JP2019151090A - Conjugate of metal and resin material - Google Patents

Abstract

To provide a conjugate of a metal and a resin material capable of enhancing conjugation strength of the conjugate of the metal and the resin material, capable of suppressing deterioration of conjugation strength even when repeated heat stress is applied on the conjugate, and high in durability.SOLUTION: There is provided a conjugate of a metal and a resin material, in which a plating film with a rough surface structure is arranged on a surface of the metal, and the metal and the resin material are integrally conjugated via the plating film with the rough surface structure. As the plating film with the rough surface structure, a composite plating film of a carbon nanotube, or a plating film with a random thin sheet structure is arranged.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a joined body of a metal and a resin material, and more specifically, relates to a joined body of a metal and a resin material in which a joining force between the metal and the resin material is reinforced.

A joined body of a metal and a resin material is widely used as a structural material in various industrial fields such as electric / electronic products and automobiles. As an example of a joined body of metal and resin material, for example, a joined body of metal and a new material such as carbon fiber reinforced plastic (CFRP) is lighter in weight, specific strength, and heat resistance. There is an advantage that it is excellent in the point of.
However, the bonded body of metal and resin material has a problem in terms of bonding strength against heat history and bonding durability because the thermal expansion coefficients of the metal and resin material are greatly different.

As a method for improving the bonding strength of a metal / resin material, a method of improving the bonding strength by roughening the metal bonding surface (unevenness processing) and integrating the metal and the resin material. Proposed. As a method for roughening the metal joint surface, a method of forming irregularities on the metal surface by pressing using a mold with fine irregularities, chemical etching, anodizing, sand blasting, liquid honing is used. (Patent Document 1), a method of forming a rough surface by laser processing (Patent Document 2), and the like.
Also, as a method different from the method of processing and treating the metal material itself, unevenness is provided on the surface of the metal using plating, and the metal and the resin material are integrated and bonded using the unevenness provided by plating. The method of making it also has been proposed (Patent Documents 3 and 4).
The reason why the bonding strength is improved by integrating the metal and the resin material using the rough surface (unevenness) provided on the surface of the metal is that the bonding area between the metal and the resin material is increased, the metal and the resin Due to the anchor effect acting between the materials.

JP 2011-224974 A Japanese Patent Laying-Open No. 2015-116684 JP 2017-711165 A JP 2017-89004 A JP 2007-9333 A JP 2015-42776 A JP-A-2006-56401 JP 2017-82286 A

As a method to improve the joint strength of the metal / resin material, the contact area between the metal and the resin material is increased by roughening the metal surface or forming a rough surface by plating on the metal surface. In addition, the method for enhancing the bonding force by the anchor action can obtain a desired bonding strength with respect to the initial bonding strength between the metal and the resin material.
However, the most important issue regarding the joint strength of the joined body is that the thermal stress acting on the joined body repeatedly acts on the joined body due to fluctuations in the temperature of the joined body, and the joined strength of the joined body gradually deteriorates. It is impossible to maintain the bonding strength.
The present invention increases the bonding strength of a bonded body of a metal and a resin material, and can suppress deterioration of the bonding strength even when a repeated thermal stress is applied to the bonded body. It is an object to provide a joined body.

The joined body of the metal and the resin material according to the present invention is provided with a plating film having a rough surface structure on the surface of the metal, and the metal and the resin material are integrally bonded via the plating film of the rough surface structure. It is characterized by being made.
Further, a base plating film is provided on the surface of the metal, and the plating film having the rough surface structure is provided on the base plating film.
In addition, a plating film having a carbon nanotube composite plating film is suitable as the plating film having the rough surface structure.
In addition, a plating film having a random thin plate structure is suitable as the plating film having the rough surface structure. The plating film with a random thin plate structure can have a grainy rough structure different from the thin plate shape by adjusting the plating conditions such as the concentration of the additive (polyacrylic acid) added to the plating bath, or the granular and thin plate. It can be formed in a mixed form. By controlling the rough surface structure of the plating film, the bondability (anchor effect) between the plating film and the resin can be controlled. For example, by using a granular rough surface structure, a joined body having a large breaking strength can be obtained. Obtainable.
In addition, since the plating film having a random thin plate structure is a plating film having a random thin plate structure in which carbon nanotubes are incorporated into the plating film, the bonding strength between the metal and the resin material can be improved.

  The joined body of the metal and the resin material according to the present invention is formed by integrating the metal and the resin material through a rough plating film provided on the surface of the metal. Can be provided as a joined body in which the metal and the resin material are firmly joined.

It is the SEM image of the state which gave the composite plating of the carbon nanotube to the surface of a steel plate. It is explanatory drawing which shows the method of forming a plating film on the surface of a metal and integrating a metal and a resin material through a plating film. It is explanatory drawing which shows the conventional method which makes a metal surface an uneven surface, integrates a metal and a resin material, and forms a conjugate | zygote. It is the SEM image which looked at the plating film of the random thin plate structure provided on the metal of the board | substrate from the surface direction and the cross-sectional direction. They are a surface SEM image and a cross-sectional SEM image of what provided the plating film of the random thin plate structure on the copper substrate, and what provided the base nickel plating film and the plating film of the random thin plate structure on the copper substrate. 2 is an SEM image of a plating film having a random thin plate structure formed by incorporating carbon nanotubes into a plating film on a substrate. Cross-sectional SEM image of a random thin plate structure plating film prepared by electrolytic copper plating, SEM image when a random thin plate structure plating film is further plated with tin, electron beam micro showing the copper distribution and tin distribution of the plating film It is a figure which shows the measurement result of an analyzer (EPMA). It is explanatory drawing which shows the method of integrating a metal and a resin material through the plating film of a random thin plate structure. It is a figure which shows the structure of the sample used for the evaluation test of joining strength. 2 is a graph showing the SEM image of the surface of the plated surface and the surface roughness of the plated surface when the carbon nanotube is not added (a) and when the carbon nanotube is added (b). . 4 is a surface SEM image of a plating film when the amount of carbon nanotube added is 0.25 gL ⁻¹ , 0.5 gL ⁻¹ , 1.0 gL ⁻¹ , and 2.0 gL ⁻¹ . It is a graph which shows the result of having measured the breaking strength about the test sample created using the base material which gave composite plating, and the base material which has not given composite plating. It is a graph which shows the measurement result of the breaking strength about the test sample shown in Table 1. It is a SEM image of the joint surface before and after a test sample is fractured. It is a SEM image which expands and shows the form of the joint surface of a test sample more. FIG. 2 is a cross-sectional SEM image (a) of an interface between a plating film and a resin, and an EDS mapping diagram (b) of the cross section. It is the graph which shows the surface SEM image of the plating film of a rough surface structure, and a surface ancestry degree. It is a graph which shows the breaking strength obtained by the tensile shear test. It is a cross-sectional SEM image of the interface of a plating film and resin. It is a graph which shows the EDS analysis result of the interface vicinity of a plating film and resin. It is a SEM image of the fracture surface on the substrate side before and after fracture. It is a SEM image of the fracture surface on the resin side after fracture. It is a photograph which shows the mode of the test which heats the conjugate | zygote which integrally molded the metal and the resin material, and isolate | separates a metal and a resin material. (a) is an external appearance photograph of the base material (metal) after separation, and the range where the metal and the resin are joined is indicated by a broken line. (b) is a surface SEM image (b) of the bonded portion. (a) is the external appearance photograph of the resin molding part after isolation | separation, and the broken line shows the site | part joined with the base material. (b) is a surface SEM image of the bonded portion. It is the surface SEM image of the composite plating film | membrane of the nickel-carbon nanotube provided in the surface of the base material. It is a photograph which shows the mode of the test which heats the conjugate | zygote which integrally molded the metal and the resin material, and isolate | separates a metal and a resin material. (a) is an external appearance photograph of the base material (metal) after separation, and the range where the metal and the resin are joined is indicated by a broken line. (b) is a surface SEM image (b) of the bonded portion. (a) is the external appearance photograph of the resin molding part after isolation | separation, and the broken line shows the site | part joined with the base material. (b) is a surface SEM image of the bonded portion.

