JP2008269999A - Terminal for coupling connector and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a terminal for coupling connector having a terminal coupling portion and a soldered portion in which a low friction coefficient in the terminal coupling portion is realized and a soldering property of the soldered portion is improved, and provide its manufacturing method. <P>SOLUTION: A copper alloy sheet is blanked to form a terminal raw material and a terminal coupling portion 5 of the raw material undergoes a pressing process to increase a surface roughness of the terminal coupling portion 5, and then a whole of the copper alloy sheet is Ni-plated, Cu-plated and Sn-plated additionally. Subsequently, a reflowing process is conducted to form a Cu-Sn alloy layer 12 from the Cu-plated layer and the Sn-plated layer and the Sn-plated layer 13 is smoothed. Thus, the terminal coupling portion 5 has a hard Cu-Sn alloy layer partly exposed to reduce a friction coefficient. The soldered portion has no exposure of the Cu-Su alloy layer 12 and is covered by the Sn layer 13a to improve a soldering property. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a fitting connector terminal having a terminal fitting portion and a soldering portion, and a method for manufacturing the same.

  Patent Document 1 describes a conductive material for connection parts that has high electrical reliability (low contact resistance), a low coefficient of friction, and is suitable as a fitting connector terminal. In the invention of Patent Document 1, a copper alloy strip having a surface roughness larger than that of a normal copper alloy strip is used as a base material, and a Ni plating layer, a Cu plating layer, and a Sn plating layer are formed on the base material surface in this order, or Cu plating layer and Sn plating layer are formed in this order or only the Sn plating layer is formed, and the Sn plating layer is reflow-treated to form Cu-- from the Cu plating layer and the Sn plating layer, or from the copper alloy base material and the Sn plating layer. A part of the Cu-Sn alloy layer is exposed to the surface from between the Sn plating layer smoothed by the reflow process while forming the Sn alloy layer (Cu-Sn at the convex and concave portions formed on the surface of the base material) Part of the alloy layer is exposed).

  The conductive material for connecting parts formed after the reflow process in Patent Document 1 has a Cu—Sn alloy layer and a Sn layer, or a Ni layer, a Cu—Sn alloy layer, and a Sn layer in this order as a surface coating layer. Depending on the case, the Cu layer remains between the surface of the base material and the Cu—Sn alloy layer or between the Ni layer and the Cu—Sn alloy layer. In Patent Document 1, the surface exposed area ratio of the Cu—Sn alloy layer is 3 to 75%, the average thickness is 0.1 to 3.0 μm, the Cu content is 20 to 70 at%, and the average thickness of the Sn layer. Is preferably 0.2 to 5.0 μm, the arithmetic average roughness Ra in at least one direction is preferably 0.15 μm or more and the arithmetic average roughness Ra in all directions is preferably 4.0 μm or less on the surface of the base material. It is described that the surface exposure interval of the Sn alloy layer is preferably 0.01 to 0.5 mm in at least one direction.

Patent Document 2 describes a conductive material for connecting parts corresponding to the subordinate concept of Patent Document 1 and a method for manufacturing the same. The plating layer configuration and the coating layer configuration itself after the reflow treatment are the same as those in Patent Document 1.
In the conductive material for connecting parts formed after the reflow process in Patent Document 2, the surface exposed area ratio of the Cu—Sn alloy layer in the surface coating layer is 3 to 75%, and the average thickness is 0.2 to 3.0 μm. The Cu content is 20 to 70 at%, the average thickness of the Sn layer is 0.2 to 5.0 μm, the arithmetic average roughness Ra in at least one direction of the material surface is 0.15 μm or more, and the arithmetic average in all directions The roughness Ra is defined as 3.0 μm or less, the arithmetic average roughness Ra in at least one direction on the base material surface is 0.3 μm or more, and the arithmetic average roughness Ra in all directions is preferably 4.0 μm or less. It is described that the surface exposure interval of the Cu—Sn alloy layer is preferably 0.01 to 0.5 mm in at least one direction.

Furthermore, the present applicant has applied for a patent for an invention relating to a conductive material for connecting parts, which basically inherits the technical ideas of Patent Documents 1 and 2 and has improved solderability (Japanese Patent Application No. 2007-22206). In this application, the plating layer structure and the coating layer structure itself after the reflow treatment are basically the same as those of Patent Documents 1 and 2, but this application is different from Patent Documents 1 and 2, and the Cu—Sn alloy layer. May not be exposed.
In the conductive material for connecting parts formed after the reflow treatment in this application, the average thickness of the Ni layer of the surface coating layer is 3.0 μm or less, and the average thickness of the Cu—Sn alloy layer is 0.2 to 3 0.0 μm, diameter of the smallest inscribed circle [D1] of the Sn layer in the vertical section of the material is 0.2 μm or less, diameter [D2] of the largest inscribed circle is 1.2 to 20 μm, the outermost point of the material and Cu− When the altitude difference [Y] from the outermost point of the Sn alloy layer is specified to be 0.2 μm or less and [D1] is 0 μm (when the Cu—Sn alloy layer is partially exposed), It is described that the maximum inscribed circle diameter [D3] of the Cu—Sn alloy layer is preferably 150 μm or less and / or the maximum inscribed circle diameter [D4] of the Sn layer on the material surface is preferably 300 μm or less.

  On the other hand, in Patent Documents 3 to 5, after performing a punching process on a copper alloy strip, a Sn plating layer is formed on the punching end surface by applying Sn plating to the whole, so-called post plating, and punching process. It is described that the solderability of terminals and the like is improved as compared with the case where the Sn plating is applied to the copper alloy sheet before (1).

JP 2006-77307 A JP 2006-183068 A JP 2004-3000524 A JP 2005-105307 A JP 2005-183298 A

The conductive materials for connecting parts described in Patent Documents 1 and 2 are based on the fact that the outermost layer has an Sn layer and the surface roughness of the base material surface is increased. Partly exposed on the surface of the material (particularly, the Cu-Sn alloy layer protrudes in Patent Document 2), so that the electrical reliability is high and the coefficient of friction is small, and it is suitable as a fitting connector terminal. . However, since the Cu—Sn alloy layer is partially exposed on the surface of the material, the solderability is inferior compared to the material whose entire surface is covered with the Sn plating layer.
In the conductive material for connecting parts described in Japanese Patent Application No. 2007-22206, the Sn layer is formed relatively thick in the concave and convex portions on the surface of the base material. Has been improved. However, based on the fact that the surface roughness of the base material surface is increased as in Patent Documents 1 and 2, the Cu—Sn alloy layer is partially exposed at the uneven portions of the base material surface, or the Sn layer is The solderability is slightly inferior to that of a material that is extremely thin and whose surface is covered with an Sn plating layer having a substantially uniform thickness.

On the other hand, for example, a fitting type terminal having a soldered portion such as a pin terminal used for a printed wiring board is required to have a low coefficient of friction so that the terminal can be fitted with a low insertion force in the terminal fitting portion. At the same time, excellent solderability is required at the soldering portion.
In order to achieve a low friction coefficient in the terminal fitting portion, it is desirable to use materials described in Patent Documents 1 and 2 and Japanese Patent Application No. 2007-22206. However, these materials have some problems in solderability as described above. As described in Patent Documents 3 to 5, the solderability is improved by performing post-plating, but it goes without saying that the improvement is not essential by itself.

  The present invention has been made in view of the above-described problems of the prior art, and is described in Patent Documents 1 and 2 and Japanese Patent Application No. 2007-22206 regarding a fitting connector terminal having a terminal fitting portion and a soldering portion. An object of the present invention is to realize a low coefficient of friction in the terminal fitting portion based on the technical idea of the invention (point of increasing the surface roughness of the base material surface) and at the same time to improve the solderability of the soldering portion. .

