Carbon fiber reinforced resin composite material and method for manufacturing the same

Abstract

This invention provides a carbon fiber reinforced polymer (CFRP) composite material that enhances the anchoring effect of the metal layer to the CFRP substrate and improves adhesion. [Solution] The CFRP composite material comprises a base material made of CFRP, a first metal layer laminated on the surface of the base material, and a second metal layer laminated on the surface of the first metal layer. The surface of the base material has carbon fiber cutting grooves formed to a depth in which the carbon fibers in the base material are actually cut, and the first metal penetrates into the grooves and is fixed therein. The manufacturing method includes (1) forming the cutting grooves, (2) laminating the first metal layer by thermal spraying (with penetration into the grooves), and (3) laminating the second metal layer by plating.

Description

[Technical Field]

[0001] The present invention relates to a carbon fiber reinforced resin composite material in which a metal layer is laminated on the surface of a substrate made of carbon fiber reinforced resin (CFRP), and to a method for producing the same. [Background technology]

[0002] In many industrial sectors, carbon fiber reinforced polymer (CFRP) is a useful material used in a wide range of applications. To impart various properties to CFRP depending on the application, various metal layers are laminated (formed) onto the CFRP by methods such as plating, thermal spraying, and vapor deposition. CFRP with these metal layers is then given the necessary properties as a carbon fiber reinforced polymer composite material (CFRP composite material).

[0003] The properties required of CFRP composite materials with a metal layer include wear resistance and impact resistance. To improve wear resistance and impact resistance, good adhesion between the CFRP and the metal layer is important.

[0004] Various efforts are being made to improve the adhesion between CFRP and metal layers in CFRP composite materials. For example, Patent Document 1 discloses a CFRP roller having a copper or nickel undercoat and an outermost hard chromium plating layer on the outer circumference of a CFRP pipe having a recess of a predetermined size. Patent Document 2 discloses a method for preventing carbon fiber detachment from CFRP having exposed carbon fiber portions, characterized by preventing detachment by forming a metal film on the surface of the CFRP. Patent Document 3 discloses a method for manufacturing an article having a plating film on the surface of a CFRP substrate (CFRP composite material), which includes forming an opening from the surface of the CFRP substrate to reach carbon fibers embedded inside the substrate, introducing a conductive material into the opening, and forming a plating film on the surface of the substrate. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 63-259214 [Patent Document 2] Japanese Patent Publication No. 2009-052091 [Patent Document 3] Japanese Patent Publication No. 2021-50387 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] The CFRP roller disclosed in Patent Document 1 involves laminating a metal layer onto a CFRP pipe having a recess of a predetermined size, aiming to improve the adhesion of the metal layer to the CFRP (pipe). However, the recess is limited in shape to the surface of the CFRP pipe, and the state of adhesion with the carbon fibers embedded in the CFRP is unknown, making it difficult to say that sufficient adhesion between the CFRP and the metal layer is ensured.

[0007] Furthermore, the method for preventing carbon fiber detachment from CFRP disclosed in Patent Document 2 prevents detachment of carbon fibers by forming a metal film on the CFRP surface. However, this method merely prevents the detachment of exposed carbon fibers on the CFRP surface, and it cannot be said that it sufficiently ensures essential adhesion between the CFRP and the metal film.

[0008] Furthermore, the CFRP composite material disclosed in Patent Document 3 allows a conductive material to be introduced into openings that reach the carbon fibers formed on the substrate surface, thereby guiding the conductivity of the carbon fibers to the substrate surface side via the conductive material. The openings into which the conductive material is introduced are partially formed to suppress the exposure of carbon fibers and prevent peeling, thereby improving the adhesion between the plating film formed on the substrate surface and the CFRP substrate. However, since the openings are only deep enough to reach the carbon fibers, the anchoring effect of the conductive material introduced into the openings to the CFRP substrate is limited. Therefore, further improvement in the adhesion between the plated film, which is plated via the conductive material, and the CFRP substrate is desirable.

[0009] This invention has been made in view of the above problems, and aims to provide a carbon fiber reinforced resin composite material and a method for manufacturing the same, which have improved adhesion between the metal layer and the carbon fiber reinforced resin substrate. [Means for solving the problem]

[0010] The inventors of this invention have conducted extensive research to solve the above problems and have found that the following invention is suitable for the above purpose, leading to the present invention.

[0011] This invention relates to the following invention. <1> A carbon fiber reinforced resin composite material comprising a base material made of carbon fiber reinforced resin, a first metal layer made of a first metal laminated on the surface of the base material, and a second metal layer made of a second metal laminated on the surface of the first metal layer, wherein the surface of the base material has carbon fiber cutting grooves formed to a depth in which the carbon fibers in the base material are cut, and the first metal constituting the first metal layer penetrates into the interior of the carbon fiber cutting grooves. <2> The first metal penetrates to a depth greater than the exposed position of the cut carbon fibers within the carbon fiber cutting groove, and is fixed to the inner surface of the carbon fiber cutting groove and the exposed carbon fibers. <1> The carbon fiber reinforced resin composite material described above. <3> The first metal fills the inside of the carbon fiber cutting groove. <1> or <2> The carbon fiber reinforced resin composite material described above. <4> The shape of the base material is cylindrical. <1> from <3> A carbon fiber reinforced resin composite material as described in any of the following. <5> The base material is cylindrical in shape, and carbon fiber cutting grooves formed on its outer surface are spirally arranged at approximately equal intervals with respect to the central axis. <4> The carbon fiber reinforced resin composite material described above. <6> The aforementioned substrate consists of a laminate formed by stacking unidirectional carbon fiber materials. <1> from <5> A carbon fiber reinforced resin composite material as described in any of the following. <7> The first metal is a metal selected from the group consisting of Cu, Al, Zn, Ni, or Fe, or an alloy containing these. <1> from <6> A carbon fiber reinforced resin composite material as described in any of the following. <8> The second metal is one of the following: a metal selected from the group consisting of Ni, Cr, Al, or Zn, or an alloy containing these. <1> from <7> A carbon fiber reinforced resin composite material as described in any of the following. <9> The first metal is Cu or a Cu alloy, and the second metal is Ni or Cr. <1> from <8> A carbon fiber reinforced resin composite material as described in any of the following. <10> The surface of the second metal layer further comprises a third layer made of a material harder than the second metal layer. <1> from <9> A carbon fiber reinforced resin composite material as described in any of the following. <11> The third layer is TiN, CrN, or CrAlN. <10> The carbon fiber reinforced resin composite material described above.

