JP7199678B2 - Electrical parts and manufacturing methods thereof - Google Patents

Description

The present invention relates to an electrical component comprising a first terminal having a contact surface and a second terminal having a contact contacting the contact surface. The invention also relates to a method for manufacturing this electrical component.

In recent years, the computerization of automobiles is progressing in order to improve the safety performance, environmental performance, and comfort of automobiles. Along with the diversification of electrical parts mounted on automobiles, the number of printed wiring boards for automobiles is increasing, and the number of connector terminals required for connecting them is also increasing.

In addition, the reduction of the number of parts is also important, and the functional integration of electric parts is progressing. As a result, the number of poles per connector terminal is increasing, and the insertion force required for fitting is increasing. Therefore, various studies have been made to reduce the insertion force required when fitting the connector terminals.

Generally, a Cu alloy, which is excellent in electrical conductivity and thermal conductivity, is often used as a material for connector terminals, and its surface is plated with Sn. For example, Patent Document 1 discloses a fitting-type connector terminal manufactured by post-plating and reflowing a stamped copper alloy strip, which has a terminal fitting portion and a soldering portion, and has a terminal fitting portion. The surface roughness of the base material plate surface is formed to be larger than that of the soldered part, the Cu-Sn alloy layer and the Sn layer are formed in this order as the surface coating layer, and the Sn layer is smoothed by reflow treatment Fitting A terminal for a type connector is described. According to the invention described in Patent Document 1, it is possible to realize a low coefficient of friction in the terminal fitting portion and improve the solderability of the soldering portion at the same time.

As described above, there is a demand for electric parts for automobiles, in which the coefficient of friction of the surface of the connector terminals is low and the insertion force of the connector terminals is suppressed to a low level. However, the fitting-type connector terminal described in Patent Document 1 has not yet satisfied these requirements.

JP 2013-139640 A

SUMMARY OF THE INVENTION It is an object of the present invention to provide an electrical component having a low coefficient of friction when a connector terminal is slid, and a reduced insertion force for the connector terminal.

The above-mentioned problem is provided with a first terminal having a contact surface and a second terminal having a contact that contacts the contact surface, and the contact surface and the contact are slidably brought into contact with each other so that the first terminal and the second terminal are connected to each other. An electrical component that conducts electricity with a terminal; the first terminal has a surface plating layer containing Sn as a main component on a base material made of a conductive metal, and the base material has grooves and ridges. , the surface plating layer is formed on the surfaces of the grooves and the ridges, and after the surface plating layer is formed, the width of the grooves is 10 to 200 μm and the width of the ridges is 20 to 300 μm, The problem is solved by providing an electrical component characterized by a groove depth of 2-50 μm. At this time, it is preferable that the surface plating layer is subjected to a reflow treatment. Preferably, the contact surface of the first terminal is a flat surface of the ridge, and the flat surface and the contact of the second terminal are in contact with each other. It is also preferable that the surface plating layer has a thickness of 0.01 to 20 μm.

The above-described problem is a method for manufacturing the above-described electrical component; in manufacturing the first terminal, at least a partial region of the surface of a base material made of a conductive metal is irradiated with a laser, and grooves are formed on the surface of the base material. and a second step of forming a surface plating layer in a plating bath containing Sn ions. At this time, it is preferable to further include a third step of performing a reflow treatment after the second step.

In the electrical component of the present invention, the coefficient of friction is low when the connector terminal is slid, and the slidability is excellent when the first terminal and the second terminal are brought into contact with each other. Therefore, it is possible to obtain an electrical component in which the insertion force of the connector terminal is kept low.

It is the figure which showed the example which set the angle to 45 degrees, and slid a contact surface and a contact. It is the figure which showed an example of the irradiation method of a laser. It is a schematic diagram of a plated article cross section. It is a figure explaining the measuring method of a friction coefficient. 4 is a diagram showing results of sliding tests in Example 1 and Comparative Example 1. FIG. FIG. 5 is a diagram showing the results of a sliding test when the width of the ridge is changed.

