely formed metal-containing film. Therefore, it can be expected to be suitably used as a lightning protection material for aircraft, automobiles, and wind turbines.

Brief Description of the Drawings

[0013] [Figure 1] It is a cross-sectional SEM photograph of the molded article in Example 1 of the present invention. [Figure 2] It is a photograph of the surface of the molded article in Example 7 of the present invention taken with a digital camera. [Figure 3] It is a photograph of the surface of the molded article in Example 8 of the present invention taken with a digital camera.

Modes for Carrying Out the Invention

[0014] Hereinafter, the present invention will be described in detail together with embodiments. The molded article according to the present invention is formed by forming a metal-containing film on at least a part of the surface of a carbon fiber reinforced plastic, and is characterized in that metal particles and polyarylene ether ketone (PAEK) resin powder particles are projected by a cold spray method to form a metal-containing film.

[0015] As the carbon fiber in the present invention, for example, PAN-based carbon fiber made from polyacrylonitrile (PAN) fiber as a raw material, pitch-based carbon fiber made from petroleum tar or petroleum pitch as a raw material, cellulose-based carbon fiber made from viscose rayon, acetic acid cellulose, etc. as a raw material, vapor-grown carbon fiber made from hydrocarbons, etc. as a raw material, and these graphitized fibers, etc. may be mentioned. Among these carbon fibers, PAN-based carbon fiber is preferably used in terms of excellent balance between strength and elastic modulus. In addition to carbon fiber, other reinforcing fibers can also be used in combination according to the purpose. The type of reinforcing fiber to be used in combination is not particularly limited, and examples include inorganic fibers, metal fibers, organic fibers, etc. Two or more of these may be used.

[0016] Examples of the metal fiber include fibers made of metals such as iron, gold, silver, copper, aluminum, brass, and stainless steel.

[0017] Examples of the organic fiber include fibers made of organic materials such as aramid, polybenzoxazole (PBO), polyphenylene sulfide, polyester, polyamide, and polyethylene. Examples of the aramid fiber include para-aramid fiber excellent in strength and elastic modulus, and meta-aramid fiber excellent in flame retardancy and long-term heat resistance. Examples of the para-aramid fiber include polyparaphenylene terephthalamide fiber, copolyparaphenylene-3,4'-oxydiphenylene terephthalamide fiber, etc., and examples of the meta-aramid fiber include polymetaphenylene isophthalamide fiber, etc. As the aramid fiber, para-aramid fiber having a higher elastic modulus than meta-aramid fiber is preferably used.

[0018] Inorganic fibers include, for example, fibers made from inorganic materials such as glass, basalt, silicon carbide, and silicon nitride. Examples of glass fibers include E glass fibers (for electrical use), C glass fibers (for corrosion resistance), S glass fibers, and T glass fibers (high strength, high modulus). Basalt fibers are made by fibrousizing the mineral basalt and are extremely heat-resistant fibers. Basalt generally contains 9-25% by weight of iron compounds FeO or FeO2 and 1-6% by weight of titanium compounds TiO or TiO2, but it is also possible to increase the amount of these components in the molten state and then fibrousize them.

[0019] The carbon fibers used in this invention are typically composed of one or more carbon fiber bundles, each bundled with a large number of individual fibers. When one or more carbon fiber bundles are arranged, the number of individual fibers in one carbon fiber bundle is preferably 500 to 50,000. From the viewpoint of handling, the number of individual fibers in the carbon fiber is more preferably 1,000 to 50,000, even more preferably 1,000 to 40,000, and particularly preferably 1,000 to 30,000. The upper limit of the number of individual fibers in the carbon fiber should be determined while considering the balance between quality and handling, such as voids and dispersibility, as long as good dispersibility and handling are maintained.

[0020] A single carbon fiber bundle is preferably composed of 500 to 50,000 single carbon fibers, each having an average diameter of 5 to 10 μm.

[0021] In the carbon fiber reinforced plastics of the present invention, thermosetting resins and thermoplastic resins are preferably used as the matrix resin.