  The fitting connector terminal according to the present invention is a fitting connector terminal manufactured by post-plating and reflow treatment on a punched copper alloy sheet (plate or strip), and the terminal fitting portion and the solder A surface fitting layer having a surface roughness larger than that of the soldered portion, a Cu—Sn alloy layer and a Sn layer being formed in this order as a surface coating layer, and the Sn layer. Is smoothed by reflow processing. Since post-plating is performed, the plating layer is formed not only on the base material plate surface but also on the punched end surface. In the terminal fitting portion, the surface roughness of the base plate is at least an arithmetic average roughness Ra in one direction of 0.15 μm or more and an arithmetic average roughness Ra in all directions within a range of 4.0 μm or less. It is desirable to be. The plating layer is usually formed along the unevenness of the plate surface reflecting the surface form (surface roughness) of the base material, but the Sn plating layer is melted and flowed by the reflow process, and is in a state along the initial unevenness. Is smoothed.

Since the fitting connector terminal according to the present invention is post-plated, not only the surface of the copper alloy sheet (base material) but also the surface coating layer (Cu-Sn alloy layer) on the punched end surface. Sn layer) is formed.
The fitting connector terminal according to the present invention may further have a Ni layer formed as a surface coating layer. In this case, the Ni layer, the Cu—Sn alloy layer, and the Sn layer are formed in this order on the surface of the base material. When the Ni layer is formed, a base Cu layer may be formed as a base for the Ni layer.
When there is no Ni layer, it may have a Cu layer between the base material surface and the Cu-Sn alloy layer. When there is a Ni layer, it has a Cu layer between the Ni layer and the Cu-Sn alloy layer. It may be.

  The terminal for fitting type connectors according to the present invention includes a case where a part of the Cu—Sn alloy layer is exposed on the plate surface of the terminal fitting portion. The exposure of the Cu—Sn alloy layer in the presence of the Sn plating layer has a large surface roughness of the base metal plate surface as described in Patent Documents 1 and 2, and the Sn plating layer flows by reflow treatment. Caused by smoothing. Even when the Cu—Sn alloy layer is exposed on the surface of the terminal fitting portion plate, it is desirable that the Cu—Sn alloy layer is not exposed in the soldered portion, and the Sn layer covers the entire surface. This is easily achieved because the surface roughness of the soldered portion plate surface is smaller than that of the terminal fitting portion. After the reflow treatment, an Sn plating layer can be further formed to cover the entire surface with the Sn layer.

  The manufacturing method of the fitting connector terminal according to the present invention forms a copper alloy sheet in which the copper alloy sheet is subjected to punching and the terminal material is connected in a chain in the length direction via a strip-shaped connecting part. At the same time as the punching process or before or after the punching process, the copper alloy sheet strip is pressed to increase the surface roughness of the terminal material plate surface (base material plate surface) at the terminal fitting portion. Thereafter, the copper alloy sheet is post-plated to form a Cu plating layer and an Sn plating layer in this order, and then the Sn plating layer is reflowed to form a Cu-Sn alloy layer from the Cu plating layer and the Sn plating layer. And the Sn plating layer is smoothed. Since post-plating is performed on the copper alloy strip, the plating layer is formed not only on the terminal material plate surface (base material plate surface) but also on the punched end surface. In the terminal fitting portion, the surface roughness of the terminal material plate surface is within the range where the arithmetic average roughness Ra in at least one direction is 0.15 μm or more and the arithmetic average roughness Ra in all directions is 4.0 μm or less. It is desirable to do.

If necessary, a Ni plating layer can be formed under the Cu plating layer. When forming the Ni plating layer, a base Cu plating layer known per se may be formed under the Ni plating layer. Whether or not the Ni plating layer is formed, the Cu plating layer that is not consumed due to the formation of the Cu—Sn alloy layer remains as the Cu layer.
It is also possible to form a Cu-Sn alloy layer from the copper alloy base material and the Sn plating layer by forming only the Sn plating layer on the copper alloy strip and performing a reflow treatment.

The said manufacturing method includes the case where a part of Cu-Sn alloy layer is exposed in the said terminal fitting part board surface by a reflow process. However, even in that case, it is desirable to cover the entire surface of the Sn layer without exposing the Cu—Sn alloy layer on the surface of the soldering portion. It is easily achieved because it is small compared to the case (in the case of a general copper alloy strip, the Sn layer is formed when the Cu—Sn alloy layer is exposed unless the surface roughness is increased. Is completely or almost extinguished). When a part of the Cu—Sn alloy layer is exposed on the surface of the terminal fitting portion, Sn plating may be further performed.
In addition, instead of performing the said press work, a rolling process can be performed and the surface roughness of the terminal raw material board surface of a terminal fitting part can also be increased from others.

According to the present invention, the surface roughness of the base material is increased in the terminal fitting portion (desirably, the arithmetic average roughness Ra in at least one direction is 0.15 μm or more and the arithmetic average roughness in all directions is Ra is 4.0 μm or less), even if the Cu—Sn alloy layer is partly exposed in the convex and concave portions of the base material plate surface, or the Sn layer is extremely thin in the same portion, even if the average thickness is the same A low friction coefficient is realized in the terminal fitting portion as compared with a normal material whose entire surface is coated with a Sn plating layer having a substantially uniform thickness. In addition, the surface of the base metal plate surface is as small as a normal copper alloy strip (generally, the arithmetic average roughness in all directions is less than 0.15 μm). The solderability is excellent.
As described above, according to the present invention, in the fitting connector terminal having the terminal fitting portion and the soldering portion, a low friction coefficient is realized in the terminal fitting portion, and at the same time, the solderability of the soldering portion is improved. can do.

Hereinafter, with reference to the schematic diagrams of FIGS. 1 to 6, the fitting connector terminal according to the present invention and the manufacturing method thereof will be described.
This fitting connector terminal (here, a pin terminal used for a printed wiring board is assumed) is manufactured in the following process.
(1) As shown in FIG. 1, the normally rolled copper alloy strip 1 is punched in a forward feed process. As a result, the copper alloy strip 1 has the terminal material 2 connected in a chain form in the length direction via the strip-shaped connecting portion 3. Reference numeral 4 denotes a punched hole.
Simultaneously with this punching process, the terminal fitting portion 5 of the terminal material 2 is pressed to increase the surface roughness of the plate surface of the terminal fitting portion 5. A state in which the surface roughness is increased is indicated by small dots. The surface roughness of the soldering part 6 is the same as the original copper alloy strip. This press work can also be performed before the punching process (see FIG. 2) or after the punching process (see FIG. 3) in the sequential feed process.

(2) Post-plating is performed on the entire surface of the copper alloy strip 1. In this example, Ni plating, Cu plating, and Sn plating are performed. The entire surface of the terminal material 2 (including both the terminal fitting portion 5 and the soldering portion 6) is uniformly plated, and the average thickness of the Ni plating layer, the Cu plating layer, and the Sn plating layer is the terminal fitting. The joint portion 5 and the soldering portion 6 are basically the same.
(3) Subsequently, reflow processing is performed. The average thicknesses of the Ni layer, Cu layer (if remaining), Cu—Sn alloy layer, and Sn layer after the reflow treatment are basically the same in the terminal fitting portion 5 and the soldering portion 6.
(4) Thin Sn plating (flash plating) is performed as necessary.
(5) After forming the terminal material 2 as necessary, the terminal material 2 is separated from the connecting portion 3.