[0012] <1a> <1> from <11> A method for manufacturing a carbon fiber reinforced resin composite material as described in any of the above, comprising: (1) forming carbon fiber cutting grooves on the surface of a substrate; (2) thermal spraying the first metal onto the substrate on which the carbon fiber cutting grooves are formed so as to penetrate into the carbon fiber cutting grooves to laminate the first metal layer; and (3) plating the surface of the first metal layer with the second metal to laminate the second metal layer. <2a> The manufacturing method according to <1a>, wherein in step (1), the surface of the substrate is blast-treated before forming the carbon fiber cutting grooves in the substrate. <3a> The manufacturing method according to <1a> or <2a>, wherein the shape of the base material is cylindrical, and the carbon fiber cutting grooves are formed spirally on the circumferential surface of the cylindrical base material. <4a> The manufacturing method according to <3a>, wherein the carbon fiber cutting grooves are formed at substantially equal intervals in the direction of the central axis of the cylindrical substrate, and the density of the carbon fiber cutting grooves in the direction of the central axis of the cylindrical substrate is 1 fiber / cm or more and 30 fiber / cm or less. <5a> The manufacturing method according to any one of <1a> to <4a>, wherein the arithmetic mean roughness (Ra) of the surface of the substrate on which the carbon fiber cutting grooves are formed in step (1) is 3 μm or more and 30 μm or less. The manufacturing method according to any one of <1a> to <5a>, wherein the spraying in step (2) is arc spraying. <7a> The manufacturing method according to any one of <1a> to <6a>, wherein the spraying in step (2) is arc spraying and is carried out at an arc current of 80 A or more and 200 A or less, an arc voltage of 30 V or more and 50 V or less, and a gas pressure of 0.2 MPa or more and 1 MPa or less. <8a> The manufacturing method according to any one of <1a> to <7a>, wherein the plating in step (3) is electrolytic plating and the second metal layer is formed by Ni plating or Cr plating.

Advantages of the Invention

[0013] According to the present invention, there is provided a carbon fiber reinforced resin composite material with improved adhesion of a metal layer to a carbon fiber reinforced resin base material and a method for manufacturing the same.

Brief Description of the Drawings

[0014] [Figure 1] It is a schematic view of the carbon fiber reinforced resin composite material of the present invention and an enlarged view of a part thereof. [Figure 2] It is a cross-sectional view of a groove portion ((a) carbon fiber cutting groove, (b) groove portion not corresponding to the carbon fiber cutting groove). [Figure 3] It is a schematic view of the penetration state of the first metal layer (first metal) into the carbon fiber cutting groove ((a) completely filled inside, (b) partially filled inside). [Figure 4] It is a schematic view of the base material according to the present invention (before step (1), untreated) and an enlarged view of a part thereof. [Figure 5] It is a schematic view of the base material according to the present invention (after step (1)) and an enlarged view of a part thereof. [Figure 6] It is a schematic view of one aspect (cylindrical base material) of the base material according to the present invention (after step (1)). [Figure 7] It is a schematic view of the base material according to the present invention (after step (2)) and an enlarged view of a part thereof. [Figure 8] It is a cross-sectional image of the composite material of Experimental Example 1. [Figure 9] It is a cross-sectional image of the composite material of Experimental Example 1 after step (2). [Figure 10] The images show an overall photograph (top) and a close-up photograph (bottom) of an untreated CFRP roll. [Figure 11] The images show an overall photograph (top) and a close-up photograph (bottom) of a CFRP roll (after groove formation). [Figure 12] The images show an overall photograph (top) and a magnified photograph (bottom) of a CFRP roll (after the Cu thermal spray layer has been formed). [Figure 13] This is a photograph of the appearance of the composite material from Experimental Example 2. [Figure 14] This is a magnified photograph of the surface lamination portion of the composite material in Experimental Example 2. [Figure 15] This is a laser brightness image of the surface of an untreated CFRP roll. [Figure 16] This is a laser brightness image of the surface of a CFRP roll after blasting. [Figure 17] This is a laser brightness image of the surface of a CFRP roll after groove formation. [Modes for carrying out the invention]

[0015] The following describes exemplary embodiments of the present invention. However, this disclosure is not limited to the following embodiments. The drawings are schematic, and the dimensional relationships and proportions of each element may differ from reality. Proportions and other characteristics may also differ between drawings. In all drawings, similar components are denoted by the same reference numerals, and redundant explanations are omitted as appropriate.

[0016] Furthermore, when the expression "~" is used in this specification, it is used to mean an expression that includes the numbers before and after it. In addition, the expression "A and / or B" is used to mean "A only," "B only," or "both A and B."

[0017] <1. Carbon fiber reinforced resin composite material> The present invention relates to a carbon fiber reinforced resin composite material (hereinafter sometimes referred to as "the CFRP composite material of the present invention" or "the composite material of the present invention") having a base material made of carbon fiber reinforced resin, a first metal layer made of a first metal laminated on the surface of the base material, and a second metal layer made of a second metal laminated on the surface of the first metal layer, wherein the surface of the base material has carbon fiber cutting grooves formed to a depth in which the carbon fibers in the base material are cut, and the first metal constituting the first metal layer penetrates into the carbon fiber cutting grooves.

[0018] In the present invention, the "substrate made of carbon fiber reinforced resin" (hereinafter sometimes referred to as "CFRP substrate" or simply "substrate") is a substrate composed of carbon fiber reinforced resin containing carbon fibers and matrix resin. Further details will be described later.

[0019] Furthermore, "carbon fiber reinforced resin composite material" (CFRP composite material) refers to a material that includes a CFRP base material, and in which different materials are integrally combined with the CFRP base material to enhance its properties. In particular, the composite material of the present invention has a structure in which a metal layer is laminated on the surface of the CFRP base material.

[0020] Furthermore, a "carbon fiber cutting groove" refers to a recess formed on the surface of the substrate, where the groove is formed to a depth that actually cuts the carbon fibers embedded in the substrate. More details about carbon fiber cutting grooves will be described later. Furthermore, in this specification, "carbon fiber cutting groove" may be simply referred to as "cutting groove."

[0021] The composite material of the present invention is characterized in that the first metal constituting the first metal layer penetrates into the interior of the cutting groove. The first metal, which constitutes the first metal layer, penetrates into the interior of the cutting groove and fills all or part of the interior of the cutting groove. Furthermore, the penetration of the first metal into the cutting groove reaches a position deeper than the position where the cut carbon fibers are exposed (exposed position) and the first metal that has penetrated into the interior of the cutting groove is fixed to the inner surface (wall and bottom surface) of the cutting groove and to the exposed carbon fibers (including the cut carbon fibers) exposed inside the cutting groove. The penetration and adhesion of the first metal into these cutting grooves creates a mechanical interlocking (anchor effect) at the interface between the metal and the substrate. Specifically, the first metal penetrates into the fine irregularities and pores of the inner surface of the cutting groove 13 (the groove walls and bottom surface, which are mainly composed of the matrix resin 12, and in some cases the sides of carbon fibers exposed in the resin), and adheres to the resin layer by mechanically biting into it. As a result, the metal layer engages firmly with the substrate surface, and its resistance to shear and tensile forces is significantly increased. Consequently, the adhesion between the first metal layer and the substrate is greatly improved.

[0022] Furthermore, the metal constituting the first metal layer reaches the carbon fibers 11 (including the cut end face and side surface) that have actually been cut and exposed within the cut groove, and directly adheres to these exposed carbon fibers. That is, the metal penetrates even into the fine irregularities on the surface of the exposed fibers and in the gaps between the fibers (for example, due to kinetic energy generated during the deposition process by thermal spraying and wetting and spreading effects), and adheres to the fibers themselves in a mechanically interlocking manner. As a result, the carbon fibers that become free ends due to cutting are fixed by the metal, so the reduction in mechanical strength of the surface layer of the substrate caused by fiber cutting can be effectively suppressed.

