JP2009242888A - Composite plated material and method for manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a composite plated material and a method for manufacturing the material that requires no reflow treatment, has low frictional coefficient, and can be used as a material for a terminal that can achieve both of reduction in insertion force in a fitting part and improvement of solder wettability in a soldering part. <P>SOLUTION: The method for manufacturing a composite plated material comprises forming a coating film of a composite material containing carbon particles in a tin layer on a base material 120 by electroplating by use of a composite plating liquid 116 prepared by adding carbon particles to a tinning liquid, wherein the electroplating is carried out while controlling a Reynolds number of not less than 18,000, which indicates a flow state of the composite plating liquid 116, by stirring the composite plating liquid 116 by rotation of stirring blades 114 or by pressure-feeding and stirring the composite plating liquid 116 by a pump. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a composite plating material in which a film made of a composite material in which carbon particles are dispersed in a tin layer is formed on the material, and a method for producing the same, and in particular, composite plating used as a material such as a connectable / detachable connection terminal. The present invention relates to a material and a manufacturing method thereof.

  Conventionally, a tin-plated material obtained by applying tin plating to the outermost layer of a conductor material such as copper or copper alloy has been used as a material for a connection terminal that can be inserted and removed. In particular, tin-plated materials have low contact resistance, such as wire harness connector terminals used for in-vehicle and consumer electrical wiring and printed circuit board connector (male) terminals (hereinafter referred to as “PCB terminals”). Used as a material.

  Generally, many PCB terminals are attached to a printed circuit board connector, and each of these PCB terminals is fitted with a soldering portion on one end soldered to the printed circuit board and a mating member. And a fitting portion as an electrical contact portion on the other end side that is fitted to the portion and ensures energization. When a tin plating material is used as a material for such a PCB terminal, a connection terminal having a fitting portion with low contact resistance and excellent corrosion resistance and a soldering portion with good solderability can be obtained.

  In recent years, there has been an increasing demand for miniaturization and high density of PCB terminals (increase in the number per unit area). Therefore, insertion when fitting a fitting portion of a PCB terminal to a mating portion of a mating member is performed. There is a need to reduce power. However, since the tin plating film on the outermost layer of the tin plating material is a soft metal, it is easily plastically deformed when the fitting portion of the PCB terminal is fitted to the mating portion of the mating material, and a large insertion Power is needed.

In order to reduce the insertion force of the fitting part of such a PCB terminal, it is conceivable to make the tin plating film thin. However, if the tin plating film is made thin, there is a problem that the solderability of the soldering part deteriorates. is there. In addition, a nickel plating layer, a copper plating layer, and a tin plating layer are sequentially laminated on the surface of a copper alloy base material such as brass, and then a reflow process is performed to partially transfer the copper tin alloy layer. It has been proposed to increase the hardness of the outermost layer and reduce the insertion force of the terminal by converting into a layer (see, for example, Patent Document 1). In addition, a Cu plating layer and a Sn plating layer are sequentially formed on the surface of the base material made of Cu plate, and then reflow treatment is performed, so that the Cu—Sn alloy coating layer and the Sn coating layer are formed on the surface of the base material in this order. It has also been proposed to reduce the insertion force of the terminal by forming it (see, for example, Patent Document 2). Further, by performing electroplating using a tin plating solution to which carbon particles and an aromatic carbonyl compound are added, a film made of a composite material containing carbon particles in a tin layer is formed on the material, thereby forming a terminal. It has also been proposed to reduce the insertion force (see, for example, Patent Document 3).

Japanese Patent No. 3562719 (paragraph numbers 0007-0008) Japanese Patent Laying-Open No. 2006-77307 (paragraph numbers 0009-0012) JP 2007-2285 A (paragraph number 0010-0013)

  However, in Patent Literatures 1 to 3, the insertion force of the fitting portion can be reduced, but there is a problem that the solder wettability of the soldering portion is reduced. In addition, in the terminals of Patent Literatures 1 and 2, Since it is necessary to perform reflow processing, there is a problem that man-hours and costs increase accordingly. Therefore, there is a demand for a plating material that can be used as a material for a terminal capable of both reducing the insertion force of the fitting portion and improving the solder wettability of the soldering portion.