(Embodiment 1)
1st Embodiment of the joined body of the metal and resin material which concerns on this invention is equipped with the composite plating film of a carbon nanotube as a plating film provided with the rough surface structure on the surface of a metal, The said metal and resin material are , And are integrally joined via the plating film having the rough surface structure.
The composite plating film of carbon nanotubes is formed by suspending carbon nanotubes in a plating bath and incorporating the carbon nanotubes into the plating film. As the carbon nanotubes used for the composite plating of carbon nanotubes, single-walled carbon nanotubes, multi-walled carbon nanotubes, cup-stacked carbon nanotubes, and the like can be used. Multi-walled carbon nanotubes are carbon nanotubes having a multi-layer structure of two or more layers.

  Single-walled carbon nanotubes, multi-walled carbon nanotubes, cup-stacked carbon nanotubes, and the like are provided by a plurality of manufacturers. Carbon nanotube products have different properties depending on the manufacturer, but in the present invention, carbon nanotube products can be appropriately selected and used. In this specification, these carbon nanotube products are collectively referred to as carbon nanotubes.

Plating metals used for carbon nanotube composite plating include Au, Pt, Ag, Cu, Ni, Co, Zn, Fe, Sn, Ni-P, Ni-B, Ni-W, Ni-WP, Fe-P And alloys such as Co-W.
A combination of these plated metals (including alloys) and carbon nanotubes (single-layer, multi-layer, cup-stack type) can be arbitrarily selected.
The plating metal and carbon nanotube used for the composite plating film may be appropriately selected from the plating metal and the carbon nanotube product in consideration of the bonding strength when the bonded body is used.

The composite plating film of carbon nanotubes can be formed on the metal surface using an electrolytic plating method. The thickness of the composite plating film and the amount of carbon nanotubes to be contained in the composite plating film can also be appropriately set in consideration of the bonding strength between the metal and the resin material.
The method of forming a plating film using a plating method is to form a plating film having a desired form and characteristics by appropriately controlling the plating conditions without depending on the material and type of the underlying metal. There is a big advantage that you can.

The carbon nanotube composite plating film formed as a rough plating film can be formed directly on the surface of the metal, or can be provided on the surface of the metal in advance and provided on the base plating. .
When a plating film is provided on the surface of a metal by plating, the adhesion strength between the metal surface and the plating film greatly affects the bonding strength of the joined body. If there is a risk of insufficient adhesion (bonding strength) between the metal of the joined body (base metal) and the metal to be used for composite plating, both the metal and the plated metal of the composite plating film are good. A metal having good adhesion may be selected, a base plating film may be provided on the metal, and a composite plating film of carbon nanotubes may be provided on the base plating film.

  The reason why the base plating film is provided on the carbon nanotube composite plating film is that the adhesion between the metal and the carbon nanotube composite plating film is improved and the bonding strength is improved. When the thermal expansion coefficient of the composite plating film is significantly different, it can be provided for the purpose of relaxing the thermal stress generated between the metal and the composite plating film. By using a metal having a thermal expansion coefficient intermediate between those of the metal and the composite plating film as a base plating film, the thermal stress generated between the metal and the composite plating film of carbon nanotubes is alleviated. The durability of the bonding strength of the bonded body with the resin material can be improved.

FIG. 1 shows an example in which a surface of a base metal (steel plate: SPCC) is subjected to nickel composite plating using multi-walled carbon nanotubes as a composite plating film of carbon nanotubes to form a rough plating film. FIG. 1 (a) is an SEM image of a nickel composite plating film of multi-walled carbon nanotubes as seen from a plane direction, and FIG. 1 (b) is an SEM image as seen from a cross-sectional direction.
From FIGS. 1 (a) and 1 (b), the surface of the composite plating film is formed on a fine uneven surface, multi-walled carbon nanotubes are randomly taken into the composite plating film, and from the surface of the composite plating film. It can be seen that the carbon nanotubes are supported by the plating film so that the tip of the multi-walled carbon nanotubes protrudes.

(Bonded metal and resin material)
A joined body of a metal and a resin material is formed by providing a composite plating film of carbon nanotubes on the surface of the metal and integrating the metal and the resin material via the composite plating film.
FIG. 2 shows a method of forming a joined body by integrating a metal and a resin material.
FIG. 2A shows a state in which a composite plating film 12 of carbon nanotubes is provided on the metal 10 of the base material as a plating film having a rough surface structure. In FIG. 2 (a), in order to illustrate that the unevenness is formed on the surface of the composite plating film, the base of the carbon nanotube 14 is embedded in the plating film, and the tip protrudes from the plating film. It is shown as a form in which the carbon nanotubes 14 are supported by rectangular protrusions and protrusions. Actually, as shown in FIG. 1, the composite plating film has a complicated uneven shape, and the carbon nanotubes 14 are taken into a random shape.