The present invention relates to an electrical component comprising a first terminal having a contact surface and a second terminal having a contact contacting the contact surface. In the electrical component of the present invention, the contact surfaces and the contacts are slidably contacted to conduct electricity between the first terminals and the second terminals.

The shape of the contact surface of the first terminal may be a flat surface or a curved surface, and the flat contact surface is particularly preferable. At this time, it is preferable that the contact surface is a convex flat surface and the flat surface and the contact of the second terminal are in contact with each other. On the other hand, the shape of the contact of the second terminal is not particularly limited, but it is preferably a convex curved surface, and a spherical surface or the like is preferably adopted. The form of contact between the first terminal and the second terminal includes line contact, point contact, surface contact, and the like.

In the present invention, the first terminal has a surface plating layer containing Sn as a main component on a base material made of a conductive metal. The substrate used in the present invention is not particularly limited as long as it is made of a conductive metal. Among them, copper or an alloy containing copper as a main component is preferable from the viewpoint of conductive performance. Here, "contained as a main component" means that it contains 50% by mass or more. Although the thickness of the base material is not particularly limited, it is usually 0.01 to 5 mm.

Further, in the present invention, a surface plating layer containing Sn as a main component is formed on the substrate. Here, "contains as a main component" means that 50% by mass or more of Sn is contained.

The thickness of the surface plating layer is preferably 0.01 to 20 μm. If the thickness is less than 0.01 μm, a uniform surface plating layer may not be obtained. The thickness is more preferably 0.1 μm or more, and even more preferably 0.3 μm or more. On the other hand, if the thickness exceeds 20 μm, the coefficient of friction may increase. Moreover, there is a possibility that productivity may decrease. The thickness is more preferably 5 μm or less, and even more preferably 2 μm or less.

In the present invention, it is preferable that an intermediate plated layer is further formed between the substrate and the surface plated layer. The intermediate plating layer includes an intermediate plating layer containing Ni as a main component, a plating layer containing Cu as a main component, an intermediate plating layer containing Ag as a main component, an intermediate plating layer containing Pd as a main component, and an intermediate plating layer containing Au as a main component. and a plated layer containing In as a main component. Among them, an intermediate plated layer containing Ni as a main component is preferable. Here, "mainly composed" means that the intermediate plating layer contains 50% by mass or more of any one of Ni, Cu, Ag, Pd, Au, and In.

Although the thickness of the intermediate plating layer is not particularly limited, it is preferably 0.01 to 20 μm. If the thickness is less than 0.01 μm, a uniform intermediate plating layer may not be obtained. The thickness is more preferably 0.1 μm or more, and even more preferably 0.3 μm or more. On the other hand, if the thickness exceeds 20 μm, productivity may decrease. More preferably, the thickness is 15 μm or less. The intermediate plated layer may be a single layer or multiple layers. In the case of multiple layers, these layers may be layers of the same type or layers of different types. In the case of multiple layers, the above thickness refers to the thickness of a single layer.

In the present invention, the substrate has grooves and ridges, and the surface plating layer is formed on the surfaces of the grooves and ridges. A method for forming the grooves and the ridges is not particularly limited, and a method of forming the grooves and the ridges on the base material in advance and then forming the plated layer on the surface of the base material is exemplified. In addition, when an intermediate plating layer is formed between the base material and the surface plating layer, grooves and ridges are formed after forming the intermediate plating layer on the base material, and then the plating layer is formed on the surface. There is also a method for

The method of forming the grooves and ridges is not particularly limited. Forming methods include a method of forming grooves and ridges with a laser, press working, cutting, electrical discharge machining, photolithography, and the like. Among them, it is preferable that the grooves and the ridges are formed by a laser from the viewpoint that the grooves and the ridges with high dimensional accuracy can be obtained in a short time.