[0023] It should be noted that "fixation" as used here refers to integration primarily through mechanical interlocking (anchor effect) as described above, and does not necessarily imply the requirement of chemical bonding or metallurgical diffusion bonding. In other words, it refers to an integrated bonding state that is substantially resistant to delamination by shear or tensile forces in the delamination direction at the interface.

[0024] The details of the composite material of the present invention will be described below with reference to the drawings. Figure 1 shows a schematic diagram of the composite material of the present invention and an enlarged view of a part thereof, Figures 2(a) and (b) show cross-sectional views of the cutting groove and the groove portion not corresponding to the cutting groove, and Figures 3(a) and (b) show schematic diagrams of the penetration of the first metal layer into the cutting groove. Note that in Figures 1 to 3, the thickness of the carbon fibers, cutting groove and each layer is exaggerated to facilitate understanding.

[0025] As shown in Figure 1, the composite material 1 of the present invention has as its basic structure a base material 10 made of carbon fiber reinforced resin and a first metal layer 20 and a second metal layer 30 laminated thereon. The respective components will be described in detail below.

[0026] [1-1. Substrate made of carbon fiber reinforced polymer (CFRP)] The base material 10 is a carbon fiber reinforced resin (CFRP) base material (CFRP base material) that includes carbon fibers 11 and resin 12 (matrix resin), and has a structure in which the carbon fibers 11 are embedded in the resin 12.

[0027] The carbon fiber 11 is carbon or a fiber mainly composed of carbon. The type of carbon fiber 11 is not particularly limited, and examples include PAN-based carbon fiber obtained by carbonizing polyacrylonitrile fiber, and pitch-based carbon fiber obtained by carbonizing pitch fiber obtained from coal tar or heavy petroleum components as raw materials.

[0028] The shape of the carbon fibers 11 is not particularly limited and may be, for example, continuous fibers, short fibers, or a combination thereof. It may also be in the form of a woven fabric, a mat, etc. In the present invention, from the viewpoint of improving strength, it is preferable that the shape of the carbon fibers 11 constituting the CFRP base material is continuous fibers. In the case of continuous fibers, carbon fiber reinforced resins include unidirectional materials (UD materials) in which carbon fibers (continuous fibers) are arranged in one direction, or cloth materials in which fibers extend in multiple directions by plain weave, twill weave, etc. From the viewpoint of ensuring the strength of the composite material 1 of the present invention, it is preferable that the base material 10 includes a unidirectional material (UD material). Alternatively, it may consist only of a unidirectional material (UD material).

[0029] The length of the carbon fibers is arbitrary as long as it does not impair the objectives of the present invention. In the case of short fibers, the length is not particularly limited, but for example, it is generally around 3 mm to 24 mm, which offers excellent moldability and applicability to complex-shaped parts. On the other hand, continuous fibers are often used in their long lengths depending on the shape and dimensions of the molded product, exhibiting excellent tensile strength and rigidity.

[0030] The diameter of the carbon fiber can be arbitrary as long as it does not impair the purpose of the present invention, but for example, the diameter of a single fiber is about 5 to 10 μm. In the examples described later, a substrate with carbon fiber diameters of about 7 μm is used.

[0031] Density of carbon fibers in substrate 10 (1 mm 2 Number of carbon fibers per unit (fibers / mm) 2 )) is optional as long as it does not impair the purpose of the present invention, for example, 6000 strands / mm 2 In total, 12,000 strands / mm 2 Above 15,000 strands / mm 2 In total, 24,000 strands / mm 2 That concludes the explanation. Note that in the embodiments described later, the density of carbon fibers is approximately 16,000 fibers / mm². 2 It uses the following base material.

[0032] The CFRP layer constituting the base material 10 may be a single layer or multiple layers, but from the viewpoint of improving strength, it is preferable to have a laminated structure.

[0033] When the base material 10 according to the present invention is a laminate, it is preferable to include unidirectional carbon fiber material (UD material) from the viewpoint of ensuring the strength of the composite material 1 of the present invention. That is, the base material (laminated body) according to the present invention may be formed by laminating unidirectional carbon fiber material, or it may be formed by laminating a combination of unidirectional material and material other than unidirectional material (for example, cross material, short fiber-retaining CFRP, etc.). Here, "unidirectional material (of carbon fibers)" (UD material) refers to a material in which carbon fibers (continuous fibers) are arranged in a single direction.

[0034] From the viewpoint of easily forming the cutting grooves 13 uniformly, the base material 10 is preferably a laminate in which at least the outermost surface is a unidirectional material in which carbon fibers 11 (continuous fibers) are arranged in one direction, and more preferably a laminate consisting only of unidirectional material.

[0035] The resin 12 is the base material (matrix resin) of the substrate 10, and the carbon fibers 11 are embedded in it to form a carbon fiber reinforced polymer (CFRP).

[0036] The resin 12 can be any of the various resins commonly used as matrix resins for CFRP, and can be either a thermosetting resin or a thermoplastic resin. Examples of resin 12 include thermosetting resins such as epoxy resins, unsaturated polyester resins, vinyl ester resins, urethane resins, phenolic resins, alkyd resins, xylene resins, and melamine resins; and thermoplastic resins such as polyethylene, polypropylene, polyvinyl chloride, polystyrene, ABS resin, fluororesin, polycarbonate, polyethylene terephthalate, polybutylene terephthalate, polysulfone, polyethersulfone, polyetheretherketone, polyphenylene oxide, and polyphenylene sulfide.

[0037] Furthermore, the CFRP according to the present invention comprises carbon fibers and a matrix resin, and may further include any known additives as needed.

[0038] The base material 10 in the composite material 1 of the present invention has cutting grooves 13 on its surface. As shown in Figure 2(a), the cutting grooves 13 are grooves (recesses) formed on the surface of the base material 10, and are formed to a depth in which the carbon fibers 11 embedded in the CFRP base material 10 are actually cut. The cross-sectional shape of the cutting groove 13 is arbitrary as long as it achieves the effects of the present invention. The method for forming the cutting groove 13 will be described later in <2. Method for manufacturing carbon fiber reinforced resin composite material>. A groove 19 that does not reach the depth to cut the carbon fibers may also be included, but the groove 19 is not included in the cutting groove 13.

[0039] The cutting groove 13 is formed as a recess on the substrate surface where the carbon fibers are cut, and the cut carbon fibers are exposed inside, forming a fine uneven surface. As described below, a first metal layer 20 is formed on the surface of the base material 10, and as the first metal penetrates into the cut groove 13, the metal fills and adheres to the gaps (fine irregularities) between the cut carbon fibers, thereby strengthening the anchoring effect. In other words, the cut groove 13 is formed to create an anchoring effect by the first metal layer 20, improving the adhesion between the base material 10 and the first metal layer 20.

[0040] The width, depth, and density of the cutting grooves 13 are designed to provide an anchoring effect between the base material 10 and the first metal layer 20, thereby ensuring adhesion.

[0041] The cutting groove 13 is formed with a width that allows the first metal to penetrate into the interior of the cutting groove 13. The width of the cutting groove 13 (the length in the direction perpendicular to the extension direction of the cutting groove on the substrate surface) can be appropriately set within a range that fully demonstrates the effects of the present invention. Specifically, the lower limit can be 10 μm or more, 30 μm or more, 50 μm or more, 80 μm or more, or 100 μm or more, and the upper limit can be 500 μm or less, 400 μm or less, 350 μm or less, 300 μm or less, 200 μm or less, or 150 μm or less. Any combination of these lower and upper limits can be set. For example, the width of the cutting groove 13 can be 100 to 400 μm. The width of the cutting groove 13 is determined by first calculating the average height of the target area containing at least one cutting groove 13 using a laser microscope. Next, the distance between two positions corresponding to the average height in the cutting groove 13 is measured. This measurement is performed at any three locations, and the width can be determined as the average value of the three measurement results.