FIG. 4 schematically shows a cross-sectional view of the terminal material 2 obtained when Ni plating, Cu plating, and Sn plating are performed, followed by reflow processing ((a) is a terminal fitting portion, and (b) is a soldering portion). Indicate. In this example, a Cu—Sn alloy layer is formed from the Cu plating layer and the Sn plating layer by the reflow process, and the Cu plating layer disappears. Note that the Cu—Sn alloy layer formed between the Cu plating layer and the molten Sn plating layer usually grows reflecting the surface form of the base material.
When the terminal fitting portion 5 is viewed, the plate surface 8 of the base material 7 has a large surface roughness and unevenness, and a Ni layer 11, a Cu—Sn alloy layer 12, and a Sn layer 13 are formed as a surface coating layer. . The Ni layer 11 and the Cu—Sn alloy layer 12 are formed along the unevenness of the base material plate surface 8, and the Sn layer 13 is melted and smoothed by the reflow process, and the unevenness formed on the base material plate surface 8. The Cu—Sn alloy layer 12 is exposed at the convex portion. Since it is post-plating, the Ni layer 11, the Cu—Sn alloy layer 12 and the Sn layer 13 are also formed on the punched end face 9 of the base material 7.

On the other hand, when the soldering portion 6 is seen, the Ni layer 11, the Cu—Sn alloy layer 12 and the Sn layer 13 are formed as the surface covering layer as with the terminal fitting portion 5. Therefore, the Cu—Sn alloy layer 12 is not exposed on the surface, and the Sn layer 13 covers the entire surface. Similarly, a Ni layer 11, a Cu—Sn alloy layer 12, and a Sn layer 13 are formed on the punched end face 9.
The fitting connector terminal obtained from the terminal material 2 has the Sn layer 13 as the outermost layer on the plate surface of the terminal fitting portion 5 and the Cu-Sn alloy layer 12 having high hardness partially on the material surface. Since it is exposed, the electrical reliability is high and the friction coefficient is small, and since the Sn layer 13 covers the entire surface of the plate surface and the punched end surface in the soldering portion 6, the solderability is excellent. .

  FIG. 5 schematically shows a cross-sectional view of another terminal material obtained when Ni plating, Cu plating, and Sn plating are performed, followed by reflow treatment ((a) is a terminal fitting portion, and (b) is a soldering portion). Indicate. Also in this example, the Cu-Sn alloy layer is formed from the Cu plating layer and the Sn plating layer by the reflow process, and the Cu plating layer disappears. In addition, the same number is provided to the substantially same location as sectional drawing shown in FIG.

The example shown in FIG. 5 differs from the cross-sectional view shown in FIG. 4 only in that the Cu—Sn alloy layer 12 is not exposed from between the Sn layers 13 on the plate surface of the terminal fitting portion 5. However, the Cu—Sn alloy layer 12 has unevenness along the unevenness of the base material plate surface 8, and the thickness of the Sn layer 13 is considerably thinner than the average thickness in the terminal fitting portion 5. On the other hand, the soldering portion 7 is the same as the sectional view shown in FIG. 4, and the entire surface of the plate surface and the punched end surface is covered with the Sn layer 13 having a substantially uniform thickness.
The fitting connector terminal obtained from the terminal material 2 has a Sn13 layer as the outermost layer on the plate surface of the terminal fitting portion 5, and the Cu—Sn alloy layer is along the unevenness of the base material plate surface 8. Since the Sn layer 13 is thin and the Cu-Sn alloy layer 12 having high hardness is present in the vicinity of the material surface at the convex portion, the electrical reliability is high and the friction coefficient is small at the same time. Since the Sn layer 13 covers the entire surface of the soldered portion 6 on the plate surface and the punched end surface more thickly than the convex portion, the solderability is excellent.

FIG. 6 is a cross-sectional view of still another terminal material obtained when Ni plating, Cu plating and Sn plating are performed, followed by reflow treatment and further Sn plating is performed ((a) is a terminal fitting portion, ( b) schematically shows a soldering part). In this example, a Cu—Sn alloy layer is formed from the Cu plating layer and the Sn plating layer by the reflow process, and the Cu plating layer disappears. In addition, the same number is provided to the substantially same location as what is shown in FIG.
As shown in FIG. 6, in the terminal fitting part 5 and the soldering part 6, the base material 7, the Ni layer 11, the Cu—Sn alloy layer 12 and the Sn layer 13 are the same as those shown in FIG. An Sn layer 14 (Sn plating layer formed after the reflow process) is further formed thereon to cover the entire surface of the terminal fitting portion 5. On the plate surface of the terminal fitting portion 5, the Sn layer 14 covers the entire surface of the Cu—Sn alloy layer 12 and the Sn layer 13 exposed after the reflow process substantially evenly.

  The fitting connector terminal obtained from the terminal material 2 has a Sn layer (Sn layers 13 and 14) formed on the plate surface of the terminal fitting portion 5 and a Cu-Sn alloy layer formed on the base material plate surface 8. Since the Sn-layer (Sn layer 14) is relatively thin and the Cu-Sn alloy layer 12 having high hardness exists in the vicinity of the material surface, the electrical reliability The friction coefficient is small at the same time, and the Sn layer (Sn layers 13 and 14) covers the entire surface of the plate and the punched end surface of the soldering portion 6 thicker than the convex portion. Excellent. Note that the boundary between the Sn layers (Sn layers 13 and 14) cannot actually be distinguished.

In addition, in the terminal fitting part 5 and the soldering part 6 shown in FIGS. 4-6, when Cu plating layer remains after a reflow process, Cu layer is between the Ni layer 11 and the Cu-Sn alloy layer 12. Exists. In the case of performing the underlying Cu plating of Ni plating, the underlying Cu layer exists under the Ni layer 12. When Ni plating is not performed, the surface coating layers are the Cu—Sn alloy layer 12 and the Sn layer 13, and when the Cu plating layer remains after the reflow treatment, the base material 7 and the Cu—Sn alloy layer 12 are formed. There is a Cu layer in between.
Moreover, in the said terminal fitting part 5, although the surface roughness of both the plate | board surfaces of a copper alloy strip (base material 7) was increased by press work, it is only increased on one side (the other side is not increased). There may be.

  In the terminal fitting part 5 shown to Fig.4 (a), the surface roughness of the board surface of the base material 7 and the specific structure of the surface coating layer were described in patent document 1, 2 and Japanese Patent Application No. 2007-22206. It is desirable to make it the same as the conductive material for connecting parts, and the specific configuration of the surface coating layer can be obtained by using the manufacturing methods described in these documents. On the other hand, in the soldering portion 6 shown in FIG. 4B, the plate surface of the base material 7 has a surface roughness smaller than that of the terminal fitting portion, specifically, the surface roughness (generally all of the normal copper alloy strip). The average surface roughness Ra in the direction of (1) is less than 0.15 μm), and the surface coating layer configuration is a normal one (a state where each layer including the Sn layer is formed with a substantially uniform thickness). That's fine.

  In the terminal fitting portion 5 shown in FIGS. 5A and 6A, the surface roughness of the plate surface of the base material 7 and the specific configuration of the surface coating layer are described in Japanese Patent Application No. 2007-22206. It is desirable to make it the same as the conductive material for connecting parts, and the specific configuration of the surface coating layer can be obtained by using the manufacturing method described in Japanese Patent Application No. 2007-22206. On the other hand, the soldering portion 6 shown in FIGS. 5B and 6B is similar to the soldering portion 6 shown in FIG. The surface roughness is smaller, specifically, the surface roughness of a normal copper alloy strip (generally the arithmetic average roughness Ra in all directions is less than 0.15 μm), What is necessary is that each layer including the Sn layer is formed with a substantially uniform thickness.