  FIG. 2B shows a state in which the resin material 20 is integrated with the base metal 10 through the composite plating film 12 of carbon nanotubes. The illustrated resin material 20 is a thermoplastic carbon fiber reinforced plastic (CFRTP). In this example, the resin material 20 is integrally formed on the surface of the metal 10 by insert molding. The resin material 20 is a composite material of the carbon fiber 21 and the resin 22, and the metal 10 and the resin material 20 are integrated through the composite plating film 12 of carbon nanotubes by insert molding. In FIG. 2 (b), the carbon fiber 21 is depicted in a diagram in which the carbon fiber 21 is laminated in parallel to the surface of the metal 10 that is the base material.

  In FIG. 2 (b), the characteristic structure is that in the operation of integrating by insert molding, the resin 20 constituting the resin material (CFRTP) 20 enters the gaps between the irregularities of the composite plating film 12 of carbon nanotubes, and the gaps are formed. The metal 10 and the resin material 20 are integrated so as to be filled. The carbon fiber 21 is far longer than the unevenness of the carbon nanotube composite plating film 12, and the carbon fiber 21 is disposed slightly apart from the carbon nanotube composite plating film 12. The unevenness of the plating film and the vicinity of the unevenness are filled with the resin 22.

  Since the unevenness provided on the composite plating film 12 of carbon nanotubes has a random and extremely complicated form, the contact area between the resin 22 and the composite plating film 12 of carbon nanotubes is extremely large, thereby the composite plating of the resin 22 and the carbon nanotubes. This contributes to improving the bonding strength with the film 12. Further, the unevenness formed on the composite plating film 12 of carbon nanotubes has an anchoring action that reverses the direction in which the resin material 20 is separated from the metal 10, so that the bonding strength between the metal 10 and the resin material 20 is thereby increased. Can be improved.

  Further, the carbon nanotubes 14 of the composite plating film 12 of carbon nanotubes are integrally formed with the tips protruding into the resin 22, and the bonding action between the resin 22 and the carbon nanotubes 14 results in the composite plating film 12 of the resin 22 and carbon nanotubes. It is further added as an effect of linking. In this way, the bonding strength between the base metal 10 and the resin material 20 can be improved by bonding the resin 22 through the carbon nanotube composite plating film 12.

Further, regarding the thermal expansion coefficient of the base metal 10 and the resin material 20, the thermal expansion coefficient of the metal is 1 × 10 ⁻⁵ / K, whereas the thermoplastic resin used for the resin material 20 is The coefficient of thermal expansion is about ^{5 to} 10 × 10 ⁻⁵ / K (PP = 6 to 10 × 10 ⁻⁵ / K, PA6 = 6 to 10 × 10 ⁻⁵ / K, PPS: = 5 × 10 ⁻⁵ / K K). On the other hand, since the carbon nanotubes 14 constituting the composite plating film 12 of carbon nanotubes have a thermal expansion coefficient of approximately 0 × 10 ⁻⁵ / K, the composite plating film 12 of carbon nanotubes has the thermal expansion coefficient of the resin material 20 as a metal. It acts to approach a thermal expansion coefficient of 10. Thus, the composite plating film 12 of carbon nanotubes acts so as to match the thermal expansion coefficients of the metal 10 and the resin material 20, and suppresses thermal stress generated in the joined body when the joined body changes in temperature. Acts to improve the durability.

FIG. 3 shows a conventional method in which the metal 10 of the base material is etched or laser-treated to form irregularities 10a on the surface of the metal 10 and the metal 10 and the resin material 20 are integrated by insert molding. In this example, since the irregularities 10a are only formed on the surface of the metal 10, the resin material 20 is filled with the resin 22 constituting the resin material 20 in the irregularities 10a so that the metal 10 and the resin material 20 Are joined.
The bonding force between the metal 10 and the resin material 20 is due to an adsorption action due to a large contact area between the unevenness 10a formed on the surface of the metal 10 and the resin 22, and an anchoring action of the unevenness 10a.

In the case of the bonding method shown in FIG. 3, compared to the bonding method of the embodiment shown in FIG. 2B, the resin 22 is connected through the carbon nanotubes 14, thereby the metal 10 and the resin material 20. It lacks the effect of enhancing the bonding force.
In the example shown in FIG. 3, the metal 10 and the resin material 20 are directly connected, and the thermal stress due to the difference in thermal expansion coefficient directly acts between the metal 10 and the resin material 20. On the other hand, in the example shown in FIG. 2 (b), the thermal stress acting between the metal 10 and the resin material 20 by interposing the composite plating film 12 of carbon nanotubes between the metal 10 and the resin material 20. Can be relaxed, and durability when a thermal cycle repeatedly acts on the joined body can be improved.

(Second Embodiment)
In the second embodiment of the metal / resin-bonded body according to the present invention, a thin plate-like plating film is randomly mixed and deposited on the surface of the metal as a rough surface plating film. A plating film having a random thin plate structure is provided, and the metal and the resin material are integrally joined via the plating film having the rough surface structure.
FIG. 4 shows an example in which a plating film having a random thin plate structure is provided as a rough surface plating film on the surface of a metal serving as a base material. The plating film having a random thin plate structure can be formed by electrolytic plating. In FIG. 4, a copper plate is used as the base metal.

FIG. 4 shows an example in which a plating film having a random thin plate structure is provided on a metal (base material) by changing an energization amount to be energized during electrolytic plating.
A plating film having a random thin plate structure can be formed by controlling the plating conditions under which the plating metal is deposited in a thin plate shape when the plating metal is deposited. The present inventor has reported that a plating film having a random thin plate structure can be formed by controlling plating conditions during electrolytic copper plating (Patent Documents 6 and 7).

FIG. 4 shows an SEM image of a plating film having a random thin plate structure on the metal of the substrate as viewed from the surface direction and the cross-sectional direction.
As shown in FIG. 4, the plating film having a random thin plate structure grows from the surface of the base material (metal) so that the plating metal extends in the form of a thin plate while maintaining the thin plate surface direction. On the other hand, in order to grow in an inclined manner, when the plating is advanced, the thin plate-like plated metals are in a random form in which they are intricately mixed with each other.
A plating film having a random thin plate structure is characterized in that it is a space between thin plates made of plated metal, and is formed in a crossed form in which a large number of thin plates are randomly projected.

In FIG. 4, when the current density at the time of electrolytic plating is low, the space | interval of the metal plate which deposits becomes wide, and when a current density is made high, it shows that the space | interval of a thin plate becomes narrow.
The thickness of the thin plate formed by the plating metal is about 0.03 μm to 0.5 μm, and the distance between the thin plates is about 0.5 μm to 2 μm.
As shown in FIG. 4, by selecting the plating conditions, it is possible to adjust the plating thickness of the plating film having the random thin plate structure, the arrangement density (interval) of the thin plates having the thin plate structure, and the thickness of the thin plate.