[0022] Examples of thermosetting resins used in the present invention include epoxy resins, benzoxazine resins, vinyl ester resins, unsaturated polyester resins, urethane resins, phenolic resins, melamine resins, maleimide resins, cyanate ester resins, and urea resins. Among these, epoxy resins, benzoxazine resins, vinyl ester resins, unsaturated polyester resins, phenolic resins, and mixtures thereof have high mechanical properties and are therefore preferably used. In particular, epoxy resins are especially preferred because they have excellent mechanical properties and also have excellent adhesion to carbon fibers.

[0023] As epoxy resins, compounds having multiple epoxy groups in their molecules are used. Suitable epoxy resins include, for example, bisphenol A type epoxy resin, bisphenol AD ​​type epoxy resin, bisphenol S type epoxy resin, bisphenol F type epoxy resin, novolac type epoxy resin, naphthalene type epoxy resin, epoxy resins made from copolymers of phenol compounds and dicyclopentadiene, naphthalene type epoxy resins, glycidyl ether type epoxy resins such as novolac type epoxy resin, glycidylamine type epoxy resin, and combinations of these resins.

[0024] Examples of thermoplastic resins used in the present invention include polyesters such as polyethylene terephthalate (PET) resin, polybutylene terephthalate (PBT) resin, polytrimethylene terephthalate (PTT) resin, polyethylene naphthalate (PEN) resin, and liquid crystal polyester resin; polyolefins such as polyethylene (PE) resin, polypropylene (PP) resin, and polybutylene resin; styrene-based resins; as well as polyoxymethylene (POM) resin, polyamide (PA) resin, polycarbonate (PC) resin, polymethylene methacrylate (PMMA) resin, polyvinyl chloride (PVC) resin, polyphenylene sulfide (PPS) resin, polyphenylene ether (PPE) resin, modified PPE resin, and polyimide (PI) resin. Fluorine-based resins such as polyamide-imide (PAI) resin, polyetherimide (PEI) resin, polysulfone (PSU) resin, modified PSU resin, polyethersulfone resin, polyketone (PK) resin, polyarylene etherketone (PAEK) resin, polyarylate (PAR) resin, polyethernitrile resin, phenolic resin, phenoxy resin, and polytetrafluoroethylene resin, as well as thermoplastic elastomers such as polystyrene resin, polyolefin resin, polyurethane resin, polyester resin, polyamide resin, polybutadiene resin, polyisoprene resin, and fluorine-based resin, and copolymers and modified versions thereof can be used, and these may also be resins blended from two or more types. In particular, from the viewpoint of heat resistance and long-term durability, polyphenylene sulfide resin, polyarylene etherketone resin, polyetherimide resin, polyethersulfone resin, and liquid crystal polymer resin are more preferred.

[0025] Examples of the polyarylene ether ketone (PAEK) resin include polyether ketone (PEK) resin, polyether ether ketone (PEEK) resin, polyether ether ketone ketone (PEEKK) resin, polyether ketone ketone (PEKK) resin, low viscosity polyarylene ether ketone (LM-PAEK) resin, polyether ketone ether ketone ketone (PEKEKK) resin, polyether ether ketone ether ketone (PEEKEK) resin, polyether ether ether ketone (PEEEK) resin, and polyether diphenyl ether ketone (PEDEK) resin. These may also be copolymers, modified versions, or blends of two or more resins.

[0026] The metal particles used in this invention are not particularly limited in shape; non-spherical irregularly shaped particles such as dendritic particles, or spherical particles can be used. Spherical particles are particularly preferred because they facilitate the formation of a dense and uniform metal-containing film on carbon fiber reinforced plastic. Here, spherical particles refer to particles in which, for example, the short and long axes of 50 particles arbitrarily extracted from a 2,000x magnification observation image using an SEM (scanning electron microscope) are measured, the long axis / short axis ratio is calculated, and the average value of these values ​​is within the range of 1 to 1.5.

[0027] Furthermore, the particle size of the metal particles is preferably 0.1 μm or larger and less than 10 μm. If the particle size is 10 μm or larger, the kinetic energy becomes a problem, potentially damaging the carbon fibers on the surface of the carbon fiber reinforced plastic or within it. The particle size of the metal particles is preferably in the range of 0.5 μm to 7 μm, and more preferably 1 to 5 μm. Here, the particle size of the metal particles is determined as the weight-average particle size, which is calculated based on the weight-average diameter, which is determined based on the diameter distribution measured according to a conventional method using a laser diffraction particle size distribution analyzer.