  Therefore, in view of such a conventional problem, the present invention does not require reflow processing, has a low friction coefficient, and achieves both reduction in insertion force of the fitting portion and improvement in solder wettability of the soldering portion. It aims at providing the composite plating material which can be used as a material of a possible terminal, and its manufacturing method.

  As a result of intensive studies to solve the above problems, the inventors of the present invention include carbon particles in a tin layer by performing electroplating using a composite plating solution in which carbon particles are added to a tin plating solution. In the method of manufacturing a composite plating material for forming a coating film made of a composite material, if electroplating is performed in a state where the Reynolds number of the composite plating solution is 18000 or more, there is no need to perform reflow treatment, and the friction coefficient is low. And found that a composite plating material can be produced that can be used as a material for a terminal capable of both reducing the insertion force of the fitting portion and improving the solder wettability of the soldering portion, and completed the present invention. It came to do.

  That is, the method for producing a composite plating material according to the present invention includes a film comprising a composite material containing carbon particles in a tin layer by performing electroplating using a composite plating solution in which carbon particles are added to a tin plating solution. In the method for producing a composite plating material on the material, electroplating is performed in a state where the Reynolds number of the composite plating solution is 18000 or more. In this method of manufacturing a composite plating material, the Reynolds number may be increased to 18000 or more by stirring the composite plating solution by rotating a stirring blade, or the Reynolds number by pumping and stirring the composite plating solution. May be 18000 or more. Moreover, it is preferable that an aromatic carbonyl compound is added to the composite plating solution.

  In the composite plating material according to the present invention, a coating made of a composite material containing carbon particles in a tin layer is formed on the material, and the friction coefficient between the same species is 0.19 or less, and the treatment with flux is not performed. The zero cross time when evaluating the solder wettability is 5 seconds or less. In this composite plating material, the coefficient of friction is preferably 0.15 or less, and the thickness of the film is preferably 0.5 to 3.0 μm or less. Further, the carbon content in the film is preferably 1.0 to 3.0% by mass, and the contact resistance is preferably 1.0 mΩ or less.

  According to the present invention, it is not necessary to perform a reflow process, the friction coefficient is low, and it can be used as a material for a terminal capable of both reducing the insertion force of the fitting portion and improving the solder wettability of the soldering portion. A composite plating material can be manufactured.

  In the embodiment of the method for producing a composite plating material according to the present invention, by performing electroplating using a composite plating solution in which carbon particles are added to a tin plating solution, the composite material containing carbon particles in the tin layer is used. In the method for manufacturing a composite plating material for forming a coating film on a material, electroplating is performed in a state where the Reynolds number indicating the flow state of the composite plating solution is 18000 or more. In order to set the Reynolds number of the composite plating solution to 18000 or more, the composite plating solution may be stirred by rotation of a stirring blade, or the composite plating solution may be pumped and stirred.

  By setting the Reynolds number of the composite plating solution to 18000 or more, the solder wettability of the composite plating layer (Sn—C plating layer) in which carbon particles are dispersed in the conventional tin layer can be dramatically improved. Thus, when the plating layer formed by electroplating in a state where the Reynolds number of the composite plating solution is 18000 or more is observed with a microscope, the surface of the plating layer becomes smooth, and the size of the Sn grain boundary becomes small. It is observed that the solder wettability of the composite plating material is improved by smoothing the surface of the plating layer and reducing the size of the Sn grain boundary.

  The Reynolds number (Re) is a dimensionless number representing the flow state. The flow state is laminar when Re <2100, transition flow when 2100 <Re <4000, and Re> 4000. Classified as turbulent.

As shown in FIG. 1, when using a cylindrical container as the plating tank 12 and using a plating apparatus 10 that stirs the plating solution 16 by feeding the plating solution 16 in the direction of the arrow with the pump 14, When the viscosity of the solution is μ (kg / (m · s)), the density of the plating solution is ρ (kg / m ³ ), the typical length of the flow is d (m), and the flow velocity is u (m / s), The Reynolds number (Re) is represented by Re = duρ / μ. For example, plating solution viscosity μ = 1 mPa · s = 0.001 kg / (m · s), plating solution density ρ = 1130 kg / m ³ , typical flow length d = 0.30 m, flow velocity u = 0.18 m If it is / s, Re = 61020.

