JP5284926B2 - Laminated body of metal and carbon fiber reinforced resin and method for producing the same - Google Patents

Description

  The present invention relates to a metal and a carbon fiber reinforced resin (hereinafter referred to as a metal and carbon fiber reinforced resin) suitable for a member that is lightweight and has high mechanical strength, high rigidity, and durability in fields such as automobiles, airplanes, electrical / electronic devices, medical devices, and architecture. , CFRP) and a manufacturing method thereof. More specifically, the present invention relates to a laminate of metal and CFRP that can firmly bond a metal body and a CFRP body having a triaxial woven structure to improve the rigidity and weight of the laminate, and a method for manufacturing the laminate.

Conventionally, by reducing the weight and increasing the strength of materials, it is possible to save fuel and reduce CO ₂ emissions for materials such as automobiles and aircraft, while higher materials for materials such as buildings. Therefore, various research and development have been conducted. Some of them are used in airplanes.

As such a technique, a technique related to a light metal / CFRP structural member in which a light metal and a carbon fiber reinforced resin (CFRP) are bonded with an adhesive is known (for example, see Patent Document 1).
On the other hand, a unidirectional prepreg sheet is often used as a carbon fiber reinforced resin, but this unidirectional prepreg sheet has strong anisotropy in mechanical and thermal characteristics. For this reason, several layers are laminated and formed so as to be pseudo-isotropic by combining the fiber directions to be different. In addition, a technique related to a triaxial woven fabric using pitch-based carbon fibers as a woven fabric and a manufacturing method thereof is also known (see, for example, Patent Document 2).

  Reinforcement / repair of structural material is made up of a single-layered sheet-like woven structure in which reinforcing yarns of different angles are alternately crossed to form a hole in the weave. A technique relating to a reinforcing material used in the above is also known (for example, see Patent Document 3).

Republished patent WO99 / 10168 A1 JP-A-9-170138 Japanese Patent Laid-Open No. 11-34199

However, such materials are used in, for example, some aircraft, but there is still room for improvement to be used as materials for various devices and equipment in other fields. It is requested to be done.
On the other hand, the present applicant has also earnestly researched and developed a bonded body in which CFRP and an adherend (CFRP or metal alloy) are firmly bonded and integrated. Further, Japanese Patent Application No. 2009-225057 (application date: September 29, 2009) proposes a technique related to a joined body of CFRP and an adherend and a manufacturing method thereof.

The present invention has been made to solve the above-described problems and achieves the following object.
It is an object of the present invention to firmly bond a metal and a carbon fiber reinforced resin having a triaxial woven structure to improve the rigidity, mechanical strength, durability, weight, and thickness of the laminate. Another object is to provide a laminate of carbon fiber reinforced resin and a method for producing the same.

The present invention employs the following means in order to achieve the above-described object.
In the laminate of the metal and the carbon fiber reinforced resin of the first aspect of the invention, the three carbon fiber bundles are woven so as to have a predetermined angle with each other. A carbon fiber reinforced resin body formed in a triaxial woven fabric so as to have a metal body laminated on the carbon fiber reinforced resin body, and a convex portion at a position corresponding to the opening portion It is composed of a formed metal body and an adhesive for integrally joining the carbon fiber reinforced resin body and the metal body, and the convex portion is positioned in the opening portion. And

  The laminate of the metal of the present invention 2 and the carbon fiber reinforced resin is the laminate of the present invention 1 in which the carbon fiber reinforced resin body and the metal body are integrally joined, and the carbon fiber reinforced resin body. And the other laminated body in which the metal body is integrally bonded to each other are bonded to each other at the flat surface of the metal body or the upper surface of the convex portion.

  In the laminate of the metal and the carbon fiber reinforced resin of the third aspect of the present invention, the three carbon fiber bundles are woven so as to have a predetermined angle with each other, and the opening portion having a predetermined shape is formed in a weave crossing each other alternately. A carbon fiber reinforced resin body formed on a triaxial woven fabric so as to have a metal plate, and a metal plate laminated on one of the carbon fiber reinforced resin bodies, protruding to a position corresponding to the opening portion A first metal body having a portion formed thereon, a metal plate laminated on the other of the carbon fiber reinforced resin bodies, and a second metal body having a hole formed at a position corresponding to the opening portion, It consists of the carbon fiber reinforced resin body, the first metal body, and an adhesive for joining the second metal body together.

  The laminated body of the metal of this invention 4 and carbon fiber reinforced resin in this invention 1-3 WHEREIN: The joining surface of the said carbon fiber reinforced resin body is a surface by which the roughening process was carried out.

  The laminate of the metal of the present invention 5 and the carbon fiber reinforced resin in the present invention 1 to 4, the joint surface of the metal body is subjected to etching, so that the mean valley interval (RSm) is 0.8 to 0.8. 10 μm, the maximum height roughness (Rz) is a micron-order roughness of 0.2 to 5 μm, and in the surface having the roughness, ultrafine irregularities with a period of 5 to 500 nm are formed, and The surface layer is a thin layer of metal oxide or metal phosphate.

  The laminated body of the metal of this invention 6 and carbon fiber reinforced resin in this invention 1-5 WHEREIN: The said adhesive agent is 1 liquid epoxy adhesive agent, It is characterized by the above-mentioned.

