JP2016125092A - Copper alloy for electronic and electrical device, copper alloy thin sheet for electronic and electrical device, component for electronic and electrical device, terminal and bus bar - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a copper ally for electronic and electrical device excellent in bearing force, conductivity, Vickers hardness and suitable for components for electronic and electrical device.SOLUTION: A copper ally for electronic and electrical device contains Zr of 0.01 mass% or more and less than 0.11 mass%, Si of 0.0001 mass% or more and less than 0.03 mass% and the balance Cu with inevitable impurities of which total content of B, P, Ni, Cr, Ti, Fe, Co is less than 100 massppm and has percentage of X ray diffraction strength from [220] face on a material surface, R[220]=I[220]/(I[111]+I[200]+I[220]+I[311]+I[331]+I[420]) of 0.3 or more.SELECTED DRAWING: None

Description

  The present invention relates to a copper alloy for electronic / electric equipment suitable for electronic / electric equipment parts such as lead frames, terminals, connectors, relays, bus bars, etc., and for electronic / electric equipment comprising the copper alloy for electronic / electric equipment. The present invention relates to a copper alloy sheet, parts for electronic and electrical equipment, terminals, and bus bars.

Conventionally, copper or copper alloy having high conductivity is used for electronic / electric equipment parts such as terminals such as connectors, relays, lead frames, and bus bars.
Along with the downsizing of electronic devices and electrical devices, the components for electronic and electrical devices used in these electronic devices and electrical devices are being made smaller and thinner. For this reason, high strength and electrical conductivity are required for materials constituting electronic / electric equipment parts. In particular, as described in Non-Patent Document 1, a copper alloy having high proof strength is desirable as a copper alloy used as a component for electronic / electric equipment such as a terminal such as a connector, a relay, a lead frame, or a bus bar.
Here, as a material used for electronic / electric equipment parts such as terminals such as connectors, relays, lead frames, and bus bars, Cu-Zr alloys and the like are proposed in Patent Documents 1-3.

JP-A-52-003524 JP-A-63-130737 Japanese Unexamined Patent Publication No. 06-279895

Yukiya Nomura, “Technology Trends of High Performance Copper Alloy Sheets for Connectors and Our Development Strategy”, Kobe Steel Technical Report Vol. 54No. 1 (2004) p. 2-8

By the way, terminals for connectors and the like, components for electronic and electrical equipment such as relays, lead frames and bus bars are manufactured by, for example, punching a copper alloy plate material, and performing bending or the like as necessary. ing. For this reason, the above-mentioned copper alloy is also required to have good shear workability so that wear of the press mold and generation of burrs can be suppressed in press punching or the like.
Here, in order to ensure high electrical conductivity, the above-described Cu—Zr-based alloy has a composition close to that of pure copper with a small content of additive elements such as Zr, has high ductility, and good shear workability. It wasn't. More specifically, there has been a problem that when press punching is performed, burrs are generated and punching cannot be performed with high dimensional accuracy. In addition, there is a problem that the mold is easily worn and a problem that a lot of punching waste is generated.

In particular, with the recent miniaturization and weight reduction of electronic devices and electric devices, terminals for connectors used in these electronic devices and electric devices, etc., for electronic and electric devices such as relays, lead frames, bus bars, etc. There is a demand for further miniaturization and thinning of parts. For this reason, from the viewpoint of molding electronic / electric equipment parts with high dimensional accuracy, a copper alloy having sufficiently improved shearing workability is required as a material constituting these electronic / electric equipment parts.
Here, as a means for improving the shear workability of the copper alloy, it is effective to increase the Vickers hardness of the copper alloy. Further, when the Vickers hardness of the copper alloy is increased, the surface damage resistance (abrasion resistance) is also improved. Therefore, it is desired that the above-mentioned Vickers hardness is high as a copper alloy used as a component for electronic / electric equipment.

Further, terminals such as connectors are required to have higher yield strength than conventional ones. In particular, when producing a typical box-type female terminal by pressing a copper alloy plate, the longitudinal direction of the female terminal is taken in a direction perpendicular to the rolling direction, so the direction perpendicular to the rolling direction It is desirable to have a high yield strength.
Furthermore, in parts for electronic / electric equipment with large power consumption used in hybrid vehicles, electric vehicles, and the like, it is necessary to ensure high conductivity in order to suppress resistance heat generation during energization.

  The present invention has been made in view of the above-described circumstances, and is excellent in yield strength, electrical conductivity, and Vickers hardness, and suitable for electronic / electric equipment parts. An object of the present invention is to provide a copper alloy thin plate for electronic / electric equipment, a component for electronic / electric equipment, a terminal, and a bus bar made of a copper alloy for electric equipment.

  In order to solve this problem, the copper alloy for electronic and electrical equipment of the present invention contains Zr in a range of 0.01 mass% to less than 0.11 mass%, Si in a range of 0.0001 mass% to less than 0.03 mass%, with the balance remaining. Cu and inevitable impurities, the total content of B, P, Ni, Cr, Ti, Fe, Co among the inevitable impurities is less than 100 massppm, and the X-ray diffraction intensity from the {111} plane on the material surface is I The X-ray diffraction intensity from the {111}, {200} plane is I {200}, the X-ray diffraction intensity from the {220} plane is I {220}, and the X-ray diffraction intensity from the {311} plane is I {311. }, The ratio of the X-ray diffraction intensity from the {220} plane when the X-ray diffraction intensity from the {331} plane is I {331} and the X-ray diffraction intensity from the {420} plane is I {420} R {220} I {220} / (I {111} + I {200} + I {220} + I {311} + I {331} + I {420}) is characterized by being 0.3 or more.