Further, as shown in FIG. 2, a plating apparatus that uses a cylindrical container as the plating tank 112 and stirs the plating solution 116 by rotating the stirring blade 114 disposed in the plating tank 112 in the direction of the arrow. When 110 is used, the viscosity of the plating solution is μ (kg / (m · s)), the density of the plating solution is ρ (kg / m ³ ), the diameter of the stirring blade is d (m), and the rotation speed of the stirring blade Is n (1 / s), the Reynolds number (Re) is expressed as Re = nd ² ρ / μ. For example, plating solution viscosity μ = 1 mPa · s = 0.001 kg / (m · s), plating solution density ρ = 1130 kg / m ³ , stirring blade diameter d = 0.035 m, stirring blade rotation speed n = If 1000 rpm = 1000/60 (1 / s), Re = 23071. In FIG. 2, reference numeral 118 indicates an anode (Sn electrode), and 120 indicates a cathode (work).

  As the tin plating solution, various tin plating solutions made of sulfuric acid or organic acid can be used, but a tin plating solution made of alkanol sulfonic acid is preferably used. Various carbon particles can be used as the carbon particles added to the tin plating solution, but it is preferable to use scale-like or earth-like graphite particles.

  Moreover, it is preferable to further add an aromatic carbonyl compound to the composite plating solution obtained by adding carbon particles to the tin plating solution. As the aromatic carbonyl compound, an aromatic aldehyde or an aromatic ketone is preferably used. By adding an aromatic carbonyl compound to the tin plating solution, the carbon particles become weakly aggregated and dispersed in the tin plating solution, and a film in which the carbon particles are dispersed in an island shape in the tin matrix can be formed. . Thus, a film having a very low friction coefficient can be formed by controlling the aggregation state of the carbon particles in the tin matrix.

  The concentration of carbon particles in the tin plating solution is preferably less than 50 g / L, more preferably 1 to 40 g / L, and most preferably 5 to 30 g / L. If it is less than 1 g / L, the carbon particles are insufficient to build a surface structure and complex, and if it is 50 g / L or more, the amount of carbon particles to be complexed increases, so that the carbon particles are contained in the tin matrix. This is because it is impossible to form a film dispersed in an appropriate aggregated state.

Moreover, it is preferable that the current density in the case of electroplating is 5-15 A / dm < ² >. If it is less than 5 A / dm ² , the productivity is poor, and if it exceeds 15 A / dm ² , plating burns occur.

  In addition, as a raw material which forms a film | membrane, an iron-type or aluminum-type raw material other than copper alloys, such as brass, can be used. Moreover, it is preferable to perform a pretreatment (such as electrolytic degreasing, washing with water, pickling, washing with water) on the surface of the material before electroplating.

  Since the embodiment of the tin plating material according to the present invention is characterized by the structure of the outermost surface and is not affected by the base, the base plating is selected from various base platings such as Sn, Cu, and Ni depending on the material and application. can do. Further, when Sn plating is performed as the base plating, the wear resistance can be improved by increasing the film thickness without changing the aggregate structure of the carbon particles on the outermost surface.

  According to the embodiment of the method for producing a tin-plated material according to the present invention described above, a film made of a composite material in which appropriately aggregated carbon particles are appropriately dispersed in a tin layer is formed on the material, and the friction coefficient between the same types 0.19 or less, preferably 0.15 or less, zero cross time when solder wettability is evaluated without performing treatment with flux is 5 seconds or less, and film thickness is 0.5 to 3.0 μm, preferably 0 A composite plating material having a thickness of 0.5 to 1.0 μm, a carbon content in the film of 1.0 to 3.0 mass%, and a contact resistance of 1.0 mΩ or less can be produced.

  Hereinafter, examples of the composite plating material and the manufacturing method thereof according to the present invention will be described in detail.