  In the method for producing a laminate of a metal and a carbon fiber reinforced resin according to the seventh aspect of the present invention, the three carbon fiber bundles are woven so as to have a predetermined angle with each other, and a predetermined shape is formed on the weave crossing alternately. A carbon fiber reinforced resin body forming step of forming a carbon fiber reinforced resin body by forming a triaxial fabric woven so as to have an opening portion to have a desired size, and a flat metal material, A metal body forming step in which a convex portion is formed at a position corresponding to the opening portion and the metal material on which the convex portion is formed is formed to have a desired size to form a metal body, and the carbon fiber reinforcement An application step of applying an adhesive to the joint surface of the resin body and the joint surface of the metal body, and the projecting portion of the metal body is inserted into the opening portion of the carbon fiber reinforced resin body, and the carbon Align the joint surface of the fiber reinforced resin body with the joint surface of the metal body. It turned into and is made from a bonding step of bonding.

  The manufacturing method of the laminated body of the metal of this invention 8 and carbon fiber reinforced resin is this invention 7, The said metal body formation process etches the said joint surface of the said metal body after forming the said convex part. Therefore, the surface has a roughness on the order of microns with an average interval between peaks and valleys (RSm) of 0.8 to 10 μm and a maximum height roughness (Rz) of 0.2 to 5 μm. In the in-plane, there is a step including a surface treatment step of performing a surface treatment in which ultra-fine irregularities with a period of 5 to 500 nm are formed and the surface layer is a thin layer of a metal oxide or a metal phosphate. The fiber reinforced resin body forming step is a step including a roughening step of performing a roughening treatment on the joint surface of the carbon fiber reinforced resin body after being formed to a predetermined size, and the coating step includes The joint surface subjected to the surface treatment of the metal body, and , A step of applying an adhesive to the bonding surface subjected to the roughening treatment of the carbon fiber reinforced resin body, and the bonding step is a step of applying the bonding surface of the carbon fiber reinforced resin body to the metal after the application step. An adhesion step for adhering to the joint surface of the body, and a curing step for curing the adhesive by heating while pressing the carbon fiber reinforced resin body and the metal body after the adhesion. To do.

  The manufacturing method of the laminated body of the metal of this invention 9 and carbon fiber reinforced resin is this invention 8 WHEREIN: The said adhesive agent is 1 liquid epoxy adhesive, The said 1 liquid epoxy adhesive is applied to the said application | coating process. After the coating, the pressure reduction / normal pressure return operation is performed several times, and the one-part epoxy adhesive is soaked into the joint surface of the metal body and the joint surface of the carbon fiber reinforced resin body. It is a process including processing.

  The laminate of the metal of the present invention and the carbon fiber reinforced resin is firmly bonded via an adhesive. In other words, convex portions are formed at predetermined intervals on the surface, a metal body that has improved tensile strength, bending rigidity, and torsional rigidity, and a carbon fiber bundle are woven into a triaxial woven fabric structure. Even if it acts, the carbon fiber bundle that can act in the direction in which the carbon fiber bundle in either direction increases the tensile strength is firmly bonded. As a result, due to the synergistic effect of both characteristics, the mechanical strength and rigidity were improved compared to the conventional plate-like structure. That is, it was possible to easily obtain a plate-like structure having significantly improved tensile strength, bending rigidity, and torsional rigidity.

  In addition, this laminate or a laminate as an application example of this laminate is suitable as a plate-like structural member that is thin, lightweight, and has improved thermal characteristics, mechanical strength, rigidity, and durability. It can be employed in the fields of automobiles, aircraft, electrical / electronic equipment, architecture, and the like. Furthermore, a laminated body having a pseudo honeycomb structure can be easily configured by combining the laminated bodies.

  The method for producing a laminate of a metal and a carbon fiber reinforced resin according to the present invention is a thin and lightweight laminate that has improved thermal characteristics, mechanical strength, rigidity, and durability. And a high-quality laminate can be produced. That is, the metal and the carbon fiber reinforced resin can be obtained by simply joining the metal body having the convex portion formed by press molding and the carbon fiber reinforced resin body in which the carbon fiber bundle is woven into the triaxial woven fabric structure with an adhesive. A laminate can be manufactured.

FIG. 1 is a plan view of a laminate of the metal of the present invention and a carbon fiber reinforced resin. 2 is a cross-sectional view taken along line AA in FIG. FIG. 3 is a cross-sectional view schematically showing a laminated state of a laminate of metal and carbon fiber reinforced resin, and is a cross-sectional view taken along line BB in FIG. FIG. 4 is a cross-sectional view showing a first laminate as an application example of a laminate of metal and carbon fiber reinforced resin. FIG. 5 is a cross-sectional view showing a second laminate as an application example of a laminate of metal and carbon fiber reinforced resin. FIG. 6 is a cross-sectional view showing a third laminate as an application example of a laminate of metal and carbon fiber reinforced resin. FIG. 7 is a cross-sectional view schematically showing a surface structure when a metal body and a one-component epoxy adhesive are joined.

  Hereinafter, the embodiment of the laminate of the metal of the present invention and the carbon fiber reinforced resin and the manufacturing method thereof will be described in detail based on the drawings.

FIG. 1 is a plan view of a laminate of a metal and a carbon fiber reinforced resin of the present invention, FIG. 2 is a cross-sectional view of FIG. 1 cut along line AA, and FIG. It is sectional drawing which showed the lamination | stacking state of the laminated body typically, and is sectional drawing which cut | disconnected FIG. 1 by the BB line.
FIG. 4 is a sectional view showing a first laminate as an application example of a laminate of metal and carbon fiber reinforced resin, and FIG. 5 is a second example of application of a laminate of metal and carbon fiber reinforced resin. FIG. 6 is a cross-sectional view showing a third laminate as an application example of a laminate of metal and carbon fiber reinforced resin. FIG. 7 is a cross-sectional view schematically showing a surface structure when a metal body and a one-component epoxy adhesive are joined.