[0042] The cutting groove 13 is formed to a depth in which the carbon fibers are cut. The depth of the cutting groove 13 (the straight-line distance perpendicular to the substrate surface from the substrate surface where the cutting groove is formed to the bottom of the cutting groove) can be appropriately set within a range that fully demonstrates the effects of the present invention. Specifically, the lower limit can be 10 μm or more, 30 μm or more, 50 μm or more, 80 μm or more, 100 μm or more, or 150 μm or more, and the upper limit can be 500 μm or less, 450 μm or less, 400 μm or less, 300 μm or less, 200 μm or less, 150 μm or less, or 100 μm or less. Any combination of these lower and upper limits can be set arbitrarily. For example, the depth of the cutting groove 13 can be 100 to 500 μm. The depth of the cutting groove 13 can be determined using a laser microscope, by taking measurements at any three locations and taking the average length from the surface of the CFRP to the deepest point of the cutting groove 13 (the length in the direction normal to the surface of the CFRP).

[0043] The cutting groove 13 is formed with sufficient density to provide an anchoring effect. While a higher density of cut grooves improves the anchoring effect, excessively high density can cause the cut carbon fibers to become shorter, making the substrate surface more prone to peeling (reducing peel resistance). The density of the cutting grooves 13 on the substrate surface (the number of cutting grooves per unit length (in the case of a cylindrical substrate, the unit length in the direction of the central axis of the cylindrical shape) on the substrate surface where the cutting grooves are formed) is, for example, 1 groove / cm or more and 30 grooves / cm or less, preferably 2 grooves / cm or more and 20 grooves / cm or less, and more preferably 4 grooves / cm or more and 12 grooves / cm or less.

[0044] The base material 10 according to the present invention can take any shape as long as it does not impair the purpose of the present invention. For example, it can be plate-shaped, sheet-shaped, square pipe-shaped, L-shaped, T-shaped, C-shaped, H-shaped in cross-section, cylindrical, conical, rectangular parallelepiped, or any other three-dimensional shape. The shape of the base material 10 can be selected according to the application of the composite material 1 of the present invention, for example, a cylindrical shape (CFRP roll) can be given.

[0045] The dimensions of the base material 10 according to the present invention are arbitrary. For example, if it is a flat shape (CFRP plate), the length, width, and thickness of the base material can be set as appropriate. Also, if it is a cylindrical shape (CFRP roll), the length in the direction of the central axis, the diameter, and the thickness can be set as appropriate.

[0046] The thickness of the base material 10 is appropriately selected according to the intended use of the composite material 1 of the present invention. If the thickness is excessively large, it will lead to an increase in weight, while if it is excessively small, it may result in insufficient strength. The thickness of the base material 10 is, for example, 1 mm or more and 50 mm or less, preferably 1.5 mm or more and 40 mm or less, and more preferably 2 mm or more and 30 mm or less.

[0047] [1-2. First metal layer] The composite material of the present invention has a first metal layer consisting of a first metal laminated on the surface of a substrate. The first metal layer functions as an intermediate layer (underlayment layer) provided between the substrate and the second metal layer, exhibiting mechanical interlocking (anchor effect). Furthermore, when the second metal layer is formed by plating, it also functions as a conductive layer during plating.

[0048] As shown in Figure 1, the composite material 1 of the present invention has cutting grooves 13 on the surface of the base material 10, and the first metal constituting the first metal layer 20 is penetrated into the cutting grooves 13. By adopting this configuration, an anchoring effect is generated between the base material 10 and the first metal layer 20, improving the adhesion between the two.

[0049] The thickness of the first metal layer 20 according to the present invention is arbitrary as long as it does not impair the objective of the present invention. The thickness of the first metal layer 20 is, for example, 50 μm or more and 2000 μm or less, 100 μm or more and 1000 μm or less, 150 μm or more and 800 μm or less, or 200 μm or more and 650 μm or less. If the first metal layer 20 is too thick, the amount of material used and the weight will increase, and if it is too thin, the anchoring effect and the conductivity of the plating in process (3) will be insufficient.

[0050] The thickness of the first metal layer is determined by measuring the substrate thickness before the formation of the first metal layer (substrate thickness only) and the thickness after formation (substrate + first metal layer thickness) at four or more points using a micrometer, and calculating the difference in the average values. The thicknesses of the second and third metal layers can be calculated using a similar method.

[0051] The first metal (thermal spray material) according to the present invention is arbitrary as long as it can ensure conductivity when the second metal layer 30 is laminated on its surface, and the first metal constituting the first metal layer 20 penetrates into the cutting groove 13.

[0052] A metal or alloy (which may contain unavoidable impurities) is used as the first metal (thermal spray material). Preferably, the first metal is a metal selected from the group consisting of Cu, Al, Zn, Ni, or Fe, or an alloy containing these. From the viewpoint of ease of lamination of the first metal layer 20 by thermal spraying, ensuring conductivity and interlayer adhesion when laminating the second metal layer 30 on its surface, the first metal is preferably Cu or a Cu alloy. For the Cu alloy, a Cu-Sn alloy containing Sn is preferred. The Sn content can be appropriately selected according to the balance of conductivity, welding efficiency, and film hardness, for example, 0.5 to 10% by mass.

[0053] As described above, the first metal constituting the first metal layer 20 according to the present invention can exert an anchoring effect by penetrating into the interior of the cutting groove 13, thereby improving adhesion with the base material 10. Furthermore, the first metal constituting the first metal layer 20 can fill and fix the gaps between the carbon fibers 11 and the matrix resin 12 exposed inside the cutting groove 13, thereby improving the strength and peel resistance of the base material 10 (and composite material 1).

[0054] Figure 3 shows the state of penetration of the first metal layer 20 into the cut groove 13. The first metal may fill the inside of the cut groove 13 substantially without voids (Figure 3(a)), or it may leave some voids 14 (Figure 3(b)). However, from the viewpoint of improving the anchoring effect and mechanical strength, void-free filling (substantially filling) is preferred. Substantially void-free means a state in which the ratio of void volume to the volume of the cut groove is 10 volume% or less (preferably 5 volume% or less).

[0055] [1-3.Second metal layer] The composite material of the present invention has a second metal layer made of a second metal laminated on the surface of a first metal layer. The second metal layer is provided (laminated) on the surface of the first metal layer and functions as a hard layer that increases the hardness (strength) of the composite material.

[0056] As shown in Figure 1, the composite material 1 of the present invention has a second metal layer 30 laminated on the surface of a first metal layer 20. The lamination of the second metal layer 30 improves the surface hardness of the composite material 1 and improves properties such as wear resistance.