A random thin plate structure plating film formed as a rough surface plating film can be formed directly on the surface of a metal (base material), or a base plating is provided in advance on the surface of the metal, and this plating film is formed on the base plating film. It can also be provided.
FIG. 5 shows an example in which a plating film having a random thin plate structure is provided using a copper plate as a base material, and an example in which a nickel plating film is formed as a base plating on a copper plate base material and a plating film having a random thin plate structure is formed thereon. Show. The plating film having a random thin plate structure was formed by electrolytic copper plating.

Depending on the type of metal of the base material that constitutes the joined body, a base plating film is provided and a base surface plating film is provided with a rough surface structure rather than a metal surface having a rough surface structure. However, there are cases where the bonding strength of the entire bonded body can be improved. In such a case, by appropriately providing a base plating film, it is possible to enhance the bonding strength of the bonded body and improve the durability of the bonded body.
As described above, in addition to improving the bonding strength, the effect of the base plating film is to match the thermal expansion coefficients of the base metal and the resin material (thermal stress due to different thermal expansion coefficients). It is also possible to select a metal to be used for the base plating film from the viewpoint of the coefficient of thermal expansion.

As shown in FIG. 5, the method of providing a plating film having a random thin plate structure by electrolytic plating does not cause a problem even when a base plating film is provided. A plating film having a random thin plate structure can be provided on the film.
From FIG. 5, it can be seen that the plated metal is grown in a thin plate shape and formed in a state of crossing each other.

(Other forms of plating film with random thin plate structure)
Although the plating film having the roughened structure described above is an example of a plating film having a random thin plate structure, another example of the plating film having a random thin plate structure is plated with carbon nanotubes in the same manner as the composite plating of carbon nanotubes. There is a method of forming a plating film having a random thin plate structure incorporated in the film. A plating film having a random thin plate structure in which carbon nanotubes are incorporated into the plating film can be produced by the method proposed by the present inventor (Patent Document 8).

  FIG. 6 shows an example of a plating film having a random thin plate structure formed by incorporating carbon nanotubes into a plating film on a copper substrate by electrolytic copper plating. The configuration in which carbon nanotubes are incorporated into a plating film having a random thin plate structure is the same as the case of simple electrolytic copper plating with respect to the form in which plated metal (copper) is deposited in a thin plate shape and the thin plates are randomly interlaced. The feature of the structure of the plating film of random thin plate structure formed by incorporating carbon nanotubes into the plating film is that the carbon nanotubes incorporated into the plating film penetrate through multiple thin plates and span between multiple thin plates This is a point to be connected.

A plating film with a random thin plate structure formed by incorporating carbon nanotubes into the plating film is plated compared to the case of only plating metal because thin plates made of plating metal are connected like carbon by carbon nanotubes. It is thought that the strength of the film can be improved.
In addition, since carbon nanotubes are taken in between the thin plates, when the base metal and the resin material are integrated, there is a physical action that prevents the resin material from peeling off the plating film. It is possible to work.
By these actions, the bonding strength between the metal of the base material and the resin material can be enhanced by providing a plating film with a random thin plate structure formed by incorporating carbon nanotubes into the plating film as a plating film with a rough surface structure. Is possible.

As yet another configuration example of a plating film with a rough surface structure, after forming a plating film with a random thin plate structure by appropriately setting plating conditions, another metal is plated on the plating film with a random thin plate structure and deposited on the random thin plate There is a method of making (supporting).
FIG. 7 shows a cross-sectional SEM image of a plating film with a random thin plate structure produced by electrolytic copper plating, a cross-sectional SEM image when the tin plating is further applied to the plating film with a random thin plate structure, and the copper distribution and tin of the plating film. The result of having analyzed distribution of this using an electron beam microanalyzer (EPMA) is shown.
FIG. 7 shows that even when tin plating is applied to a plating film having a random thin plate structure, the random thin plate structure is maintained, and from the measurement results of the copper distribution and the tin distribution, It shows that tin is uniformly deposited (supported).

This experimental result shows that by plating further on the plating film with the random thin plate structure, other metals can be combined with the original plating film with the random thin plate structure. Since it can be uniformly combined with a thin plate structure plating film, the strength of the rough surface structure plating film itself can be adjusted by selecting and using the metal to be combined, and the rough surface structure plating can be performed. This means that the thermal expansion coefficient of the film can be adjusted.
It is possible to adjust the strength of the plating film with the rough surface structure and the coefficient of thermal expansion by joining the base metal and the resin material through the plating film with the rough surface structure. This is effective in that the joint strength of the joined body can be improved, the thermal stress acting on the joined body can be relieved as the environmental temperature changes, and the durability of the joined body can be improved.

(Bonded metal and resin material)
In FIG. 8, a plating film having a random thin plate structure is provided as a rough surface plating film on the surface of a metal as a base material, and the metal 10 and the resin material 20 are integrated through a plating film 16 having a random thin plate structure. An example in which a joined body is formed is shown.

FIG. 8A shows a state in which a plating film 16 having a random thin plate structure is provided, and FIG. 8B shows a state in which the metal 10 and the resin material 20 are integrated by insert molding.
FIG. 8 (a) illustrates a state in which a plating film 16 having a random thin plate structure is formed on the surface of the metal 10, and the plating film 16 having a random thin plate structure is a three-dimensional structure having an extremely complicated form. It is formed. Therefore, when the metal 10 and the resin material 20 are integrally bonded through the plating film 16 having the random thin plate structure, the resin 22 constituting the resin material 20 is formed in the gap portion formed in the plating film 16 having the random thin plate structure. The metal 10 and the resin material 20 are firmly bonded to each other by being filled and bonded to the plating film 16 having a random thin plate structure through a very large contact area, and by an anchor action by the plating film 16 having a random thin plate structure. Connected.
When a plating film with a random thin plate structure in which the above-mentioned carbon nanotubes are incorporated in the plating film as the plating film with a rough surface structure, the bonding strength between the metal and the resin material is increased by the action of the carbon nanotubes incorporated in the plating film. Further improvement is possible.

  When the effect of thermal stress caused by the difference in thermal expansion coefficient between the metal 10 and the resin material 20 when the metal 10 and the resin material 20 are integrated, the plating film 16 having a random thin plate structure is a thin plate. Since the plated metal is configured as a structure with a space inside while intersecting each other, the metal of the base material is integrated with the resin material by etching or the like to form an unevenness on the surface of the metal It is considered that the function to relieve the thermal stress acts more effectively than the one.

