JP4514061B2 - Plating material, manufacturing method thereof, and electric / electronic parts using the same - Google Patents

Description

  The present invention relates to a plating material, a manufacturing method thereof, and an electric / electronic component using the plating material. More specifically, the present invention relates to a plating material having good heat resistance and suitable as a material for a connector used in a high-temperature environment such as an automobile engine room. The present invention also relates to a plating material suitable as a material for a fitting connector or a contactor used in a high temperature environment because it has both good heat resistance and insertion / extraction.

  A material in which a plated layer made of Sn or Sn alloy is provided on a conductive substrate made of Cu or Cu alloy is a material having excellent conductivity and strength of the substrate and good electrical contact characteristics of Sn or Sn alloy, It is known as a high-performance conductor that has both corrosion resistance and solderability. This material is widely used for various terminals and connectors.

  As such a material, a material produced by applying a Cu or Ni base plating on a base material and then directly applying a Sn or Sn alloy plating thereon is used. This base plating layer is provided in order to prevent the base material component (alloy component such as Cu or Zn) from diffusing into the surface Sn or Sn alloy. In particular, when the base plating layer is a plating layer made of Ni or a Ni alloy, the effect of delaying the above diffusion to the Sn or Sn alloy on the surface is great even under a high temperature environment. Therefore, the characteristics of Sn and Sn alloy on the surface are ensured for a long time.

  However, even in the case of the above-described material having a Ni or Ni alloy base plating layer, the following problems occur. For example, when it is used at a particularly high temperature, such as in the vicinity of an engine in an automobile engine room, the base material Cu, the underlying Ni, and the Ni alloy diffuse over time to the surface plating layer side. After a certain period of time, the surface plating layer is no longer the original Sn or Sn alloy, and the surface plating layer made of Sn or Sn alloy is virtually lost. As a result, the plating material does not exhibit its original performance.

  Such a problem can be solved by increasing the thickness of the surface plating layer made of Sn or Sn alloy and extending the disappearance time of the surface plating layer. However, such countermeasures are wasteful of resources. Moreover, not only that, but when the plating material is used for, for example, a connector (fitting type connector) that fits a large number of terminals at the same time, it causes a new problem that the assembly work to the mating material becomes difficult. There is also.

  By the way, in a fitting type connector, the male terminal and the female terminal are fitted and the electrical connection is taken. In recent years, with regard to connector terminals mounted on automobiles, transmission information has been increased in quantity and electronically controlled. As a result, the number of connector pins is increasing. In that case, if the insertion force of the terminal is the same as before, it is necessary to increase the insertion force of the connector by an amount corresponding to the increase in the number of pins. For this reason, there is a strong demand for reducing the insertion force of multi-polar connector pins.

  As a terminal that meets such a demand, for example, there is a terminal in which an Au plating layer is formed on the terminal surface. The insertion force when using the terminal is reduced. However, since Au is expensive, there is a problem that the manufactured terminals are expensive. In addition, as a connector terminal, what has Sn-plated on the surface of a conductive base material like Cu is generally used. In the case of this terminal, since Sn is an easily oxidizable material, a hard Sn oxide film is always formed on the surface in the atmosphere.

  And if this terminal is inserted, the above-mentioned hard Sn oxide film will be broken at the time of fitting with the counterpart material. Then, the unoxidized Sn plating layer located below and the mating material come into contact with each other, and electrical connection between them is realized. However, when the formed Sn plating layer is thin, the entire plating layer becomes an oxide film, so that the oxide film is hardly broken at the time of fitting. In addition, when the substrate is made of Cu or a Cu alloy, the Sn component of the thin Sn plating layer reacts with the substrate component during actual use in a high temperature environment, and the Cu component is exposed on the surface. In this case, an oxide film of Cu is formed. As a result, contact reliability with the counterpart material is lost.