[0057] The thickness of the second metal layer 30 according to the present invention is arbitrary as long as it does not impair the objective of the present invention. The thickness of the second metal layer is, for example, 10 μm or more and 300 μm or less, 20 μm or more and 200 μm or less, or 30 μm or more and 100 μm or less. If the second metal layer 30 is too thick, it may result in increased costs due to the increased amount of the second metal and an increase in the weight of the composite material 1. If the second metal layer 30 is too thin, the surface strength (hardness) may be insufficient.

[0058] The second metal according to the present invention is arbitrary as long as it does not impair the purpose of the present invention. The second metal can be a metallic material (metal or alloy (which may contain unavoidable impurities)). Preferred secondary metals include metals selected from the group consisting of Ni, Cr, Al, or Zn, or alloys containing these metals. From the viewpoint of strength and productivity, the second metal is preferably Ni, Cr, or a Ni alloy, or a Cr alloy.

[0059] Furthermore, the second metal used in the second metal layer may be the same metal as the first metal used in the first metal layer.

[0060] The second metal layer 30 according to the present invention may be a single layer or multiple layers. In the case of multiple layers, it may be a multilayer structure made of the same material or a multilayer structure made of a combination of different materials.

[0061] The second metal layer 30 can be laminated by plating in step (3) described later. The selection of the plating method is determined appropriately according to the shape, required characteristics, and productivity.

[0062] [1-4.Third layer] The composite material of the present invention may further have a third layer made of a material harder than the second metal layer on the surface of the second metal layer. The third layer contributes to imparting surface hardness and improving surface smoothness.

[0063] The thickness of the third layer is arbitrary as long as it does not impair the purpose of the present invention, and is, for example, 0.5 μm or more and 10 μm or more and 1 μm or more and 5 μm or less. The material used for the third layer, which is harder than the second metal layer, is not limited, but examples include metal nitrides or metal oxides. Examples of metal nitrides include nitrides of metals selected from Ti, Cr, Al, Zr and combinations thereof, and preferably TiN, CrN, or CrAlN.

[0064] The composite material of the present invention can be manufactured using any manufacturing method as long as the objective of the present invention is not impaired, but preferably it can be manufactured using the following method for manufacturing carbon fiber reinforced resin composite materials (hereinafter sometimes referred to as the manufacturing method of the present invention).

[0065] <1-5.Application examples> The composite material of the present invention is suitable for the following applications, but is not limited to these. (a) Guide rolls / nip rolls in manufacturing lines for high-performance films such as LCDs (b) Long rolls used in the papermaking process (c) Conveyor rolls for a secondary battery separator manufacturing line

[0066] <2. Method for manufacturing carbon fiber reinforced resin composite materials> The present invention relates to a method for manufacturing a composite material, comprising the steps of: (1) forming the cutting grooves on the surface of a substrate; (2) thermal spraying the first metal onto the substrate having the carbon fiber cutting grooves so as to penetrate into the carbon fiber cutting grooves to laminate the first metal layer; and (3) plating the surface of the first metal layer with the second metal to laminate the second metal layer.

[0067] The details of the manufacturing method for the composite material of the present invention will be described below with reference to the drawings. Figure 4 shows a schematic diagram of the substrate according to the present invention (before process (1)) and an enlarged view of a part thereof; Figure 5 shows a schematic diagram of the substrate according to the present invention (after process (1)) and an enlarged view of a part thereof; Figure 6 shows a schematic diagram of one embodiment of the substrate according to the present invention (after process (1)) (cylindrical substrate); and Figure 7 shows a schematic diagram of the substrate according to the present invention (after process (2)) and an enlarged view of a part thereof. In addition, in Figures 4 to 7, the size of the carbon fibers and carbon fiber cutting grooves, the thickness of each metal layer, etc., may be schematically emphasized to facilitate understanding of the structure of the composite material of the present invention.

[0068] [2-1. Process (1)] Step (1) is a step of forming the carbon fiber cutting grooves on the surface of the substrate. By forming the cutting grooves on the surface of the substrate, the first metal constituting the first metal layer formed in step (2) penetrates into the cutting grooves, improving the adhesion (anchor effect) between the substrate and the first metal layer.

[0069] The method for forming the cutting groove is not limited; for example, a mechanical cutting process can be used to form the groove by physically cutting the surface of the substrate.

[0070] In mechanical cutting, a cutting tool is moved relative to the substrate surface while in contact with it, cutting the carbon fibers within the substrate to form grooves. Specifically, in mechanical cutting, the sharp end face of the cutting tool is pressed against the surface of the substrate, and the cutting tool is moved to cut the carbon fibers embedded in the substrate, thereby forming cutting grooves. The relative movement may be performed on the cutting tool side, the substrate side, or both.

[0071] The cutting tool used in this invention can be any tool as long as it can cut the carbon fibers of the CFRP substrate. The shape of the cutting tool may be, for example, straight, arc-shaped, or V-shaped. The material of the cutting tool may be, for example, metal or ceramic.

[0072] Figure 4 shows the substrate 10 before process (1) (before the formation of cutting grooves by mechanical cutting). The surface of the substrate 10 before process (1) is covered with the resin 12 (matrix resin) that constitutes the CFRP, and no irregularities are formed, making it substantially smooth.

[0073] Next, as shown in Figure 5, the mechanical cutting process in step (1) cuts the carbon fibers 11 embedded in the substrate 10, forming a cutting groove 13 on the surface of the substrate 10. This process allows the first metal, which constitutes the first metal layer 20 to be laminated in step (2) described later, to penetrate into the cutting groove 13, improving the anchoring effect (adhesion) between the first metal layer 20 and the substrate 10. As shown in Figure 2(a), the cutting groove 13 is a groove formed to the depth to which the carbon fibers 11 are actually cut, and its cross-sectional shape is arbitrary as long as it does not impair the effects of the present invention. On the other hand, the groove 19 shown in Figure 2(b), which does not reach the depth to which the carbon fibers are cut, is not included in the cutting groove 13.

[0074] The base material shape of the present invention is arbitrary, but if the base material is cylindrical (CFRP roll), the mechanical cutting process of step (1) can be performed on the circumferential surface to cut the carbon fibers on the circumferential surface and form a cutting groove 13. At this time, the processing blade is moved relative to the circumferential surface while in contact with it, and the contact position is changed sequentially.

[0075] The process of cutting the carbon fibers of a cylindrical base material (CFRP roll) may be carried out while rotating the base material around its central axis. Alternatively, the process may be carried out while moving the cutting tool in the direction of the central axis.

[0076] By simultaneously rotating the substrate and moving the cutting tool in the axial direction, a helical cutting groove 13 can be formed on the circumferential surface, as shown in Figure 6. That is, the cutting grooves 13 are arranged at approximately equal intervals in the direction of the central axis. This process simplifies the process and improves productivity. Note that rotation and movement may be performed individually, simultaneously, or alternately. Specific examples of the cutting tools used will be described later in the examples.

[0077] From the viewpoint of easily forming uniform cutting grooves 13, the cylindrical base material 10 is preferably a laminate in which at least the outermost layer (circumferential surface) is made of unidirectional carbon fiber material. Furthermore, when using unidirectional material, the fiber direction can be arbitrary, but from the viewpoint of productivity, it is preferable that it is parallel to the central axis direction of the cylinder.

