Highly conductive tin-graphene composite plating for automotive terminals and electronic components

Abstract

To provide a metallic component (such as a terminal and an electronic contact) being low cost and realizing the improvement of high conductivity, wear resistance and heat resistance as a component (such as an onboard terminal and an electric contact) of a charging device corresponding to a wire harness and an EV / a PHV.SOLUTION: An Sn-graphene composite plating film component comprises: a base material for electric connection (or electric conduction); and a Sn graphene composite plating film plated on the surface of the base material. The size of graphene is 0.01 to 6 μm and the content of the graphene is 0.5 to 30 at%.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a highly conductive tin-graphene composite plating for in-vehicle terminals and electronic components.

Background Art

[0002] Conventionally, about 90% of the terminal materials for wire harnesses, which are in-vehicle electrical components, are Sn plating materials in which a tin (Sn) film is coated on the surface of a copper alloy, and about 10% are noble metal plating materials such as gold (Au) and palladium (Pd). Moreover, against the backdrop of considerations for the global environment, the switch from fossil fuel vehicles to EV / PHV that do not emit CO2 is accelerating, and further, from the perspective of safety, automated driving is also progressing, and the requirements regarding the conductivity of terminal and connector materials are becoming increasingly high. Currently, from the aspect of improving conductivity, as a terminal electrode material, the use of a noble metal pure silver (Ag) plating material, which has the highest conductivity among all metals, is being promoted. However, it is realistically impossible in terms of cost and resources to make all terminal materials Ag plating, which is a noble metal. On the other hand, graphene is known to have a theoretical conductivity higher than that of silver and excellent lubricity and thermal stability. However, since graphene cannot be used alone, it has to be compounded with other materials. Also, ordinary commercially available graphene powder is mostly mainly graphene oxide and is difficult to disperse in an aqueous solution, so it is difficult to be practical in terms of work and manufacturing costs. Also, Sn-based plating has conventionally been used as a soldering material and a solder material for electronic components. From the perspective of power consumption, improvement in the conductivity of Sn-based plating materials is required.

[0003] The current Sn plating material used as a general terminal has low cost, excellent solder wetting properties and workability. However, since the melting point of Sn metal is low and it is extremely soft (20 - 30 Hv), there are problems such as low heat resistance and low wear resistance. And in order to improve the wear resistance, research on the compounding with non-metallic materials such as graphite powder, molybdenum disulfide, and Teflon (registered trademark) particles, which are solid lubricants, has been reported. However, in all cases, the effect of improving the wear resistance is low, and in addition, it has caused a decrease in conductivity.

[0004] Patent Document 1 describes a method for producing a coating containing carbon nanotubes, fullerenes, and / or graphene on a substrate, but it does not describe the specific structure of graphene containing tin. In Patent Document 2, the present inventors disclosed a Sn-graphene composite plating with significantly improved wear resistance using hybrid plating technology, but there was room for improvement in conductivity. In particular, the correlation between graphene size and the properties of the plating film, as well as the contact resistance stability during wear and in high-temperature environments, were not described. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2012-506357 [Patent Document 2] Patent application No. 2020-020764 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] The aforementioned plating materials have problems in that they are insufficient for improving the performance and durability of wire harnesses to meet the demands of increasingly sophisticated electronic control systems in automobiles, and for improving the performance and durability of connection components (e.g., on-board terminals, electrical contacts, etc.) for various electronic devices to meet the demands of the further expansion of EVs / PHVs. Therefore, the present invention aims to provide metal components (e.g., on-board terminals, electrical contacts, etc.) that are low-cost and achieve improved conductivity, wear resistance, and other properties. [Means for solving the problem]