  The manufacturing methods described in Patent Documents 1 and 2 use a copper alloy strip whose surface roughness is larger than that of a normal copper alloy strip as a base material, and a Ni plating layer, a Cu plating layer, and a Sn plating on the base material surface. Layers in this order, Cu plating layer and Sn plating layer in this order, or only Sn plating layer is formed, Sn plating layer is reflowed, Cu plating layer (if Ni plating is not performed, further copper alloy Cu may be supplied from the base material) and the Sn-plated layer, or the Cu-Sn alloy layer is formed from the copper alloy base material and the Sn-plated layer, and between the smoothed Sn-plated layer, Cu-Sn A part of the alloy layer is exposed on the surface (a part of the Cu—Sn alloy layer is exposed at the convex and concave portions formed on the surface of the base material).

A more specific form of the manufacturing method will be described. In the method described in Patent Document 1, the surface roughness of the base material is an arithmetic average roughness Ra of at least one direction of 0.15 μm or more, and arithmetic in all directions. The average roughness Ra is 4.0 μm or less. The average thickness of each plating layer is as follows: Ni plating layer is 3.0 μm or less, Cu plating layer is 1.5 μm or less (0.1 to 1.5 μm when Ni plating is performed), and Sn plating layer is 0 It is desirable that the average interval Sm between the irregularities calculated in the one direction is 0.01 to 0.5 mm. In addition, you may perform base plating of Ni plating, In that case, 0.01-1 micrometer is desirable for the average thickness of a base Cu plating layer.
The surface coating layer after the reflow treatment has a Cu-Sn alloy layer with a surface exposed area ratio of 3 to 75%, an average thickness of 0.1 to 3.0 [mu] m, a Cu content of 20 to 70 at%, a Sn layer The average thickness is 0.2 to 5.0 μm. Further, the arithmetic average roughness Ra in at least one direction on the base material surface is preferably 0.15 μm or more, and the arithmetic average roughness Ra in all directions is preferably 4.0 μm or less. Further, the material surface exposure interval of the Cu—Sn alloy layer In at least one direction, 0.01 to 0.5 mm is desirable, the average thickness of the Ni layer is 3 μm or less, and the average thickness of the Cu layer is 3.0 μm or less. The average thickness of the Cu layer is preferably 1.0 μm or less. Further, when the base Cu plating is performed, a base Cu layer having an average thickness of 0.01 to 1 μm exists under the Ni layer.

On the other hand, when showing the specific form described in Patent Document 2 regarding the production method, the surface roughness of the base material is an arithmetic average roughness Ra of 0.3 μm or more in at least one direction, and an arithmetic average roughness in all directions. Ra is 4.0 μm or less. Moreover, it is desirable that the average interval Sm between the irregularities calculated in the one direction is 0.01 to 0.5 mm, and the average thickness of each plating layer is a Ni plating layer of 3.0 μm or less, Cu plating The layer is preferably 1.5 μm or less (0.1 to 1.5 μm when Ni plating is performed), and the Sn plating layer is preferably 0.4 to 8.0 μm. In addition, you may perform base plating of Ni plating, In that case, 0.01-1 micrometer is desirable for the average thickness of a base Cu plating layer.
The surface coating layer after the reflow treatment has a Cu-Sn alloy layer surface exposure area ratio of 3 to 75%, an average thickness of 0.2 to 3.0 [mu] m, a Cu content of 20 to 70 at%, The average thickness is 0.2 to 5.0 μm, the arithmetic average roughness Ra in at least one direction of the material surface is 0.15 μm or more, and the arithmetic average roughness Ra in all directions is 3.0 μm or less. The arithmetic average roughness Ra in at least one direction on the base material surface is preferably 0.3 μm or more, and the arithmetic average roughness Ra in all directions is preferably 4.0 μm or less. Further, the surface exposure interval of the Cu—Sn alloy layer In at least one direction, 0.01 to 0.5 mm is desirable, the average thickness of the Ni layer is 3.0 μm or less, and the average thickness of the Cu layer is 3.0 μm or less. The average thickness of the Cu layer is preferably 1.0 μm or less. Further, when the base Cu plating is performed, a base Cu layer having an average thickness of 0.01 to 1 μm exists under the Ni layer.

  The surface roughness is measured based on JIS B0601-1994 as described in Patent Documents 1 and 2. This is the same in Japanese Patent Application No. 2007-22206. Regarding the thickness of each plating layer and the thickness of each layer constituting the surface coating layer after the reflow treatment, the measurement methods are described in Patent Documents 1 and 2.

The manufacturing method described in Japanese Patent Application No. 2007-22206 is common to Patent Documents 1 and 2 in terms of technical idea, but includes both cases where the Cu—Sn alloy layer is exposed and not exposed.
When showing a specific form of the manufacturing method described in Japanese Patent Application No. 2007-22206, the surface roughness of the base material is an arithmetic average roughness Ra of 0.4 μm or more in at least one direction, and an arithmetic average roughness in all directions. The thickness Ra is preferably 4.0 μm or less, more preferably the average interval Sm between the irregularities calculated in the one direction is 0.01 to 0.5 mm, and still more preferably the maximum height Ry in the one direction is 2. The average thickness of each plating layer is 3.0 μm or less for the Ni plating layer, 0.1 to 1.5 μm for the Cu plating layer, and 0.4 to 8.0 μm for the Sn plating layer. Is preferred. If necessary, an Sn plating layer can be further formed after the reflow treatment.

  The surface coating layer thus obtained has a Ni layer with an average thickness of 3.0 μm or less, a Cu—Sn alloy layer with an average thickness of 0.2 to 3.0 μm, and a Sn layer in a vertical section of the material ( In the case of performing Sn plating after the reflow treatment, the diameter [D1] of the smallest inscribed circle of the Sn plating layer is 0.2 μm or less, the diameter [D2] of the largest inscribed circle is 1.2 to 20 μm, The height difference [Y] between the outermost point and the outermost point of the Cu—Sn alloy layer is defined as 0.2 μm or less. Further, when [D1] is 0 μm (that is, when the Cu—Sn alloy layer is exposed), the diameter [D3] of the maximum inscribed circle of the Cu—Sn alloy layer on the material surface is 150 μm or less or / and on the material surface The maximum inscribed circle diameter [D4] of the Sn layer is desirably 300 μm or less, and the average thickness of the Cu layer is desirably 1.0 μm or less.

FIG. 7 is a diagram for explaining the above [D1], [D2] and [Y], and FIG. 7A shows a cross section 21a of the material 21 shown in FIG. When the surface 21b is rough, the vicinity of the surface of the neutral surface 22 (a vertical cross section with respect to the surface passing through the center of the plate thickness) of the base material is enlarged and schematically shown. In this example, a Ni layer 24, a Cu layer 25, a Cu—Sn alloy layer 26 and a Sn layer 27 are formed on the surface of the base material 23.
[D1] is the diameter of the smallest inscribed circle that can be drawn between the surface of the material 21 and the Cu—Sn alloy layer 26 in FIG. 7A, and [D2] is the diameter of the largest inscribed circle, [Y] is the height of the portion 21A farthest from the neutral surface 22 of the surface of the material 21 (the outermost surface point of the material 21) 21A (height from the neutral surface 22) and the Cu-Sn alloy layer 26. This is a difference in the height (height from the neutral surface 22) of a portion 26A (the outermost point of the Cu-Sn alloy layer 26) farthest from the surface neutral surface 22.
Moreover, FIG. 8 is a figure explaining said [D3] and [D4], and shows the surface of the material 21 typically. The surface is composed of the Cu—Sn alloy layer 26 and the Sn layer 27, [D3] is the diameter of the largest inscribed circle surrounded by the Sn layer 27, and [D4] is surrounded by the Cu—Sn alloy layer 26. The diameter of the largest inscribed circle.