  Such a problem can be made difficult to occur by thickening the Sn plating layer on the surface. However, in that case, there arises a new problem that the insertion force with the mating member becomes large at the time of fitting. For this reason, particularly in a high temperature environment, an expensive Au plated terminal can be used, or only a Sn plated terminal with a thin Sn plating layer on the surface and a small number of pins can be used. There was a problem.

  By the way, when forming the plating layer which consists of Sn or Sn alloy on the surface of a terminal, generally bright Sn plating and reflow Sn plating are applied. Among these, in the case of a plating layer formed by bright Sn plating, the plating layer contains a large amount of additive components used during the plating process. Further, the crystal grain size of the plated Sn becomes fine. Therefore, the lubricity of the plating layer surface is excellent, and the amount of abrasion during fitting and sliding is reduced. As a result, the pluggability at the time of fitting is excellent. However, since the crystal grain size is fine, when used in a high temperature environment, the diffusion rate of the base material component based on the grain boundary diffusion increases and the base material component may diffuse to the surface. . That is, the material for the bright Sn plating is inferior in heat resistance.

  On the other hand, in the case of reflow Sn plating, the surface plating layer is heated and melted after the entire plating process is completed. Therefore, in the formed reflow plating layer, the crystal grain size of the plating Sn is increased, and the additive component mixed during the plating process is also removed. Therefore, the diffusion rate based on the grain boundary diffusion of the base material component becomes small even in a high temperature environment. That is, the heat resistance of the material is improved. However, since the crystal grain size of the plated Sn is large, the amount of wear during fitting and sliding is large, and since there are few additive components, the lubricity is inferior and the insertion / extraction properties deteriorate.

  For these reasons, various methods have been proposed in order to improve the heat resistance and insertion / removability of the Sn plating layer. For example, JP-A-8-7940 and JP-A-4-329891 disclose a method of forming a plating layer of a refractory metal, particularly Ni, as a base of an Sn plating layer for the purpose of improving heat resistance. Has been. According to this method, when the temperature region is about 100 to 120 ° C., the Ni plating layer suppresses the reaction between the base component (alloy component such as Cu and Zn) and the Sn component of the Sn plating layer, And since the reaction rate of Ni and Sn is small, the heat-resistant effect is acquired. However, in a high temperature environment of 140 ° C. or higher, the reaction rate between Ni and Sn increases, and the surface Sn plating layer changes in quality, and the heat resistance effect cannot be obtained.

  Japanese Patent Application Laid-Open No. 11-121075 and Japanese Patent Application Laid-Open No. 10-302864 disclose methods for reducing the thickness of the Sn plating layer on the surface in order to improve the insertability. In the case of the surface Sn plating layer formed by this method, the amount of abrasion in the fitting / sliding property is reduced and the insertion / extraction property is improved. However, since the thickness of the Sn plating layer is thin, the Sn plating layer on the surface is alloyed and disappeared by diffusion with the base material even with a small thermal history, and the contact resistance with the counterpart material increases.

  Thus, in the case of the conventional plating material which formed Sn plating layer on the surface, there existed a problem that coexistence of the heat resistance and insertion / extraction property was very difficult.

  According to the present invention, in a plating material having a Sn or Sn alloy plating layer formed on the surface, the diffusion reaction is delayed between the plating layer and the base material or the base plating layer even under a high temperature environment. It is designed for the purpose of providing plating materials with good heat resistance, and also has good heat resistance as described above, as well as good insertability, and is a mating connector or contactor used in high-temperature environments. An object of the present invention is to provide a plating material suitable as a material.

  Furthermore, an object of the present invention is to provide a method for producing the above-described plating material, and an electric / electronic component using the plating material, such as a fitting connector and a contact.

  In order to achieve the above-described object, in the present invention, the surface of the conductive base material includes any of the periodic table group 4, group 5, group 6, group 7, group 8, group 9, or group 10. An underplating layer made of one kind of metal or an alloy containing the same as a main component, an intermediate plating layer made of Cu or Cu alloy, and a surface plating layer made of Sn or Sn alloy are formed in this order. A plating material characterized by the above is provided.