In addition, when a plating film having a random thin plate structure in which carbon nanotubes are incorporated in the plating film is used, if the thermal expansion coefficient of the carbon nanotube is smaller than both the metal and the resin material, the plating film of the random thin plate structure is used. The thermal expansion coefficient can be effectively set to an intermediate thermal expansion coefficient between the metal and the resin material, thereby suppressing the action of the thermal stress acting between the metal and the resin material.
In addition, when the plating film with a rough surface structure is configured to plate another metal on the plating film with a random thin plate structure, the thermal expansion coefficient as a whole of the plating film with the random thin plate structure is intermediate between the metal and the resin material. By selecting another metal so as to have a thermal expansion coefficient, it is possible to relieve the thermal stress generated between the metal and the resin material, and to improve the durability of the joined body.

(Joint strength evaluation test: 1)
Cold rolled steel (SPCC) is used as the base metal, PPS (polyphenylene sulfide resin: 40% glass fiber) is used as the resin material to be joined to the base metal, and the tensile shear bond strength of rigid adherends Test (Evaluation test of joint strength of metal / resin material was conducted according to JIS K6850. The shape and dimensions of the sample used in the evaluation test are shown in FIG.
The following three types of samples were used for the evaluation test.
Sample A:
Metal (SPCC) that has not been subjected to any treatment and is formed by integrally molding metal and resin material (PPS) Sample B:
Sample of carbon (SPCC) with a nickel composite plating film of carbon nanotubes as a rough surface plating film and molded integrally with resin material (PPS) Sample C:
The metal (SPCC) surface is plated with nickel as the underlying plating, and the nickel plating film is provided with a plating film with a random thin plate structure as a plating film with a rough surface structure, and integrally molded with a resin material (PPS)

(Sample preparation method)
The plating film of Sample B was formed under the following plating conditions.
a) Roughened plating film Plating bath composition
NiSO ₄ · 6H ₂ O: 1 M
NiCl ₂ · 6H ₂ O: 0.2 M
C ₆ H ₅ Na ₃ O ₇ : 0.08 M
Polyacrylic acid (average molecular weight 5000): 2 × 10 ^-5 M
Carbon nanotubes: 2.0 g L ⁻¹ , 1.0 g L ⁻¹ , 0.5 g L ⁻¹
Electrodeposition Conditions Current Regulation Law Substrate: SPCC
Temperature: Room temperature Current density: 0.5 A dm ^-2
Energization amount: 2928.3 C dm ^-2
Multi-walled carbon nanotubes VGCF (registered trademark) were used as carbon nanotubes, and three types of samples with different amounts of carbon nanotubes were prepared.

The plating film of Sample C was formed under the following plating conditions.
b) Underlying nickel plating film Plating bath composition
NiSO ₄ · 6H ₂ O: 1 M
NiCl ₂ · 6H ₂ O: 0.2 M
H ₃ BO ₄ : 0.5M
Electrodeposition conditions Cathode: SPCC
Anode: Nickel plate Plating area: 10cm ²
Current density: 10mA cm ^-2
Current flow: 1.46 C cm ^-2
Plating temperature: 25 ° C Liquid volume: 100 mL Stirring: None c) Roughened plating film Plating bath composition
CuSO ₄ · 6H ₂ O: 0.85 M
H ₂ SO ₄ : 0.55 M
Polyacrylic acid (average molecular weight 5000): 1 × 10 ^-5 M, 5 × 10 ^-5 M
Electrodeposition conditions Cathode: SPCC
Anode: Pure copper plate Plating area: 10 cm ²
Current density: 5 mA cm ^-2 , 10 mA cm ^-2
Energization amount: 2.7 C cm ^-2
Plating temperature: 25 ° C Liquid volume: 100 mL Stirring: None

As a result of performing an evaluation test on the above samples A, B, and C, as for sample B, the shear strength of the sample having the carbon nanotube addition amount of 1.0 g L ⁻¹ was maximized, and the maximum shear strength of 9.64 MPa was obtained. For sample C, the shear strength of the sample with a polyacrylic acid concentration of 5 × 10 ⁻⁵ and a current density of 5 mA cm ⁻² was maximized, and a maximum shear strength of 3.82 MPa was obtained.
As for sample A, after insert molding, when the sample was taken out from the apparatus, the resin material was peeled off from the metal of the base material, and the shear strength could not be measured.
The above evaluation test results show that the method of providing a composite plating film of carbon nanotubes and the method of providing a plating film of a random thin plate structure are effective as a roughened plating film on the metal surface of the base material. It is.

(Joint strength evaluation test: 2)
In order to evaluate the bonding strength of the metal / resin bonded body, a test piece shown in FIG. 9 was prepared and a tensile shear test was performed. A nickel-carbon nanotube composite plating film was formed as a rough plating film provided on the surface of the substrate. The composite plating film of carbon nanotubes was applied to one end in the longitudinal direction of the base material in a range of 12.5 mm × 25 mm in length and width, and aligned with the range where the composite plating was performed, and then resin-molded. The dimensions of the resin body molded into a flat plate shape are 2.0mm in thickness, 100mm in length, 25mm in width, injection molding conditions are molding temperature 300 ° C, mold temperature 150-160 ° C, injection pressure 121MPa, injection time 1.08s. It is. The resin used for injection molding is PPS (polyphenylene sulfide resin; glass fiber 40%).

The plating conditions of the nickel-carbon nanotube composite plating applied to the surface of the substrate (SPPC) are shown below.
Plating bath composition
NiSO ₄ · 6H ₂ O: 1 M
NiCl ₂ · 6H ₂ O: 0.2 M
C ₆ H ₅ Na ₃ O ₇ : 0.08 M
Polyacrylic acid: 2 × 10 ^-5 M
CNT: 0, 0.25, 0.50, 1.0, 2.0 (gL ^-1 )
Electrodeposition conditions Substrate: Cold rolled steel plate (SPPC)
Anode: Ni
Current density: 1.0 A dm ^-1
Energization amount: 2928 C dm ^-1
Bath temperature: room temperature Stirring: air stirring Carbon nanotubes used for plating are multi-walled carbon nanotubes (VGCF: registered trade name Showa Denko, diameter 150 nm, length 10-20 μm).

FIG. 10 shows the plating surface applied to the substrate surface when no carbon nanotubes are added (FIG. 10 (a)) and when carbon nanotubes are added (1.0 gL ⁻¹ ) (FIG. 10 (b)). A measurement example of the surface SEM image and the surface roughness of the plated surface is shown.
The sample with only nickel plating had a glossy surface, a smooth surface, and a surface roughness of 0.72 μm (RMS). On the other hand, the surface of the sample subjected to the composite plating of carbon nanotubes was found to be uneven from the SEM image, and the surface roughness was 6.03 μm (RMS), which is a surface roughness compared to the case of only nickel plating. The degree became about 10 times.

