JP6464743B2 - Copper alloy for electronic and electrical equipment, copper alloy sheet for electronic and electrical equipment, electronic and electrical equipment components, and terminals - Google Patents

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 thin plate, electronic / electric equipment parts, and terminals.

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.

  Also, for example, parts for electronic and electrical devices such as connectors are generally formed into a predetermined shape by punching a thin plate (rolled plate) having a thickness of about 0.05 to 2.0 mm, and bent to at least a part thereof. Manufactured by processing. In this case, it is used to contact the mating conductive member near the bent portion to obtain an electrical connection with the mating conductive member, and to maintain the contact state with the mating conductive material due to the spring property of the bent portion. . The materials constituting such electronic / electric equipment parts are required to have excellent bending workability, high strength, and excellent stress relaxation properties.

  Here, Cu-Mg-P alloy is used in Patent Document 1 and Cu-Mg-P alloy is used in Patent Documents 2 and 3 as materials used for electronic and electrical equipment components such as terminals such as connectors, relays, lead frames, and bus bars. -Ni-Sn-P alloys have been proposed.

Japanese Patent Publication No. 03-079417 JP 2006-213999 A JP 2006-342389 A

Recently, electronic and electrical devices have been further reduced in size and weight. Here, in the small terminal used for electronic and electrical equipment that has been reduced in size and weight, from the viewpoint of the yield of the material, a large bending process is performed so that the bending axis is orthogonal to the rolling direction, In the bending process in which the bending axis is parallel to the rolling direction, it is formed by slightly deforming, and the spring property is improved by the material strength TS _TD when the tensile test is performed in the direction orthogonal to the rolling direction. Secured. In other words, there is a demand for high strength in a direction orthogonal to the rolling direction, as well as excellent bending workability when bending so that the bending axis is orthogonal to the rolling direction.

  The present invention has been made in view of the above-described circumstances, and is excellent in bending workability when being bent so that the bending axis is orthogonal to the rolling direction, and also in the direction orthogonal to the rolling direction. It is an object of the present invention to provide a copper alloy for electronic / electric equipment, a copper alloy thin plate for electronic / electric equipment, a component for electronic / electric equipment, and a terminal having high strength.

In order to solve the above-described problems, the copper alloy for electronic / electrical equipment of the present invention includes one or two of Mg and Ni in a total amount of 0.5 mass% to 3.0 mass%, and P of 0.0. 001 mass% or more and 0.1 mass% or less, with the balance being composed of Cu and inevitable impurities, the strength TS _TD when a tensile test is performed in the direction orthogonal to the rolling direction, and the rolling direction The strength ratio TS _TD / TS _LD calculated from the strength TS _LD when the tensile test is performed in the parallel direction is characterized by exceeding 1.05.

According to the copper alloy for electronic / electrical equipment having the above-described configuration, one or two of Mg and Ni are added in a total amount of 0.5 mass% to 3.0 mass%, and P is 0.001 mass% to 0.1 mass%. %, The strength can be effectively improved by processing.
The strength ratio TS _TD calculated from the strength TS _TD when a tensile test is performed in a direction orthogonal to the rolling direction and the strength TS _LD when a tensile test is performed in a direction parallel to the rolling direction. Since / TS _LD is configured to exceed 1.05, it has excellent bending workability when bent so that the bending axis is orthogonal to the rolling direction, and with respect to the rolling direction. Thus, the strength TS _TD when the tensile test is performed in the orthogonal direction is increased. Therefore, it is excellent in the moldability of the small terminal mentioned above.

Here, in the copper alloy for electronic / electric equipment of the present invention, Zn may further be contained in a range of 2.0 mass% or less .
In this case, since Zn is contained, the heat-resistant peelability of the plating when the surface of the member made of the copper alloy is plated can be improved. Moreover, since Zn content is 2.0 mass% or less , it can suppress that a stress corrosion cracking-resistant characteristic falls. Furthermore, generation | occurrence | production of the fume at the time of casting can be suppressed, and the fall of the surface quality of an ingot can be suppressed.

Moreover, the copper alloy for electronic / electrical equipment of the present invention may further contain Sn in a range of 0.1 mass% to 2.0 mass%.
In this case, since Sn is contained by 0.1 mass% or more, the strength can be further improved. In addition, since the Sn content is 2.0 mass% or less, a decrease in conductivity can be suppressed.

Moreover, in the copper alloy for electronic / electric equipment of this invention, 1 type or 2 types in Co and Fe may be further included in 0.001 mass% or more and 0.5 mass% or less in total.
In this case, since one or two of Co and Fe are contained in total by 0.001 mass% or more, the strength can be further improved. In addition, since the total content of one or two of Co and Fe is 0.5 mass% or less, a decrease in conductivity can be suppressed.

Moreover, in the copper alloy for electronic / electrical equipment of the present invention, the CI area analyzed by the data analysis software OIM after measuring the measurement area of 1000 μm ² or more by the EBSD method at a measurement interval of 0.1 μm step is measured. When analysis is performed excluding measurement points that are 0.1 or less, the average value of the aspect ratio b / a represented by the major axis a and the minor axis b of the crystal grain size is preferably 0.6 or less.
In this case, since the average value of the aspect ratio b / a represented by the major axis a and the minor axis b of the crystal grain size is 0.6 or less, the bending axis is perpendicular to the rolling direction. Therefore, the bending workability when bent into the shape is improved. For this reason, even if it has a high distortion, excellent bending workability can be ensured, and a copper alloy excellent in strength-bending balance can be provided.