According to the copper alloy for electronic and electrical equipment having the above-described configuration, it contains Zr in a range of 0.01 mass% or more and less than 0.11 mass%, and Si in a range of 0.0001 mass% or more and less than 0.03 mass%. While maintaining the strength, the proof stress can be improved and the Vickers hardness can be improved.
In addition, since the total content of B, P, Ni, Cr, Ti, Fe, and Co among the inevitable impurities is limited to less than 100 massppm, Zr and Si react with these inevitable impurities and are consumed. Can be suppressed.
Furthermore, since the ratio R {220} of the X-ray diffraction intensity from the {220} plane is 0.3 or more, the crystal orientation of the material is oriented in the {220} plane, which further improves the yield strength. be able to.

Here, in the copper alloy for electronic / electric equipment of the present invention, it is preferable that Cu—Zr—Si particles containing Cu, Zr and Si are present.
In this case, the presence of Cu—Zr—Si particles can improve the yield strength without lowering the electrical conductivity. Moreover, it becomes possible to improve Vickers hardness reliably.

Moreover, the copper alloy for electronic / electrical equipment of the present invention may further contain Mg in the range of 0.001 mass% or more and less than 0.1 mass%.
In this case, the yield strength and the Vickers hardness can be further improved by the Mg added in the above range being dissolved in the copper.

Furthermore, in the copper alloy for electronic / electric equipment of the present invention, the mass ratio Zr / Si of Zr and Si is preferably in the range of 2 ≦ Zr / Si ≦ 1000.
In this case, since the mass ratio Zr / Si of Zr and Si is defined as described above, the yield strength, conductivity, and Vickers hardness can be reliably improved by the synergistic effect of Zr and Si. .

Moreover, in the copper alloy for electronic / electric equipment of the present invention, it is preferable that at least a part of the Cu—Zr—Si particles have a particle size in the range of 1 nm to 500 nm.
In this case, the presence of Cu-Zr-Si particles having a relatively small particle size in the range of 1 nm to 500 nm makes it possible to improve the proof stress while maintaining the conductivity. Moreover, it becomes possible to improve Vickers hardness reliably.

Furthermore, in the copper alloy for electronic / electric equipment of the present invention, the surface Vickers hardness is preferably 120 Hv or more.
In this case, since the surface Vickers hardness is 120 Hv or more, shear workability and wear resistance are improved, and terminals for connectors and the like, parts for electronic and electrical equipment such as relays, lead frames, bus bars, etc. It is particularly suitable as a copper alloy.

The copper alloy thin plate for electronic / electric equipment of the present invention is made of the above-mentioned rolled material of copper alloy for electronic / electric equipment, and the thickness thereof is in the range of 0.05 mm or more and 2.0 mm or less. It is said.
According to the copper alloy thin plate for electronic / electric equipment having this configuration, as described above, it is made of a copper alloy for electronic / electric equipment excellent in yield strength, electrical conductivity, and Vickers hardness, and is also excellent in shear workability. Therefore, it is particularly suitable as a material for parts for electronic and electrical equipment such as terminals such as connectors, relays, lead frames and bus bars.

The component for electronic / electrical equipment of the present invention is characterized by comprising the above-described copper alloy for electronic / electrical equipment. The electronic / electrical device parts in the present invention include terminals such as connectors, relays, lead frames, bus bars and the like.
The electronic / electric equipment component having this configuration is manufactured using a copper alloy for electronic / electric equipment having excellent proof stress, electrical conductivity, and Vickers hardness, and thus has excellent reliability.

The terminal of the present invention is characterized by comprising the above-mentioned copper alloy for electronic and electrical equipment.
The terminal having this configuration is manufactured using a copper alloy for electronic and electrical equipment having excellent proof stress, electrical conductivity, and Vickers hardness, and thus has excellent reliability.

The bus bar of the present invention is characterized by comprising the above-described copper alloy for electronic and electrical equipment.
Since the bus bar having this configuration is manufactured using a copper alloy for electronic and electrical equipment having excellent proof stress, electrical conductivity, and Vickers hardness, it is excellent in reliability.

  ADVANTAGE OF THE INVENTION According to this invention, the copper alloy for electronic / electric equipments which is excellent in yield strength, electrical conductivity, and Vickers hardness, and suitable for the components for electronic / electrical equipments, and the electronic / electrical equipment consisting of this copper alloy for electronic / electrical equipments Copper alloy thin plates, parts for electronic / electrical equipment, terminals and bus bars can be provided.

It is a flowchart of the manufacturing method of the copper alloy for electronic and electric apparatuses which is this embodiment. It is a TEM (transmission electron microscope) observation photograph (magnification 20,000 times) of the copper alloy for electronic / electrical equipment in a present Example. It is a TEM (transmission electron microscope) observation photograph (magnification 100,000 times) of the copper alloy for electronic and electrical equipment in a present Example. It is a figure which shows the result of having analyzed the composition of the particle | grains observed in FIG. 3 by EDX (energy dispersive X-ray spectroscopy).

Below, the copper alloy for electronic and electric apparatuses which is one Embodiment of this invention is demonstrated.
The copper alloy for electronic / electric equipment according to the present embodiment contains 0.01 mass% or more and less than 0.11 mass%, Zr is 0.0001 mass% or more and less than 0.03 mass%, and the balance is made of Cu and inevitable impurities. The total content of B, P, Ni, Cr, Ti, Fe, and Co among the inevitable impurities is less than 100 massppm. In addition, in the copper alloy for electronic / electrical equipment which is this embodiment, in addition to Zr and Si, you may contain Mg in 0.001 mass% or more and less than 0.1 mass%.
Furthermore, in the copper alloy for electronic / electric equipment according to the present embodiment, the mass ratio Zr / Si of Zr and Si is preferably in the range of 2 ≦ Zr / Si ≦ 1000.