[0007] The present invention, which solves the above problems, is as follows. (1) A Sn-graphene composite plated film component comprising a substrate for electrical connection (or current conduction) and a Sn-graphene composite plated film plated on the surface of the substrate, wherein the graphene size (hereinafter sometimes referred to as "graphene size") is 0.01 to 6 μm and the graphene content (hereinafter sometimes referred to as "graphene content") is 0.5 to 30 at%. The term "Sn-graphene composite plating film plated on the surface of a substrate" includes a state in which the Sn-graphene composite plating film has plated (coated) at least a portion of the surface of the substrate. Examples of base materials include metal terminal materials, and examples of Sn-graphene composite plated film components include Sn-graphene composite plated film metal terminals and electrical contacts. Furthermore, the remainder of the Sn-graphene composite plating film, other than graphene, consists of Sn and unavoidable impurities. (2) The Sn-graphene composite plated film component according to (1), characterized in that the electrical contact resistance of the Sn-graphene composite plated film is 0.8 mΩ or less. (3) The Sn-graphene composite plated film component according to (1) or (2), characterized in that the Vickers hardness of the composite plated film is 40 Hv or higher. (4) A Sn-graphene composite plated film component according to any one of (1) to (3), characterized in that the base material includes copper or a copper alloy. The reason why copper or copper alloys are preferred as the substrate material for the Sn-graphene plating film is that copper and copper alloys have high conductivity and high strength, and specific examples of substrate materials, such as metal terminal materials, are widely used as electrical connection materials for automotive terminals and electronic components. Alternatively, any conductive metal material such as aluminum alloy or steel may be used. Furthermore, in the case of electronic equipment mounted in vehicles, copper foil, aluminum foil, or organic films with a copper or aluminum film deposited on them may also be used. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide metal parts (such as in-vehicle terminals, electrical contacts) that achieve low cost, high conductivity, wear resistance, and heat resistance in accordance with the improvement of performance and durability of wire harnesses with enhanced performance and durability and the improvement of performance and durability of parts (such as terminals, contacts) of electrical connection devices corresponding to EV / PHVs.

Brief Description of the Drawings

[0009] [Figure 1] It is a diagram showing a cross-sectional view of a Sn-graphene composite plating film Cu part in which the surface of a Cu substrate is plated with a Sn-graphene composite plating film according to an embodiment of the present invention. [Figure 2] It is a diagram showing the relationship between the graphene (carbon) content and the contact resistance of a Sn-graphene composite plating film with a mixed Sn, Ag, and graphene size (<6 μm). [Figure 3] It is a diagram showing the relationship between the graphene (carbon) content and the contact resistance of a Sn-graphene composite plating film with a Sn, Ag, and graphene size <1 μm. [Figure 4] It is a diagram showing, respectively, (a) the relationship between the graphene (carbon) content and the contact resistance of a Sn-graphene composite plating film with a mixed Sn and graphene size <6 μm, and (b) schematically, the pinning effect of graphene in a Sn-graphene composite plating film where the graphene size > Sn particle size. [Figure 5] It is a diagram showing, respectively, (a) the relationship between the graphene (carbon) content and the contact resistance of a Sn-graphene composite plating film with a Sn and graphene size <1 μm, and (b) schematically, the pinning effect of graphene in a Sn-graphene composite plating film where the graphene size < Sn particle size. [Figure 6] It is a diagram showing, respectively, the relationship between the electrical contact resistance and the wear time of a Sn-graphene composite plating film with (a) a Sn and graphene size <1 μm and (b) a Sn and graphene size of 3 - 5 μm in a wear test. [Figure 7] It is a diagram showing the measurement results of the electrical contact resistance of Sn and Sn-graphene composite plating films before heating and after a heat resistance test at 200°C for 80 hours. [Figure 8] This figure shows an example of a reel-to-reel method for manufacturing Sn-graphene composite plating. [Modes for carrying out the invention]

[0010] The embodiments of the present invention will be described below with reference to the drawings. The present invention is not limited to the following embodiments, and modifications, alterations, and improvements may be made without departing from the scope of the invention.

[0011] As shown in Figure 1, the surface of the Cu component 1 with a Sn-graphene composite plating film 4 is coated with a Sn-graphene composite plating film 4 on the Cu substrate 5. The Sn-graphene composite plating film 4 contains a Sn matrix (Sn layer) 3 and graphene 2 and 2' (hereinafter sometimes simply referred to as "graphene 2") dispersed in the Sn matrix 3. Note that graphene 2 refers to the case where the lattice structure of graphene is approximately flush with the cross-sectional view, and graphene 2' refers to the case where the lattice structure of graphene is approximately perpendicular to the cross-sectional view.