In the present invention, it is important that the width of the ridges is 20-300 μm. If the width of the ridge is out of this range, the sliding performance between the first terminal and the second terminal deteriorates, making it impossible to obtain an electrical component in which the insertion force of the connector terminal is kept low. Here, the width of the ridge means the length in the width direction of the top of the ridge after the surface plating layer is formed. The width of the ridge is preferably 25 μm or more, more preferably 30 μm or more. On the other hand, the width of the ridge is preferably 200 μm or less, more preferably 150 μm or less, even more preferably 110 μm or less, and particularly preferably 95 μm or less.

In the present invention, the groove width is 10-200 μm. The width of the groove is preferably 15 μm or more, more preferably 20 μm or more. On the other hand, the width of the groove is preferably 150 μm or less, more preferably 100 μm or less, and even more preferably 80 μm or less. The width of the groove means the width of the groove after the surface plating layer is formed.

Further, in the present invention, the groove depth is 2 to 50 μm. The depth of the groove is preferably 4 μm or more, more preferably 6 μm or more. On the other hand, the depth of the groove is preferably 40 μm or less, more preferably 30 μm or less. The groove depth refers to the depth of the groove after the surface plating layer is formed.

An electrical component according to the present invention includes a first terminal having a contact surface and a second terminal having a contact that contacts the contact surface. and the second terminal are energized. Therefore, the angle formed by the direction in which the contact surface and the contact slide and the direction of the groove can be defined.

Here, the angle formed by the direction in which the contact surface slides against the contact and the direction of the groove (hereinafter simply referred to as the angle) will be described with reference to the drawings. In FIG. 1, the description will be made by assuming that the first terminal is a plated product and the second terminal is an indenter. FIG. 1 is a diagram showing an example in which the plated product and the indenter are slid at an angle of 45°.

As shown in FIG. 1, when the plated product is moved horizontally from left to right in the drawing, the direction in which the plated product and the indenter slide is the direction of the arrow (sliding direction) shown in FIG. . At this time, since the plated product is slid at an angle of 45° clockwise with respect to the sliding direction, the angle formed by the sliding direction and the direction of the groove is 45°. Therefore, if the plated product is not tilted and moved horizontally from left to right in the drawing, the angle is 0°, and the plated product is tilted clockwise by 90° and moved horizontally from left to right in the drawing. The angle will be 90°.

In the present invention, the angle is not particularly limited. From the viewpoint of further reducing the coefficient of friction when the first terminal and the second terminal are slid, the angle is preferably 60° or less, more preferably 40° or less, and 20° or less. It is even more preferable to have

In the present invention, it is preferable that the surface plating layer containing Sn as a main component is subjected to a reflow treatment. Whisker generation can be suppressed by subjecting the surface plating layer to reflow treatment. The reflow treatment method is not particularly limited, but the treatment method described later is preferable.

Although the method for manufacturing the electrical component of the present invention is not particularly limited, a method including the following first and second steps is preferable when manufacturing the first terminal.

In the first step, at least a partial region of the surface of a base material made of a conductive metal is irradiated with a laser to form grooves on the surface of the base material. The laser used at this time is not particularly limited as long as it can form grooves on the surface of the base material, but it can reduce damage to the base material, and grooves and ridges with excellent dimensional accuracy can be obtained. From the viewpoint of being able to obtain, it is preferably a pulsed laser.

The pulse width of the pulse laser is preferably 1×10 ⁻⁴ seconds or less, more preferably 1×10 ⁻⁷ seconds or less, even more preferably 1×10 ⁻⁹ seconds or less, and 1×10 −9 seconds or less. 10 ⁻¹⁰ seconds or less is particularly preferred. Moreover, it is preferable that the average output at the processing point is 0.01 to 1000W. If the average output at the processing point is less than 0.01 W, it may not be possible to form grooves and ridges on the surface of the substrate. On the other hand, if the average output at the processing point exceeds 1000 W, the damage to the base material is increased. Although the repetition frequency of the pulse laser is not particularly limited, it is usually 1 kHz to 1000 MHz.