And in the copper alloy for electronic and electric devices which is this embodiment, it is preferable that the Cu-Zr-Si particle containing Cu, Zr, and Si exists.
At least a part of the Cu—Zr—Si particles has a particle size in the range of 1 nm to 500 nm, specifically, a relatively fine particle size in the range of 1 nm to 500 nm. Cu—Zr—Si particles and relatively coarse Cu—Zr—Si particles having a particle size in the range of 1 μm to 50 μm.

  Further, in the copper alloy for electronic / electric equipment according to this embodiment, the X-ray diffraction intensity from the {111} plane on the material surface is I {111}, and the X-ray diffraction intensity from the {200} plane is I {200. }, The X-ray diffraction intensity from the {220} plane is I {220}, the X-ray diffraction intensity from the {311} plane is I {311}, and the X-ray diffraction intensity from the {331} plane is I {331}, When the X-ray diffraction intensity from the {420} plane is I {420}, the ratio of the X-ray diffraction intensity from the {220} plane R {220} = I {220} / (I {111} + I {200 } + I {220} + I {311} + I {331} + I {420}) is 0.3 or more.

  Furthermore, the copper alloy for electronic / electric equipment according to the present embodiment has the characteristics that the electrical conductivity is 80% IACS or more, the 0.2% proof stress is 300 MPa or more, and the surface Vickers hardness is 120 Hv or more.

  Here, the reason why the component composition, the X-ray diffraction intensity, the particle diameter of the Cu—Zr—Si particles, the conductivity, the 0.2% proof stress, and the Vickers hardness are defined as described above will be described below.

(Zr: 0.01 mass% or more and less than 0.11 mass%)
Zr is thought to cause dislocation fixation due to formation of Cu-Zr-Si particles, or a solute atmosphere or a Cottrell atmosphere formed by solid solution of Zr and Si, and the effect of improving yield strength while maintaining conductivity. It is an element having Moreover, it has the effect of improving Vickers hardness.
Here, when the content of Zr is less than 0.01 mass%, there is a possibility that the effect cannot be sufficiently achieved. On the other hand, when the content of Zr is 0.11 mass% or more, the conductivity may be significantly reduced, and it becomes difficult to form a solution, and disconnection or cracking may occur during hot working or cold working. May cause defects.

  From the above, in the present embodiment, the Zr content is set within a range of 0.01 mass% or more and less than 0.11 mass%. In order to reliably improve the proof stress while maintaining the conductivity by the formation of Cu-Zr-Si particles, or by the fixing of dislocations in a solute atmosphere or a Cottrell atmosphere formed by solid solution Zr and Si, The content is preferably 0.04 mass% or more, and more preferably 0.05 mass% or more. Further, in order to surely suppress a decrease in conductivity, defects during processing, and the like, the content of Zr is preferably set to 0.10 mass% or less.

(Si: 0.0001 mass% or more and less than 0.03 mass%)
Si is considered to cause dislocation fixation due to the formation of the above-described Cu-Zr-Si particles, or a solute atmosphere or a Cottrell atmosphere formed by solid solution Zr and Si, and improves the yield strength while maintaining the conductivity. It is an element having an effect. Moreover, it has the effect of improving Vickers hardness.
Here, when the content of Si is less than 0.0001 mass%, there is a possibility that the effect cannot be fully achieved. On the other hand, when the Si content is 0.03 mass% or more, there is a possibility that the conductivity is significantly lowered by Si dissolved in the matrix.

  From the above, in this embodiment, the Si content is set within a range of 0.0001 mass% or more and less than 0.03 mass%. In order to improve the yield strength while maintaining the conductivity by forming Cu-Zr-Si particles, or by fixing dislocations in a solute atmosphere or a Cottrell atmosphere formed by solid solution Zr and Si, The content is preferably 0.0003 mass% or more, and more preferably 0.0005 mass% or more. Moreover, in order to suppress the fall of electrical conductivity reliably, it is preferable to make content of Si into 0.025 mass% or less, and it is further more preferable to set it as 0.02 mass% or less.

(Mg: 0.001 mass% or more and less than 0.1 mass%)
Mg is an element having an effect of improving proof stress and Vickers hardness while maintaining high electrical conductivity by being dissolved in a parent phase of a copper alloy.
Here, when content of Mg is less than 0.001 mass%, there exists a possibility that the effect cannot be fully achieved. On the other hand, when the Mg content is 0.1 mass% or more, cracking is likely to occur during hot working, and the conductivity may be greatly reduced.

  From the above, in this embodiment, when further adding Mg in addition to the above-mentioned Zr and Si, the content of Mg is set in the range of 0.001 mass% or more and less than 0.1 mass%. . In addition, in order to make the above-mentioned effect effective, it is preferable that the Mg content is 0.01 mass% or more. Moreover, in order to suppress the fall of electrical conductivity reliably, it is preferable that content of Mg shall be less than 0.05 mass%.