  In that case, the thickness of the base plating layer is 0.05 to 2 μm, and the thickness of the intermediate plating layer is preferably 0.01 to 1 μm, and the thickness of the surface plating layer is A plating material suitable for having a thickness of 1.9 times or more the thickness of the intermediate plating layer is provided. In the present invention, any one of the metals included in Group 4, Group 5, Group 6, Group 7, Group 8, Group 10, or Group 10 of the periodic table is formed on the surface of the conductive substrate. There is provided a method for producing a plating material, characterized by forming a base plating layer made of an alloy containing as a main component, an intermediate plating layer made of Cu or Cu alloy, and a surface plating layer made of Sn or Sn alloy in this order. Preferably, after the intermediate plating layer is formed, the Sn plating layer and at least one selected from the group consisting of Ag, Bi, Cu, In, Pb and Sb are formed on the intermediate plating layer. There is provided a method for producing a plating material in which a plating layer is formed in this order and then reflow treatment or thermal diffusion treatment is performed.

  Moreover, in this invention, the electrical / electronic component using the above-mentioned plating material, specifically, a fitting type connector and a contactor are provided.

  As apparent from the above description, the plating material of the present invention has an intermediate plating layer made of Cu or a Cu alloy interposed between the base plating layer and the surface plating layer, and the surface plating layer and the intermediate plating layer. Even if the thickness is in a high temperature environment, the surface plating layer Sn or Sn alloy is designed to remain.

  Therefore, this plating material has good heat resistance, and also has good heat resistance and insertion / extraction properties. For example, a connector disposed in a high temperature environment such as in an automobile engine room, a mating connector, It is useful as a material for various electric and electronic parts such as contacts.

  The plating material of the present invention has a four-layer structure as described later. And the constituent material and thickness of each layer are designed so that it may mention later in relation to the above-mentioned improvement of heat resistance, and improving heat resistance and insertion / extraction simultaneously. First, as shown in FIG. 1, the plating material of the present invention has a base plating layer 2, an intermediate plating layer 3, and a surface plating layer 4, which will be described later, in this order on the conductive substrate 1 as a whole. Is formed. In this plating material, the intermediate plating layer 3 is interposed between the base plating layer 2 and the surface plating layer 4, and the intermediate plating 3 exhibits a function described later, whereby the surface plating layer 4 disappears in a high temperature environment. It has the greatest feature where it is suppressed.

  First, the material of the conductive substrate 1 is not particularly limited. For example, in consideration of the use as a connection connector, depending on the required mechanical strength, heat resistance, and conductivity, for example, pure copper; phosphor bronze Copper alloy such as brass, white, beryllium copper and corson alloy; iron alloy such as pure iron and stainless steel; various nickel alloys; composite material such as Cu-coated Fe material and Ni-coated Fe material Should be selected.

  Of these materials, Cu or Cu alloy is preferred. When the conductive substrate 1 is not a Cu-based material, the adhesion and corrosion resistance of the plating film are further improved if the surface of the conductive substrate 1 is subjected to actual use after being plated with Cu or a Cu alloy. The base plating layer 2 formed on the conductive base material 1 is provided in order to ensure adhesion strength between the base material 1 and the surface plating layer, and the components of the base material thermally diffuse to the surface layer side. It also functions as a barrier layer to prevent this. Specifically, Group 4 elements (Ti, Zr, Hf), Group 5 elements (V, Nb, Ta), Group 6 elements (Cr, Mo, W), Group 7 elements (Mn, Tc, Re) ), Group 8 element (Fe, Ru, Os), Group 9 element (Co, Rh, Ir), Group 10 element (Ni, Pd, Pt), or an alloy mainly composed thereof. Yes.