The type of laser is also not particularly limited, and solid lasers such as YAG lasers, fiber lasers and semiconductor lasers; and gas lasers such as carbon dioxide lasers and excimer lasers can be used. The wavelength of the pulse laser is not particularly limited, and can be appropriately set depending on the type of substrate used, etc., and is usually 100 to 12000 nm. A YAG laser is preferable, and a neodymium YAG laser is more preferable, from the viewpoint of easy pulse oscillation. A neodymium YAG laser generates laser light of 1064 nm called a fundamental wave (first harmonic). By using a wavelength conversion device, a laser beam with a wavelength of 532 nm called the second harmonic, a laser beam with a wavelength of 355 nm called the third harmonic, and a laser beam with a wavelength of 266 nm called the fourth harmonic can be obtained. In the manufacturing method of the present invention, the first to fourth harmonics can be appropriately selected depending on the purpose.

In the first step, at least a partial region of the surface of the substrate is irradiated with a laser. Although the method of irradiating the base material with laser is not particularly limited, for example, the method shown in FIG. 2 can be mentioned. FIG. 2 is a diagram showing an example of a laser irradiation method. As shown in FIG. 2, an irradiation area is set on the surface of the substrate. Then, the laser is irradiated from the _point indicated by S1 to E1 at _a predetermined scanning speed in the x direction (right direction in FIG. 2). This operation can be repeated, and the depth of the groove can be adjusted by appropriately adjusting the number of repetitions.

Then, the laser is moved by a predetermined distance in the y direction (downward in FIG. 2). Let Δy be the movement distance at this time. Similarly, the laser is irradiated from the point indicated by _S2 to _E2 . That is, the laser is irradiated from S2 to E2 shown in _FIG . _{2 ,} the laser is moved by Δy _, and the laser is irradiated from S3 to E3. This operation is repeated n times. In this case, the width of the ridge can be adjusted by adjusting the moving distance Δy.

In the second step, a surface plating layer is formed on the surface of the substrate in a plating bath containing Sn ions. When the substrate is immersed in the plating bath, the substrate is degreased as necessary. Then, the substrate is immersed in the plating bath and plated in the bath to form a surface plating layer containing Sn as a main component.

The plating method at this time is not particularly limited, and the surface plating layer can be formed by performing electroplating using a known Sn electroplating bath. The current density and plating time are appropriately set so that the surface plating layer has a desired film thickness. The surface plated layer may be formed by electroless plating, or may be formed by combining electroless plating and electroplating. The surface plating layer may be formed by hot dip plating. Thus, a first terminal having a surface plating layer containing Sn as a main component on a base material made of a conductive metal can be obtained.

It is preferable to further include a third step of performing a reflow treatment after the second step. Generation of whiskers can be suppressed by performing the reflow treatment. Here, the reflow treatment refers to a treatment in which Sn is once melted by applying heat to the Sn plating layer and then solidified.

The heating temperature is preferably the melting point of Sn or Sn alloy or higher, more preferably 232° C. or higher, even more preferably 250° C. or higher, and particularly preferably 280° C. or higher. The upper limit of the heating temperature is usually about 400°C. Also, the heating method is not particularly limited, and heat treatment can be performed using a known reflow furnace. When the heat treatment is performed using a reflow furnace, the above temperature means the peak temperature.

The heating time is preferably 0.3 seconds or longer, more preferably 1 second or longer, and even more preferably 5 seconds or longer. The heating time is usually 120 seconds or less.

The manufacturing method of the present invention preferably includes a step of forming an intermediate plated layer before the second step. At this time, it is preferable to form an intermediate plating layer on the surface of the substrate in a plating bath containing any one of Ni ions, Cu ions, Ag ions, Pd ions, Au ions, and In ions. The plating method at this time is not particularly limited, and the intermediate plating layer can be formed by performing electroplating using a known electroplating bath.