  The laminate 10 of the present invention includes a carbon fiber reinforced resin made of a carbon fiber reinforced resin in which carbon fiber bundles 11, 12, and 13 having a flat cross section (or an elliptical shape or an oval shape) are woven into a triaxial woven fabric. A body (hereinafter referred to as a CFRP body) 10 and a metal body 20 are integrally joined with an adhesive 30.

[CFRP body]
The CFRP body 10 forms a triaxial woven fabric by weaving the carbon fiber bundles 11, 12, and 13 intersecting at an angle of 60 degrees. The second carbon fiber bundle 12 and the third carbon fiber bundle 13 which are warp yarns exist in the +60 degree direction and the −60 degree direction with respect to the axial direction, and the first carbon fiber bundle 11 which is the weft yarn in the width direction is inserted and woven. . The second carbon fiber bundle 12 and the third carbon fiber bundle 13 bend in the direction of 120 degrees at both ends. For example, the second carbon fiber bundle 12 in the +60 degree direction is changed to the third carbon fiber bundle 13 in the −60 degree direction, The third carbon fiber bundle 13 in the 60 degree direction becomes the second carbon fiber bundle 12 in the +60 degree direction, and weaving proceeds. The structure of the triaxial woven fabric has one carbon fiber bundle oriented in each direction. The woven first carbon fiber bundle 11 to the third carbon fiber bundle 13 are impregnated with an epoxy resin 14 as a matrix resin, and the CFRP body 10 constitutes a so-called sheet-like prepreg (see FIG. 3). ). Moreover, the CFRP body 10 should just be what the PAN type | system | group carbon fiber, the PITCH type | system | group carbon fiber, etc. were woven.

  The CFRP body 10 has a carbon fiber bundle in each direction every 60 degrees, and each carbon fiber bundle has a woven structure. Therefore, the CFRP body 10 is symmetric in the thickness direction and is a sheet having excellent pseudoisotropy. That is, the CFRP body 10 has a pseudo-uniform thermal modulus and mechanical properties such as elastic modulus and mechanical strength in the laminated surface. A hexagonal aperture 15 is formed in the middle of the woven structure of the first carbon fiber bundle 11, the second carbon fiber bundle 12, and the third carbon fiber bundle 13. The opening 15 is, for example, a hexagonal hole having a hexagonal dihedral width of 2 to 4 mm. The CFRP body 10 is made of carbon fiber reinforced resin woven into a triaxial woven fabric in a desired size and shape.

[Metal body]
The metal body 20 does not specifically limit the type of metal. However, considering weight reduction, it is preferable that the metal body be formed of a so-called light metal plate-like material having a low specific gravity such as aluminum or magnesium. The metal body 20 includes a flat portion 23 and convex portions 21 that are erected from the flat portion 23 at predetermined intervals. That is, convex portions 21 having a predetermined shape (in this embodiment, hexagonal shape) are formed at predetermined intervals on the plate material by press working. Note that the shape of the convex portion may be circular, elliptical, oval, other polygonal shapes, or the like. The convex portion 21 is formed at a position corresponding to the position of the opening portion 15 formed in the CFRP body 10, and is formed so as to be disposed in the opening portion 15. The height of the convex portion 21 is a height protruding from the CFRP body 10 by a predetermined amount (see FIG. 2). The height of the convex portion 21 is slightly higher than the CFRP body 10 or formed so as to be the same or substantially the same as the surface opposite to the joint surface of the CFRP body 10. Also good. The metal body 20 is formed by cutting a plate-like material on which the convex portions 21 are formed into a desired size and shape.

〔adhesive〕
In the present invention, the type of adhesive is not limited. However, in order to secure a stable adhesive force from room temperature to high temperature and to enhance the adhesive force with a metal body having three conditions of “NAT” to be described later, it is a one-component epoxy adhesive having a composition. It is preferable to use one that is optimized.

  The composition of the one-component epoxy adhesive preferable for use in the present invention is as follows. This one-part epoxy adhesive is composed of 60 parts of a bisphenol A-type epoxy resin mainly composed of a bisphenol A-type epoxy resin monomer when the total epoxy resin mixture constituting the one-part epoxy adhesive is 100 parts by mass. ˜75 parts by mass, 25 to 40 parts by mass of a polyfunctional type epoxy resin having 3 or more epoxy groups and having an aromatic ring. This epoxy resin mixture is composed of “(1) 60 to 75 parts by mass of a bisphenol A type epoxy resin monomer, (2) 0 to 15 parts by mass of a bisphenol A type epoxy resin oligomer, and (3) three or more epoxy groups. What is mixed is 25 to 40 parts by mass of an epoxy resin having a polyfunctional type and having an aromatic ring. 3 to 6 parts by mass of dicyandiamide powder as a curing agent is added to 100 parts by mass of this epoxy resin mixture, and 3- (3,4-dichlorophenyl) -1,1-dimethylurea powder as a curing aid. Is added to 1 to 3 parts by mass. It is preferable to add the curing agent and the curing aid after adding the following filler to the epoxy resin and mixing them.

  In this one-component epoxy adhesive, a filler is added to the basic composition described above. The filler to be added is a talc powder or clay powder having a particle size distribution center of 10 to 30 μm, an aluminum powder having a particle size distribution center of 10 to 30 μm, and a particle size distribution center of 10 to 10 μm. It is a polyethersulfone resin powder with a hydroxyl group of 30 μm. In particular, the adhesive strength can be improved by using aluminum powder.