  These metals are all high melting point metals having a melting point of 1000 ° C. or higher. For example, since the operating environment temperature of the connector is generally 200 ° C. or lower, it is a matter of course that the base plating layer 2 is less likely to cause thermal diffusion in such an operating environment. Effectively prevents heat diffusion to Of the metals described above, Ni, Co, and Fe are preferred because of their cost and ease of plating. And as an alloy which has them as a main component, Ni-P, Ni-Sn, Co-P, Ni-Co, Ni-Co-P, Ni-Cu, Ni-Cr, Ni-Zn, Ni- Fe etc. can be mentioned.

  In addition, although the above-described underplating layer can be formed by a plating method such as a PVD method, it is preferable to apply a wet plating method. Here, when the main purpose is to improve the heat resistance of the plating material, the thickness of the underlying plating layer 2 is preferably set in the range of 0.05 to 2 μm. This is because if the thickness of the underlying plating layer 2 is too thin, the above-described effects are not sufficiently exerted, and if it is too thick, the plating distortion increases and the substrate 1 is easily peeled off.

  Moreover, when the improvement of the heat resistance of a plating material and the improvement of insertion / extraction are intended, the thickness of the base plating layer 2 is not particularly limited, but the above-described diffusion prevention effect on the surface layer side of the base material component is not limited. In order to exhibit it, what is necessary is just 0.25 micrometer or more. However, not only is it meaningless to make it too thick, but there is also a case where processing cracks occur during processing to the terminal, so the upper limit of the thickness is generally in the range of 0.5 to 2 μm in consideration of workability. Should be set.

  Next, the intermediate plating layer 3 formed on the base plating layer 2 is made of Cu or a Cu alloy. And this intermediate plating layer 3 functions as a layer which prevents the component of the foundation | substrate plating layer 2 and the Sn component of the surface plating layer 4 from mutually diffusing by the aspect mentioned later. The reaction rate between the Cu component and the Sn component of the surface plating layer 4 is higher than the reaction rate between the Cu component of the intermediate plating layer 3 and the component of the base plating layer 2 (the above-described metal or alloy thereof). Therefore, when this plating material is exposed to a high temperature environment, the thermal diffusion of the Sn component of the surface plating layer 4 to the intermediate plating layer 3 proceeds, and as a result, the intermediate plating layer 3 is as shown in FIG. Then, it is converted into a layer 3 ′ made of an Sn—Cu intermetallic compound. At the same time, the Sn component of the surface plating layer 4 of the plating material diffuses and moves toward the intermediate plating layer 3 from the interface with the intermediate plating layer 3 and is converted into the intermetallic compound. As a result, the thickness of the plating layer 4 ′, which is a layer in which Sn (or Sn alloy) remains, is reduced. When the Cu component of the intermediate plating layer 3 has received Sn or Sn alloy diffusing from the upper layer side, interdiffusion between Sn or Sn alloy and Cu or Cu alloy stops.

  As a result, as shown in FIG. 2, a part of the intermediate plating layer 3 and the surface plating layer 4 in FIG. 1 becomes a layer 3 'made of an intermetallic compound. Further, the surface plating layer 4 of FIG. 1 is thin, but remains as a layer 4 ′ made of Sn or Sn alloy. As described above, the intermetallic compound layer 3 ′ is interposed between the base plating layer 2 and the layer 4 ′ made of Sn or Sn alloy, thereby suppressing the reaction between the layer 4 ′ and the base plating layer 2. Will be.

Therefore, in the case of this plating material, the layer structure shown in FIG. 2 is used in a high-temperature environment, that is, the mutual diffusion of Sn or Sn alloy and Cu or Cu alloy is suppressed. Become. Therefore, the surface plating layer made of Sn or Sn alloy is not lost during the use process. Cu ₆ Sn ₅ and Cu ₃ Sn are well known as Sn—Cu intermetallic compounds. In the case of Cu ₆ Sn ₅ , it is a compound produced by reacting 1.9 volumes of Sn with 1 volume of Cu. Cu ₃ Sn is a compound formed by reacting 0.8 volume of Sn with 1 volume of Cu.

