JP4341762B2 - Connector material for electronic and electrical equipment composed of high-strength Cu alloy with excellent rolling and bending workability - Google Patents

Description

【００１４】
【表２】

【００１５】
【発明の効果】
表１、２に示される結果から、従来高強度Ｃｕ合金に合金成分としてＡｌを含有させてなる高強度Ｃｕ合金で構成された本発明コネクター材１〜１５は、Ａｌを含有しない従来高強度Ｃｕ合金からなる従来コネクター材１〜１３と同等の高強度を保持した上で、これより一段とすぐれた圧延性と曲げ加工性を有することが明らかである。
上述のように、この発明のコネクター材は、すぐれた圧延性と曲げ加工性を有する高強度Ｃｕ合金で構成されているので、各種電子電気機器への適用に際して、薄肉化および複雑曲げ加工を可能とするものであり、したがってこれら電子電気機器の小型化および軽量化、さらに多機能化に十分満足に対応できるものである。[0001]
BACKGROUND OF THE INVENTION
The present invention is a connector for electronic and electrical equipment which is composed of a high-strength Cu alloy excellent in rolling property and bending workability, and thus enables not only thinning of the economy but also complicated bending work with strong bending work. It relates to materials.
[0002]
[Prior art]
Conventionally, many Cu alloys have been applied as connector materials for various electronic and electrical devices, and among these Cu alloys, in wt% (hereinafter,% indicates wt%),
Cr: 0.07 to 0.4%,
Zr: 0.01 to 0.15%,
Ti: 0.01 to 0.4%,
Co and / or Fe: 0.01 to 1%,
Cu alloy with a composition consisting of Cu and the inevitable impurities in the balance is attracting attention as a connector material for various electronic and electrical equipment because of its high strength and high conductivity required for connectors and excellent spring properties. ing.
[0003]
[Problems to be solved by the invention]
On the other hand, with the recent reduction in size and weight of various electronic and electrical devices and the increase in functionality, there is a tendency for connectors, which are structural parts thereof, to be further reduced in thickness and complex bending workability. In the connector material made of the conventional high-strength Cu alloy having the above composition, the ear cracks are easily generated during the cold rolling in the production process, and therefore, it is difficult to further reduce the thickness of the connector material when applied as a connector material. In addition, since it does not have sufficiently satisfactory characteristics in terms of bending workability, the occurrence of cracks cannot be avoided in complex bending workability involving strong bending work.
[0004]
[Means for Solving the Problems]
In view of the above, the inventors of the present invention focused on the conventional high-strength Cu alloy having the above composition in order to develop a Cu alloy suitable for use in the manufacture of connectors for various electronic devices in recent years. As a result, when Al is contained in the conventional high-strength Cu alloy having the above composition in an amount of 0.002 to 0.4% as an alloy component, the resulting Cu alloy has the same strength as the conventional high-strength Cu alloy. In addition, it has excellent electrical conductivity and springiness, and the occurrence of ear cracks during cold rolling is remarkably suppressed, and it has excellent bending workability. The result of the research was that it was possible to reduce the thickness and make complex bending.
[0005]
This invention was made based on the above research results, and Cr: 0.07 to 0.4%, Zr: 0.01 to 0.15%, Ti: 0.01 to 0.4% , Co, or Co and Fe (hereinafter referred to as Co / Fe): 0.01 to 1%, Al: 0.002 to 0.4%, with the remainder consisting of Cu and inevitable impurities It consists of a high-strength Cu alloy with excellent rolling properties and bending workability, and is characterized by a connector material for electronic and electrical equipment that has made it possible to perform complicated bending work with economical thinning and strong bending work. is there.
[0006]
Next, the reason for limiting the component composition of the high-strength Cu alloy constituting the connector material of the present invention as described above will be described.
(A) Cr
The Cr component dissolves in the base material to improve the spring property, and has the effect of finely depositing on the base material to improve the strength. However, if its content is less than 0.07%, the desired spring property and strength are achieved. On the other hand, if the content exceeds 0.4%, coarse Cr particles are precipitated, which causes a decrease in plating properties. .4%, preferably 0.08 to 0.28%.
[0007]
(B) Zr
The Zr component combines with Cu to form an intermetallic compound, and finely precipitates on the substrate together with the fine Cr, and has the effect of further improving the strength in the coexistence with the fine Cr. If it is less than 01%, in addition to the above-mentioned strength improvement by fine Cr, further improvement in strength cannot be achieved. On the other hand, if its content exceeds 0.15%, it is easy to cause ear cracks in cold-rolled material during cold rolling. Therefore, the content was determined to be 0.01 to 0.15%, desirably 0.02 to 0.1%.
[0008]
(C) Ti and Co / Fe
These components are bonded to each other to form a Ti—Co / Fe intermetallic compound, and finely precipitated on the substrate together with the fine Cr and fine Cu—Zr intermetallic compounds, and the fine Cr and fine Cu—Zr metal. In the coexistence with the intermetallic compound, it has the effect of further improving the strength. However, when the content of either Ti or Co / Fe is less than 0.01% for Ti and less than 0.01% for Co / Fe, In addition to the strength improvement due to the fine Cr and fine Cu-Zr intermetallic compound, the strength cannot be further improved. On the other hand, even if the content is Ti or Co / Fe, 0.4% for Ti, Co / Fe When the content of Fe exceeds 1%, the conductivity decreases rapidly. Therefore, the content thereof is Ti: 0.01 to 0.4%, preferably 0.05 to 0.2%, C /Fe:0.01～1Pasento, preferably defined as 0.1 to 0.4 percent.