[0028] There are no particular limitations on the type of metal used in the metal particles in this invention, but Cu, Al, Ti, Ag, Ni, Zn, Sn, Mo, Fe, Ta, Nb, Si, Cr, and their alloys are preferably used. Among these, Cu, Sn, Ti, and Al are more preferably used from the viewpoint of affinity with carbon fiber reinforced plastics and ease of film formation.

[0029] Furthermore, a metal-containing film can be formed on carbon fiber reinforced plastic by cold spraying using multiple metals. In this case, multiple metals can be mixed and cold sprayed simultaneously, or multiple metals can be cold sprayed separately to sequentially layer the metal-containing film. When sequentially layering metal-containing films, a relatively soft first metal layer is first deposited on the carbon fiber reinforced plastic, and then a relatively hard second metal layer is deposited, thereby forming a metal-containing film in which the second layer is physically strongly bonded to the first layer. Depending on the purpose, three or more layers may be laminated.

[0030] For example, new findings have shown that relatively soft metals such as Sn can penetrate carbon fiber reinforced plastic when cold-sprayed. Furthermore, by cold-spraying another metal, such as Cu, which is harder than Sn, on top of the Sn layer, the Sn layer becomes an adhesive anchor coat layer with the carbon fiber reinforced plastic, and a Cu layer that can be firmly bonded can be reliably formed on that anchor coat layer.

[0031] The metal-containing coating of the molded article of the present invention is formed by projecting metal particles and polyarylene ether ketone (PAEK) resin powders using a cold spray method.

[0032] The cold spray method is a type of thermal spraying technology in which a gas heated to a temperature lower than the melting point or softening temperature of metal particles (approximately 200-900°C) is transformed into a supersonic flow through a tapered, wide-ended nozzle. Metal particles are then introduced into this flow, accelerated, and collide with the substrate at high speed while still in a solid state to form a coating.

[0033] Helium, nitrogen, and air are used as working gases, but air is preferred when considering safety and cost. A working gas pressure of 1 MPa or higher is called the high-pressure cold spray method, and one of the pressures of less than 1 MPa is called the low-pressure cold spray method. These can be used appropriately depending on the purpose, but when projecting metal particles onto carbon fiber reinforced plastic, it is preferable to apply the low-pressure cold spray method to minimize erosion wear on the carbon fiber reinforced plastic. The gas pressure is preferably 0.1 MPa or higher and 0.9 MPa or lower, and more preferably 0.3 MPa or higher and 0.6 MPa or lower.

[0034] In the cold spray method, the kinetic energy of metal particles causes them to plastically deform and begin forming a coating. The speed at which this coating begins to form is called the critical velocity. This critical velocity varies depending on the materials of the metal particles and substrate, as well as the particle size.

[0035] The cold spray method has several advantages: it minimizes oxidation and thermal degradation of the coating, forms a dense coating, has high adhesion to the substrate, and allows for the creation of thick films due to the high efficiency of metal particle adhesion.

[0036] The spraying conditions for cold spray should be adjusted according to the type of metal particles and substrate, by appropriately selecting the gas temperature, gas pressure, and distance between the nozzle and the substrate.

[0037] The metal-containing coating of the present invention is formed by projecting metal particles and polyarylene ether ketone (PAEK) resin powders by a cold spray method, but the projection method is not limited. For example, PAEK resin powders may be projected onto carbon fiber reinforced plastic first, and then metal particles may be projected on top of that, or metal particles may be projected first, and then PAEK resin may be projected on top of that. Furthermore, it is also preferable to pre-mix the metal particles and PAEK resin powders before projecting them onto the surface of the carbon fiber reinforced plastic.

[0038] PAEK resin has a high heat resistance temperature among engineering plastics and is excellent in mechanical strength, durability, hot water resistance, chemical resistance, and radiation resistance, making the carbon fiber reinforced plastic with a metal-containing coating of the present invention suitable for use as a lightning protection material in aircraft and the like.