  Moreover, the polyethersulfone resin powder with a hydroxyl group is added for the purpose of improving impact resistance. Even if 5-30 mass parts of polyethersulfone resin powder with a hydroxyl group whose particle size distribution center is 10-30 micrometers is added with respect to 100 mass parts of all the epoxy resins, it does not affect hardening performance and adhesive performance. Polyethersulfone resin is a thermoplastic resin with a melting point of 300 ° C or higher, and is sufficiently hard from room temperature to about 150 ° C, but creeps and deforms when applied with extreme force, so it is resistant to cured adhesives. Give sex. The amount of filler added is 100 parts by mass of the total epoxy resin, 5 to 20 parts by mass of talc powder or clay powder, 10 to 60 parts by mass of aluminum powder, and polyethersulfone resin powder with a hydroxyl group. 5 to 30 parts by mass.

  Based on this result, a laminate in which the CFRP body and the metal body are firmly bonded from room temperature to high temperature if the adhesion between the carbon fiber and the one-component epoxy adhesive at high temperature can be improved. Will be able to get. When the heat-resistant one-component epoxy adhesive developed by the present applicant is used, the adhesion between the carbon fiber and the one-component epoxy adhesive at 100 to 150 ° C. is not limited to normal temperature, and the carbon fiber and the matrix Since it exceeds the adhesive strength of the resin, a laminate in which the CFRP body and the metal body are firmly bonded from room temperature to high temperature can be obtained. This is because the one-component epoxy adhesive improved around the exposed carbon fiber is covered, and as a result, the heat resistance as a CFRP body can be improved.

[NAT theory]
The present applicant has proposed a method for obtaining a strong adhesive force by an anchor effect by forming a metal alloy surface in a predetermined shape and structure. The present applicant refers to this theory relating to adhesion as “NAT (Nano Adhesion Technology)”. In “NAT”, when the metal alloy surface satisfies the following three conditions, strong adhesion to the adherend can be achieved.

  (1) The first condition is that when the metal alloy surface is scanned with the latest dynamic mode scanning probe microscope, RSm is 0.8 to 10 μm and Rz is 0.2 to 5 μm. It is a measure. Here, RSm is an average length of the contour curve element defined in Japanese Industrial Standard “JIS B 0601: 2001” (ISO 4287: 1997), and Rz is Japanese Industrial Standard “JIS B 0601: 2001” (ISO 4287: 1997). This roughness surface is referred to as a “surface having a roughness on the order of microns”.

(2) The second condition is that ultrafine irregularities having a period of 5 nm or more are further formed on the surface of the metal alloy having a roughness on the order of microns. In order to satisfy the conditions, fine etching is performed on the surface of the metal alloy, and the inner wall surface of the recess having the roughness of the above-mentioned micron order is 5 to 500 nm, preferably 10 to 300 nm, more preferably 30 to 100 nm (optimum value). Form ultra-fine irregularities with a period of 50 to 70 nm.
(3) The third condition is that the surface layer of the metal alloy is ceramic. Specifically, with respect to the metal alloy type that originally has corrosion resistance, the surface layer needs to be a metal oxide layer having a thickness equal to or greater than that of the natural oxide layer, and the metal alloy type having relatively low corrosion resistance ( For example, in the case of a magnesium alloy or a general steel material, the third condition is that the surface layer is a thin layer of metal oxide or metal phosphorous oxide generated by chemical conversion treatment or the like.

  These are schematically illustrated as shown in FIG. A concave portion (C) having a roughness on the order of microns is formed on the surface of the joint surface 22 of the metal body 20, and an ultra fine irregularity (A) is formed on the inner wall of the concave portion. The surface layer is a ceramic layer. A part of the cured adhesive layer in which the adhesive 30 is cured has penetrated into the ultra-fine irregularities. When the liquid adhesive 30 penetrates into the surface of the metal alloy thus formed and is cured after the penetration, the metal alloy and the cured adhesive 30 are joined together very firmly.

[Surface treatment of metal bodies]
The joining surface 22 of the metal body 20 is subjected to a predetermined surface treatment in order to satisfy the three conditions of the “NAT” theory described above. The present applicant has disclosed a technique for surface treatment relating to various metals.

  For example, the present applicant has confirmed that “NAT” is applicable to metal alloy types mainly composed of aluminum, magnesium, copper, titanium, and iron. And the technique regarding an aluminum alloy is disclosed by "WO2008 / 114669 A1". A technique relating to a magnesium alloy is disclosed in “WO2008 / 133030 A1”. A technique related to a copper alloy is disclosed in “WO2008 / 126812 A1”. A technique relating to a titanium alloy is disclosed in “WO2008 / 133030 A1”. A technique related to stainless steel is disclosed in “WO2008 / 133296 A1”. A technique related to general steel materials is disclosed in “WO2008 / 146833 A1.” However, since “NAT” aims to improve adhesive strength by an anchor effect, it is not limited to at least these metal alloy types.

(Metal alloy that meets NAT requirements)
As a metal body to be joined to the CFRP body, a metal alloy having three conditions “NAT” is used. The metal alloy having a surface structure based on the above-described “NAT” is not particularly limited in theory. However, “NAT” can actually be applied to hard and practical metal alloys. Hereinafter, a surface treatment process for making the surface of the metal alloy into a surface structure conforming to the “NAT” condition will be described.
In order to facilitate understanding of this embodiment, a brief description will be given focusing on the surface treatment relating to the aluminum alloy.

(Chemical etching of metal bodies)
The chemical etching in this surface treatment process is intended to produce a roughness on the order of microns on the surface of the metal alloy. There are various types of corrosion, such as general corrosion, pitting corrosion, and fatigue corrosion, but it is possible to select an appropriate etching agent by selecting a chemical species that causes general corrosion for the metal alloy and performing trial and error. According to prior literature (for example, “Chemical Engineering Handbook (edited by Chemical Engineering Association)”), aluminum alloys are basic aqueous solutions, magnesium alloys are acidic aqueous solutions, stainless steel and general steel materials in general are hydrohalic acid such as hydrochloric acid, sulfurous acid, There is a description that the entire surface is corroded with an aqueous solution of sulfuric acid or a salt thereof.