FIG. 11 shows SEM images of the surface of the plating film when the amount of carbon nanotube added is 0.25 gL ⁻¹ , 0.5 gL ⁻¹ , 1.0 gL ⁻¹ , and 2.0 gL ⁻¹ . In addition, the measurement result of the surface roughness of each sample is shown in the figure (RMS). If the amount of carbon nanotubes added is small (0.25 gL ^-1 , 0.5 gL ^-1 ), the surface of the substrate is partially exposed in the plating film (the part that appears black), and the amount of carbon nanotubes added increases (1.0 gL ⁻¹ , 2.0 gL ⁻¹ ), almost the entire surface of the base material is covered with the plating film. Thus, the form in which the plating film covers the substrate surface affects the surface roughness.

FIG. 12 shows the result of producing a test piece of the joined body shown in FIG. 9 using a metal plate (base material) subjected to composite plating of carbon nanotubes and conducting a tensile shear test. In the tensile shear test, the other end of the metal plate and the other end of the resin body sandwiching the joint part of the test piece are fixedly supported on the chuck of the tensile tester, pulled in the opposite direction in the longitudinal direction, and the value at break is broken Strength.
FIG. 12 shows the test results for those plated with nickel and those plated with nickel-carbon nanotube composite (CNT: 1.0 gL ⁻¹ ). In the case where only nickel plating was applied, the metal of the base material and the resin body were peeled off only by taking out from the injection molding machine, and could not be detected as the breaking strength. On the other hand, the breaking strength of the sample (sample number n = 6) subjected to the nickel-carbon nanotube composite plating was about 7.5 MPa.

Table 1, 0.25gL ^-1 The amount of carbon nanotubes, 0.5gL ^-1, 1.0gL ^-1, nickel was 2.0gL ^-1 - for conjugate produced using the substrate subjected to carbon nanotube composite plating The result of having performed the tensile shear test is shown.

FIG. 13 is a graph showing the test results shown in Table 1.
FIG. 13 (a) shows the breaking strength with the horizontal axis as the added amount of carbon nanotubes, and the breaking strength tends to decrease when the added amount of carbon nanotubes is increased. The breaking strength was the highest among the four types of samples when the amount of carbon nanotube added was 0.25 gL- ¹ . At this time, some of the plurality of samples used in the test resulted in the resin body itself breaking rather than the joint, and it was confirmed that the joining force was extremely strong.
FIG. 13 (b) shows a fractured narrow path with the horizontal axis as the surface roughness, so that the surface roughness increases and the breaking strength does not always increase, and there is a surface roughness that provides the maximum breaking strength. It is estimated that

FIG. 14 is an SEM image of the joint surface before and after the joined body sample is broken. Fig. 14 (a) is the plated surface before the test, Fig. 14 (b) is the SEM image of the surface of the joint portion on the base material side (metal side) after the test (after fracture), and Fig. 14 (c) is the test surface after the test. It is a SEM image of the surface of the junction part by the side of a resin body (resin molded object).
FIG. 14 (b) shows that the form of plating does not change significantly on the plating surface on the base material side, and that the carbon nanotubes are removed. FIG. 14 (c) shows that the resin body is partially broken at the time of breakage, and that carbon nanotubes are taken into the resin body side. That is, when the base material and the resin are integrated by injection molding (resin molding), the resin enters the unevenness of the plating surface, and the carbon nanotubes enter (intrude) the unevenness of the plating film into the resin body. Suggest that they are connected.

FIG. 15 is an SEM image showing the enlarged form of the joint of the test piece. 15 (a), (b) and (c) are similar to FIGS. 14 (a), (b) and (c), the plated surface before and after the test of the bonded body, the bonded surface on the substrate side, and the resin body side. The state of the joint surface is shown.
From FIG. 15, it can be seen that the carbon nanotubes are removed from the plated surface of the base material after the fracture, and that the carbon nanotubes removed from the plated surface are taken into the resin body side.

FIG. 16 shows a cross-sectional SEM image (FIG. 16 (a)) of the interface of the joint, observed to see the state of the interface between the plating film and the resin when the base material and the resin are integrally molded, An EDS mapping image (FIG. 16B) is shown. From the cross-sectional SEM image, it can be seen that irregularities with complex shapes are formed by plating on the surface of the base material, and that the resin is filled following the irregularities.
However, when the EDS measurement result shown in FIG. 16 (b) is observed in detail, the resin is not completely filled in the deep portion of the unevenness of the plating film and remains as a void. This void portion results in that the carbon nanotubes peeled off from the plating metal are sent together with the resin when the resin flows in, thereby inhibiting the filling of the resin, and the void remains.

  The method of integrating metal and resin using composite plating of carbon nanotubes is that the plating film is formed on a complex uneven surface, and the resin enters and fills the inside of the unevenness. An extremely large anchoring effect acts between the substrate and the resin, and the carbon nanotubes contained in the plating film act as a bridge connecting the plating film (substrate) and the resin. By further improving the connectivity (joinability), it becomes possible to obtain a very large joining force.

  When the base material and the resin are integrated by injection molding, the problem that the unfilled portion of the resin remains on the unevenness of the plating film due to the carbon nanotubes contained in the composite plating of carbon nanotubes flowing together with the resin is After carbon nanotube composite plating is applied to the material, the substrate is treated by ultrasonic treatment or the like to remove carbon nanotubes that are easily peeled off from the carbon nanotube composite plating film in advance, and then an integral resin of the substrate and resin What is necessary is just to form the joined body of a metal and resin by shaping | molding.

(Joint strength evaluation test: 3)
As a test piece to be used for the tensile shear test, a base material provided with a plating film having a random thin plate structure by copper plating is prepared as a rough surface structure plating film to be applied to the surface of the base material. The base material and the PPS resin were integrally molded to prepare a test piece having the same shape as the test piece shown in FIG. 9, and a tensile shear test was performed.

  In order to improve the adhesion between the base material and the plating film with the rough surface structure, the surface of the base material is first subjected to a copper strike plating, and then the surface of the strike plating is provided with a random thin plate structure copper plating film with a rough surface structure. Formed. Strike plating is a plating with extremely good adhesion to the base material. By using strike plating as the base plating for copper plating with a random thin plate structure, the adhesion between the base material and the copper plating film with a random thin plate structure is effective. Can be improved.