[0039] There are no particular limitations on the PAEK resin to be projected, but polyether ketone (PEK) resin, polyether ether ketone (PEEK) resin, polyether ether ketone ketone (PEEKK) resin, polyether ketone ketone (PEKK) resin, low viscosity polyarylene ether ketone (LM-PAEK) resin, polyether ketone ether ketone ketone (PEKEKK) resin, polyether ether ketone ether ketone (PEEKEK) resin, polyether ether ether ketone (PEEEK) resin, and polyether diphenyl ether ketone (PEDEK) resin are preferably used, and copolymers, modified versions thereof, and resins blended from two or more types may also be used.

[0040] There are no particular limitations on the form of the PAEK resin powder, but it is preferable to have a particle shape for ease of projection using a cold spray device. The particle size of the PAEK resin is preferably 1 μm or more and less than 100 μm. More preferably 5 μm to 70 μm, and even more preferably 10 μm to 50 μm.

[0041] Here, the particle size of the metal particles is determined as the weight-average particle size, which is calculated based on the weight-average diameter, which is determined from the diameter distribution measured according to a standard method using a laser diffraction particle size distribution analyzer.

[0042] It is preferable that the granular material consisting of metal particles and PAEK resin is mixed in a solid state before being introduced into the cold spray device, and more preferably, that it is uniformly mixed in a dry state. When the metal particles and PAEK resin are uniformly mixed in a solid state before being introduced into the cold spray device in this way, the difference in arrival time between the granular material consisting of metal particles and PAEK resin during projection in the cold spray device can be eliminated or made extremely small, making it possible to efficiently form the desired metal-containing film.

[0043] In the metal-containing film formed on carbon fiber reinforced plastic according to the present invention, there are no particular limitations on the composition ratio of metal to PAEK resin in the film, and the higher the proportion of metal, the better the properties of the metal-containing film, such as conductivity. From the viewpoint of achieving both high conductivity and adhesion to carbon fiber reinforced plastic, the proportion of PAEK resin in the metal-containing film is preferably 10 wt% or less, more preferably 5 wt% or less, and even more preferably 3 wt% or less. There are no particular limitations on the lower limit, but it is preferably 0.1 wt% or more.

[0044] The shape of the metal-containing coating on the carbon fiber reinforced plastic can vary depending on the purpose, such as being formed as a film, or as a grid or mesh. However, in the present invention, the metal-containing coating is preferably scattered on the carbon fiber reinforced plastic. Unlike grid or mesh forms, scattered means that the majority of the metal-containing coating is not connected, for example, in a dot-like manner, but rather exists discretely on the carbon fiber reinforced plastic, each independently scattered. Because the metal-containing coatings are scattered, for example, when the molded body of the present invention is used as a lightning protection material for an aircraft, when struck by lightning, the lightning can be dispersed and absorbed by each of the scattered metal-containing coatings on the carbon fiber reinforced plastic, thereby reducing the damage to the molded body from the lightning strike. Furthermore, since less metal is used compared to the case of grid or mesh forms, the weight of the aircraft can be reduced when used as a lightning protection material.

[0045] Furthermore, the metal-containing coating of the present invention is preferably in the form of micro-protrusions. Micro-protrusions refer to small protrusions that are arranged at relatively equal intervals on the carbon fiber reinforced plastic. The shape of the protrusions is not particularly limited, but examples include cylindrical, conical, square pyramidal, triangular pyramidal, frustum of a cone, frustum of a square pyramidal, and frustum of a triangular. The size of the micro-protrusions is preferably 1 to 500 μm in diameter and side length, more preferably 10 to 200 μm, and even more preferably 30 to 100 μm.

[0046] In the present invention, it is preferable that the metal-containing film is bonded to the carbon fiber reinforced plastic via oxygen atoms or carbon atoms. Bonding of oxygen atoms or carbon atoms to the metal or the resin or carbon fibers of the carbon fiber reinforced plastic improves the adhesion between the formed metal-containing film and the carbon fiber reinforced plastic, resulting in superior practical durability. Regarding the bonding between oxygen atoms or carbon atoms and the metal or carbon fiber reinforced plastic, the bond may be created by using a cold spray method to project the metal onto the carbon fiber reinforced plastic, causing a chemical reaction at the interface between the two. Alternatively, the bond may be created by pre-treating the surface of the carbon fiber reinforced plastic with a laser, plasma, or corona discharge to activate it.