  In addition, copper alloys with strong corrosion resistance can be corroded entirely by highly concentrated nitric acid aqueous solution or strongly acidic oxidizing acid such as hydrogen peroxide or oxidizer compound liquid, and titanium alloys are oxalic acid or hydrofluoric acid based Special books and patent literatures describe that it can be totally corroded with a special acid. The metal alloys that are actually sold in the market, such as pure copper-based copper alloys and pure titanium-based titanium alloys, have a purity of 99.9% or more and are hardly called alloys. Included in the alloy. Most of the metal alloys that are actually used are mixed with a wide variety of elements in order to obtain characteristic physical properties, and there are few pure metal materials, and they are substantially alloys.

  That is, most metal alloys are alloyed from pure metal for the purpose of improving corrosion resistance without deteriorating the original metal properties. Therefore, depending on the metal alloy, even if the acid / base or a specific chemical substance is used, the target chemical etching is often not possible. In practice, appropriate chemical etching is performed by trial and error while devising the concentration of the acid / base aqueous solution to be used, the liquid temperature, the immersion time, and, in some cases, the additive.

  Regarding the chemical etching method, “WO2008 / 114669 A1” describes a technology related to an aluminum alloy, “WO2008 / 133306 A1” refers to a technology related to a magnesium alloy, “WO2008 / 126812 A1” refers to a technology related to a copper alloy, and “WO2008 / 133030 A1”. "Technologies related to titanium alloys", "WO2008 / 133296 A1" describes technologies related to stainless steel, and "WO2008 / 146833 A1" describes technologies related to general steel materials.

  The points that are generally common in the work actually performed will be described. After shaping the metal alloy into a predetermined shape, the metal alloy is degreased by immersing it in an aqueous solution in which a degreasing agent for the metal alloy is dissolved and washed with water. This process is a process for removing most of the machine oil and finger grease adhering in the process of shaping the metal alloy, and it is preferably always performed. Then, it is preferably immersed in a thinly diluted acid / base aqueous solution and washed with water. This is a process that the present applicant refers to as preliminary acid cleaning and preliminary base cleaning. In the case of a metal alloy that corrodes with an acid such as a general steel material, it is immersed in a basic aqueous solution and washed with water. Further, in the case of a metal alloy that is particularly rapidly corroded with a basic aqueous solution such as an aluminum alloy, it is immersed in a dilute acid aqueous solution and washed with water. These are processes in which a solution opposite to the aqueous solution used for chemical etching is attached (adsorbed) to the metal alloy in advance, and the subsequent chemical etching starts without an induction period, so that the reproducibility of the process is remarkably improved. . Therefore, the preliminary acid cleaning and preliminary base cleaning steps are not essential, but are preferably employed in practice. After these steps, a chemical etching step is performed.

(Fine etching and surface hardening of metal bodies)
In addition, the fine etching in the surface treatment process aims to form ultra fine irregularities on the surface of the metal alloy. Moreover, the surface hardening process in this invention aims at making the surface layer of a metal alloy into a thin layer of a metal oxide or a metal phosphate. Depending on the type of metal alloy, nano-order fine etching may be performed at the same time by performing the chemical etching, and ultra-fine irregularities may be formed. Furthermore, depending on the type of metal alloy, the natural oxide layer on the surface may be thicker than the original and the surface hardening process may be completed. For example, a pure titanium-based titanium alloy is only subjected to chemical etching, so that the surface has a roughness on the order of microns and ultra-fine irregularities are also formed. That is, fine etching is performed together with chemical etching. However, in many cases, it is necessary to perform fine etching or surface hardening treatment after forming a large uneven surface on the order of microns by chemical etching.

[Roughening treatment of CFRP body]
When the CFRP body is bonded to the metal body, a stable adhesive force can be obtained by roughening the surface of the CFRP body. The surface can be polished with abrasive paper, for example, 80 to 480, preferably 120 to 240, as defined in Japanese Industrial Standard “JIS R 6252”. What grind | polished the surface about 10 to 20 times exhibits the high adhesive force stably. In order to remove dirt (fine powder) adhering to the roughened surface, the CFRP body is dipped in an aqueous solution containing a detergent and then dried. Alternatively, the dirt on the roughened portion may be removed with a strong water flow, soaked in tap water or pure water, washed, and dried. In the description of this embodiment, the method of polishing the surface with a polishing paper has been described. However, a method such as sandblasting may be used. That is, it is possible to use sandblast in place of abrasive paper in the mass production process.

  The CFRP body is preferably roughened to such an extent that part of the carbon fiber is exposed from the surface. This is because the adhesion between the carbon fiber and the one-component epoxy adhesive is generally superior to the adhesion between the carbon fiber and the matrix resin. When a commercially available one-component epoxy adhesive is used, the adhesion between the carbon fiber and the one-component epoxy adhesive is superior to the adhesion between the carbon fiber and the matrix resin at room temperature. However, at a high temperature of 100 ° C. or higher, the adhesive force between the commercially available one-component epoxy adhesive and the carbon fiber is sharply reduced, and breakage occurs between the one-component epoxy adhesive and the carbon fiber. That is, at a high temperature, not the adhesive force between the carbon fiber and the matrix resin in the CFRP prepreg used in the present invention, but a breakage is caused by a decrease in the adhesive force between the carbon fiber and the one-component epoxy adhesive.