According to Japanese Patent Application No. 2007-22206, the reasons for limiting each of the above parameters are as follows.
(1) The Ni layer suppresses the diffusion of the matrix constituent elements to the material surface, and further suppresses the growth of the Cu—Sn alloy layer to prevent the Sn layer from being consumed. While suppressing the increase in contact resistance even in a sulfurous acid gas corrosive atmosphere, it helps to obtain good solder wettability. However, when the average thickness of the Ni layer is less than 0.1 μm, the above effect cannot be sufficiently exhibited due to an increase in pit defects in the Ni layer. However, when the above effect is not particularly required, the average thickness of the Ni layer may or may not be less than 0.1 μm. On the other hand, when the Ni layer is thickened to some extent, the above effects are saturated, and when it is too thick, productivity and economic efficiency are deteriorated. Therefore, the average thickness of the Ni layer is 3.0 μm or less (including 0 μm), preferably 0.1 to 3.0 μm. More desirably, the thickness is 0.2 to 2.0 μm.
When forming the Ni layer, a base Cu layer (Cu base plating layer) may be formed between the base material and the Ni layer. Cu base plating covers defects (pits, etc.) and precipitates on the surface of the base material to improve Ni plating adhesion and enhance the reliability of Ni plating. ing. The thickness of the underlying Cu layer is preferably 0.01 to 1 μm.

(2) The Cu layer may be omitted, but when the Ni layer is formed, it helps to effectively suppress the diffusion of Ni in the Ni layer to the material surface and the excessive diffusion to the Cu-Sn alloy layer. . In particular, when the Sn layer is partially thin or absent as in the present invention (Japanese Patent Application No. 2007-22206), the deposition of Ni oxide having a very high electric resistance even after use at high temperature for a long time is suppressed. Therefore, it is effective for suppressing an increase in contact resistance for a long period of time, and also has an effect of improving the sulfurous acid gas corrosion resistance. However, if the Cu layer becomes too thick, it becomes difficult to suppress the growth of the Cu—Sn alloy layer, and the effect of preventing the consumption of the Sn layer is reduced. On the other hand, if the Cu layer becomes too thick, voids are generated between the Cu layer and the Cu—Sn alloy layer due to thermal diffusion, aging, and the like, and the heat-resistant peelability is lowered, and productivity and economy are also deteriorated. Therefore, the average thickness of the Cu layer is specified to be 1.0 μm or less. More desirably, it is 0.5 μm or less.

(3) The Cu—Sn alloy layer is very hard compared to Sn or Sn alloy forming the Sn layer. Therefore, as in the present invention (Japanese Patent Application No. 2007-22206), when [D1] is 0.2 μm or less and [y] is 0.2 μm or less, the Sn layer is dug during terminal insertion / extraction. Deformation resistance and shear resistance that shears adhesion can be suppressed, and the friction coefficient can be made extremely low. Also, when sliding or fine sliding the electrical contact part under terminal insertion / extraction or vibration environment, the contact pressure is received by a hard Cu-Sn alloy layer and the contact area between the Sn layers can be reduced. As a result, the wear and oxidation of the Sn layer are also reduced. Furthermore, when the Ni layer is formed, the Cu—Sn alloy layer helps to suppress diffusion of Ni in the Ni layer to the material surface. However, when the average thickness of the Cu—Sn alloy layer is less than 0.2 μm, particularly when the Sn layer is partially thin or not as in the present invention (Japanese Patent Application No. 2007-22206), high temperature oxidation or the like Since the amount of Ni oxide on the surface of the material due to thermal diffusion increases, the contact resistance is likely to increase, and the corrosion resistance also deteriorates, making it difficult to maintain the reliability of electrical connection. On the other hand, when it exceeds 3.0 micrometers, productivity and economical efficiency will worsen. Therefore, the average thickness of the Cu—Sn alloy layer is specified to be 0.2 to 3.0 μm. More desirably, the thickness is 0.3 to 2.0 μm.

(4) When the diameter [D1] of the minimum inscribed circle of the Sn layer exceeds 0.2 μm, the deformation resistance due to the excavation of the Sn layer and the shear resistance that shears the adhesion increase when inserting and removing the terminal, and the friction coefficient is increased. It becomes difficult to lower the thickness, and the wear and oxidation of the Sn layer due to fine sliding also increase, making it difficult to suppress an increase in contact resistance. Therefore, [D1] is defined as 0.2 μm or less. More desirably, it is 0.15 μm or less.
(5) When the diameter [D2] (see FIG. 1) of the maximum inscribed circle of the Sn layer is less than 1.2 μm, the Sn layer disappears earlier due to the consumption of the Sn layer due to thermal diffusion or aging. The effect of improving heat resistance and corrosion resistance is reduced, and at the same time, the amount of the Sn layer is not large, so that it is difficult to ensure solder wettability. On the other hand, when [D2] exceeds 20 μm, the mechanical properties may be adversely affected, resulting in poor productivity and economy. Therefore, [D2] is defined as 1.2 to 20 μm. More desirably, the thickness is 1.5 to 10 μm.

(6) When the height difference [y] between the outermost point of the material and the outermost point of the Cu—Sn alloy layer exceeds 0.2 μm, the deformation resistance and adhesion due to the excavation of the Sn layer are sheared when inserting and removing the terminal. It is difficult to lower the friction coefficient by increasing the shear resistance, and the wear and oxidation of the Sn layer due to fine sliding also increase, making it difficult to suppress the increase in contact resistance. Therefore, [y] is defined as 0.2 μm or less. More desirably, it is 0.15 μm or less.
(7) When the diameter [D1] of the minimum inscribed circle of the Sn layer is 0 μm (the Cu—Sn alloy layer is partially exposed on the surface of the material), the maximum inscribed circle of the Cu—Sn alloy layer on the surface of the material The diameter [D3] (see FIG. 2) is desirably 150 μm or less. When [D3] exceeds 150 μm, there is a case where only the contact of the Cu—Sn alloy layer may be caused particularly in an electric contact portion of a small fitting type terminal, etc., so that the effect of suppressing deterioration in heat resistance and corrosion resistance is low. Thus, it may be difficult to ensure solder wettability. More desirably, it is 100 μm or less.
(8) When the diameter [D1] of the minimum inscribed circle of the Sn layer is 0 μm, the maximum inscribed circle diameter [D4] of the Sn layer is desirably 300 μm or less. When [D4] exceeds 300 μm, the contact area between the Sn layers increases, the deformation resistance due to the digging of the Sn layer and the shear resistance that shears the adhesion increase, and the effect of reducing the friction coefficient may be reduced. . In addition, wear and oxidation of the Sn layer due to fine sliding increase, and the contact resistance may increase. More desirably, it is 200 μm or less.

(9) The surface roughness of the base material is desirably a surface roughness having an arithmetic average roughness Ra of 0.4 μm or more in at least one direction and an arithmetic average roughness Ra of 4.0 μm or less in all directions. . If Ra is less than 0.4 μm in any direction, even if the plating thickness and reflow conditions are adjusted, it is difficult to satisfy the specification (particularly [D2]) of this application (Japanese Patent Application No. 2007-22206). If it exceeds 4.0 μm, the melt fluidity of Sn is deteriorated.
Desirably, the average interval Sm of the unevenness in the one direction is 0.01 to 0.5 mm, and if it is less than 0.01 mm, the specification (particularly [D2]) of the present application (Japanese Patent Application No. 2007-22206) is satisfied. When the thickness exceeds 0.5 mm, there is a high possibility that [D3] and [D4] will be outside the specified range. More preferably, the maximum height Ry in the one direction is 2.0 to 20 μm. Outside this range, it may be difficult to satisfy the specification (particularly [D2]) of the present application (Japanese Patent Application No. 2007-22206).