[0047] Furthermore, by sanding or laser-grooving the surface of carbon fiber reinforced plastic and then cold-spraying metal particles onto it, a bond is created through mechanical interlocking, thereby increasing the adhesion strength between the carbon fiber reinforced plastic and the metal-containing coating.

[0048] The molded article formed by forming a metal-containing coating on carbon fiber reinforced plastic according to the present invention has high conductivity and excellent adhesion strength, making it suitable for use as a lightning protection material for structures that are damaged by lightning strikes, such as aircraft, automobiles, urban air mobility (UAMs), and wind turbines. [Examples]

[0049] The present invention will be further described below with reference to examples, but the present invention is not limited to these examples. Characterization of each example and comparative example was carried out according to the following methods.

[0050] 1. SEM-EDX (Scanning Electron Microscope - Energy Dispersive X-ray Spectroscopy) The molded body, which had a metal-containing coating formed after cold spraying, was embedded in embedding epoxy resin and cured at room temperature for 24 hours. The cross-section of the molded body was then polished, and the polished surface was photographed at a magnification of 2,000x using SEM-EDX (manufactured by Hitachi High-Technologies Corporation) for line analysis.

[0051] [Base material] In the examples and comparative examples, the carbon fiber reinforced plastic substrates used were those shown below.

[0052] (Base material 1) CFRP sheet manufactured by Toray Industries, Inc., using epoxy resin as the thermosetting resin (made by laminating aircraft-grade epoxy prepreg material in a pseudo-isotropic manner and then autoclave molding).

[0053] (Base material 2) A laminate of thermoplastic UD tape (UD: unidirectional) manufactured by Toray Advanced Composites, using LM-PAEK as the thermoplastic resin ("TC1225" is a pseudo-isotropic laminate that has been press-molded).

[0054] [Metal particles] In the examples and comparative examples, the projected metal particles and polyarylene ether ketone (PAEK) resins were as follows.

[0055] (particle 1) Spherical copper particles ("Cu-HWQ": average particle size 5 μm) manufactured by Fukuda Metal Foil & Powder Industry Co., Ltd.

[0056] (particle 2) Spherical copper particles ("Cu-HWQ": average particle size 3μm) manufactured by Fukuda Metal Foil & Powder Co., Ltd.

[0057] (Resin 1) PEEK resin (VESTAKEEP 2000UFP20, average particle size: 20μm) manufactured by DAICEL EVONIC.

[0058] (Resin 2) PEEK resin (VESTAKEEP 2000FP, average particle size: 50μm) manufactured by DAICEL EVONIC.

[0059] (Resin 3) Manufactured by VICTREX, LM-PAEK resin (AE250 PWD particle size 25μm)

[0060] [Example 1] A pre-mixed mixture of carbon fiber reinforced plastic (substrate 1) was used, consisting of 97 wt% of particle 1 as metal particles and 3 wt% of resin 1 as polyarylene ether ketone (PAEK) resin. The mixed powder of metal particles and resin was projected onto the substrate by cold spraying using an Obninsk Center for Powder Spraying low-pressure cold spray device with a gas temperature of 300°C, a pressure of 0.5 MPa, a feed rate of 30 mm / s, a distance of 20 mm between the nozzle and the substrate, two passes, and feeder setting P1. A cross-sectional photograph (Figure 1) shows that a metal-containing film consisting of Cu particles and PEEK resin was deposited on the substrate, with a thickness of approximately 100 μm. Within the metal-containing film, there were areas where multiple copper particles were linked together and densified, and areas where multiple PEEK resins were linked together and densified, and further, a structure in which copper particles and PEEK resin were intermingled was observed.

[0061] [Example 2] In this experiment, a mixture of metal particles and resin was projected onto a substrate by cold spraying, similar to Example 1, except that 95 wt% of particle 1 was used as the metal particles and 5 wt% of resin 1 was used as the polyarylene ether ketone (PAEK) resin, and the gas temperature was set to 280°C. Similar to Example 1, a metal-containing film was deposited on the substrate, with a thickness of approximately 50 μm. Also similar to Example 1, the metal-containing film contained areas where multiple copper particles were linked together and densified, and areas where multiple PEEK resin particles were linked together and densified, resulting in a structure in which copper particles and PEEK resin were intermingled.