[0078] Furthermore, any surface roughening treatment may be performed prior to step (1). As an arbitrary surface roughening treatment, for example, blast treatment (a process in which particles having a predetermined particle size distribution are blasted onto an object at high pressure to create irregularities on the surface of the object) may be performed on the surface of the substrate. Blasting treatment removes a portion of the resin on the surface of the substrate, exposing the carbon fibers and facilitating the subsequent cutting process.

[0079] As shown in Figure 5, in step (1) of the present invention, cutting grooves are formed on the surface of the substrate 10. However, if the surface roughness is too high, many carbon fibers are cut, the substrate (and composite material) is prone to peeling, and its strength decreases. Conversely, if the surface roughness is too low, the surface irregularities of the substrate are insufficient, resulting in inadequate adhesion with the first metal layer on the substrate surface. Therefore, the arithmetic mean roughness (Ra) of the substrate surface formed in step (1) is preferably 3 μm or more and 30 μm or less, and more preferably 4 μm or more and 20 μm or less. The arithmetic mean roughness (Ra) is measured in accordance with the measurement method specified in JIS B0601:2013. At the measurement point, the arithmetic mean roughness Ra is measured over the evaluation length extending in the direction normal to the surface of the substrate.

[0080] [2-2. Process (2)] Step (2) is a step of laminating a first metal layer by thermal spraying the first metal onto the substrate in which the cutting groove has been formed, so as to penetrate into the interior of the cutting groove. Step (2) creates an anchoring effect between the substrate and the first metal layer (thermal spray layer), improving adhesion and ensuring conductivity during the subsequent plating step (3).

[0081] As shown in Figure 7, the first metal layer 20 is laminated onto the surface of the substrate 10 by thermal spraying in step (2).

[0082] The thermal spraying performed in step (2) is optional as long as it does not impair the objective of the present invention. Thermal spraying is generally broadly classified into two types: gas-type and electric-type, and electric-type thermal spraying is preferred from the viewpoint of ease of control.

[0083] Examples of electro-spraying include arc spraying, in which the spray material is heated by an arc, and plasma spraying, which uses a plasma jet generated by an arc as an energy source. From the viewpoint of being able to spray a large amount of material, shortening construction time, and improving productivity, and also from the viewpoint of being able to form a sprayed layer at a relatively low temperature and protecting the CFRP substrate, arc spraying is more preferred as the thermal spraying method according to the present invention.

[0084] Arc spraying is a method in which an arc is generated between the tips of a spray wire that is continuously fed through two nozzles. The heat from this arc melts the spray material, which is then dropletized by an air jet ejected from an intermediate nozzle. These droplets are then sprayed onto the substrate surface to form a coating.

[0085] Furthermore, the thermal spraying conditions according to the present invention are arbitrary as long as they do not impair the objective of the present invention. When using arc thermal spraying, the arc thermal spraying conditions (current, voltage, gas pressure, nozzle shape, etc.) can be appropriately set within the range in which the desired coating can be obtained.

[0086] When arc spraying is used in step (2), the conditions should be such that the first metal penetrates sufficiently into the cut groove and forms the desired first metal layer. For example, the arc current should be 80A to 200A, the arc voltage 30V to 50V, and the gas pressure 0.2MPa to 1MPa.

[0087] After forming the first metal layer 20 in step (2), the first metal layer 20 may be ground or polished (cylindrical grinding or turning in the case of a cylindrical shape) as needed. This allows for thickness adjustment and surface smoothing, which makes the thickness distribution of the second metal layer 30 formed in step (3) uniform and contributes to improving the strength of the composite material 1.

[0088] Furthermore, if necessary, the first metal layer 20 may be subjected to blast treatment after grinding or polishing. This further improves the adhesion between the first metal layer 20 and the second metal layer 30.

[0089] [2-3. Process (3)] Step (3) is a process of plating the second metal onto the surface of the first metal layer to laminate the second metal layer. By laminating the second metal layer, the hardness (wear resistance) of the composite material can be increased.

[0090] The plating process in step (3) causes the second metal layer 30 to be laminated onto the surface of the first metal layer 20 (see Figure 1).

[0091] The plating performed in step (3) is optional as long as it does not impair the objective of the present invention. Plating is broadly classified into three types: dry, wet, and molten. However, from the viewpoint of quality and productivity, wet plating is preferred as the plating method according to the present invention. Examples of wet plating include electrolytic (electrostatic) plating and electroless plating. From the viewpoint of ease of film formation, cost, and productivity, electrolytic plating is more preferred as the plating method according to the present invention.

[0092] The plating conditions according to the present invention are not limited. In the case of electroplating, the current, electrolyte composition, temperature, stirring, jig, and apparatus configuration are set appropriately within the range in which the desired layer can be obtained.

[0093] After lamination of the second metal layer 30 in step (3), the second metal layer 30 may be ground or polished (cylindrical grinding or turning if the shape of the base material is cylindrical). The thickness of the second metal layer 30 can be adjusted by grinding or polishing it. Furthermore, the surface of the second metal layer 30 can be smoothed to achieve a mirror finish or a predetermined surface roughness.

[0094] Furthermore, as long as the objective of the present invention is not impaired, a third layer may be formed (laminated) on the surface of the second metal layer 30 after laminating the second metal layer 30 in step (3). Typically, a hard layer can be used as the third layer, which can improve the strength and smoothness of the composite material 1. The method for forming the third layer is arbitrary; for example, the surface layer may be formed by vapor deposition. The conditions for forming the third layer (temperature, pressure, material, etc.) are also arbitrary. Furthermore, when forming the third layer, the surface of the second metal layer 30 may be ground or polished (cylindrical grinding or turning if the shape of the base material is cylindrical) before forming the third layer.

[0095] When forming a third layer by vapor deposition after lamination of the second metal layer 30 in step (3), the vapor deposition conditions are set to conditions that can form the desired surface layer (vapor-deposited layer). For example, the vapor deposition conditions are a temperature of 100°C to 200°C and an atmospheric pressure of 1 × 10⁻⁶. -3 The pressure is between Pa and 10 Pa. Examples of materials used for vapor deposition include metallic materials, carbide materials, nitride materials (TiN, CrN, CrAlN, etc.), oxide materials, and organic materials.

[0096] While embodiments of the present invention have been described above with reference to the drawings, the embodiments disclosed herein are illustrative and not restrictive in all respects. In particular, matters not explicitly disclosed in the embodiments disclosed herein, such as operating conditions, various parameters, dimensions, weights, and volumes of components, do not deviate from what is normally practiced by those skilled in the art, and the values ​​adopted are those that can be easily anticipated by those skilled in the art. [Examples]

[0097] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0098] <1. Experimental Example 1 (CFRP Plate)> Process (1) A CFRP (carbon fiber reinforced polymer) plate (UD material, 50mm in length, 50mm in width, and 5mm in thickness) was used as the base material. First, the surface of the CFRP plate was blast-treated (alumina #24). After blasting, a cutting tool was brought into contact with the surface of the CFRP plate, and the cutting tool was moved to change the position of contact with the cutting tool on the surface of the CFRP plate, thereby cutting the carbon fibers of the CFRP plate and forming carbon fiber cutting grooves (cutting grooves). The formed cutting grooves were nearly parallel, with a distance between them of 0.9 to 2.1 mm, and a density (number of cutting grooves per unit length on the substrate surface) of 4 to 12 grooves / cm.