  Therefore, if the thickness of the surface plating layer 4 is 1.9 times or more of the thickness of the intermediate plating layer 3, all of the Cu components of the intermediate plating layer 3 are formed by the above-described mutual diffusion. Even if it is converted to, the surface plating layer 4 'made of Sn or Sn alloy still remains. And the Cu component of the intermediate | middle plating layer 3 is fixed as a Sn-Cu intermetallic compound, and the thermal diffusion is suppressed.

  For this reason, in the plating material of the present invention, it is preferable to design the thickness of the surface plating layer 4 to a value of 1.9 times or more the thickness of the intermediate plating layer 3. By doing in this way, even if the plating material is in a high temperature environment, the surface plating layer 4 ′ is always Sn or Sn alloy, so that the contact reliability is ensured.

  In that case, if the thickness of the intermediate plating layer 3 is made too thin, for example, when the intermediate plating layer 3 is made of Cu, a large number of fine holes exist in the layer. Therefore, the Ni component, Cu component, etc. of the base plating layer 2 diffuse into the intermediate plating layer through the fine holes. Further, if the thickness of the intermediate plating layer 3 is excessively increased, the Sn and Sn alloy are all consumed by the above-described mutual diffusion unless the thickness of the surface plating layer 4 is significantly increased. Or Sn alloy will not remain. In order to avoid this, if the surface plating layer 4 is made thick, it will increase its insertion resistance when the material is used with a mating connector.

  For this reason, the thickness of the intermediate plating layer 3 is preferably set in the range of 0.01 to 1.0 μm. Examples of the Cu alloy used for forming the intermediate plating layer 3 include Cu—Zn, Cu—Sn, Cu—Ni, and Cu—Ni—Sn. In that case, the amount of the Cu component needs to be an amount that does not inhibit the formation of the above-described Cu—Sn-based intermetallic compound, and may be a value of, for example, 50% by mass or more.

  In the case of the plating material of the present invention, with respect to the thickness of the intermediate plating layer 3 and the surface plating layer 4, the above-described relationship, that is, the relationship in which the latter thickness is set to 1.9 times or more of the former thickness is maintained. In the state, the thickness of the surface plating layer 4 can be reduced. As a result, the insertability can be improved. For example, if the thickness of the intermediate plating layer 3 is 0.49 [mu] m or less, even if the thickness of the surface plating layer in the plating material is 1 [mu] m or less, good insertability can be exhibited with sufficient heat resistance. it can. Further, if the thickness of the intermediate plating layer 3 is 0.3 μm or less, it is preferable that the thickness of the surface plating layer 4 can be set to about 0.6 μm.

  As already described, the surface plating layer 4 is formed of Sn or an Sn alloy, and is provided to ensure electrical contact characteristics, corrosion resistance, and solderability as a plating material. In particular, the Sn alloy is preferable because it can further improve the insertability. As a Sn alloy in that case, for example, an alloy containing one or more of Ag, Bi, Cu, In, Pb, and Sb in Sn is a preferable example. This is because these Sn alloys all have good solderability and do not generate whiskers when the surface plating layer is formed.

  In addition, since the outflow to the environment becomes a problem, it is better to avoid the use of Sn alloy containing Pb as much as possible. This Sn alloy plating layer can be formed using a predetermined alloy plating bath, but it is preferable to form the Sn alloy plating layer by the following method because the manufacturing cost can be greatly reduced.