Examples of known electroplating baths include Watt's bath, Wood's bath, Ni sulfamate bath, Ni organic acid bath, Cu cyanide bath, Cu sulfate bath, and Cu pyrophosphate bath. The current density and plating time are appropriately set so that the intermediate plating layer has a desired film thickness. The intermediate plated layer may be formed by electroless plating, or may be formed by combining electroless plating and electroplating. Also, this step may be performed multiple times, and the types of plating may be the same or different.

The electrical component of the present invention has a low coefficient of friction when the first terminal and the second terminal are slid. Taking advantage of such characteristics, it can be used as a charging connector for an electric vehicle, a connector for an ECU (Electronic Control Unit) of a vehicle, and the like.

EXAMPLES The present invention will be described in more detail below using Examples, but the present invention is not limited to these.

Example 1
[Laser irradiation]
(Base material)
As a base material, a copper cathode plate for Hull cell (“B-60-P05” manufactured by Yamamoto Plating Tester Co., Ltd.) of 60 mm long×32 mm wide×0.30 mm thick was used.

(processing method)

A pulse oscillation all-solid-state laser "Talisker HE" manufactured by Coherent Japan Co., Ltd. was used.
Wavelength: 355nm
Average output at processing point: 0.8W
Pulse width: 20 picoseconds Frequency: 50 kHz
Scanning speed: 100 mm/sec One spot mark: about 30 μm

The substrate was irradiated with a pulsed laser by the method shown in FIG. Specifically, an irradiation area of 15 mm×15 mm was set on the surface of the substrate. In this irradiation area, _a pulse laser was irradiated from the _point indicated by S1 to the right end (E1) of the irradiation area in the x direction. Then, the pulse laser was moved in the -y direction, and similarly the pulse laser was irradiated from the point indicated by S2 to the right end ₍ E2) of the irradiation area in the _x direction. By repeating these operations, the entire irradiation area was irradiated with the pulse laser.

[Plating]
(Preprocessing)
The base material laser-processed by the above method was immersed in an electrolytic degreasing aqueous solution (“Pakuna THE-210” manufactured by Yuken Kogyo Co., Ltd., concentration: 50 g/L) heated to 50°C. Then, using the substrate as a cathode, a current density of 5 A/dm ² was applied for 60 seconds to perform degreasing treatment. The degreased substrate was washed with ion-exchanged water three times, and then immersed in a 10 vol % sulfuric acid aqueous solution at room temperature for 60 seconds for acid cleaning. Subsequently, it was washed again with water three times.

(Formation of Ni plating layer)
The pretreated substrate was immersed in a Ni plating solution (see below for composition) kept at 50°C. Subsequently, while air stirring was performed, the product was electroplated with Ni at a cathode current density of 5 A/dm ² for 88 seconds to obtain a plated article having a single-layer plating layer formed thereon. Then, this plated product was washed with deionized water three times. The thickness of the Ni plating layer was about 1.5 μm.
・Nickel sulfamate [Ni _{( NH2SO3} ) _2.4H2O ]: _600g /L
・Nickel chloride [ _NiCl2.6H2O ]: _35g /L
・Boric acid [ _H3BO3 ]: _35g /L

(Formation of Sn plating layer)
The plated article on which the single-layer plating layer was formed was immersed in a Sn plating solution (see below for composition) kept at 40°C. Then, while air stirring, the product was electroplated with Sn at a cathode current density of 5 A/dm ² for 24 seconds to obtain a plated product having a multi-layered plating layer. Then, this plated product was washed with deionized water three times. The thickness of the Sn plating layer was about 1.0 μm.
・ “PF-SN15” manufactured by Ishihara Chemical Co., Ltd.: 330 g / L
・ “PF-A” manufactured by Ishihara Chemical Co., Ltd.: 100 mL / L
・ “PF-098” manufactured by Ishihara Chemical Co., Ltd.: 20 mL / L

The plated product with the Sn plating layer formed thereon was immersed in an anti-tarnishing agent (“501SN” manufactured by Ishihara Chemical Co., Ltd.: 100 mL/L) kept at 50° C. for 30 seconds. Then, the plated article was washed with ion-exchanged water three times, and then dried at 80° C. for 20 seconds.