[Infiltration treatment]
(Metal body soaking process)
After the adhesive (one-component epoxy adhesive) 30 is applied to the surface of the joint surface 22 of the metal body 20 satisfying the first condition to the third condition conforming to “NAT”, the metal body 20 is The container is sealed in a container such as a desiccator, and the pressure in the container is once reduced by a vacuum pump or the like and then returned to normal pressure. Specifically, the pressure in the container is reduced to about several tens of mmHg, the state is maintained for a predetermined time or longer (approximately several seconds to several minutes), and then air is introduced to return to normal pressure (or a pressure of several atmospheric pressure or higher) Pressure). The time for maintaining the reduced pressure state is adjusted according to the degree of penetration of the adhesive into the ultra-fine irregularities. This decompression / normal pressure return operation is preferably repeated a plurality of times. It is preferable that the container used for this decompression / normal pressure return operation, for example, a desiccator, is warmed to 50 to 70 ° C. before use. This is to reduce the viscosity of the applied adhesive so that it can easily penetrate into the ultra-fine irregularities on the surface. By setting the adhesive viscosity of the adhesive to 15 Pa seconds or less, preferably 10 Pa seconds or less, the ultra fine unevenness is caused to enter. The metal body soaked and processed is taken out of the container and placed in a hot air dryer to cure the adhesive.

  Here, when the viscosity of the adhesive (one-component epoxy adhesive) 30 to be applied to the surface of the joint surface 22 of the metal body 20 is low (for example, 10 Pa seconds or less), the pressure reduction / return to normal pressure is performed. There is a case where the adhesive 30 penetrates into the ultra fine irregularities without performing the operation. In this case, of course, the soaking process is unnecessary. Moreover, even if the viscosity of the adhesive 30 to be applied is high, the metal body 20 may be warmed to lower the viscosity of the adhesive after application, and may enter into the ultra-fine irregularities. Even in this case, the soaking process is unnecessary. The heating and the soaking process of the metal body 20 before the application of the adhesive 30 may be performed according to the degree of penetration of the adhesive into the ultra-fine irregularities.

(CFRP body soaking process)
After applying an adhesive (one-component epoxy adhesive) 30 to a predetermined location on the surface of the roughened CFRP body 10, the container is sealed in a container such as a desiccator, and the pressure in the container is vacuum pumped. For example, the pressure is reduced once, and then the pressure is returned to normal pressure. Specifically, the pressure in the container is reduced to about several tens of mmHg, the state is maintained for a predetermined time or longer (approximately several seconds to several minutes), and then air is introduced to return to normal pressure (or a pressure of several atmospheric pressure or higher) Pressure). The time in which the pressure is reduced is adjusted according to the degree of intrusion into the unevenness of the roughened portion of the adhesive 30. The purpose of this operation is to allow the adhesive 30 to penetrate into the unevenness of the joint surface of the CFRP body 10 caused by the roughening. That is, the adhesive (one-component epoxy adhesive) 30 is soaked into the cured epoxy resin obtained by curing the matrix resin of the CFRP body 10. In the case where the viscosity of the adhesive 30 after mixing the curing agent is as high as several tens of Pa seconds or more, the container used for the soaking and treatment is heated to 50 to 70 ° C. in advance. Thereby, the viscosity of the adhesive (one-component epoxy adhesive) 30 is set to 15 Pa seconds or less, preferably 10 Pa seconds or less.

  Here, when the viscosity of the adhesive 30 to be applied to the CFRP body 10 is low (for example, 15 Pa seconds or less), the adhesive 30 is roughened without performing the above-described decompression / normal pressure return operation. There is a case where the unevenness related to the portion is invaded. In this case, of course, the soaking process is unnecessary. Even if the viscosity of the adhesive 30 to be applied is high, the CFRP body 10 may be warmed to lower the viscosity of the adhesive 30 after application, and may enter the irregularities of the roughened portion. Even in this case, the soaking process is unnecessary. The heating and soaking process of the CFRP body 10 before application of the adhesive 30 may be performed according to the degree of penetration of the adhesive 30 into the unevenness.

[Bonding of CFRP body and metal body (aluminum alloy body)]
The procedure for joining the CFRP body 10 and the metal body 20 with the adhesive 30 will be described below.
First, on the plate-shaped material of the metal body (aluminum alloy) 20, convex portions 21 having a predetermined shape (in this embodiment, hexagonal shape) are formed at predetermined intervals by press working. The metal body 20 is formed by cutting the pressed plate-shaped material so as to have a desired size and shape. The joint surface 22 of the metal body 20 is etched so as to satisfy the above-mentioned “NAT” 3 condition (metal body forming step).

  Three carbon fiber bundles are woven so as to have a predetermined angle with each other, and a triaxial woven fabric woven so as to have openings of a predetermined shape on a weave that intersects with each other in a desired size, The CFRP body 10 is formed by cutting into a shape or the like. The joint surface of the CFRP body 10 is firmly polished 10 times with a 120th polishing paper prescribed in Japanese Industrial Standard “JIS R 6252” to roughen the surface. Next, an aqueous solution (60 ° C.) containing 7.5% of a degreasing agent for aluminum alloy “NE-6” is prepared in a tank in which an ultrasonic oscillator is installed, and an ultrasonic wave is oscillated into the rough surface. The converted CFRP body 10 is immersed for 5 minutes. Then, this CFRP body 10 is washed with water, put into a hot air dryer set at 80 ° C. for 15 minutes and dried (carbon fiber reinforced resin body forming step).

  An adhesive (one-component epoxy adhesive) 30 is applied to the joint surface 22 of the metal body (aluminum alloy body) 20. Further, the same adhesive (one-component epoxy adhesive) 30 is applied to the joint surface of the CFRP body 10 (application process). Thus, the metal body 20 and the CFRP body 10 to which the adhesive 30 is applied are placed in a desiccator. This desiccator was previously warmed by placing it in a warm air dryer at 67 ° C. for 15 minutes. Next, the pressure in the desiccator is reduced by a vacuum pump, maintained at a low pressure of 10 mmHg or less for about 3 minutes, and then returned to normal pressure. After this decompression / normal pressure return operation (soaking process) is performed a plurality of times, the metal body 20 and the CFRP body 10 are taken out of the desiccator.