  That is, after forming a base plating layer and an intermediate plating layer on a substrate, an Sn plating layer and a plating layer of one or more metals of Ag, Bi, Cu, In, Pb, and Sb are further formed. Laminate in this order. The Sn plating layer described above may be a Sn alloy plating layer. Next, a reflow process or a thermal diffusion process is performed on the entire laminate, and selective thermal diffusion is performed between the metal of the metal plating layer and the Sn of the Sn layer (or Sn alloy plating layer). Both are alloyed. For example, in the case of the reflow process, the reflow process for 5 seconds or less is performed at an actual temperature of 230 to 300 ° C., and in the case of the thermal diffusion process, the process may be performed at a temperature of 100 to 120 ° C. for several hours. This is because heat diffusion between other layers hardly occurs at such a temperature.

  In the plating material of the present invention, the thickness of each plating layer is smaller than the thickness of each plating layer, between the substrate and the base plating layer, between the base plating layer and the intermediate plating layer, or between the intermediate plating layer and the surface plating layer. A plating layer of material may be interposed. Moreover, as a raw material shape, any of shapes, such as a strip, a round wire, and a square wire, may be sufficient.

(Example)
Examples 1-4, Reference Examples 1-29, Comparative Examples 1-25
After electrolytic degreasing and pickling were sequentially performed on the brass strip, a base plating layer, an intermediate plating layer, and a surface plating layer were sequentially formed, and various plating materials shown in Tables 2 and 3 were manufactured. The plating conditions at the time of forming each layer are as shown in Table 1.

Each manufactured plating material was heated to the temperature shown in Table 2 and Table 3, and the remaining thickness of the surface plating layer at that time was measured with the following specifications. The initial dynamic friction coefficient was measured according to the following specifications. Residual thickness: measured by the constant current dissolution method after leaving the plating material in an air bath at a temperature of 100 to 160 ° C. for 120 hours.
Coefficient of dynamic friction: Measured using a Bowden friction tester under the conditions of a load of 2.94 N, a sliding distance of 10 mm, a sliding speed of 100 mm / min, and a sliding frequency of once. As the mating material, a brass strip having a thickness of 0.25 mm was subjected to reflow Sn plating of 1 μm and then subjected to an extension process to 0.5 mmR.
The following results are collectively shown in Tables 2 and 3.

From Table 2 and Table 3, it is clear from the following.
(1) Comparing the example and the comparative example, the surface plating layer (Sn) remains in the example as a whole even when the environmental temperature becomes high, and the dynamic friction coefficient is small. Further, in the example in which the thickness of the formed surface plating layer is thicker, the remaining thickness of the surface plating layer (Sn) after heating is thicker and heat resistance is maintained. However, on the other hand, the dynamic friction coefficient is smaller in the embodiment where the thickness of the surface plating layer is thin. For this reason, the thinner surface plating layer is more advantageous in terms of insertability.

(2) As in Reference Examples 7 to 10, even if the underlying plating layer is other than the Ni layer, it can prevent diffusion of the base material component (alloy component such as Cu or Zn) on the surface layer side. Similar effects are obtained. Moreover, the same effect is acquired even when the reaction rate with respect to the surface plating layer is larger than the reaction rate with respect to the base plating layer of the intermediate plating layer as in Reference Examples 6 to 11.
(3) When the example and the comparative example are compared with respect to the case where the surface plating layer is subjected to the reflow treatment, the dynamic friction coefficient in the comparative example 6 is 0.38, whereas the dynamic friction coefficient in each of the examples 1, 2, and 3 is 0.22 or less. (Table 3). It can be seen that the coefficient of dynamic friction decreases when the Sn plating layer and the plating layer composed of at least one layer containing Ag or In are reflowed to form an Sn alloy.

  As in the case of Reference Example 13, when the thickness of the intermediate plating layer is thin, the effect of suppressing the diffusion of the base plating layer and the surface plating layer is small. As apparent from the comparison between Reference Example 14 and Reference Example 15, when the surface plating layer is thick, the heat resistance is improved, and when it is thin, the dynamic friction coefficient is reduced and the insertion / extraction is improved.