(Inevitable impurities: 0.1 mass% or less)
Inevitable impurities include B, P, Ni, Cr, Ti, Fe, Co, O, S, C, Ag, Sn, Al, Zn, Ti, Ca, Te, Mn, Sr, Ba, Sc, and Y. , Hf, V, Nb, Ta, Mo, W, Re, Ru, Os, Se, Rh, Ir, Pd, Pt, Au, Cd, Ga, In, Li, Ge, As, Sb, Tl, Pb, Be , N, H, Hg, Tc, Na, K, Rb, Cs, Po, Bi, lanthanoid and the like. Since these inevitable impurities have the effect of reducing the electrical conductivity of the material, the total amount is preferably 0.1% by mass or less. Further, in order to reliably suppress the decrease in conductivity, the total amount of these inevitable impurities is preferably less than 0.02 mass%, and more preferably less than 0.01 mass%.

(B, P, Ni, Cr, Ti, Fe, Co: less than 100 massppm in total)
In the present embodiment, among the above inevitable impurities, the specific impurity elements such as B, P, Ni, Cr, Ti, Fe, and Co are further specified for the following reasons.
In order to obtain optimum characteristics such as proof stress, electrical conductivity, and Vickers hardness, it is necessary to appropriately control the amount of Zr and the amount of Si. Here, B and P, which react with Zr in the copper alloy to form a crystallized product, form Cu—Zr—Si particles, or dislocation in a solute atmosphere or a Cottrell atmosphere formed by solid solution Zr and Si. It is necessary to strictly manage because the effect of improving the strength and the Vickers hardness is hindered by the fixing of. Ni, Cr, Ti, Fe, Co forms a compound with Si, and also forms the above-mentioned Cu-Zr-Si particles, or dislocations in a solute atmosphere or a Cottrell atmosphere formed by solid solution Zr and Si. Will be prevented from sticking. Furthermore, these compounds serve as a starting point of fracture, and may deteriorate hot rollability and cold rollability.

  From the above, in this embodiment, the total content of B, P, Ni, Cr, Ti, Fe, and Co among unavoidable impurities is defined to be less than 100 massppm. Here, in order to suppress the consumption of Zr and Si and to ensure the formation of Cu-Zr-Si particles, or the fixing of dislocations by the solute atmosphere or the Cottrell atmosphere formed by solid solution Zr and Si, More preferably, the total content of B, P, Ni, Cr, Ti, Fe, and Co is less than 20 massppm, and the total content of B, P, Ni, Cr, Ti, Fe, and Co is less than 10 massppm. Is more preferable. Further, B and P that react with Zr in the copper alloy to form a crystallized product preferably have a total content of less than 4 massppm. The total content of Ni, Cr, Ti, Fe, and Co that form a compound with Si is more preferably less than 16 mass ppm.

(Zr / Si)
As described above, it is thought that by adding Zr and Si into Cu, Cu—Zr—Si particles are formed, or dislocation fixation is caused by a solute atmosphere or a Cottrell atmosphere formed by solid solution Zr and Si. Therefore, the proof stress can be improved while maintaining the electrical conductivity. Moreover, Vickers hardness can be improved.
Here, when the ratio Zr / Si between the content of Zr (mass%) and the content of Si (mass%) is less than 2, the content of Si is larger than the content of Zr and is excessive. There exists a possibility that electrical conductivity may fall with Si. On the other hand, when Zr / Si exceeds 1000, the content of Si is small with respect to the content of Zr, and there is a possibility that the above-described effects cannot be sufficiently achieved.

  From the above, in this embodiment, the ratio Zr / Si between the Zr content (mass%) and the Si content (mass%) is set in the range of 2 to 1000. Note that Zr / Si is preferably set to 3 or more in order to reliably suppress a decrease in conductivity. In order to improve the yield strength by forming Cu—Zr—Si particles or by fixing dislocations in a solute atmosphere or a Cottrell atmosphere formed by solid solution Zr and Si, Zr / Si is set to 500 or less. It is preferable that it is 300 or less. Most preferably, it is 100 or less.

(Ratio of X-ray diffraction intensity from {220} plane R {220})
Assuming the Schmid factor, which indicates the ease of slip system activity, by tension in the direction perpendicular to the rolling direction, the crystal orientation in the {220} plane on the plate surface is compared with other crystal orientations, and the value is Since it tends to be low, a large stress is required for deformation. Therefore, by orienting the crystal orientation of the material in the {220} plane, the strength in the direction perpendicular to the rolling direction can be improved efficiently.
Therefore, the yield strength can be improved by setting the ratio R {220} of the X-ray diffraction intensity from the {220} plane on the plate surface to 0.3 or more. Note that the ratio R {220} of the X-ray diffraction intensity from the {220} plane is preferably 0.4 or more.
On the other hand, if the ratio of the {220} plane becomes too high, the bending workability deteriorates when bending is performed in a direction perpendicular to the rolling direction, and therefore preferably 0.95 or less. More preferably, it is 0.9 or less. Most preferably, it is 0.8 or less.

(Cu-Zr-Si particles)
When Zr or Si is added to Cu, Cu-Zr-Si particles containing Cu, Zr and Si are present. In the present embodiment, as described above, as the Cu—Zr—Si particles, relatively coarse particles having a particle diameter in the range of 1 μm or more and 50 μm or less, and a particle diameter in the range of 1 nm or more and 500 nm or less. Fine particles are present.
Here, it is presumed that coarse Cu—Zr—Si particles having a particle diameter in the range of 1 μm or more and 50 μm or less were crystallized or segregated during melt casting. In addition, it is presumed that fine Cu—Zr—Si particles having a particle diameter in the range of 1 nm to 500 nm are precipitated in the subsequent heat treatment or the like.