In addition, as described in the prior patent documents 1 and 2 and Japanese Patent Application No. 2007-22206, the Sn layer, the Cu layer, and the Ni layer are Sn, Cu, Ni metal, Sn alloy, Cu alloy, and Ni alloy, respectively. including.
When the Sn layer is made of an Sn alloy, examples of constituents other than Sn of the Sn alloy include Pb, Bi, Zn, Ag, and Cu. Pb is preferably less than 50% by mass, and other elements are preferably less than 10% by mass.
The Cu layer may contain a small amount of component elements contained in the base material. Further, when the Cu layer is made of a Cu alloy, examples of components other than Cn of the Cn alloy include Sn and Zn. In the case of Sn, less than 50% by mass, and for other elements, less than 5% by mass is desirable.
A small amount of component elements contained in the base material may be mixed in the Ni layer. Further, when the Ni layer is made of a Ni alloy, Cu, P, Co and the like can be cited as constituent components other than Ni of the Ni alloy. For Cu, 40% by mass or less, and for P and Co, 10% by mass or less are desirable.
Similarly, the Cu plating layer, the Sn plating layer, and the Ni plating layer include Cu alloy, Sn alloy, and Ni alloy in addition to Cu, Sn, and Ni metal, respectively. When the Ni plating layer, the Cu plating layer, and the Sn plating layer are made of a Ni alloy, a Cu alloy, and a Sn alloy, respectively, the respective alloys described with respect to the Ni layer, the Cu layer, and the Sn layer can be used.

(Reference example)
Here, the conductive material for connecting parts described in Japanese Patent Application No. 2007-22206 (not disclosed at the present time) and the manufacturing method thereof have the effects (mainly low friction coefficient and electrical reliability) described so far. An example described in Japanese Patent Application No. 2007-22206 will be described. In addition, since it is known by the literature that the conductive material for connecting parts and the manufacturing method thereof described in Patent Documents 1 and 2 have the above-described effects, the description thereof is omitted here.

[Production of test materials]
The prepared test material No. Tables 1 and 2 show the outline of the manufacturing steps 1 to 31.
As a base material, a Cu alloy plate containing 1.8% by mass of Ni, 0.40% by mass of Si, 0.10% by mass of Sn and 1.1% by mass of Zn in Cu is used. A base material having a surface roughness of Vickers hardness of 200 and a thickness of 0.25 mm, with or without surface roughening using a work roll roughened by shot blasting or the like. Finished. The surface roughness of the base material is the test material No. in the examples. 1-18 and the test material No. of a comparative example. In Nos. 19 to 22, 24, and 25, Ra, Sm, and Ry are within the above-described desirable ranges. 23, Ra and Sm are within the desired range, but Ry is less than the lower limit value. 26-31 is less than the lower limit of the range where Ra and Ry are desirable.
Subsequently, the surface of the base material is subjected to Ni plating (or not), Cu plating (or not), Sn plating, reflow treatment, and ammonium hydrogen fluoride aqueous solution immersion treatment. Performed (or not performed), and Sn plating was performed again (or not performed).

  Average thickness of Ni layer, Cu layer and Cu-Sn alloy layer of the prepared test material, coating layer form ([D1], [D2], [y]) in the vertical cross section of the material, and coating layer on the material surface The form ([D3], [D4]) was measured as follows. The results are shown in Tables 3 and 4.

[Average thickness measurement method of Ni layer, Cu layer and Cu-Sn alloy layer]
The cross section of the test material processed by the microtome method is subjected to argon ion etching if necessary, and observed using an SEM (scanning electron microscope) equipped with an EDX (energy dispersive X-ray spectrometer). The average thicknesses of the Ni layer, the Cu layer, and the Cu—Sn alloy layer were calculated from the density of the resulting composition image (excluding contrast such as dirt and scratches) by image analysis processing. The measurement cross section was a vertical cross section perpendicular to the rolling direction performed during the surface roughening treatment.

[Method for measuring the shape of the vertical cross section of the material surface]
The cross section of the test material processed by the microtome method is subjected to argon ion etching if necessary, and observed using an SEM (scanning electron microscope) equipped with an EDX (energy dispersive X-ray spectrometer). [D1], [D2], and [y] were calculated from the density of the obtained composition image (excluding contrast such as dirt and scratches) by image analysis processing. The measurement cross section is a vertical cross section in a direction perpendicular to the rolling direction performed during the surface roughening treatment.
[Method for measuring surface morphology of material]
The surface of the test material is observed using an SEM (scanning electron microscope) equipped with an EDX (energy dispersive X-ray spectrometer), and the resulting composition image is shaded (excluding contrast such as dirt and scratches). Then, the maximum inscribed circle diameter [D3] of the Cu—Sn alloy layer and the maximum inscribed circle diameter [D4] of the Sn layer were respectively calculated by image analysis processing.

  In addition, for the obtained test materials, friction coefficient evaluation test, contact resistance evaluation test during fine sliding wear test, contact resistance evaluation test after high temperature standing test, heat-resistant peeling test, contact resistance evaluation test after sulfite gas corrosion test The lead-free solder wetting test and the lead-free solder wetting test were performed as follows. The results are shown in Tables 5 and 6.

[Friction coefficient evaluation test]
The shape of the indented portion of the electrical contact in the fitting type connecting part was simulated and evaluated using an apparatus as shown in FIG. First, each test material No. 1 to 31 is fixed to a horizontal base 32, and a test material No. The coating layers were brought into contact with each other by placing a female test piece 33 of a hemispherical workpiece cut out from 31 (with an inner diameter of φ1.5 mm). Subsequently, the male test piece 31 is pressed by applying a load (weight 34) of 3.0 N to the female test piece 33 and using a horizontal load measuring device (Aiko Engineering Co., Ltd .; Model-2152). The sample was pulled in the horizontal direction (sliding speed was 80 mm / min), and the maximum frictional force F (unit: N) up to a sliding distance of 5 mm was measured. The coefficient of friction was determined by the following formula (1). In addition, 35 is a load cell and the arrow is a sliding direction.
Friction coefficient = F / 3.0 (1)

[Contact resistance evaluation test during fine sliding wear test]
The shape of the indented portion of the electrical contact in the fitting type connection part was simulated and evaluated using a sliding tester (Yamazaki Seiki Laboratory Co., Ltd .; CRS-B1050CHO) as shown in FIG. First, test material No. A male test piece 36 of a plate material cut out from 31 is fixed to a horizontal base 37, and each test material No. The coating layers were brought into contact with each other by placing a female test piece 38 of a hemispherical material cut out from 1 to 31 (with an inner diameter of φ1.5 mm). Subsequently, a load of 2.0 N (weight 39) is applied to the female test piece 38 to hold the male test piece 36, a constant current is applied between the male test piece 36 and the female test piece 38, and the stepping motor 40 is used. Then, the male test piece 36 is slid in the horizontal direction (sliding distance is 50 μm, sliding frequency is 1.0 Hz), and the maximum contact resistance up to 1000 times of sliding is determined by the four-terminal method using an open voltage of 20 mV, The measurement was performed under the condition of a current of 10 mA. The arrow indicates the sliding direction.