[0062] [Example 3] In the same manner as in Example 2, a mixed powder of metal particles and resin was projected onto the substrate by cold spraying, except that 90 wt% of particle 2 was used as metal particles and 10 wt% of resin 2 was used as polyarylene ether ketone (PAEK) resin. Similar to Example 1, a metal-containing film was deposited on the substrate, with a thickness of approximately 30 μm. Also, similar to Example 1, the metal-containing film contained areas where multiple copper particles were linked together and densified, and areas where multiple PEEK resin was linked together and densified, resulting in a structure in which copper particles and PEEK resin were intermingled.

[0063] [Example 4] In the same manner as in Example 1, a mixture of metal particles and resin was projected onto the substrate by cold spraying, except that Substrate 2 was used as the carbon fiber reinforced plastic, and a pre-mixed mixture of Particle 1 as the metal particles and Resin 2 as the polyarylene ether ketone (PAEK) resin was used. Similar to Example 1, a metal-containing film was laminated on the substrate, deposited to a thickness of approximately 80 μm. Also, similar to Example 1, the metal-containing film contained areas where multiple copper particles were linked together and densified, and areas where multiple PEEK resin was linked together and densified, and furthermore, a structure in which copper particles and PEEK resin were intermingled. Line analysis performed by SEM-EDX and STEM-EDX (scanning transmission electron microscope-energy dispersive X-ray spectrometer) revealed oxygen atoms near the interface between Cu and carbon fiber reinforced plastic in the metal-containing film, suggesting that Cu and carbon fiber reinforced plastic are bonded via oxygen atoms.

[0064] [Example 5] In the same manner as in Example 1, a mixture of metal particles and resin was projected onto the substrate by cold spraying, except that Substrate 1 was used as the carbon fiber reinforced plastic, and a pre-mixed mixture of Particle 1 as the metal particles and Resin 3 as the polyarylene ether ketone (PAEK) resin was used. Similar to Example 1, a metal-containing film was laminated on the substrate, deposited to a thickness of approximately 85 μm. Furthermore, within the metal-containing film, there were areas where multiple copper particles were linked together and densified, and areas where multiple LM-PAEK resins were linked together and densified, resulting in a structure in which copper particles and LM-PAEK resins were intermingled.

[0065] [Example 6] A base material 1 was used as a carbon fiber reinforced plastic, particle 1 as metal particles, and resin 1 as a polyarylene ether ketone (PAEK) resin. First, using only resin 1, resin 1 was cold-sprayed onto the base material using an Obninsk Center for Powder Spraying low-pressure cold spray device with a gas temperature of 280°C, a pressure of 0.5 MPa, a feed rate of 30 mm / s, a distance of 20 mm between the nozzle and the base material, one pass, and feeder setting P1. Subsequently, particle 1 was projected onto the base material under the same conditions, on top of the layer of resin 1 that had been deposited. A molded body was obtained in which a metal-containing film with a two-layer structure was laminated on the base material 1, with PEEK resin laminated on top of that, and then Cu film deposited on top of that.

[0066] [Example 7] A carbon fiber reinforced plastic substrate 1 was used, and a pre-mixed mixture of 97 wt% of particle 1 as metal particles and 3 wt% of resin 1 as polyarylene ether ketone (PAEK) resin was used. An Obninsk Center for Powder Spraying low-pressure cold spray device with a jacketed water cooling system attached to the nozzle was used with a gas temperature of 460°C, a pressure of 0.55 MPa, a feed rate of 15 mm / s, a distance of 20 mm between the nozzle and the substrate, 2 passes, and a feeder setting of P1. A masking plate (made of stainless steel, 120 mm in both length and width, 1 mm thick, with slits of 0.5 mm width, slit pitch interval of 4.5 mm, and 25 slits) was placed on the substrate 1, and the mixed powder of metal particles and resin was projected onto the substrate by cold spraying under the above conditions. The masking plate was then rotated 90°, and the mixed powder was projected again by cold spraying under the same conditions. As a result, a metal-containing film was formed in a grid pattern on the substrate 1, as shown in Figure 2. Within the metal-containing coating of the lattice-like portion, there are areas where multiple copper particles are linked together and densely packed, and areas where multiple PEEK resins are linked together and densely packed, resulting in a structure in which copper particles and PEEK resins are intermingled.