Coarse Cu—Zr—Si particles having a particle size of 1 μm or more and 50 μm or less do not contribute to improvement in strength, but when shearing represented by press punching or the like is performed, the starting point of fracture greatly increases shearing workability. It becomes possible to improve.
On the other hand, fine Cu—Zr—Si particles having a particle diameter of 1 nm or more and 500 nm or less contribute to strength improvement and can improve yield strength while maintaining high conductivity. Moreover, Vickers hardness can be improved.

(Conductivity: 80% IACS or higher)
In the case where Zr and Si are dissolved in the Cu matrix, the electrical conductivity is greatly reduced. Therefore, in this embodiment, since the electrical conductivity is specified to be 80% IACS or more, the above-described Cu-Zr-Si particles are sufficiently present, and the improvement of the yield strength and the shear workability are ensured. It is possible to improve.
In order to ensure that the above-described effects are achieved, the conductivity is preferably 85% IACS or more, and more preferably 88% IACS or more.

(0.2% proof stress: 300 MPa or more)
When the 0.2% proof stress is 300 MPa or more in the copper alloy for electronic / electric equipment according to the present embodiment, the plastic alloy is not easily plastically deformed. Therefore, for electronic equipment such as terminals such as connectors, relays, and lead frames. Especially suitable for parts.
The 0.2% proof stress is preferably 325 MPa or more, and more preferably 350 MPa or more.

(Vickers hardness is 120Hv or more)
In the copper alloy for electronic / electric equipment according to this embodiment, the shear workability is improved when the Vickers hardness is improved. Furthermore, the difficulty of scratching the surface (wear resistance) is also improved. From the above, in this embodiment, the Vickers hardness is set to 120 Hv or more.
In addition, in order to make the above-mentioned action and effect work reliably, the Vickers hardness is more preferably 125 Hv or more.

  Next, a manufacturing method of the copper alloy for electronic / electric equipment according to the present embodiment having such a configuration will be described with reference to the flowchart shown in FIG.

(Melting / Casting Process S01)
First, components are adjusted by adding Zr and Si to a molten copper obtained by melting a copper raw material, and a molten copper alloy is melted. For addition of Zr and Si, Zr alone, Si alone, Cu—Zr master alloy, Cu—Si master alloy, or the like can be used. Moreover, you may melt | dissolve the raw material containing Zr and Si with a copper raw material.

The molten copper is preferably so-called 4NCu having a purity of 99.99 mass% or more, or so-called 5NCu having a purity of 99.999 mass% or more, or 6NCu having a purity of 99.9999 mass% or more. Further, when the molten copper alloy is melted, it is preferable to use a vacuum furnace or an atmosphere furnace having an inert gas atmosphere or a reducing atmosphere in order to suppress oxidation of Zr and Si.
Then, the copper alloy molten metal whose components are adjusted is poured into a mold to produce an ingot. In consideration of mass production, it is preferable to use a continuous casting method or a semi-continuous casting method.

(Heat treatment step S02)
Next, heat treatment is performed for homogenization and solution of the obtained ingot. By performing a heat treatment for heating the ingot to 800 ° C. or more and 1080 ° C. or less, Zr and Si are uniformly diffused in the ingot or Zr and Si are dissolved in the matrix. This heat treatment step S02 is preferably performed in a non-oxidizing or reducing atmosphere.
Although the cooling method after a heating is not specifically limited, It is preferable to employ | adopt the method that cooling rate becomes 200 degrees C / min or more, such as water quenching.

(Hot processing step S03)
Next, hot working is performed in order to increase the efficiency of rough machining and make the structure uniform. The processing method is not particularly limited, but when the final shape is a plate or strip, it is preferable to employ rolling. It is preferable to employ extrusion or groove rolling in the case of a wire or bar, and forging or pressing in the case of a bulk shape. The temperature during hot working is also not particularly limited, but is preferably in the range of 500 ° C. or higher and 1050 ° C. or lower.
In addition, the cooling method after hot working is not particularly limited, but it is preferable to employ a method in which the cooling rate is 200 ° C./min or more such as water quenching.

(Intermediate processing step S04 / Intermediate heat treatment step S05)
Further, after hot working, intermediate working or intermediate heat treatment may be added for the purpose of thorough solution, recrystallization structure or softening for improving workability.
The temperature condition in the intermediate processing step S04 is not particularly limited, but is preferably in the range of −200 ° C. to 200 ° C., which is cold processing. Further, the processing rate in the intermediate processing step S04 is appropriately selected so as to approximate the final shape. However, in order to reduce the number of intermediate heat treatment step S05 until the final shape is obtained, the processing rate is set to 20% or more. It is preferable. Moreover, it is more preferable that the processing rate is 30% or more. The plastic working method in the intermediate working step S04 is not particularly limited, and for example, rolling, wire drawing, extrusion, groove rolling, forging, pressing and the like can be employed.
The heat treatment method in the intermediate heat treatment step S05 is not particularly limited, but the heat treatment is preferably performed in a non-oxidizing atmosphere or a reducing atmosphere under conditions of 500 ° C. or higher and 1050 ° C. or lower.
Note that these intermediate processing step S04 and intermediate heat treatment step S05 may be repeatedly performed.