[0012] The size and content of graphene 2 in the Sn-graphene composite plating film 4 are as follows. First, regarding the size (in-plane size) of graphene 2, in order to uniformly disperse it in the plating layer depending on the type of electrical connection product, it should be 6 μm or less, and more preferably 0.01 μm to 5 μm, from the viewpoint of being smaller than the film thickness. For example, in the case of reflow Sn plating for automotive terminals, the film thickness is 2 μm or less, so it is preferable to combine it with graphene that is smaller than that. Also, in the case of plated mounting products, the Sn film thickness is thick, 4-8 μm, so considering dispersibility, it may be 6 μm or less. Next, regarding the content of graphene 2, from the perspective of suppressing adhesion when fitting as the Sn-graphene composite plating film Cu-made component 1 (for example, a terminal), improving wear resistance, and maintaining the conductivity of the plating film, it is 0.5 to 30 at%, and more preferably 5 to 25 at%. If it is less than 0.5 at%, the effect of improving conductivity is insufficient, and if it is more than 30 at%, the strength between graphene layers is weak and the conductivity is low, so there is a risk that the strength and conductivity of the plating film will decrease instead.

[0013] As the base material for electrical connection (or for conducting electricity), in addition to Cu, aluminum alloys, iron-nickel alloys (for example, 42 alloy), SUS materials, etc. can be used, but from the perspective of the conductivity of the entire terminal, Cu (copper) or Cu (copper) alloy is preferred. Also, organic materials with copper foil, aluminum foil, or copper film or aluminum film deposited on them may be used. Also, as the form (shape) of graphene, graphene exists in a sheet form by stacking several to dozens of graphene sheets. For the production of the Sn-graphene composite plating film, a hybrid plating method combining the electroplating of Sn and the electrophoretic deposition of graphene sheets can be used.

Examples

[0014] (Production of Sn-graphene composite plating film) A Cu alloy plate (20×50×0.2 mm) was used as the base material (metal terminal material), and alkaline electrolytic degreasing and pickling were performed as pretreatment. For the hybrid plating, a sulfuric acid-based bright Sn plating bath was used as the basic solution, and a plating solution with 15 ml / L of the electrolytically exfoliated graphene dispersion added was used to produce a Sn-graphene composite plating film by the hybrid electroplating method. That is, the hybrid plating includes the process of electrophoretic deposition of graphene nanosheets of various sizes contained in the graphene dispersion and the process of electroplating the metal terminal material with Sn. As elements of the electroplating conditions with Sn, current density, bath solution temperature, stirring method, plating time, etc. were considered. Also, for comparison, the film thickness was adjusted to 5 μm according to the plating time.

[0015] As a pretreatment for the Cu alloy substrate, alkaline electrolytic degreasing and acid pickling were performed, but the treatment conditions were not specifically defined. On the other hand, electrolytic stripping was carried out as follows: Graphite was immersed in an aqueous solution, and the graphite was decomposed into layers by the action of a strong electric field and electrochemical reaction to produce layered graphene nanosheets. The electrolytically stripped graphene was approximately 6 μm or less, depending on the crystalline state of the raw material graphite (graphite). To investigate the effect of graphene size, separation was performed by filtration using filters with pore sizes of 5 μm, 3 μm, and 1 μm, respectively. All operations were carried out in an aqueous solution, and the obtained graphene became reduced graphene without oxidation.

[0016] Tables 1 and 2 summarize the manufacturing conditions and their respective measurements for the manufactured sample (Sn-graphene composite plated film on a Cu substrate (Example)) and the comparative example sample. Specifically, Table 1 is a list of the conditions and measurement results for Sn-graphene composite plated films manufactured under various conditions as Examples (1-16) of the present invention. On the other hand, Table 2 shows the measurement results, such as contact resistance, for pure Sn plated films without graphene addition, commercially available reflow Sn plating for reference, and precious metal Ag plating as comparative examples (1-5) of the present invention. In Table 1, a graphene size of less than 6 μm means that the graphene is in a mixed state, as it is not filtered after electrolytic exfoliation. A graphene size of 3-5 μm (sometimes referred to as Gr35) means that the pores pass through a 5 μm filter but not a 3 μm filter, a graphene size of 1-3 μm means that the pores pass through a 3 μm filter but not a 1 μm filter, and a graphene size of less than 1 μm (sometimes referred to as Gr01) means that the pores pass through a 1 μm filter. While pure Sn plating yielded glossy, smooth films depending on the additives used, Sn-graphene composite plating yielded films ranging from glossy to semi-glossy depending on the plating conditions.