(reflow treatment)
The plated product with the multilayer plating layer formed thereon was introduced into a reflow furnace and subjected to reflow treatment at a peak temperature of 300° C. for 20 seconds to obtain a reflow-treated plated product.

Here, a schematic diagram of the cross section of the plated product is shown. In FIG. 3, a is the width of the portion not irradiated with the laser (width of the ridge), b is the width of the portion irradiated with the laser (the width of the groove), and c is the depth of the groove. When a, b, and c were measured with a laser microscope, a was 50 μm, b was 30 μm, and c was 8 μm.

[Sliding test]
The coefficient of friction was measured using a surface property measuring instrument (“Tribogear HEIDON-14DR” manufactured by Shinto Kagaku Co., Ltd.). Specifically, as shown in Fig. 4, the plated product is fixed on the stage of the measuring machine, a load is applied to the surface of the plated product with an indenter, and the resistance is measured under the following conditions while moving the stage. bottom. The results are shown in FIG. 5 and Table 1.
Load: 3N
Stage movement speed: 10mm/s
Stage movement distance: 12mm
Indenter: An indenter with a tip radius R = 1 mm, which is obtained by subjecting the Cu base material to Ni/Sn plating treatment Width of contact between the indenter and the plated product: Average of about 120 µm
Angle between sliding direction and groove direction: 0°

Here, "the angle formed by the direction of sliding and the direction of the groove" means, as described above with reference to FIG. It is an angle corresponding to "the angle formed by That is, when the angle between the sliding direction and the groove is 0°, it means that the moving direction of the stage is parallel to the direction of the groove.

Comparative example 1
A plated product was produced in the same manner as in Example 1, except that laser irradiation was not performed. Therefore, grooves and ridges are not formed in the obtained plated product. Then, a sliding test was performed in the same manner as in Example 1 using this plated product. The results are shown in FIG. 5 and Table 1. The average coefficient of friction was 0.323μ.

Examples 2-10, Comparative Examples 2-7
A sliding test was conducted in the same manner as in Example 1 except that the width (a) of the ridge, the width (b) of the groove, and the depth (c) of the groove were changed as shown in Table 2. The results are shown in FIG. 6 and Table 2.

Examples 13-15, Comparative Examples 8-13
In the sliding test, the sliding test was conducted in the same manner as in Example 1, except that the angle formed by the sliding direction (moving direction of the stage) and the groove direction was changed as shown in Table 3. Table 3 shows the results. Table 3 also shows the average friction coefficient in Example 1.

Claims (6)

A first terminal having a contact surface and a second terminal having a contact contacting the contact surface are provided, and the contact surface and the contact slide and contact each other to conduct electricity between the first terminal and the second terminal. an electrical component that performs
The first terminal has a surface plating layer containing Sn as a main component on a base material made of a conductive metal,
The base material has grooves and ridges, and the surface plating layer is formed on the surfaces of the grooves and ridges,
After the surface plating layer is formed, the width of the groove is 30-50 μm, the width of the ridge is 40-110 μm, the depth of the groove is 8-16 μm, and the direction of sliding and the direction of the groove. An electrical part characterized in that the angle between the two is 20° or less. 2. The electrical component according to claim 1, wherein said surface plating layer is subjected to reflow treatment. 3. The electrical component according to claim 1, wherein the contact surface of the first terminal is a flat surface of the ridge, and the flat surface and the contact of the second terminal are in contact with each other. The electrical component according to any one of claims 1 to 3, wherein the surface plating layer has a thickness of 0.01 to 20 µm. A method for manufacturing an electrical component according to any one of claims 1 to 4;
When manufacturing the first terminal,
a first step of irradiating at least a partial region of the surface of a base material made of a conductive metal with a laser to form grooves on the surface of the base material;
and a second step of forming a surface plating layer in a plating bath containing Sn ions. 6. The manufacturing method according to claim 5, further comprising a third step of performing reflow treatment after the second step.

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