(Finishing process S06)
Next, the material subjected to the above steps is cut as necessary, and surface grinding is performed as necessary in order to remove an oxide film or the like formed on the surface. Then, cold working (finishing) is performed at a predetermined working rate. The temperature condition in this finishing step S06 is not particularly limited, but is preferably in the range of −200 ° C. to 200 ° C.
What is necessary is just to select a processing rate suitably according to final board thickness and final shape. Here, if the processing rate is less than 30%, the (220) plane formed by rolling cannot be sufficiently increased, and the effect of improving the yield strength may not be sufficiently obtained. Therefore, the processing rate is desirably 30% or more. More desirably, it is 40% or more, and more preferably 50% or more.
On the other hand, if the processing rate exceeds 99%, bending workability and stress relaxation resistance may be deteriorated. Therefore, the processing rate is preferably 99% or less, and more preferably 98% or less.
Here, the plastic working method in the finishing step S06 is not particularly limited, but when the final shape is a plate or strip, it is preferable to employ rolling. It is preferable to employ extrusion or groove rolling in the case of a wire or bar, and forging or pressing in the case of a bulk shape.

(Aging heat treatment step S07)
Next, an aging heat treatment is performed on the finished material obtained in the finishing step S06 in order to increase strength and conductivity. By this aging heat treatment step S07, fine Cu—Zr—Si particles having a particle size of 1 nm or more and 500 nm or less are precipitated.
Here, the heat treatment temperature is not particularly limited, but is preferably in the range of 250 ° C. or more and 600 ° C. or less in order to uniformly disperse and precipitate optimally sized Cu—Zr—Si particles. In addition, since a precipitation state can be grasped | ascertained by electrical conductivity, it is preferable to set heat processing conditions (temperature, time) suitably so that it may become predetermined | prescribed electrical conductivity.

  The finishing process S06 and the aging heat treatment S07 described above may be repeated. Further, after the aging heat treatment step S07, cold working may be performed at a working rate of 1% to 70% for shape correction and strength improvement. Further, heat treatment may be performed for refining and removal of residual strain. The cooling method after the heat treatment is not particularly limited, but it is preferable to employ a method in which the cooling rate is 200 ° C./min or more, such as water quenching.

As described above, the copper alloy for electronic / electric equipment according to the present embodiment is produced. In this copper alloy for electronic / electric equipment, the 0.2% proof stress is 300 MPa or more.
Moreover, when rolling is applied as the processing method in the finish processing step S06, a copper alloy thin plate (strip material) for electronic / electric equipment having a plate thickness of about 0.05 to 2.0 mm can be obtained. Such a thin plate may be used as it is for parts for electronic and electrical equipment, but on one or both sides of the plate, Sn plating or Ag plating with a film thickness of about 0.1 to 10 μm is applied, It is good also as a copper alloy strip with plating.
Furthermore, by using a copper alloy for electronic / electric equipment (copper alloy thin plate for electronic / electric equipment) according to the present embodiment as a raw material, for example, terminals such as connectors, relays, lead frames, Parts for electronic and electrical equipment such as bus bars are molded.

According to the copper alloy for electronic and electrical equipment of the present embodiment configured as described above, Zr is 0.01 mass% or more and less than 0.11 mass%, and Si is 0.0001 mass% or more and less than 0.03 mass%. As a result, the yield strength can be improved while maintaining the conductivity by forming Cu—Zr—Si particles, or fixing dislocations in a solute atmosphere or a Cottrell atmosphere formed by solid solution Zr and Si. In addition, the Vickers hardness can be improved.
And in the copper alloy for electronic and electrical equipment which is this embodiment, since the ratio R {220} of the X-ray diffraction intensity from the {220} plane is 0.3 or more, the crystal orientation of the material is { 220} plane, and the proof stress can be further improved.

  In addition, in the copper alloy for electronic and electrical equipment according to the present embodiment, in addition to Zr and Si, when Mg is further added in the range of 0.001 mass% to less than 0.1 mass%, By allowing Mg to be dissolved, the yield strength can be further improved while maintaining high electrical conductivity.

  In addition, since the total content of B, P, Ni, Cr, Ti, Fe and Co among the inevitable impurities is limited to less than 100 massppm, Si and Zr react with these inevitable impurities and are consumed. Yield and Vickers hardness can be reliably improved by forming Cu—Zr—Si particles, or fixing dislocations in a solute atmosphere or a Cottrell atmosphere formed by solid solution of Zr and Si.

  In this embodiment, since the mass ratio Zr / Si of Zr and Si is in the range of 2 ≦ Zr / Si ≦ 1000, the synergistic effect of Zr and Si ensures that the proof stress, conductivity , Vickers hardness can be improved. More specifically, as described above, by defining the mass ratio Zr / Si of Zr and Si, it is possible to form Cu—Zr—Si particles, or a solute atmosphere or a Cottrell atmosphere formed by solid solution Zr and Si. By fixing the dislocations, the yield strength can be improved without reducing the electrical conductivity. Moreover, it becomes possible to improve Vickers hardness reliably.

  Furthermore, in this embodiment, at least a part of the Cu—Zr—Si particles has a particle size in the range of 1 nm to 500 nm, specifically, a particle size in the range of 1 nm to 500 nm. The relatively fine particles and the relatively coarse particles having a particle size in the range of 1 μm to 50 μm exist, so that the relatively fine Cu—Zr—Si particles have high conductivity. The yield strength can be improved while maintaining the above. Moreover, Vickers hardness can be improved. Further, the relatively coarse Cu—Zr—Si particles having a particle diameter of 1 μm or more and 50 μm or less can greatly improve the shear workability.

  In this embodiment, the electrical conductivity is 80% IACS or more, the 0.2% proof stress is 300 MPa or more, and the surface Vickers hardness is 120 Hv or more. Therefore, terminals such as connectors, relays, lead frames It is particularly suitable as a copper alloy for electronic and electrical equipment parts such as bus bars.