[Example 1]
First, 60 g / L of metallic tin (containing 600 mL / L of tin alkanol sulfonate (Metas SM manufactured by Yuken Industry) as a metal tin salt) and 113 g / L of free acid (alkanol sulfonic acid (manufactured by YUKEN Industry Co., Ltd. as a free acid)) METASU AM) containing 130 mL / L) was prepared. In order to obtain a good tin plating film, 20 mL / L of a tin plating surfactant (Metas LSA-M manufactured by Yuken Industry) was added to the tin plating solution, and flaky graphite particles having an average particle size of 3.4 μm. (Graphic SGP-3 manufactured by ESC) 5 g / L was added and dispersed, and benzaldehyde 30 mL / L was added as an aromatic carbonyl compound to control the aggregation state of the graphite particles, and a composite plating solution was prepared. did. The average particle size of the graphite particles was determined by dispersing 0.5 g of graphite particles in 50 g of a 0.2 mass% sodium hexametaphosphate solution and further dispersing by ultrasonic waves, and then using a laser light scattering particle size distribution measuring device. It was determined by measuring and taking 50% of the cumulative distribution as the average particle size.

Next, from the Cu-Ni-Sn alloy material (NB-109EH manufactured by DOWA Metaltech Co., Ltd.) having a thickness of 0.25 mm in the plating tank (300 mm diameter cylindrical container) of the plating apparatus shown in FIG. The material and the tin plate as the anode are arranged and filled with the above composite plating solution, the flow rate of the composite plating solution is 0.18 m / s (the viscosity of the composite plating solution is 0.001 kg / (m · s), The liquid feeding amount of the pump is set so that the specific gravity of the composite plating solution is 1130 kg / m ³ and the Reynolds number (Re) is Re = duρ / μ = 61020), and the plating solution is fed by the pump. While being stirred, electroplating was performed at a liquid temperature of 25 ° C. and a current density of 10 A / dm ² to prepare a composite plating material on which a composite plating film of tin and graphite particles having a film thickness of 1.0 μm was formed. In addition, the film thickness of the composite plating film was calculated from the average value of 4 points by the fluorescent X-ray film thickness measurement method.

  About the obtained composite plating material, the friction coefficient, solder wettability, carbon content, and contact resistance were evaluated. The solder wettability was evaluated from the zero cross time, and the coefficient of friction, zero cross time, carbon content, and contact resistance were measured three times, and the average value was evaluated.

  About the friction coefficient of the composite plating material, the friction coefficient of the two test pieces cut out from the obtained composite plating material was calculated | required. This coefficient of friction was obtained by indenting (R3 mm) one test piece cut out from the obtained tin-plated material into an indenter, and using the other flat test piece as a base side evaluation sample, Using a load cell, the indenter was slid at a sliding speed of 60 mm / min while pressing the indenter against the surface of the evaluation sample with a contact load of 3 N. The average value of the coefficient of friction at a sliding distance of 2 to 5 mm out of a sliding distance of 7 mm was obtained. As a result, in this example, the coefficient of friction was 0.07.

The evaluation of the solder wettability of the composite plating material was performed using a test piece (10 mm × 25 mm) cut out from the obtained composite plating material and a test piece that was treated with a flux (UFL-300R manufactured by Tamura Chemical Research). Zero cross time when the pieces were immersed in a solder bath (Sn-37Pb, 200 ° C. ± 1 ° C.) at an immersion speed of 20 ± 5 mm / second, an immersion time of 10 ± 1 second, and an immersion depth of 2 mm (immersion after immersion) This was carried out by measuring the time until the part was wet (solder wet time). This measurement is based on JIS
According to the menisco conditions of C 0053, the test was performed with a menisco testing machine (SAT-5100 manufactured by Reska Co., Ltd.). As a result, the zero cross time when the flux treatment was performed was 1.6 seconds, and the zero cross time when the flux treatment was not performed was 3.1 seconds. In particular, the solder wettability of the composite plating material can be directly evaluated if it is evaluated without performing the treatment with the flux, and the zero cross time when the treatment with the flux is not performed is 5 seconds or less (within 5 seconds). When wet, the solder wettability was evaluated as good.

  The carbon content in the composite plating film was determined by preparing test pieces cut out from the obtained composite plating material (including raw materials) for the analysis of tin and carbon, respectively, and the tin content X (mass%) in the test pieces. ) And tin content Y (mass%) in the material not subjected to composite plating is obtained by plasma spectroscopy using an ICP apparatus (IRIS / AR manufactured by Jarrel Ash), and carbon in the test piece Content Z (mass%) was determined by a combustion infrared absorption method using a trace carbon / sulfur analyzer (EMIA-U510 manufactured by Horiba Seisakusho) and calculated as Z × 100 / (XY + Z). As a result, in this example, the carbon content was 1.4% by mass.