The copper strike plating conditions of the sample created in this test are shown below.
Plating bath composition
Cu ₂ P ₂ O ₇ : 14 gL ^-1
K ₄ P ₂ O ₇ : 120 gL ^-1
Electrodeposition conditions Substrate: Cold rolled steel plate (SPPC)
Anode: Pure copper plate Current density: 10 mA cm ^-2
Current flow: 1.36 Ccm ^-2
Bath temperature: Room temperature Plating area: 4 × 2.5 cm ²
Stirring: Air stirring

Next, copper plating with a random thin plate structure was applied to the substrate subjected to the copper strike plating. The plating conditions are shown below.
Plating bath composition
CuSO ₄ · 6H ₂ O: 0.85 M
H ₂ SO ₄ : 0.55 M
Polyacrylic acid (average molecular weight 5000): 0, 5 × 10 ⁻⁵ M, 1 × 10 ⁻⁴ M, 2 × 10 ⁻⁴ M
Electrodeposition conditions Substrate: Cold rolled steel plate (SPPC)
Anode: Pure copper plate Current density: 5 mA cm ^-2
Energization amount: 2.7 Ccm ^-2
Plating temperature: Room temperature Plating area: 4 × 2.5 cm ²
Stirring: None

  FIG. 17 shows an SEM image of the surface of the plating film having a rough surface structure applied to the substrate under the above plating conditions, and the surface roughness of the plating film. As the amount of polyacrylic acid added is increased, the form of the copper thin plate constituting the plating film becomes more prominent, and the thin plate becomes thinner and grows. Along with this, the surface roughness of the plating film increases. On the other hand, when the amount of polyacrylic acid added is small, the plating film has a grainy uneven surface.

FIG. 18 shows the result of a tensile shear test using a test piece. The horizontal axis represents the degree of surface thickness of the plating film, and the vertical axis represents the breaking strength. The test results shown in FIG. 18 indicate that the fracture strength of the sample with a large surface roughness of the plating film is not necessarily high, but rather the fracture strength of the sample with a low surface roughness is high. In the tested sample, the maximum average breaking strength was 4.2 MPa.
In addition, about the sample which has not formed the plating film of the rough surface structure, when the sample was taken out from the injection molding machine, the molded body of resin peeled from the base material, and the breaking strength could not be measured.

FIG. 19 is a cross-sectional SEM image in which the interface between the substrate and the resin is observed in order to examine the state of the interface between the plating film and the resin when the substrate and the resin are integrally formed by injection molding. In the figure, the sample with a polyacrylic acid concentration of 5 × 10 ⁻⁵ M has a granular plating film, and the structure of the granular plating film is maintained even after injection molding. In contrast, in the sample having a polyacrylic acid concentration of 1 × 10 ⁻⁴ M, it can be seen that the thin plate of the plating film is deformed by the pressure of the resin during the injection molding. Furthermore, in the sample having a polyacrylic acid concentration of 2 × 10 ⁻⁴ M, the plating film is broken and separated by the resin pressure at the time of injection molding.

From this observation result, when the polyacrylic acid concentration is higher than the concentration at which the thin plate-like form of the plating film clearly appears, the thin plate of the plating film is deformed or the plating film is broken by the resin pressure during resin molding, and the base material and the resin It is presumed that the bonding strength with the body is reduced. The reason for the extremely low bonding strength in the sample with a polyacrylic acid concentration of 2 × 10 ^-4 M is that the plating film was broken during injection molding, and the effect of bonding the substrate and the resin body through the plating film was lost. Because it was broken.

  FIG. 20 shows the result of the EDS analysis of sulfur in the vicinity of the interface between the plating film and the resin in order to examine the state in which the resin has entered the inside of the plating film when the base material and the resin are injection molded. . The measurement results shown in FIG. 20 show that when the polyacrylic acid concentration is low, that is, when the plating film is formed in a granular form, the resin enters and fills the deep part of the plating film, When the polyacrylic acid concentration is increased, the resin is not completely filled in the thickness direction of the plating film, and the resin remains only in the vicinity of the surface of the plating film, indicating that the resin has not entered deeper.

  The reason why the resin penetration degree is different is that when the plating film is formed in a granular shape, a space where the resin easily enters is formed, whereas the thin plate shape of the plating film becomes prominent. This is considered to be due to the fact that the shape of the gap is random and complicated, so that the entry of the resin is hindered, and that the gap into which the resin enters is further narrowed by the pressure at which the resin enters and the thin plate is collapsed. It is considered that the difference in the degree of penetration of the resin into the plating film caused the magnitude of the anchoring action by the plating film, and the difference in the breaking strength described above.

FIGS. 21 and 22 show SEM images obtained by observing the bonding surface on the base material side and the resin body side in order to observe the state of the fracture surface generated by the tensile shear test. FIG. 21 shows the state of the plating film on the base material before and after the tensile shear test, and FIG. 22 shows the surface of the joint surface of the resin body after fracture.
Referring to FIG. 21, for the sample having a polyacrylic acid concentration of 5 × 10 ⁻⁵ M, the plated film after the fracture maintains the same granular form as before the test. On the other hand, on the fracture surface after the test of the sample having a polyacrylic acid concentration of 1 × 10 ⁻⁴ M, the plating film is partially damaged, and the thin plate-like plating film is lacking. Further, on the fracture surface of the sample having a polyacrylic acid concentration of 2 × 10 ⁻⁴ M, most of the plating film formed in a thin plate shape is broken, and the original shape of the plating film is lost.

Looking at the fracture surface on the resin body side shown in FIG. 22, for the sample with a polyacrylic acid concentration of 5 × 10 ⁻⁵ M, the resin is stretched in the shear direction and the PPS resin itself is broken. In the sample having a polyacrylic acid concentration of 1 × 10 ⁻⁴ M, the plating film is partially transferred to the fracture surface of the resin body. In addition, in the sample having a polyacrylic acid concentration of 2 × 10 ⁻⁴ M, the plating film is almost transferred to the resin body side, and a thin plate structure of the plating film is seen on the resin body side.

  The observation results shown in FIGS. 21 and 22 show that when a plating film having a grainy rough surface structure is formed on the substrate as a plating film having a random thin plate structure, the fracture occurs at the interface between the plating film and the resin, resulting in extremely high breaking strength. On the other hand, if a plating film with a thin plate structure is prominently formed as a plating film with a random thin plate structure, the plating film itself (thin plate) is weak, so the plating film itself breaks and the material itself (strength of the resin body) It is shown that a large breaking strength such that the breaking strength depends on the strength of) cannot be obtained.