[0017] [Table 1] In Table 1, a stirring method of "uniaxial" means that the graphene dispersion (plating solution) flows in a direction approximately perpendicular to the plating surface of the substrate, while a stirring method of "torsion" means that the graphene dispersion (plating solution) convects in a direction approximately horizontal to the plating surface. Furthermore, the carbon content (at%) for Examples 6-9 and Examples 13, 15, and 16 is as follows. Based on the plating film preparation conditions, it is estimated that Example 6 is approximately 11 at%, Examples 7-9 are 15-20 at%, and Examples 13, 15, and 16 are 9-11 at%. [Table 2]

[0018] From Tables 1 and 2 and Figure 2, the following can be seen: When the graphene size < 6 μm, the electrical contact resistance (contact resistance) was as follows: Graphene content (Carbon content) 10.6 at% (Example 1) / pure Sn plating film (Comparative Example 1) = 0.63 / 0.93 = 0.68; Graphene content 14.7 at% (Example 2) / pure Sn plating film (Comparative Example 1) = 2.63 / 0.93 = 2.83; Graphene content 10.6 at% (Example 1) / pure Ag plating film (Comparative Example 4) = 0.63 / 0.61 = 1.03; Graphene content 14.7 at% (Example 2) / pure Sn plating film (Comparative Example 1) = 2.63 / 0.93 = 2.83. Furthermore, since the electrical contact resistance (contact resistance) of Comparative Examples 2 and 3 was about the same as that of Comparative Example 1, the above descriptions of Examples 1 and 2 for Comparative Example 1 are also substantially equivalent for Comparative Examples 2 and 3. Furthermore, among Examples 7 to 9, Example 7 had the smallest electrical contact resistance (contact resistance). Regarding electrical contact resistance (contact resistance), for example, comparing Example 7 to Example 3, Example 7 / Example 3 = 0.61 / 0.73 = 0.84, and comparing it to Example 3, Example 7 / Example 6 = 0.61 / 0.61 = 1.0.

[0019] Regarding electrical contact resistance (contact resistance), when the graphene size was <6 μm, the electrical contact resistance of the graphene content 10.6 at% (Example 1) was equivalent to that of the pure Ag plating film (Comparative Example 4). On the other hand, with a graphene content of 14.7 at% (Example 2), although it was about three times that of the pure Sn plating film (Comparative Example 1), the microhardness, as described later, was higher than that of the pure Sn plating film (Comparative Example 1). Therefore, from the viewpoint of hardness, Example 2 is superior to the pure Sn plating film (Comparative Example 1) and can be used depending on the application.

[0020] (Electrical contact resistance measurement) The conditions for measuring electrical contact resistance were as follows: Conditions: Load variation type (0~0.5~0N, with sliding), Contact resistance value (value at a load of 0.5N), Measuring device: Electrical contact resistance measuring instrument (Yamazaki Seiki Electrical Contact Simulator CRS-1 type). The mating terminal was 24K gold wire, and the fixed terminal was 18K gold plated.

[0021] From Tables 1 and 2 and Figure 3, the following can be seen: When graphene size < 1 μm, the electrical contact resistance (contact resistance) is related to the graphene content (carbon The content of the saturates was 17.2 at% (Example 10) / pure Sn plating film (Comparative Example 1) = 0.63 / 0.93 = 0.68, the graphene content was 20.6 at% (Example 11) / pure Sn plating film (Comparative Example 1) = 0.66 / 0.93 = 0.71, the graphene content was 23.2 at% (Example 12) / pure Sn plating film (Comparative Example 1) = 0.65 / 0.93 = 0.70, the graphene content was 17.2 at% (Example 10) / pure Ag plating film (Comparative Example 4) = 0.63 / 0.61 = 1.03, the graphene content was 20.6 at% (Example 11) / pure Ag plating film (Comparative Example 4) = 0.66 / 0.61 = 1.08, and the graphene content was 23.2 at% (Example 12) / pure Ag plating film (Comparative Example 4) = 0.65 / 0.61 = 1.07.

[0022] The contact resistance measurement results in Tables 1 and 2 show that the addition of graphene to the Sn plating layer resulted in lower electrical contact resistance than pure Sn plating, indicating improved conductivity. Furthermore, under the same plating conditions (current density), a smaller graphene size resulted in a greater improvement in conductivity. In addition, it was found that the influence of the stirring method was small when the graphene size was the same (<1 μm). Furthermore, the contact resistance of the Sn-graphene composite plating film was found to be lower than that of commercially available Sn plating, and it was found to have high conductivity equivalent to that of precious metal silver plating.