[0099] Process (2) After forming the cutting grooves, arc spraying was performed on the surface of the CFRP plate (the substrate on which the cutting grooves were formed). The arc spraying was carried out under the following conditions: distance from the spray gun of 150 mm, Cu brazing material (JIS Z 3341:2007 YCu, manufactured by Nippon Welding Co., Ltd., brand name WEL MIG Cu) material supply rate of 60 g / min, and pitch of 40 mm / second. High-speed air was applied perpendicular to the surface of the CFRP plate to allow the spray material (first metal) to penetrate into the cutting grooves, forming a 500 μm thick Cu sprayed layer.

[0100] The surface of the CFRP plate during the intermediate stage of thermal spraying in process (2) and after thermal spraying was completed was observed using an optical microscope (Evident Co., Ltd., model number OLS5100-EAT). Figure 8 shows a cross-sectional image (perspective photograph) of a CFRP plate in the mid-stage of thermal spraying. As shown in Figure 8, a Cu thermal spray layer is formed on the surface of the CFRP plate along the shape of the cut groove, and it was confirmed that Cu has penetrated into the interior of the cut groove. Furthermore, as shown in Figure 9, in the CFRP plate after further thermal spraying, it was confirmed that the Cu thermal spray layer has penetrated into the interior of the cut groove on the surface of the CFRP plate, and the cut groove is completely filled with Cu.

[0101] Process (3) The composite material of Experimental Example 1 was obtained by blasting the surface of a CFRP plate with a Cu thermal spray layer, and then plating it in a Cr solution to form a Cr plating layer.

[0102] (Evaluation of adhesion strength) The adhesion strength (MPa) of the Cu thermal spray layer on a CFRP plate after Cu thermal spraying was evaluated using the peel test described below.

[0103] (Peel test) For the peel test, CFRP plates were processed under groove conditions A and B below after blasting (alumina #24, irradiation distance 150 mm, air pressure 0.6 MPa). These plates were then processed into 20 mm diameter discs, which were used as samples A and B. The width, depth, and pitch of the grooves in samples A and B were determined by observing the cross-section of each sample with a laser microscope. Exposed carbon fibers were also observed in the grooves of samples A and B before thermal spraying. For comparison, a similar peel test was also performed on sample C, which was blasted under the same conditions but without groove processing.

[0104] Sample A: Width 150-400 μm, depth 250-400 μm, pitch 0.9-1.7 mm Sample B: Width 50-150 μm, depth 50-250 μm, pitch 0.9-1.7 mm Sample C: No groove machining:

[0105] Samples A to C were subjected to a Cu thermal spray coating under the conditions of Experimental Example 1. Epoxy adhesive (Konishi Corporation, model #16123) was then applied to the surface of the thermal spray coating and the back surface of the CFRP plate, and the samples were bonded to a jig of the same diameter. After the adhesive cured, excess adhesive was removed using a rotary tool to match the jig diameter. The samples bonded to the jig were then attached to a tensile and compression testing machine (Minebea Atsumi Corporation, model TG-10kN) via a universal joint, and a tensile load was applied between the thermal spray coating and the CFRP substrate at a test speed of 1 mm / min. The tensile load at which fracture occurred between the thermal spray coating and the CFRP substrate was divided by the cross-sectional area of ​​the jig to determine the adhesion strength (MPa). The results are shown in Table 1.

[0106] [Table 1]

[0107] No defects were observed in the appearance of any of the samples A through C, and it was determined that the copper had been uniformly sprayed. In the peel test, samples A and B showed significantly higher adhesion strength compared to sample C, which did not have cut grooves, indicating that the cut grooves improved adhesion between the Cu thermal spray layer and the substrate. Furthermore, sample B, with smaller cut groove dimensions, showed higher adhesion strength than sample A, which had larger cut groove dimensions. Therefore, it can be said that it is advantageous to make the cut grooves narrow and of an appropriate depth within a range where the thermal spray metal can reliably penetrate, rather than making them excessively large, and to increase the number of grooves per unit length (number of anchors) and the effective side area. The test system was identical in substrate, thermal spray material, film thickness, jig, and load conditions, and the adhesion strength was calculated by normalizing the breaking load with the jig cross-sectional area, so the obtained differences mainly correspond to the difference in anchor effect due to the groove shape. The above confirms that the formation of cutting grooves allows the Cu thermal spray layer to mechanically penetrate into the grooves and between the cutting fibers, resulting in mechanical interlocking (anchoring effect) and improved adhesion to the substrate.

[0108] <2. Experimental Example 2 (CFRP Roll)> The carbon fiber reinforced resin composite material of Experimental Example 2 (hereinafter referred to as the "composite material of Experimental Example 2") was produced as follows.

[0109] As a base material made of carbon fiber reinforced resin, a CFRP roll (manufactured by Toray Industries, Inc., length 480 mm, diameter 59 mm; CF diameter 7 μm, CF density 16,000 pieces / mm 2 ) was used. Fig. 10 shows the overall photograph (top) and enlarged photograph (bottom) of the CFRP roll (untreated).

[0110] The surface of the CFRP roll was subjected to blasting treatment (aluminum oxide #24) after cylindrical grinding. After the blasting treatment, while rotating the CFRP roll around the central axis (rotation speed 160 rpm), a cutting tool for processing was brought into contact with the circumferential surface of the CFRP roll, and the cutting tool was moved parallel to the central axis of the CFRP roll to form cutting grooves on the surface of the CFRP roll so that the density became 4 to 12 pieces / cm (Step (1)). Fig. 11 shows the overall photograph (top) and enlarged photograph (bottom) of the CFRP roll (after cutting groove formation). It was confirmed that the cutting grooves were formed in a spiral shape on the circumferential surface of the CFRP roll (cylindrical base material). Also, the cutting grooves were formed at substantially equal intervals in the direction of the central axis of the CFRP roll (cylindrical base material). The spiral cutting grooves formed on the CFRP roll had a cutting groove depth of about 0.2 to 0.4 mm, a cutting groove width of about 0.2 to 0.3 mm, and a pitch of about 1.5 mm.

[0111] After forming the cutting grooves, arc spraying was performed on the circumferential surface of the CFRP roll (the base material on which the cutting grooves were formed). The arc spraying was performed under the conditions of a distance of 150 mm from the spraying gun, a material of pure copper (manufactured by Nippon Welding Co., Ltd., brand WEL MIG Cu), a material supply rate of 60 g / min, a CFRP roll rotation speed of 450 rpm, and a pitch of 40 mm / second, with high-speed air being applied from a direction perpendicular to the central axis of the CFRP roll so that the spraying material (the first metal) penetrated into the inside of the cutting grooves, and a Cu sprayed layer with a film thickness of 500 μm was formed (Step (2)). Fig. 12 shows the overall photograph (top) and enlarged photograph (bottom) of the CFRP roll (after Cu sprayed layer formation). The CFRP rolls after the Cu thermal spray layer was formed were reddish-brown overall due to the Cu content, and as shown in the lower part of Figure 12, it was confirmed that the inside of the cut grooves was filled with Cu.