[Contact resistance evaluation test after high-temperature storage test]
Each test material No. The plate specimens cut out from 1 to 31 were subjected to heat treatment at 175 ° C. × 1000 hr in the air, and then contact resistance was measured by the four-terminal method (the Au probe was slid in the horizontal direction, the load Was measured under the conditions of 3.0 N, a sliding distance of 0.30 mm, a sliding speed of 1.0 mm / min, an open-circuit voltage of 20 mV, and a current of 10 mA).
[Heat-resistant peel test]
Each test material No. The test pieces of the plate material cut out from 1 to 31 were bent by 90 ° (bending radius was set to 0.7 mm), subjected to heat treatment at 175 ° C. × 1000 hr in the atmosphere, then bent back, The appearance of the coating layer was evaluated for the presence or absence of peeling.

[Contact resistance evaluation test after sulfurous acid gas corrosion test]
First, each test material No. After performing a sulfurous acid gas corrosion test on a test piece of a plate material cut out from 1 to 31, a sulfurous acid gas concentration of 25 ppm, a temperature of 35 ° C., a humidity of 75% RH, and a time of 96 hours, the contact resistance was measured by a four-terminal method ( The Au probe was slid in the horizontal direction, and the load was 3.0 N, the sliding distance was 0.30 mm, the sliding speed was 1.0 mm / min, the open-circuit voltage was 20 mV, and the current was 10 mA.

[Lead-free solder wetting test]
Each test material No. After the inactive flux was dip-applied for 1 second to the test piece of the plate material cut out from 1 to 31, the zero cross time and the maximum wet stress were measured by the meniscograph method (255 ° C. Sn-3.0Ag-0. It was immersed in 5Cu solder, and the immersion speed was measured at 25 mm / sec, the immersion depth was 12 mm, and the immersion time was 5.0 sec). Further, the appearance of the test pieces after the solder immersion was evaluated for the presence or absence of solder wettability.

As shown in Table 3 and Table 5, the test material No. Nos. 1 to 14 satisfy the provisions of Japanese Patent Application No. 2007-22206 regarding the coating layer configuration (each coating layer thickness and [D1], [D2], [y]), have a low coefficient of friction, The contact resistance, the contact resistance after the high temperature standing test, the appearance after the heat-resistant peeling test, the contact resistance after the sulfurous acid gas corrosion test, and the lead-free solder wettability showed excellent characteristics. However, when [D1] = 0, [D3] or / and [D4] exceed the provisions of Japanese Patent Application No. 2007-22206. Nos. 12 to 14 each have a relatively low level of one or more characteristics compared to other test materials.
Test material No. Nos. 15 to 18 are examples in which the average thickness of the Ni layer is less than 0.1 μm, and the coating layer configuration (each coating layer thickness and [D1], [D2], [y]) is as described in Japanese Patent Application No. 2007-22206. It meets the requirements, all have a low coefficient of friction, and the contact resistance during the microsliding wear test is relatively low.

Test material No. 19 to 25, the average thickness of any one of the Cu layer and the Cu—Sn alloy layer does not satisfy the provisions of Japanese Patent Application No. 2007-22206, or the average thickness of the Ni layer is outside the desired range, or Any of “D1”, [D2], and [y] does not satisfy the provisions of Japanese Patent Application No. 2007-22206, and any one or a plurality of characteristics are inferior accordingly.
The test material No. No. 21 is a test material prepared without applying Cu plating after Ni plating, and since a Ni—Sn alloy layer was formed instead of a Cu—Sn alloy layer, contact resistance after a high temperature standing test, and after a sulfurous acid gas corrosion test High contact resistance.

Test material No. Nos. 26 to 31 are test materials prepared without subjecting the surface of the base material to roughening, and do not satisfy any one or two or more of the provisions of Japanese Patent Application No. 2007-22206. Therefore, any one or two or more Inferior properties.
The test material No. No. 26 is a test material in which Ni plating is not applied and the Sn coating layer is completely disappeared by a long reflow process. No. 27 is a test material in which most of the Sn coating layer disappeared after a long reflow treatment. No. 28 is not subjected to Ni plating or Cu plating, and the test material No. 31 is not plated with Ni.

It is a figure explaining the manufacturing method of the terminal for fitting type connectors concerning the present invention. It is a figure explaining the manufacturing method of the terminal for fitting type connectors concerning the present invention. It is a figure explaining the manufacturing method of the terminal for fitting type connectors concerning the present invention. It is typical sectional drawing of the terminal fitting part (a) and soldering part (b) of the terminal for fitting type connectors which concerns on this invention. It is typical sectional drawing of the terminal fitting part (a) and soldering part (b) of the terminal for fitting type connectors which concerns on this invention. It is typical sectional drawing of the terminal fitting part (a) and soldering part (b) of the terminal for fitting type connectors which concerns on this invention. It is a figure which shows typically the coating layer structure which appears in the perpendicular cross section with respect to the surface of the material manufactured by the manufacturing method of Japanese Patent Application No. 2007-22206. It is a figure which shows typically the coating layer structure which appears on the surface of the material manufactured by the manufacturing method of Japanese Patent Application No. 2007-22206. It is a conceptual diagram of the friction coefficient measurement jig | tool used by the Example of Japanese Patent Application No. 2007-22206. It is a conceptual diagram of the fine sliding wear measuring jig used in the example of Japanese Patent Application No. 2007-22206.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Copper alloy strip 2 Terminal material 5 Terminal fitting part 6 Soldering part 7 Base material 8 Base plate surface 9 Base material punching end surface 11 Ni layer 12 Cu-Sn alloy layer 13 Sn layer 14 Sn plating layer

Claims (22)