[0023] Regarding electrical contact resistance (contact resistance), when the graphene size was <1 μm, the electrical contact resistance was equivalent to or similar to that of a pure Ag plating film (Comparative Example 4) when the graphene content was 17.2 at% (Example 10), 20.6 at% (Example 11), and 23.2 at% (Example 12). Furthermore, it was found to be reduced by approximately 30% compared to a pure Sn plating film (Comparative Example 1). Furthermore, since the electrical contact resistance (contact resistance) of Comparative Example 5 was about the same as that of Comparative Example 4, the above descriptions of Examples 10 to 12 for Comparative Example 1 are also almost equivalent for Comparative Example 5.

[0024] From Tables 1 and 2 and Figure 4(a), the following can be seen: When the graphene size was <6 μm, the microhardness (hardness) was 1.38 for a graphene content of 10.6 at% (Example 1) / pure Sn plating film (Comparative Example 1) and 76.7 / 38.9 = 1.97 for a graphene content of 14.7 at% (Example 2) / pure Sn plating film (Comparative Example 1). In other words, the graphene content of 14.7 at% (Example 2) showed a 97% improvement in microhardness (hardness) compared to the pure Sn plating film (Comparative Example 1).

[0025] Furthermore, the following can be seen from Tables 1 and 2 and Figure 5(a): When the graphene size < 1 μm, the microhardness (hardness) was as follows: for a graphene content (carbon content) of 17.2 at% (Example 10) / pure Sn plating film (Comparative Example 1) = 42.3 / 38.9 = 1.09, for a graphene content of 20.6 at% (Example 11) / pure Sn plating film (Comparative Example 1) = 46.0 / 38.9 = 1.18, and for a graphene content of 23.2 at% (Example 12) / pure Sn plating film (Comparative Example 1) = 50.6 / 38.9 = 1.30. In other words, the graphene content of 23.2 at% (Example 12) showed a 30% improvement in microhardness (hardness) compared to the pure Sn plating film (Comparative Example 1).

[0026] (Microhardness measurement) The conditions for measuring microhardness (Vickers hardness) were as follows: Conditions: Load: 490.3 mN, Holding time: 20 sec, Measuring device: Vickers hardness tester (Shimadzu HMV-G31ST)

[0027] As shown in Figures 4(b) and 5(b), the size of the graphene affects the effectiveness of the pinning effect, and it is thought that a larger graphene size (Figure 4(b)) results in a stronger pinning effect and greater hardness than a smaller graphene size (Figure 5(a)). The pinning effect refers to the effect in which a single graphene particle links multiple Sn matrix crystals, thereby hardening the Sn matrix.

[0028] (Abrasion resistance: Measurement of electrical contact resistance in abrasion tests) To evaluate the reliability of electrical connections due to engine vibrations during vehicle operation, the variation in electrical contact resistance during wear testing was measured under the following conditions: Equipment: Yamazaki Seiki Precision Wear and Friction Tester (CRS-G2050). Measurement conditions: Load: 1N, sliding distance: 200μm, frequency: 1Hz. Counter material: Embossed material processed from commercially available bright Sn plated material was used (film thickness 2μm).

[0029] From the examples of Sn-Gr01-1A (Example 13), Sn-Gr01-2A (Example 14), Sn-Gr01-3A (Example 15), and Sn-Gr01-6A (Example 16) shown in Figure 6(a), and the examples of Sn-Gr35-1A (Example 3), Sn-Gr35-2A (Example 4), Sn-Gr01-3A (Example 5), Sn-Gr01-6A (Example 6), and pure Sn plating (Comparative Example 1) shown in Figure 6(b), the following can be seen. Specifically, as shown in Figures 6(a) and (b), in the abrasion test, the contact resistance of the pure Sn plating (Comparative Example 1) increased rapidly due to abrasion, but in all cases, the Sn-graphene composite plating of the present invention showed a delayed increase in contact resistance, confirming that the abrasion resistance of the plating film was superior to that of the pure Sn plating. Furthermore, the stable range of contact resistance was wider for larger graphene sizes (3-5 μm) compared to smaller sizes (less than 1 μm). This result is consistent with the effect on the hardness of the plating film. It was also confirmed that the stability of contact resistance in the abrasion test depended on the manufacturing conditions.