In addition, the copper alloy thin plate for electronic and electrical equipment according to the present embodiment is made of a copper alloy for electronic and electrical equipment that is excellent in yield strength, electrical conductivity, and Vickers hardness, and is also excellent in shear workability. It is particularly suitable as a material for parts for electronic and electrical equipment such as terminals such as connectors, relays, lead frames and bus bars.
In addition, in the copper alloy thin plate for electronic / electrical equipment which gave Sn plating or Ag plating on the surface, it is applicable as a raw material of various electronic / electrical equipment parts.

  Furthermore, the electronic / electronic device parts (terminals such as connectors, relays, lead frames, bus bars, etc.) according to this embodiment are made of copper alloy for electronic / electrical devices, which has excellent strength, conductivity, and Vickers hardness. Because it is manufactured, it has excellent reliability.

As described above, the copper alloy for electronic / electric equipment, the copper alloy thin plate for electronic / electric equipment, the parts for electronic / electric equipment, the terminal, the relay, and the bus bar according to the embodiment of the present invention have been described. The present invention can be changed as appropriate without departing from the technical idea of the invention.
For example, in the above-described embodiment, an example of a method for producing a copper alloy for electronic / electric equipment has been described. However, the method for producing a copper alloy for electronic / electric equipment is not limited to the embodiment, and an existing production method. You may manufacture it, selecting a method suitably.

Below, the result of the confirmation experiment performed in order to confirm the effect of this invention is demonstrated.
A copper raw material made of high-purity copper having a purity of 99.9999 mass% or more was prepared, charged into a high-purity graphite crucible, and high-frequency melted in an atmosphere furnace having an Ar gas atmosphere. Various additive elements were added to the obtained copper melt to prepare the component composition shown in Table 1, and poured into a water-cooled copper mold to produce an ingot. The size of the ingot was about 150 mm thick, about 150 mm wide, and about 150 mm long.

  The obtained ingot was subjected to a heat treatment step of heating for 4 hours under the temperature conditions shown in Table 2 for homogenization and solution treatment in an Ar gas atmosphere, and then water quenching was performed. did. The ingot after the heat treatment was cut and surface grinding was performed to remove the oxide film. Then, hot rolling was performed at the processing rate and temperature described in Table 2, and water quenching was performed.

After performing cold rolling of 26 to 94% as an intermediate working step, heat treatment was performed at 800 to 900 ° C. for 1 minute to 1 hour using a salt bath as an intermediate heat treatment.
Cold rolling was performed as a finishing process under the conditions described in Table 2 to produce a strip with a thickness of about 0.5 mm.
And the aging heat processing was implemented with respect to the obtained strip material at the temperature described in Table 2 until it became the electrical conductivity of Table 3, and the strip material for characteristic evaluation was created.

(Processability evaluation)
As evaluation of workability, the presence or absence of the ear crack in the above-mentioned finishing process (at the time of cold rolling) was observed. “◎” indicates that no or almost no ear cracks were visually observed, “◯” indicates that small ear cracks having a length of less than 1 mm occurred, and “◯” indicates that ear cracks having a length of 1 mm or more and less than 3 mm occurred. "△" and the thing with which the big ear crack more than 3 mm in length generate | occur | produced was set to "x". “Δ” in which the length of the ear crack was 1 mm or more and less than 3 mm was determined to have no practical problem.
In addition, the length of an ear crack is the length of the ear crack which goes to the width direction center part from the width direction edge part of a rolling material. The evaluation results are shown in Table 3.

(Particle observation)
In order to confirm Cu-Zr-Si particles containing Cu, Zr, and Si, particles were observed using a transmission electron microscope (TEM: JEOL Ltd., JEM-2010F), and EDX analysis (energy dispersive X Line spectroscopy).
First, as shown in FIG. 2, it observed by 20,000 times (observation visual field: 2 * 10 < ⁷ > nm < ² >) using TEM. Then, the observed particles were observed 100,000 times (observation field: 7 × 10 ⁵ nm ² ) as shown in FIG. Further, the particles having a particle size of less than 10 nm were further observed at 500,000 times (observation field: 3 × 10 ⁴ nm ² ).
Moreover, about the observed particle | grains, the composition was analyzed using EDX (energy dispersive X-ray spectroscopy), and it confirmed that it was a Cu-Zr-Si particle. An example of the EDX analysis result is shown in FIG.

The particle size of the Cu-Zr-Si particles is the major axis (the length of the straight line that can be drawn the longest in the grain under the condition that it does not contact the grain boundary in the middle) and the minor axis (in the direction perpendicular to the major axis, the grain boundary in the middle The average value of the length of the straight line that can be drawn the longest under the condition of not touching.
According to the structure observation, the case where Cu—Zr—Si particles having a particle diameter of 1 nm or more and 500 nm or less were observed was evaluated as “Yes”, and the case where Cu—Zr—Si particles were not observed was evaluated as “No”. The evaluation results are shown in Table 3.

(X-ray diffraction intensity)
The X-ray diffraction intensity from the {111} plane on the plate surface is I {111}, the X-ray diffraction intensity I {200} from the {200} plane, the X-ray diffraction intensity I {220} from the {220} plane, { 311} plane X-ray diffraction intensity I {311}, {331} plane X-ray diffraction intensity I {331}, {420} plane X-ray diffraction intensity I {420} Measured with
A measurement sample was collected from the strip for characteristic evaluation, and the X-ray diffraction intensity around one rotation axis was measured with respect to the measurement sample by a reflection method. Cu was used as the target, and Kα X-rays were used. Measured under the conditions of tube current 40 mA, tube voltage 40 kV, measurement angle 40 to 150 °, measurement step 0.02 °, and after removing the background of X-ray diffraction intensity in the profile of diffraction angle and X-ray diffraction intensity, The integrated X-ray diffraction intensity I obtained by combining the peaks Kα1 and Kα2 from the diffraction surface was determined.
Then, from R {220} = I {220} / (I {111} + I {200} + I {220} + I {311} + I {331} + I {420}), X from the {220} plane on the plate surface The ratio R {220} of the line diffraction intensity was calculated. In addition, the measurement site | part of the X-ray diffraction intensity was made into the center part of the sample plate width direction. The evaluation results are shown in Table 3.