(Joint strength evaluation test: 4)
Prepare a base material provided with a plating film with a random thin plate structure by copper plating as a rough surface plating film to be applied to the surface of the base material, and integrally form the base material and PPS resin by injection molding as in the above example. A test piece similar to the test piece described above was prepared and a tensile shear test was performed.

Copper strike plating was first applied to the surface of the substrate, and then roughening plating was applied. The plating conditions for strike plating and roughening plating are shown below.
Strike plating Plating bath composition
Cu ₂ P ₂ O ₇ : 0.042M
K ₄ P ₂ O ₇ : 0.36M
Plating conditions Substrate: Cold rolled steel plate (SPPC)
Anode: Pure copper plate Current density: 10 mA cm ^-2
Current flow: 1.36 Ccm ^-2
Bath temperature: Room temperature Plating area: 4 × 2.5 cm ²
Stirring: Air stirring Roughening plating Plating bath composition
CuSO ₄ · 6H ₂ O: 0.85 M

Table 2 shows the bonding strength test results. The joint strength evaluation test was based on the ISO 19095 tensile shear test. The number of samples is 2, the metal is SPCC (thickness 1.6 mm), and the resin is PPS.
In all samples, a high bonding strength of 35 MPa or more was obtained as an average breaking stress.

  FIG. 23 shows a state where a sample after insert molding is placed on a hot plate heated to 300 ° C. and a test for separating the base material (metal) and the resin molded part is performed. FIG. 23 (a) shows a state immediately after placing the sample on the hot plate, and FIG. 23 (b) shows a state in which the resin molded part is lifted with tweezers 12 seconds after the sample is started to be heated with the hot plate. The resin molded part was easily separated from the substrate by lifting the resin molded part with tweezers.

FIG. 24 and FIG. 25 show the surface states of the joint portion on the base material side (metal side) and the resin molding portion side after the sample is heated to separate the resin molding portion from the base material.
FIG. 24 (a) is an appearance photograph of the base material after separation, and a broken line range shows a portion where a metal and a resin are joined. FIG. 24B is a surface SEM image of the joint portion. From the surface SEM image, it can be seen that the surface of the base material after separation has a random uneven shape, and the resin remains on the plated surface.
FIG. 25 (a) is a photograph of the appearance of the resin molded part after separation, and the broken line indicates the part bonded to the base material. FIG. 25B is a surface SEM image of the bonded portion. It can be seen that the joint surface of the resin molded portion is an uneven surface, and the resin has melted and the resin has entered the rough surface of the plating film to be molded.

(Joint strength evaluation test: 5)
As a rough surface plating film to be applied to the surface of the base material, a composite plating film of carbon nanotubes is provided, and the base material and the PPS resin are integrally formed by injection molding, and a test piece similar to the above-described test piece is produced, A tensile shear test was performed.
The plating conditions for composite plating of carbon nanotubes are shown below.
Plating bath composition
NiSO ₄・ 6H ₂ O ： 1M
NiCl ₂ · 6H ₂ O: 0.2M
_{C 6 H 5 Na 3 O 7} : 0.08M
Polyacrylic acid: 2 × 10 ^-5 M
CNT: 2.0gL ^-4
Multiwall carbon nanotubes (manufactured by Showa Denko: diameter 150 nm, length 10-20 μm) were used as CNTs.
Plating conditions Substrate: Cold rolled steel plate (SPPC)
Anode: Ni
Current density: 1.0A dm ^-2
Energization amount: 2928C dm ^-2
Bath temperature: Room temperature Stirring: Air stirring

FIG. 26 is a surface SEM image of the nickel-carbon nanotube composite plating film provided on the surface of the substrate. It can be seen that carbon nanotubes are taken into the nickel plating film and nickel particles are connected by the carbon nanotubes.
A test piece in which a PPS resin was integrally formed on an SPPC substrate plated with nickel-carbon nanotube composite plating by the above method was manufactured, and an ISO 19095 tensile shear test was conducted in the same manner as described above. The measurement result of MPa was obtained.

FIG. 27 shows the state of the test in which the test piece after integral molding was heated with a hot plate heated to 300 ° C. to separate the base material and the resin molded part. Also in this experiment, the resin molded part and the substrate were separated by heating at 300 ° C. for 12 seconds and pulling up the resin molded part with tweezers.
FIG. 28 and FIG. 29 show the results of observing the surface state of the joint between the base material and the resin molded part after heating the sample and separating the resin molded part from the base material.
FIG. 28 (b) is a surface SEM image of a portion of the base material surface that has been subjected to nickel-carbon nanotube composite plating. The plating film in which the carbon nanotubes are incorporated remains on the base material side, and the resin is partially applied to the plating film. You can see how it remains.
FIG. 29B is a surface SEM image of the joint surface of the resin molded portion. The surface of the resin being wavy indicates that the resin has melted and flowed. Moreover, it can be seen that an uneven surface is seen on the joint surface and that the composite plating film is not attached to the resin molded portion side.

DESCRIPTION OF SYMBOLS 10 Metal 12 Composite plating film of carbon nanotube 14 Carbon nanotube 16 Plating film of random thin plate structure 20 Resin material 21 Carbon fiber 22 Resin

Claims (10)

On the surface of the metal, a plating film having a rough structure is provided,
A metal / resin material joined body, wherein the metal and the resin material are integrally joined via the rough surface plating film.   2. The metal / resin material assembly according to claim 1, wherein a base plating film is provided on the surface of the metal, and the plating film having the rough surface structure is provided on the base plating film.   3. The joined body of metal and resin material according to claim 2, wherein the base plating film is a strike plating film.   The metal-resin-bonded body according to any one of claims 1 to 3, wherein a composite plating film of carbon nanotubes is provided as the plating film having the rough surface structure.   The metal-resin-bonded body according to any one of claims 1 to 3, wherein a plating film having a random thin plate structure is provided as the plating film having the rough surface structure.   6. The metal / resin material joined body according to claim 5, wherein the random thin plate structure plating film is a random thin plate structure plating film in which carbon nanotubes are incorporated into the plating film.   The metal and resin material according to claim 5 or 6, wherein the plating film of the random thin plate structure is further plated with a metal different from the plating metal constituting the plating film of the random thin plate structure. Joined body.   The metal-resin-bonded body according to any one of claims 5 to 7, wherein the random thin plate structure plating film is configured as a plating film having a granular rough surface structure.   The joined body of a metal and a resin material according to any one of claims 5 to 8, wherein the plating film having the random thin plate structure is made of copper. The said resin material is a carbon fiber reinforced plastic, The joined body of the metal and resin material as described in any one of Claims 1-9 characterized by the above-mentioned.