[0030] (Heat resistance evaluation: Stability of electrical contact resistance in high-temperature environments) When terminal components are installed in the engine compartment or near the exhaust system of an automobile, or when large currents flow due to fast charging or rapid acceleration of EVs / HEVs, the stability of electrical contact resistance in high-temperature environments is a crucial characteristic. To evaluate this, the fluctuation of electrical contact resistance was measured by the following heat treatment. For the heat resistance evaluation, the components were heated continuously in an electric furnace at 200°C for 80 hours, meeting the most stringent Class V heat resistance evaluation standard set by the United States Automobile Federation (USCAR), i.e., 200°C, and the change in electrical contact resistance was measured. The measurement conditions were the same as those for measuring electrical contact resistance described above.

[0031] As shown in Figure 7, after heating at 200°C for 80 hours, the average contact resistance of the pure Sn plating (Comparative Example 1) increased from 0.92 mΩ to 6.55 mΩ, and the conductivity decreased by approximately 7 times (7.12). In contrast, the contact resistance of the Sn-graphene composite plating of the present invention remained in the 1 mΩ range, indicating that the increase in resistance was significantly suppressed. This suggests that the graphene on the surface and within the plating layer effectively suppressed the oxidation of Sn in a high-temperature environment. As a result, the Sn-graphene composite plating of the present invention was found to have superior heat resistance and high electrical connection reliability compared to ordinary Sn plating. The average contact resistance before and after heating was compared as follows: In the case of pure Sn plating (Comparative Example 1), the ratio after heating / before heating was 6.55 / 0.92=7.12, indicating a significant deterioration in conductivity. In contrast, for the Sn-Gr01-1A of the present invention (Example 13), the ratio after heating / before heating was 1.81 / 0.64=2.8, for Sn-Gr35-1A (Example 3), it was 1.55 / 0.76=2.0, for Sn-Gr35-2A (Example 4), it was 1.42 / 0.75=1.9, and for Sn-Gr01-3A (Example 5), it was 1.87 / 0.61=3.06. In all cases, the increase in contact resistance was significantly suppressed. The decrease in conductivity according to the above-mentioned heat resistance evaluation criteria is preferably 4 times or less, more preferably 3 times or less, and even more preferably 2 times or less or 2 mΩ or less, from the viewpoint of having excellent heat resistance and high electrical connection reliability after the heat resistance evaluation.

[0032] Furthermore, the manufacturing method for Sn-graphene composite plating can be the same as for various existing Sn-based plating methods, and can be carried out using reel-to-reel (Figure 8 shows one example), batch, or barrel methods, depending on the shape of the substrate and the area to be plated. [Industrial applicability]

[0033] In automobiles, particularly EVs / PHVs, where further expansion is expected, the increasing sophistication of electronic control systems will lead to higher performance and durability of wire harnesses, and in particular, improved conductivity and wear resistance will enable high electrical connection reliability. Furthermore, although this invention describes Sn-graphene composite plating as being used in terminals and connectors for automobiles and EVs / PHVs as an example, it can also be used in electronic components of various electronic devices that also require high conductivity and durability. [Explanation of Symbols]

[0034] 1: Sn-graphene composite plated film component 2, 2': Graphene 3: Sn matrix (Sn layer) 4: Sn-graphene composite plating film 5:Cu base material

Claims

1. A Sn-graphene composite plated film component comprising a substrate for electrical connection (or current conduction) and a Sn-graphene composite plated film produced by hybrid plating on the surface of the substrate, wherein the hybrid plating combines electroplating of Sn and electrophoretic deposition of a graphene sheet, the size of the graphene is 0.01 to 6 μm, and the graphene content is 0.5 to 30 at%.

2. The Sn-graphene composite plated film component according to claim 1, characterized in that the electrical contact resistance of the Sn-graphene composite plated film is 0.8 mΩ or less.

3. The Sn-graphene composite plated film component according to claim 1 or 2, characterized in that the Vickers hardness of the composite plated film is 40 Hv or higher.

4. The Sn-graphene composite plated film component according to any one of claims 1 to 3, characterized in that the material of the substrate includes copper or a copper alloy.

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