  From each sample of Reference Example 3, Reference Example 5, Reference Example 12, Comparative Example 5, and Comparative Example 6, a male terminal and a female terminal having a tab width of 2.3 mm were manufactured. These male terminals and female terminals are combined and fitted as shown in Table 4, and then subjected to heat treatment at a temperature of 160 ° C. for 120 hours, the contact resistance between the terminals in each member is determined. It was measured. The insertion at the time of fitting was performed at an insertion force speed of 2 mm / sec, and the peak strength at the time of insertion was measured as the insertion force. The average value of n = 5 was determined, and the results are shown in Table 4.

  The contact resistance was measured by soldering a lead to a terminal and passing a current of 10 mA. The average value of n = 10 was determined, and the results are shown in Table 4.

From Table 4, the following is clear.
(1) When comparing the reference example and the comparative example, in the case of the reference example, the insertion force during fitting is low as a whole, and the contact resistance after heat treatment is low. Moreover, the insertion force at the time of fitting in each reference example and each comparative example is a low value of about 5.3 to 6.5 N. And the direction which uses the thing of a reference example for a male terminal has a low insertion force compared with the case where it uses for a female terminal. This is because at the time of fitting, the female terminal side is in a point contact state and the point that can be cut becomes one point, but the male terminal side contacts in a linear manner, so the portion to be cut becomes linear. it is conceivable that.

  Therefore, when aiming at a low insertion force, it is considered effective to reduce the thickness of the surface plating layer (Sn) on the male terminal side. Further, in the reference example, the reason why the contact resistance after the heat treatment is low is that the contact reliability of the reference example terminal of the present invention is improved due to the remaining surface plating layer (Sn) even after the heat treatment. It is thought that. On the other hand, when the comparative terminal is used, the surface plating layer (Sn) disappears due to the heat treatment and the contact resistance becomes high.

It is sectional drawing which shows one example of the plating material of this invention. It is sectional drawing which shows a layer structure when the plating material of FIG. 1 is exposed to a high temperature environment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Conductive base material 2 Underlying plating layer 3 Intermediate plating layer 3 ′ Interdiffusion layer of Sn and Cu 4 Surface plating layer 4 ′ Sn remaining plating layer

Claims (9)

A base plating layer made of any one metal included in Group 4, Group 5, Group 6, Group 7, Group 8, Group 8, Group 10 of the periodic table, or an alloy thereof on the surface of the conductive substrate When,
An intermediate plating layer made of Cu or Cu alloy ;
A front surface plating layer is formed in this order,
The surface plated layer, and characterized by comprising a Sn plating layer, Ag or an alloy layer in which the both are alloyed both selective thermal diffusion is performed with I n or al made the metal plating layer Plating material for electrical and electronic parts .   The plating material according to claim 1, wherein the base plating layer is made of any one metal of Ni, Co, or Fe, or an alloy of the metal.   2. The plating material according to claim 1, wherein the thickness of the base plating layer is 0.05 to 2 μm, and the thickness of the intermediate plating layer is 0.01 to 1 μm. The plating material according to claim 3 , wherein the intermediate plating layer has a thickness of 0.05 to 0.49 μm.   The plating material according to claim 1, wherein the surface plating layer has a thickness of 1 μm or less. The plating material according to claim 1 , wherein the conductive substrate is made of Cu or a Cu alloy. An electric / electronic component comprising the plating material according to any one of claims 1 to 6 .   The electrical / electronic component according to claim 7, wherein the electrical / electronic component is a fitting connector or a contact. A base plating layer made of any one metal included in Group 4, Group 5, Group 6, Group 7, Group 8, Group 8, Group 10 of the periodic table, or an alloy thereof on the surface of the conductive substrate Form the
Next, an intermediate plating layer made of Cu or Cu alloy is formed,
Wherein on the intermediate plated layer, the more Sn plating layer and Ag or I n or al made the metal plating layer formed in this order, subjected to selective thermal diffusion between the Sn plated layer and the metal plating layer, A method for producing a plating material for electrical and electronic parts, comprising forming a surface plating layer by alloying the two .