[0009]
(D) Al
As described above, the Al component significantly suppresses the occurrence of ear cracks during cold rolling, thereby enabling economical rolling to a cold-rolled material with a thin plate thickness, thereby facilitating the processing of thin connector materials. In addition, it has the effect of improving bending workability and thus enabling complex bending work when applied as a connector material, but if the content is less than 0.002%, the desired improvement effect cannot be obtained in the action, On the other hand, if the content exceeds 0.4%, the conductivity will decrease, so the content is determined to be 0.002 to 0.4%, preferably 0.01 to 0.2%. .
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, the connector material of the present invention will be specifically described with reference to examples.
Using a normal electric furnace, in a reducing atmosphere with CO gas, each Cu alloy having the composition shown in Tables 1 and 2 is melted and cast into an ingot having a cross-sectional dimension of 180 mm × 450 mm by continuous casting. The ingot was cut into a length of 2000 mm, and a hot rolled sheet having a thickness of 10 mm was formed at a hot rolling start temperature of 920 ° C., and a sculpting having a thickness of 0.5 mm was formed on the surface of the hot rolled sheet. Are applied to the hot-rolled sheet having a thickness of 9 mm, cold-rolled to a thickness of 4 mm in two passes, and further to a thickness of 2 mm in two passes, as shown in Tables 1 and 2, respectively. Invention connector materials 1 to 15 and conventional connector materials 1 to 13 made of a high-strength Cu alloy having a component composition were produced.
[0011]
For the various connector materials obtained as a result, for the purpose of evaluating the strength first, a sample was cut out from this, and the tensile strength was measured in a state where precipitation heat treatment was performed in the atmosphere at a temperature of 500 ° C. for 100 minutes. did.
Subsequently, the above-mentioned various connector materials were subjected to a bending test in accordance with the communication machine industry association technical standard “W-bending test method for metal material” (CES · MOOO2-5).
The above bending test is performed by the following molds, that is, a lower mold having a top surface in which two V-grooves are arranged side by side (presenting a W shape when viewed from the front), and two parallel arrangements of the lower mold upper surface. The upper die has an upper die having a bottom surface in which two chevron shapes corresponding to the V-groove are arranged side by side, and the radius (R) of the central top portion between the two V-grooves on the upper surface of the lower die and the lower surface of the upper die A lower die and an upper die having the same radius (R) of the central valley between the two chevrons are set as one set, and the radius (R) of the central top of the lower die and the central valley of the upper die are respectively set. Performed using 12 types of dies that were changed in 12 steps from 0.2R (mm) to 2.4R (mm), and samples of various connector materials having a thickness of 2 mm after the cold rolling as described above The sample is bent into a W shape by applying the lower surface of the upper die to the upper surface of the sample, and the top of the sample bent into the W shape (front Measures the radius (R) of the mold used when cracks are observed on the upper surface of the center top of the lower mold and the central valley of the upper mold), that is, the critical radius (R) of crack generation. did. Therefore, the smaller the critical radius (R) of cracking, the better the bending workability.
[0012]
Furthermore, for the purpose of evaluating the rollability of the above various connector materials, cold rolling in which the thickness is reduced by 0.1 mm in one rolling is applied to the cold-rolled sheet having a thickness of 2 mm after the cold-rolling. It applied continuously and the thickness of the cold-rolled board at the time of the occurrence of an ear crack in the cold-rolled sheet, that is, the critical thickness at which the ear crack was generated was measured. In this case, the smaller the value of the critical thickness at which the ear cracks are generated, the better the rollability. The measurement results are shown in Tables 1 and 2.
[0013]
[Table 1]

[0014]
[Table 2]

[0015]
【The invention's effect】
From the results shown in Tables 1 and 2, the connector materials 1 to 15 of the present invention composed of a high-strength Cu alloy obtained by adding Al as an alloy component to a conventional high-strength Cu alloy are the conventional high-strength Cu that does not contain Al. It is clear that it has excellent rolling properties and bending workability while maintaining high strength equivalent to that of the conventional connector materials 1 to 13 made of an alloy.
As described above, the connector material of the present invention is composed of a high-strength Cu alloy having excellent rollability and bending workability, so that it can be thinned and complicatedly bent when applied to various electronic devices. Therefore, it is possible to satisfactorily cope with the reduction in size and weight of these electronic and electrical devices and the increase in functionality.

Claims (1)

% By weight
Cr: 0.07 to 0.4%,
Zr: 0.01 to 0.15%,
Ti: 0.01 to 0.4%,
Co, or Co and Fe : 0.01 to 1%,
An electronic / electric apparatus comprising a high-strength Cu alloy having excellent rolling properties and bending workability, which contains Al: 0.002 to 0.4%, and the balance is composed of Cu and inevitable impurities Connector material.