  The contact resistance of the composite plating material was measured by changing the sliding load from 0 to 100 gf with an open circuit voltage of 200 mV and a current of 10 mA by the AC four-terminal method of JIS C5402, and measuring the value at 100 gf. As a result, the contact resistance was 0.60 mΩ.

[Example 2]
A plating apparatus similar to the plating apparatus of FIG. 2 having an inner diameter of a cylindrical plating tank of 100 mm is prepared, a stirring blade having a diameter of 35 mm and a height of 14 mm, a cathode (Sn electrode) having a size of 70 mm × 80 mm, and 70 mm Using an anode (workpiece) with a size of × 100 mm, putting 0.9 L of the same composite plating solution as in Example 1 in the plating tank to a height of 115 mm of the composite plating solution, and rotating the stirring blade at 1000 rpm Except for performing electroplating while stirring (reynolds number (Re) is Re = nd ² ρ / μ = 23071), tin and graphite having a film thickness of 1.0 μm are formed in the same manner as in Example 1. A composite plating material on which a composite plating film of particles was formed was produced. About the obtained composite plating material, when a friction coefficient, solder wettability, carbon content, and contact resistance were evaluated by the same method as Example 1, the friction coefficient was 0.07 and the process by a flux was performed. In this case, the zero cross time was 1.5 seconds, the zero cross time when the flux treatment was not performed was 3.7 seconds, the carbon content was 1.6 mass%, and the contact resistance was 0.62 mΩ.

[Example 3]
A tin film having a thickness of 1.0 μm was formed in the same manner as in Example 2 except that the amount of graphite particles added to the tin plating solution was 20 g / L and the rotation speed of the stirring blade was 800 rpm (Reynolds number Re = 18457). A composite plating material on which a composite plating film of graphite particles was formed was prepared. About the obtained composite plating material, when the friction coefficient, the solder wettability, the carbon content and the contact resistance were evaluated by the same method as in Example 1, the friction coefficient was 0.10, and the treatment with the flux was performed. The zero cross time in the case was 1.8 seconds, the zero cross time in the case where the flux treatment was not performed was 3.8 seconds, the carbon content was 1.4 mass%, and the contact resistance was 0.71 mΩ.

[Example 4]
A composite plating material in which a composite plating film of tin and graphite particles having a thickness of 1.0 μm was formed by the same method as in Example 3 except that the amount of graphite particles added to the tin plating solution was changed to 5 g / L. did. About the obtained composite plating material, when a friction coefficient, solder wettability, carbon content, and contact resistance were evaluated by the same method as Example 1, the friction coefficient was 0.13 and it processed with the flux. In this case, the zero cross time was 1.8 seconds, the zero cross time when the flux treatment was not performed was 3.3 seconds, the carbon content was 1.0 mass%, and the contact resistance was 0.71 mΩ.

[Example 5]
A composite plating material on which a composite plating film of tin and graphite particles was formed was produced by the same method as in Example 3 except that the plating time was adjusted to 0.55 μm. About the obtained composite plating material, when a friction coefficient, solder wettability, carbon content, and contact resistance were evaluated by the same method as Example 1, the friction coefficient was 0.15 and the process by a flux was performed. In this case, the zero cross time was 1.8 seconds, the zero cross time when the flux treatment was not performed was 3.5 seconds, the carbon content was 1.0 mass%, and the contact resistance was 0.91 mΩ.

[Example 6]
A composite plating material on which a composite plating film of tin and graphite particles was formed was produced in the same manner as in Example 3 except that the plating time was adjusted to 3.0 μm. About the obtained composite plating material, when the friction coefficient, the solder wettability, the carbon content and the contact resistance were evaluated by the same method as in Example 1, the friction coefficient was 0.09, and the treatment with the flux was performed. The zero cross time in the case was 1.8 seconds, the zero cross time in the case where the flux treatment was not performed was 3.3 seconds, the carbon content was 1.5 mass%, and the contact resistance was 0.61 mΩ.