The joining surface 22 of the metal body (aluminum alloy body) 20 and the joining surface of the CFRP body 10 were brought into close contact and fixed with clips. At this time, the convex portion 21 of the metal body 20 is inserted through the opening 15 of the CFRP body 10. These are put into a hot air dryer set at 90 ° C., heated to 135 ° C. and heated for 40 minutes. Then, after heating up to 165 degreeC and heating for 30 minutes, a power supply is turned off and it cools.
The joint surface of the CFRP body 10 and the joint surface 22 of the metal body 20 are firmly joined with an adhesive (one-component epoxy adhesive) 30 (joining step).

  In such a case, if the adhesive (one-component epoxy adhesive) 30 is liquid, the viscosity can be lowered with a slight increase in temperature even if the viscosity at normal temperature is high. It is possible to enter into the concave portion (the concave and convex portion in the first condition). Then, the invading adhesive (one-component epoxy adhesive) 30 is cured in the recess by subsequent heating. Actually, an ultra fine unevenness is further formed on the inner wall surface of the concave portion (the second condition), and the ultra fine unevenness is covered with a ceramic hard thin film (the third condition). For this reason, the epoxy resin that has entered and solidified into the recesses is difficult to be pulled out by being gripped by ultrafine irregularities such as spikes.

  In this laminated body 1, the metal body 20 and the CFRP body 10 are firmly bonded via an adhesive 30. That is, convex portions are formed at predetermined intervals on the surface, and the metal body 20 that improves the tensile strength, bending rigidity, and torsional rigidity, and the carbon fiber bundle are woven into the triaxial woven fabric structure, and the load from which direction The CFRP body 10 that can act in the direction in which the carbon fiber bundles in either direction increase the tensile strength even when the is acted on is firmly joined. Due to the synergistic effect of both properties, the thermal properties, mechanical strength, and rigidity can be improved with a thin wall and light weight. That is, it is possible to easily obtain the laminate 1 having a significantly improved tensile strength, bending rigidity, and torsional rigidity as a plate-like structure.

Based on FIGS. 4-6, the laminated body 51, 61, 71 suitable for a structural member as an application example of the laminated body 1 is demonstrated.
As shown in FIGS. 4 and 5, when two laminated bodies 1 are face-to-face or back-to-back bonded with an adhesive 55, a laminated body 51 and a laminated body 61 suitable for a structural member similar to a honeycomb structure are used. Can be obtained. For example, when the surfaces 52a and 52b of the planar portion 23 of the laminates 1 and 1 are joined with the adhesive 55, the laminate 51 shown in FIG. Further, when the back surface alignment, that is, the surfaces (convex surface top surfaces) 62a and 62b of the convex portions 21 of the multilayer bodies 1 and 1 are joined with the adhesive 55, the multilayer body 61 shown in FIG.

These laminated bodies 51 and 61 can be further improved in strength from the laminated body 1 alone. That is, it is possible to obtain laminates 51 and 61 suitable for a structural member having a light weight, high mechanical strength, and high rigidity. Moreover, since the CFRP body 10 appears on the outer periphery, the laminate 51 is excellent in aesthetics and the like.
The adhesive 55 may be a general adhesive. However, in order to secure a stable adhesive force from room temperature to high temperature and to increase the adhesive force with the metal body having the above-mentioned “NAT” conditions, the above-described one-component epoxy adhesive is used. It is preferable. Further, the surfaces 52a and 52b and the surfaces 62a and 62b may be subjected to the surface treatment as described above.

  As shown in FIG. 6, the laminated body 71 is obtained by bonding the second metal body 25 to the laminated body 1 with an adhesive 56. The second metal body 25 is a flat plate, and a hole portion 25 a is formed at a position corresponding to the convex portion 21. And when the 2nd metal body 25 is joined to the laminated body 1, the convex part 21 has penetrated the hole 25a. One surface of the CFRP body 10 is bonded to the metal body (first metal body) 20 with an adhesive 30. In addition, one surface of the second metal body 25 is bonded to the other surface of the CFRP body 10 with an adhesive 56. By joining in this way, the laminated body 71 in which the first metal body 20, the CFRP body 10, and the second metal body 25 are integrally joined in a sandwich shape can be obtained. Although this laminated body 71 is also substantially planar, it can be set as a laminated body suitable for a lightweight, high mechanical strength, and highly rigid structural member. 6 shows an example in which the height of the convex portion 21 protrudes from the lower surface (the other surface) of the second metal plate 25, the height is the same as or substantially the same as the lower surface of the second metal plate 25. The thing of the same height may be sufficient.

  The adhesives 30 and 56 may be general adhesives. However, in order to secure a stable adhesive force from room temperature to high temperature and to increase the adhesive force with the metal body having the above-mentioned “NAT” conditions, the above-described one-component epoxy adhesive is used. It is preferable. In addition, the bonding surface of the first metal body 20, the bonding surface of the second metal body 25, and the bonding surface of the CFRP body 10 are preferably subjected to the surface treatment and the roughening treatment as described above. .

  Although the embodiment of the present invention has been described above, the present invention is not limited to this embodiment. Needless to say, changes can be made without departing from the scope and spirit of the present invention. For example, the convex portions of the metal body may not be entirely present at the positions corresponding to the positions of the opening portions of the CFRP body. The convex part of the metal body may be formed for each of a plurality of apertures of the CFRP body.