This is a fitting connector terminal manufactured by post-plating and reflow treatment on a punched copper alloy sheet, and has a terminal fitting part and a soldering part, and the surface of the base plate at the terminal fitting part A fitting type connector characterized in that the roughness is larger than that of the soldered portion, 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 a reflow process. Terminal. The terminal for fitting type connectors according to claim 1, further comprising a Cu layer under the Cu—Sn alloy layer as a surface coating layer. This is a fitting connector terminal manufactured by post-plating and reflow treatment on a punched copper alloy sheet, and it has a terminal fitting part and a soldering part, and the surface of the base plate at the terminal fitting part The fitting is characterized in that the roughness is formed larger than the soldering part, the Ni layer, 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 Type connector terminal. 4. The fitting connector terminal according to claim 3, wherein a Cu layer is provided between the Ni layer and the Cu-Sn alloy layer as a surface coating layer. In the terminal fitting portion, the surface roughness of the base plate is at least an arithmetic average roughness Ra in one direction of 0.15 μm or more and an arithmetic average roughness Ra in all directions of 4.0 μm or less. The terminal for fitting type connectors as described in any one of Claims 1-4 characterized by these. 6. The fitting type connector according to claim 5, wherein a part of the Cu-Sn alloy layer is exposed on the surface of the material in the terminal fitting portion, and the Sn layer covers the entire surface in the soldering portion. Terminal. The Cu—Sn alloy layer has an average thickness of 0.1 to 3.0 μm, a Cu content of 20 to 70 at%, and the Sn layer has an average thickness of 0.2 to 5.0 μm. In the terminal fitting portion, the surface roughness of the base plate is at least an arithmetic average roughness Ra in one direction of 0.15 μm or more, an arithmetic average roughness Ra in all directions is 4.0 μm or less, and 5. The Cu—Sn alloy layer is partially exposed on the material surface, the exposed area ratio is 3 to 75%, and the Sn layer covers the entire surface in the soldered portion. The terminal for fitting type connectors described in any one of. The Cu—Sn alloy layer has an average thickness of 0.2 to 3.0 μm, a Cu content of 20 to 70 at%, and the Sn layer has an average thickness of 0.2 to 5.0 μm. The surface roughness of the terminal fitting portion plate surface is such that the arithmetic average roughness Ra in at least one direction is 0.15 μm or more, the arithmetic average roughness Ra in all directions is 3.0 μm or less, and the Cu—Sn 5. The alloy layer according to claim 1, wherein a part of the alloy layer is exposed on the material surface, the exposed area ratio is 3 to 75%, and the Sn layer covers the entire surface in the soldered portion. The described connector for mating connector. In the terminal fitting portion, the surface roughness of the base plate is at least an arithmetic average roughness Ra in one direction of 0.3 μm or more and an arithmetic average roughness Ra in all directions of 4.0 μm or less. The terminal for fitting type connectors according to claim 8 characterized by these. The average thickness of the Cu—Sn alloy layer is 0.2 to 3.0 μm, and the diameter of the smallest inscribed circle of the Sn layer [D1] in a cross section perpendicular to the material surface of the terminal fitting portion plate surface Is 0.2 μm or less, the diameter [D2] of the maximum inscribed circle of the Sn layer is 1.2 to 20 μm, and the altitude difference [y] between the outermost point of the material and the outermost point of the Cu—Sn alloy layer is 3. The fitting connector terminal according to claim 1 or 2, wherein the Sn layer is 0.2 [mu] m or less, and the Sn layer covers the entire surface in the soldered portion. The average thickness of the Ni layer is 3.0 μm or less, the average thickness of the Cu—Sn alloy layer is 0.2 to 3.0 μm, and in a cross section perpendicular to the material surface of the terminal fitting portion plate surface, The diameter [D1] of the minimum inscribed circle of the Sn layer is 0.2 μm or less, the diameter [D2] of the maximum inscribed circle of the Sn layer is 1.2 to 20 μm, the outermost point of the material, and the Cu—Sn alloy 5. The fitting type according to claim 3, wherein the height difference [y] from the outermost point of the layer is 0.2 μm or less, and the Sn layer covers the entire surface in the soldered portion. Connector terminal. In the terminal fitting portion, the surface roughness of the base plate is at least an arithmetic average roughness Ra in one direction of 0.4 μm or more and an arithmetic average roughness Ra in all directions of 4.0 μm or less. The terminal for fitting type connectors according to claim 10 or 11 characterized by things. The terminal for fitting type connectors according to any one of claims 10 to 12, further comprising an Sn plating layer formed after the reflow treatment as the surface coating layer. A method for manufacturing a terminal for a fitting connector having a terminal fitting portion and a soldering portion, in which a copper alloy sheet is subjected to punching processing, and the terminal material is connected in a chain in the length direction via a strip-shaped connecting portion. The copper alloy sheet was formed, and simultaneously with the punching process or before or after the punching process, the copper alloy sheet was pressed to increase the surface roughness of the terminal material plate surface at the terminal fitting portion. Thereafter, the copper alloy sheet is post-plated to form a Cu plating layer and an Sn plating layer in this order, and then the Sn plating layer is reflowed to form a Cu-Sn alloy layer from the Cu plating layer and the Sn plating layer. And a method for producing a fitting connector terminal, wherein the Sn plating layer is smoothed. A method for manufacturing a terminal for a fitting connector having a terminal fitting portion and a soldering portion, in which a copper alloy sheet is subjected to punching processing, and the terminal material is connected in a chain in the length direction via a strip-shaped connecting portion. The copper alloy sheet was formed, and simultaneously with the punching process or before or after the punching process, the copper alloy sheet was pressed to increase the surface roughness of the terminal material plate surface at the terminal fitting portion. Thereafter, the copper alloy sheet is post-plated to form a Ni plating layer, a Cu plating layer, and a Sn plating layer in this order, and then the Sn plating layer is reflowed to form Cu from the Cu plating layer and the Sn plating layer. A method for producing a fitting connector terminal, characterized by forming a Sn alloy layer and smoothing a Sn plating layer. A method for manufacturing a terminal for a fitting connector having a terminal fitting portion and a soldering portion, in which a copper alloy sheet is subjected to punching processing, and the terminal material is connected in a chain in the length direction via a strip-shaped connecting portion. The copper alloy sheet was formed, and simultaneously with the punching process or before or after the punching process, the copper alloy sheet was pressed to increase the surface roughness of the terminal material plate surface at the terminal fitting portion. Thereafter, the copper alloy sheet is post-plated to form an Sn plating layer, and then the Sn plating layer is reflowed to form a Cu—Sn alloy layer from the copper alloy base material and the Sn plating layer and Sn plating. A method of manufacturing a fitting connector terminal, comprising smoothing a layer. As a result of the pressing, the surface roughness of the terminal material plate surface in the terminal fitting portion is such that the arithmetic average roughness Ra in at least one direction is 0.15 μm or more and the arithmetic average roughness Ra in all directions is 4.0 μm. The method for manufacturing a fitting connector terminal according to any one of claims 14 to 16, wherein the manufacturing method is increased to the following. As a result of the pressing, the surface roughness of the terminal material plate surface in the terminal fitting portion is such that the arithmetic average roughness Ra in at least one direction is 0.15 μm or more and the arithmetic average roughness Ra in all directions is 4.0 μm. The surface area of the terminal-fitting portion plate surface is exposed to a part of the Cu-Sn alloy layer by the reflow treatment, and the exposed area ratio is set to 3 to 75%. The method for manufacturing a terminal for a fitting connector according to any one of claims 14 to 16, wherein the -Sn alloy layer is not exposed. As a result of the pressing, the surface roughness of the terminal material plate surface at the terminal fitting portion is such that the arithmetic average roughness Ra in at least one direction is 0.3 μm or more and the arithmetic average roughness Ra in all directions is 4.0 μm. The surface area of the terminal fitting portion plate surface is exposed to a part of the Cu-Sn alloy layer by the reflow treatment, and the exposed area ratio is set to 3 to 75%. The method for producing a terminal for a fitting connector according to any one of claims 14 to 16, wherein the Sn alloy layer is not exposed. By the press working, the surface roughness of the terminal material plate surface in the terminal fitting portion is such that the arithmetic average roughness Ra in at least one direction is 0.4 μm or more, and the arithmetic average roughness Ra in all directions is 4.0 μm. The diameter [D1] of the minimum inscribed circle of the Sn layer after the reflow treatment is 0.2 μm or less in the vertical cross section with respect to the material surface of the terminal fitting portion plate surface, and the maximum inscribed circle of the Sn layer is The diameter [D2] is 1.2 to 20 [mu] m, the height difference [y] between the outermost point of the material and the outermost point of the Cu-Sn alloy layer is 0.2 [mu] m or less, and the Cu-Sn in the soldered portion The method for manufacturing a fitting connector terminal according to any one of claims 14 to 16, wherein the alloy layer is not exposed. By the press working, the surface roughness of the terminal material plate surface in the terminal fitting portion is such that the arithmetic average roughness Ra in at least one direction is 0.4 μm or more, and the arithmetic average roughness Ra in all directions is 4.0 μm. In addition, Sn plating is further performed after the reflow treatment, and the diameter [D1] of the minimum inscribed circle of the Sn layer after Sn plating is 0.2 μm or less in the cross section perpendicular to the material surface of the terminal fitting portion plate surface. The diameter [D2] of the maximum inscribed circle of the layer is 1.2 to 20 μm, and the height difference [y] between the outermost point of the material and the outermost point of the Cu—Sn alloy layer is 0.2 μm or less. The manufacturing method of the terminal for fitting type connectors as described in any one of Claims 14-16 characterized by the above-mentioned. The fitting type according to any one of claims 14 to 21, wherein instead of performing the pressing process, a rolling process is performed to increase a surface roughness of a terminal material plate surface in the terminal fitting part. A method for manufacturing a connector terminal.

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