[Example 7]
A composite plating material on which a composite plating film of tin and graphite particles having a thickness of 1.0 μm was formed was produced in the same manner as in Example 3 except that the amount of graphite particles added to the plating solution was 50 g / L. . About the obtained composite plating material, when the friction coefficient, the solder wettability, the carbon content and the contact resistance were evaluated by the same method as in Example 1, the friction coefficient was 0.09, and the treatment with the flux was performed. In this case, the zero cross time was 1.9 seconds, the zero cross time without the flux treatment was 3.8 seconds, the carbon content was 2.7% by mass, and the contact resistance was 1.00 mΩ.

[Comparative Example 1]
Except that no graphite particles were added to the tin plating solution, matte Sn plating was performed by the same method as in Example 1 to form a 1.0 μm thick plating film, and then reflow treatment at 400 ° C. for 10 seconds. By doing this, the reflow-processed Sn plating material was produced. About the obtained composite plating material, when a friction coefficient, solder wettability, carbon content, and contact resistance were evaluated by the same method as Example 1, the friction coefficient was 0.24 and the process by a flux was performed. In this case, the zero crossing time was 0.9 seconds, the carbon content was 0% by mass, and the contact resistance was 0.67 mΩ. In addition, about the measurement of the zero crossing time when not performing a flux process, since it did not get wet by flipping a solder, it was not able to be measured.

[Comparative Example 2]
A composite plating material on which a composite plating film of tin and graphite particles having a film thickness of 1.0 μm was formed by the same method as in Example 3 except that the rotation speed of the stirring blade was set to zero (Reynolds number Re = 0). did. About the obtained composite plating material, when a friction coefficient, solder wettability, carbon content, and contact resistance were evaluated by the same method as Example 1, the friction coefficient was 0.16 and the process by a flux was performed. In this case, the zero crossing time was 2.1 seconds, the carbon content was 1.3% by mass, and the contact resistance was 1.40 mΩ. In addition, about the measurement of the zero crossing time when not performing a flux process, since it did not get wet by flipping a solder, it was not able to be measured.

[Comparative Example 3]
A composite plating material on which a composite plating film of tin and graphite particles having a film thickness of 1.0 μm was formed by the same method as in Example 3 except that the rotation speed of the stirring blade was changed to 50 rpm (Reynolds number Re = 1154). did. About the obtained composite plating material, when a friction coefficient, solder wettability, carbon content, and contact resistance were evaluated by the same method as Example 1, the friction coefficient was 0.11, and the process by a flux was performed. In this case, the zero cross time was 1.8 seconds, the carbon content was 1.5 mass%, and the contact resistance was 0.57 mΩ. In addition, about the measurement of the zero crossing time when not performing a flux process, since it did not get wet by flipping a solder, it was not able to be measured.

[Comparative Example 4]
A composite plating material on which a composite plating film of tin and graphite particles having a film thickness of 1.0 μm was formed by the same method as in Example 3 except that the rotation speed of the stirring blade was changed to 100 rpm (Reynolds number Re = 2307). did. About the obtained composite plating material, when a friction coefficient, solder wettability, carbon content, and contact resistance were evaluated by the same method as Example 1, the friction coefficient was 0.11, and the process by a flux was performed. In this case, the zero crossing time was 2.0 seconds, the carbon content was 1.6% by mass, and the contact resistance was 1.20 mΩ. In addition, about the measurement of the zero crossing time when not performing a flux process, since it did not get wet by flipping a solder, it was not able to be measured.

[Comparative Example 5]
Except that the amount of graphite particles added to the tin plating solution was changed to 5 g / L and the rotation speed of the stirring blade was changed to 500 rpm (Reynolds number Re = 1535), tin having a film thickness of 1.0 μm was obtained in the same manner as in Example 2. A composite plating material on which a composite plating film of graphite particles was formed was prepared. About the obtained composite plating material, when a friction coefficient, solder wettability, carbon content, and contact resistance were evaluated by the same method as Example 1, the friction coefficient was 0.13 and it processed with the flux. In this case, the zero crossing time was 2.0 seconds, the carbon content was 1.0 mass%, and the contact resistance was 0.65 mΩ. In addition, about the measurement of the zero crossing time when not performing a flux process, since it did not get wet by flipping a solder, it was not able to be measured.