DESCRIPTION OF SYMBOLS 1 ... Laminated body 10 ... Carbon fiber reinforced resin body (CFRP body)
DESCRIPTION OF SYMBOLS 11 ... 1st carbon fiber bundle 12 ... 2nd carbon fiber bundle 13 ... 3rd carbon fiber bundle 15 ... Opening part 20 ... Metal body (1st metal body)
21 ... Convex part 23 ... Planar part 25 ... Second metal bodies 30, 55, 56 ... Adhesives 51, 61, 71 ... Laminate

Claims (9)

Carbon formed in a triaxial woven fabric in which three carbon fiber bundles are woven so as to have a predetermined angle with each other, and have a predetermined-shaped opening in a texture that crosses alternately. A fiber-reinforced resin body;
A metal body laminated on the carbon fiber reinforced resin body, a metal body having a convex portion formed at a position corresponding to the opening portion;
It consists of an adhesive for integrally bonding the carbon fiber reinforced resin body and the metal body,
The said convex part is located in the said opening part. The laminated body of the metal and carbon fiber reinforced resin characterized by the above-mentioned. In the laminated body of the metal and carbon fiber reinforced resin described in claim 1,
One laminate in which the carbon fiber reinforced resin body and the metal body are integrally joined, and the other laminate in which the carbon fiber reinforced resin body and the metal body are integrally joined are the metal body. A laminate of a metal and a carbon fiber reinforced resin, characterized by being joined at a flat surface portion or a convex upper surface of the convex portion. Carbon formed in a triaxial woven fabric in which three carbon fiber bundles are woven so as to have a predetermined angle with each other, and have a predetermined-shaped opening in a texture that crosses alternately. A fiber-reinforced resin body;
A metal plate laminated on one side of the carbon fiber reinforced resin body, a first metal body having a convex portion formed at a position corresponding to the opening portion;
A metal plate laminated on the other side of the carbon fiber reinforced resin body, the second metal body having a hole formed at a position corresponding to the opening,
A laminate of a metal and a carbon fiber reinforced resin, comprising: an adhesive for integrally bonding the carbon fiber reinforced resin body, the first metal body, and the second metal body. In the laminated body of the metal and carbon fiber reinforced resin as described in any one of Claim 1 to 3,
The bonded surface of the carbon fiber reinforced resin body is a surface subjected to a roughening treatment. A laminate of a metal and a carbon fiber reinforced resin. In the laminated body of the metal and carbon fiber reinforced resin as described in any one of Claim 1 to 4,
The joint surface of the metal body is etched so that the average interval between peaks and valleys (RSm) is 0.8 to 10 μm and the maximum height roughness (Rz) is 0.2 to 5 μm. In the surface having the roughness, ultra-fine irregularities with a period of 5 to 500 nm are formed, and the surface layer is a thin layer of metal oxide or metal phosphate. Laminate with carbon fiber reinforced resin. In the laminated body of the metal and carbon fiber reinforced resin as described in any one of Claim 1 to 5,
The adhesive is a one-component epoxy adhesive. A laminate of a metal and a carbon fiber reinforced resin. Three carbon fiber bundles are woven so as to have a predetermined angle with each other, and a triaxial woven fabric woven so as to have an opening of a predetermined shape is formed in a desired size. A carbon fiber reinforced resin body forming step to form a carbon fiber reinforced resin body,
A metal body in which a convex portion is formed on a flat metal material at a position corresponding to the opening, and the metal material on which the convex portion is formed is formed to have a desired size. Forming process;
An application step of applying an adhesive to the bonding surface of the carbon fiber reinforced resin body and the bonding surface of the metal body;
A joining step of inserting the convex portion of the metal body into the opening portion of the carbon fiber reinforced resin body and integrally joining the joint surface of the carbon fiber reinforced resin body and the joint surface of the metal body. A method for producing a laminate of a metal and a carbon fiber reinforced resin. In the manufacturing method of the laminated body of the metal and carbon fiber reinforced resin described in Claim 7,
In the metal body forming step, after forming the convex portion, the joint surface of the metal body is etched to make the surface have a mean valley interval (RSm) of 0.8 to 10 μm and a maximum height roughness. The thickness (Rz) has a roughness on the order of microns of 0.2 to 5 μm. Ultra fine irregularities with a period of 5 to 500 nm are formed in the surface having the roughness, and the surface layer is oxidized by metal. It is a process including a surface treatment process for performing a surface treatment to make a thin layer of an object or a metal phosphate,
The carbon fiber reinforced resin body forming step is a step including a roughening step of performing a roughening treatment on the joining surface of the carbon fiber reinforced resin body after being formed to a predetermined size,
The application step is a step of applying an adhesive to the joint surface subjected to the surface treatment of the metal body and the joint surface subjected to the roughening treatment of the carbon fiber reinforced resin body,
The bonding step includes, after the application step, an adhesion step of attaching the bonding surface of the carbon fiber reinforced resin body to the bonding surface of the metal body, and after adhesion, heating while holding the carbon fiber reinforced resin body and the metal body. And a curing step for curing the adhesive. A method for producing a laminate of a metal and a carbon fiber reinforced resin, characterized by comprising: In the manufacturing method of the laminated body of the metal and carbon fiber reinforced resin described in Claim 8,
The adhesive is a one-component epoxy adhesive,
In the application step, after applying the one-component epoxy adhesive, the pressure reduction / normal pressure return operation is performed a plurality of times, and the metal body and the carbon fiber reinforced resin body are joined to each other. The method for producing a laminate of a metal and a carbon fiber reinforced resin, wherein the one-component epoxy adhesive is soaked and the process includes a soaking process.

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