[0112] After thermal spraying, the surface of the CFRP roll (Cu thermal spray layer) was again subjected to cylindrical grinding followed by blast treatment (alumina #24). Subsequently, a current density of 70-80 A / cm² was applied to a Cr solution (Cr anhydride: 250 g / L, sulfuric acid: 2.5 g / L, 50-60°C). 2 After energizing for 30 minutes, the current density was 30-35 A / cm². 2 The material was energized for 14-16 hours to form a Cr plating layer with a thickness of 150-200 μm (step (3)). After plating, cylindrical grinding was performed again on the surface (Cr plating layer) of the CFRP roll to a thickness of 50 μm. Subsequently, CrN deposition was performed under conditions of 100-150°C and 2 Pa to a thickness of 3 μm, and the composite material of Experimental Example 2 was fabricated.

[0113] Figure 13 shows an external photograph of the composite material from Experimental Example 2, and Figure 14 shows a magnified photograph of the surface lamination. As shown in Figure 14, it was confirmed that a Cu thermal spray layer (first metal layer 20) was laminated on a CFRP roll (substrate 10 made of carbon fiber reinforced resin), a Cr plating layer (second metal layer 30) was laminated on the Cu thermal spray layer, and a CrN vapor deposition layer (third layer) was laminated on the Cr plating layer.

[0114] Furthermore, to evaluate the adhesion of the formed laminated film, a Rockwell indentation test (ISO 26443, VDI 3198) was performed on the composite layer containing the CrN vapor-deposited layer. This test involves using a diamond Rockwell C indenter to apply an indentation with a standard load of 150 kgf, observing the delamination state around the indentation at 100x magnification, and determining the grade according to the standard (VDI: HF1~HF6, ISO: Class 0~3). As a result of the test, no extensive delamination due to interfacial delamination was observed around the indentation, and the grade was within the acceptable range. Therefore, it was determined that there was no delamination and the interfacial adhesion was good.

[0115] <Reference Data> (Surface observation and roughness measurement of CFRP rolls) Surface observation, wire roughness, and surface roughness measurements were performed on the CFRP roll used in Experimental Example 2 before treatment, after blast treatment, and after carbon fiber cutting groove formation (corresponding to process (1) in each case).

[0116] (A. Surface observation) (Unprocessed CFRP roll) Figure 15 shows a laser brightness image (magnification 452x) of the surface of an untreated CFRP roll observed with a laser microscope (Evident, model OLS5100-EAT). The surface of the untreated CFRP roll showed relatively little exposure of carbon fibers, and no carbon fiber breakage was observed.

[0117] (CFRP roll after blast treatment) Figure 16 shows a laser brightness image of the CFRP roll surface after blasting. Exposure of carbon fibers was observed on the surface of the CFRP roll after blasting, but no cutting of the carbon fibers was observed.

[0118] (CFRP roll after cutting groove formation) Figure 17 shows a laser brightness image of the CFRP roll surface after cutting groove formation. In Example 2, the CFRP roll after cutting groove formation showed evidence of cutting of exposed carbon fibers.

[0119] (B. Line roughness and surface roughness) The surface roughness (circumferential surface of the CFRP roll) of untreated, blast-treated, and carbon fiber cutting groove-formed CFRP rolls was measured using a laser microscope (Evident, model OLS5100-EAT). The results are shown in Table 2.

[0120] [Table 2]

[0121] As shown in Table 2, it was confirmed that the line roughness and surface roughness increased with each step of process (1). [Industrial applicability]

[0122] According to the present invention, a carbon fiber reinforced resin composite material is provided in which the adhesion of the metal layer to the carbon fiber reinforced resin substrate is improved, and is suitable for use as guide rolls / nip rolls in high-performance film manufacturing lines such as liquid crystals, long rolls in papermaking processes, and conveyor rolls in secondary battery separator manufacturing lines. [Explanation of symbols]

[0123] 1. Carbon fiber reinforced polymer (CFRP) composite material 10 Base material (CFRP base material) 11 Carbon Fiber 12. Resin (matrix resin) 13. Cutting groove (carbon fiber cutting groove) 14 void 19 Groove 20 First metal layer (first metal) 30 Second metal layer (second metal)

Claims

1. It comprises a base material made of carbon fiber reinforced resin, a first metal layer made of a first metal laminated on the surface of the base material, and a second metal layer made of a second metal laminated on the surface of the first metal layer. The surface of the substrate has carbon fiber cutting grooves formed to a depth in which the carbon fibers in the substrate are cut. A carbon fiber reinforced resin composite material characterized in that the first metal constituting the first metal layer penetrates into the interior of the carbon fiber cutting groove.

2. The carbon fiber reinforced resin composite material according to claim 1, wherein the first metal penetrates to a position deeper than the exposed position of the cut carbon fibers in the carbon fiber cutting groove and is fixed to the inner surface of the carbon fiber cutting groove and the exposed carbon fibers.

3. The carbon fiber reinforced resin composite material according to claim 1, wherein the first metal fills the inside of the carbon fiber cutting grooves.

4. The carbon fiber reinforced resin composite material according to claim 1, wherein the shape of the base material is cylindrical.

5. The carbon fiber reinforced resin composite material according to claim 4, wherein the base material is cylindrical in shape, and carbon fiber cutting grooves formed on its outer surface are spirally arranged at substantially equal intervals with respect to the central axis direction.

6. The carbon fiber reinforced resin composite material according to claim 1, wherein the base material is a laminate formed by laminating unidirectional carbon fiber material.

7. The carbon fiber reinforced resin composite material according to claim 1, wherein the first metal is a metal selected from the group consisting of Cu, Al, Zn, Ni, or Fe, or an alloy containing these.

8. The carbon fiber reinforced resin composite material according to claim 1, wherein the second metal is a metal selected from the group consisting of Ni, Cr, Al, or Zn, or an alloy containing these.

9. The carbon fiber reinforced resin composite material according to claim 1, wherein the first metal is Cu or a Cu alloy, and the second metal is Ni or Cr.

10. The carbon fiber reinforced resin composite material according to claim 1, further comprising a third layer made of a material harder than the second metal layer on the surface of the second metal layer.

11. The carbon fiber reinforced resin composite material according to claim 10, wherein the third layer is TiN, CrN, or CrAlN.

12. A method for producing a carbon fiber reinforced resin composite material according to claim 1, The process of forming the carbon fiber cutting grooves on the surface of the substrate (1), Step (2) of laminating the first metal layer by thermal spraying the first metal onto the substrate in which the carbon fiber cutting grooves are formed so that it penetrates into the carbon fiber cutting grooves, Step (3) of plating the second metal onto the surface of the first metal layer to laminate the second metal layer, A manufacturing method having the following characteristics.

13. The manufacturing method according to claim 12, wherein in step (1), the surface of the substrate is blast-treated before forming the carbon fiber cutting grooves in the substrate.

14. The shape of the base material is cylindrical, The manufacturing method according to claim 12, wherein the carbon fiber cutting grooves are formed in a helical pattern on the circumferential surface of the cylindrical base material.

15. The carbon fiber cutting grooves are formed at substantially equal intervals in the direction of the central axis of the cylindrical base material. The manufacturing method according to claim 14, wherein the density of the carbon fiber cutting grooves in the direction of the central axis of the cylindrical base material is 1 fiber / cm or more and 30 fiber / cm or less.

16. The manufacturing method according to claim 15, wherein the arithmetic mean roughness (Ra) of the surface of the substrate on which the carbon fiber cutting grooves are formed in step (1) is 3 μm or more and 30 μm or less.

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