[Comparative Example 6]
A composite plating material on which a composite plating film of tin and graphite particles having a film thickness of 1.0 μm was formed by the same method as in Example 3 except that the rotation speed of the stirring blade was 600 rpm (Reynolds number Re = 13847). did. About the obtained composite plating material, when the friction coefficient, the solder wettability, the carbon content and the contact resistance were evaluated by the same method as in Example 1, the friction coefficient was 0.09, and the treatment with the flux was performed. In this case, the zero crossing time was 1.8 seconds, the carbon content was 1.4% by mass, and the contact resistance was 0.83 mΩ. In addition, about the measurement of the zero crossing time when not performing a flux process, since it did not get wet by flipping a solder, it was not able to be measured.

[Comparative Example 7]
A composite plating material in which a composite plating film of tin and graphite particles having a film thickness of 1.0 μm was formed by the same method as in Example 3 except that the amount of graphite particles added to the tin plating solution was 2 g / L. did. About the obtained composite plating material, when a friction coefficient, solder wettability, carbon content, and contact resistance were evaluated by the same method as Example 1, the friction coefficient was 0.20 and the process by a flux was performed. In this case, the zero cross time was 1.8 seconds, the zero cross time when the flux treatment was not performed was 3.5 seconds, the carbon content was 0.7 mass%, and the contact resistance was 0.81 mΩ.

[Comparative Example 8]
A composite plating material in which a composite plating film of tin and graphite particles having a thickness of 1.0 μm was formed by the same method as in Example 3 except that the amount of graphite particles added to the tin plating solution was changed to 60 g / L. did. About the obtained composite plating material, when the friction coefficient, the solder wettability, the carbon content and the contact resistance were evaluated by the same method as in Example 1, the friction coefficient was 0.09, and the treatment with the flux was performed. In this case, the zero cross time was 1.8 seconds, the zero cross time without the flux treatment was 3.6 seconds, the carbon content was 3.1 mass%, and the contact resistance was 2.00 mΩ.

  The results of Examples and Comparative Examples are shown in Table 1.

  The composite plating material according to the present invention can be used as a material for a wire harness connector terminal or a PCB terminal used for in-vehicle or consumer electrical wiring.

It is a figure which shows roughly an example of the plating apparatus which can be used for embodiment of the manufacturing method of the composite plating material by this invention. It is a figure which shows schematically the other example of the plating apparatus which can be used for embodiment of the manufacturing method of the composite plating material by this invention.

Explanation of symbols

10, 110 plating equipment,
12, 112 Plating tank 14 Pump 16, 116 Plating solution 114 Stirring blade 118 Anode (Sn electrode)
120 Cathode (work)

Claims (9)

In a method for producing a composite plating material, a film made of a composite material containing carbon particles in a tin layer is formed on a material by electroplating using a composite plating solution obtained by adding carbon particles to a tin plating solution. Electroplating is performed in a state where the Reynolds number of the composite plating solution is set to 18000 or more. The method for producing a composite plating material according to claim 1, wherein the Reynolds number is set to 18000 or more by stirring the composite plating solution by rotating a stirring blade. The method for producing a composite plating material according to claim 1, wherein the Reynolds number is set to 18000 or more by pumping and stirring the composite plating solution. The method for producing a composite plating material according to any one of claims 1 to 3, wherein an aromatic carbonyl compound is added to the composite plating solution. A film composed of a composite material containing carbon particles in a tin layer is formed on the material, and the friction coefficient of the same type is 0.19 or less, and zero crossing when solder wettability is evaluated without performing treatment with flux A composite plating material characterized in that the time is 5 seconds or less. The composite plating material according to claim 5, wherein the friction coefficient is 0.15 or less. The composite plating material according to claim 5 or 6, wherein the film has a thickness of 0.5 to 3.0 µm or less. The composite plating material according to any one of claims 5 to 7, wherein a carbon content in the film is 1.0 to 3.0 mass%. The composite plating material according to claim 5, wherein the contact resistance is 1.0 mΩ or less.

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