[0067] [Example 8] A masking plate (made of stainless steel, 120 mm in both length and width, 1 mm thick, with 0.5 mm diameter holes, 4.6 mm hole pitch, and a total of 529 holes) was placed on substrate 1, and a mixed powder of metal particles and resin was projected onto the substrate by cold spraying, in the same manner as in Example 7, except that the number of passes was 4. As a result, a metal-containing film was formed on substrate 1 in a dot pattern, as shown in Figure 3. In the metal-containing film of the dot-shaped areas, there were areas where multiple copper particles were linked together and densified, and areas where multiple PEEK resin was linked together and densified, and furthermore, a structure in which copper particles and PEEK resin were mixed together was obtained.

[0068] [Comparative Example 1] Except for not using a projection resin and using only particle 1 as the metal particles, metal particles were projected onto the substrate in the same manner as in Example 1. A Cu coating was deposited on the substrate, but it was deposited to a thickness of approximately 10 μm, and the film formation efficiency could not be sufficiently increased compared to the example.

[0069] [Comparative Example 2] When metal particles were projected onto a substrate in the same manner as in Example 8, except that no projection resin was used and only particle 1 was used as the metal particles, a Cu coating was deposited on the substrate in a dot pattern. However, the adhesion of the Cu coating to the substrate was weak, and when the surface was rubbed by hand, the dot-shaped Cu coating peeled off and fell away.

[0070] Table 1 summarizes the materials and cold spray conditions used in the examples and comparative examples.

[0071] [Table 1] [Industrial applicability]

[0072] The molded article formed by forming a metal-containing film on carbon fiber reinforced plastic according to the present invention has high conductivity, making it suitable as a lightning protection material for aircraft fuselages and wings, lightning protection material for flying cars such as UAMs, and lightning protection material for wind turbines for wind power generation. Furthermore, because the molded article formed by forming a metal-containing film on carbon fiber reinforced plastic according to the present invention has high adhesion between the carbon fiber reinforced plastic and the metal-containing film, it can be applied to general industrial uses such as metal-carbon fiber reinforced plastic bonding materials for reinforcing automobiles, heat dissipation materials for battery cases made of carbon fiber reinforced plastic, and pressure vessels such as metal-carbon fiber reinforced plastics that contain gases such as hydrogen.

Claims

1. A method for manufacturing a molded article, characterized by projecting metal particles with a particle size of 0.1 μm or more and less than 10 μm, and powdered polyarylene ether ketone (PAEK) resin onto at least a portion of the surface of a carbon fiber reinforced plastic using a cold spray method at a pressure of less than 1 MPa to form a metal-containing coating consisting of the metal of the metal particles and the polyarylene ether ketone (PAEK) resin.

2. The method for manufacturing a molded article according to claim 1, wherein the metal particles are spherical.

3. The method for manufacturing a molded article according to claim 1 or 2, wherein the metal particles consist of at least one selected from Cu, Sn, Ti, and Al.

4. A method for manufacturing a molded article according to any one of claims 1 to 3, wherein the metal-containing film is scattered on the carbon fiber reinforced plastic.

5. The method for manufacturing a molded article according to claim 4, wherein the scattered metal-containing coatings have a micro-protrusion shape.

6. A method for manufacturing a molded article according to any one of claims 1 to 5, wherein the metal-containing film and the carbon fiber-reinforced plastic are bonded via oxygen atoms or carbon atoms.

7. A method for manufacturing a molded article according to any one of claims 1 to 6, wherein the matrix resin of the carbon fiber reinforced plastic includes a thermosetting resin.

8. A method for manufacturing a molded article according to any one of claims 1 to 6, wherein the matrix resin of the carbon fiber reinforced plastic includes a thermoplastic resin.

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