(conductivity)
A test piece having a width of 10 mm and a length of 60 mm was taken from the strip for characteristic evaluation, and the electrical resistance was determined by a four-terminal method. Moreover, the dimension of the test piece was measured using the micrometer, and the volume of the test piece was calculated. And electrical conductivity was computed from the measured electrical resistance value and volume. In addition, the test piece was extract | collected so that the longitudinal direction might become perpendicular | vertical with respect to the rolling direction of the strip for characteristic evaluation. Table 3 shows the measurement results.

(Mechanical properties)
A No. 13B test piece defined in JIS Z 2241 was sampled from the strip for characteristic evaluation, and 0.2% proof stress was measured by an offset method. In addition, the test piece was extract | collected so that the tension direction of a tension test might become perpendicular | vertical with respect to the rolling direction of the strip for characteristic evaluation. The evaluation results are shown in Table 3.

(Vickers hardness)
Based on the micro Vickers hardness test method defined in JIS Z 2244, the Vickers hardness was measured at a test load of 0.98 N. The evaluation results are shown in Table 3.

(Method for measuring Zr, Si, Mg and impurity content)
Zr, Si, Mg and P of Comparative Example 5 were measured using an inductively coupled plasma emission spectrometer (ICP-AES). Other inevitable impurities were measured using a glow discharge mass spectrometer (GD-MS).

  Tables 1, 2, and 3 show the component composition, manufacturing process, and evaluation results.

In Comparative Example 1, Zr was less than the range of the present invention, and the proof stress and Vickers hardness were insufficient.
In Comparative Example 2, Zr was larger than the range of the present invention, and a large crack occurred during cold rolling. For this reason, subsequent evaluation was stopped.
In Comparative Example 3, Si was less than the range of the present invention, and the proof stress and Vickers hardness were insufficient.
In Comparative Example 4, Si was more than the range of the present invention, and the conductivity was greatly reduced.
In Comparative Example 5, the total of B, P, Ni, Cr, Ti, Fe, and Co, which are inevitable impurities, was larger than the range of the present invention, and large cracks occurred during cold rolling. For this reason, subsequent evaluation was stopped.
In Comparative Example 6, the ratio R {220} of the X-ray diffraction intensity from the {220} plane was small, and the proof stress and Vickers hardness were insufficient.

On the other hand, in the examples of the present invention, the electrical conductivity was high, and the proof stress and Vickers hardness were excellent.
From the above, according to the present invention, it is possible to provide a copper alloy for electronic / electric equipment that is excellent in yield strength, electrical conductivity, and Vickers hardness and that is particularly suitable as a material constituting electronic / electric equipment parts. confirmed.

Claims (10)

Zr is 0.01 mass% or more and less than 0.11 mass%, Si is 0.0001 mass% or more and less than 0.03 mass%, and the balance is made of Cu and inevitable impurities,
Of the inevitable impurities, the total content of B, P, Ni, Cr, Ti, Fe, Co is less than 100 massppm,
The X-ray diffraction intensity from the {111} plane on the material surface is I {111}, the X-ray diffraction intensity from the {200} plane is I {200}, and the X-ray diffraction intensity from the {220} plane is I {220}. , The X-ray diffraction intensity from the {311} plane is I {311}, the X-ray diffraction intensity from the {331} plane is I {331}, and the X-ray diffraction intensity from the {420} plane is I {420} The ratio of X-ray diffraction intensity from the {220} plane R {220} = I {220} / (I {111} + I {200} + I {220} + I {311} + I {331} + I {420} ) Is 0.3 or more, a copper alloy for electronic and electrical equipment.   It has Cu-Zr-Si particle | grains containing Cu, Zr, and Si, The copper alloy for electronic and electrical equipment of Claim 1 characterized by the above-mentioned.   Furthermore, Mg is contained in 0.001 mass% or more and less than 0.1 mass%, The copper alloy for electronic and electrical apparatuses of Claim 1 or Claim 2 characterized by the above-mentioned.   The mass ratio Zr / Si between Zr and Si is in the range of 2 ≦ Zr / Si ≦ 1000, for an electronic / electric device according to any one of claims 1 to 3. Copper alloy.   5. The electronic / electric device according to claim 2, wherein at least a part of the Cu—Zr—Si particles have a particle diameter in a range of 1 nm to 500 nm. Copper alloy for equipment.   6. The copper alloy for electronic and electrical equipment according to claim 1, wherein the surface has a Vickers hardness of 120 Hv or more.   It consists of a rolled material of the copper alloy for electronic / electrical devices as described in any one of Claims 1-6, The plate | board thickness is made into the range of 0.05 mm or more and 2.0 mm or less. Copper alloy sheet for electronic and electrical equipment.   An electronic / electric equipment component comprising the copper alloy for electronic / electric equipment according to any one of claims 1 to 6.   A terminal comprising the copper alloy for electronic / electric equipment according to any one of claims 1 to 6.   A bus bar comprising the copper alloy for electronic / electric equipment according to any one of claims 1 to 6.