Note that the EBSD method means an electron beam diffraction diffraction pattern (EBSD) method using a scanning electron microscope with a backscattered electron diffraction image system, and the OIM uses crystal data measured by the EBSD method. It is data analysis software (Orientation Imaging Microscopy: OIM) for analyzing the azimuth. Further, the CI value is a reliability index, which is displayed as a numerical value representing the reliability of crystal orientation determination when analyzed using analysis software OIM Analysis (Ver. 5.3) of an EBSD device. (For example, “EBSD Reader: Using OIM (Revised 3rd Edition)” written by Seiichi Suzuki, September 2009, published by TSL Solutions, Inc.).
Here, when the structure of the measurement point measured by the EBSD method and analyzed by the OIM is a processed structure, since the crystal pattern is not clear, the reliability of determining the crystal orientation is lowered and the CI value is lowered. In particular, when the CI value is 0.1 or less, it is determined that the structure of the measurement point is a processed structure.

Further, in the copper alloy for electronic and electrical equipment of the present invention, 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}, 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 ratio R {220} of the X-ray diffraction intensity from the {220} plane is R When {220} = I {220} / (I {111} + I {200} + I {220} + I {311}), R {220} is preferably 0.5 or more.
In this case, the ratio R {220} of the X-ray diffraction intensity from the {220} plane on the plate surface is 0.5 or more, and there are many {220} planes on the plate surface. The formation of the {220} plane is due to the rolling texture, and the orientation relationship in which the sliding system is likely to be active with respect to the stress direction when bending is performed so that the bending axis is orthogonal to the rolling direction. Become. For this reason, even if it has a high distortion, excellent bending workability can be ensured, and a copper alloy excellent in strength-bending balance can be provided.

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 / electrical equipment of this configuration, since it is composed of the above-mentioned copper alloy for electronic / electrical equipment, by bending the copper alloy thin plate for electronic / electrical equipment, In addition, it is possible to manufacture terminals for electronic devices such as connectors, relays, lead frames, bus bars, and the like having excellent characteristics.

Here, in the copper alloy thin plate for electronic / electric equipment of the present invention, it is preferable that Sn plating or Ag plating is applied to the surface.
In this case, since Sn plating or Ag plating is applied to the surface, it is particularly suitable as a material for electronic / electric equipment parts such as terminals such as connectors, relays, lead frames, bus bars, and the like.

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 / electrical equipment component having this configuration is manufactured using the above-described copper alloy for electronic / electrical equipment, 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.
Since the terminal of this structure is manufactured using the above-mentioned copper alloy for electronic / electric equipment, it is excellent in reliability.

  ADVANTAGE OF THE INVENTION According to this invention, it is excellent in bending workability when bending so that the bending axis may be orthogonal to the rolling direction, and has high strength in the direction orthogonal to the rolling direction. Alloys, copper alloy thin plates for electronic / electrical equipment, electronic / electrical equipment parts and terminals can be provided.

It is a flowchart of the manufacturing method of the copper alloy for electronic and electric apparatuses which is this embodiment.

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 is a total of 0.5 mass% to 3.0 mass% of one or two of Mg and Ni, and P is 0.001 mass% to 0.1 mass%. Hereafter, it has a composition which contains and the remainder consists of Cu and inevitable impurities.
In addition, in the copper alloy for electronic / electrical equipment which is this embodiment, Zn is less than 3 mass%, Sn is 0.1 mass% or more and 2.0 mass% or less, and 1 type or 2 types of Co and Fe are total. It may be included in the range of 0.001 mass% to 0.5 mass%.

And in the copper alloy for electronic and electric apparatuses which is this embodiment, not only the component composition is adjusted as mentioned above, but also the characteristics and crystal structure are defined as follows.
That is, the copper alloy for electronic / electrical equipment according to the present embodiment has a strength TS _TD when a tensile test is performed in a direction orthogonal to the rolling direction and a tensile test in a direction parallel to the rolling direction. The intensity ratio TS _TD / TS _LD calculated from the intensity TS _LD exceeds 1.05 (TS _TD / TS _LD > 1.05).

Furthermore, in the copper alloy for electronic and electrical equipment according to the present embodiment, CI measured by measuring 10 or more points at a measurement interval of 0.1 μm with a measurement interval of 1000 μm ² by the EBSD method and analyzed by the data analysis software OIM. When analysis is performed excluding measurement points where the value is 0.1 or less, the average value of the aspect ratio b / a represented by the major axis a and the minor axis b of the crystal grain size is 0.6 or less.

  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 ratio R {220} of the X-ray diffraction intensity from the {220} plane Is R {220} = I {220} / (I {111} + I {200} + I {220} + I {311}), R {220} is 0.5 or more.

Also, electrical and electronic equipment for copper alloy is present embodiment, the strength TS _TD when performing the tensile direction orthogonal test to the rolling direction is more than 400 MPa, a conductivity 20% IACS or more, with respect to rolling direction The bending workability R / t when the perpendicular direction is the bending axis is 1 or less, and the residual stress ratio after holding at 180 ° C. for 24 hours is 50% or more.

  Here, the reasons for defining the component composition, the intensity ratio, the crystal grain aspect ratio, the X-ray diffraction intensity, the strength, the electrical conductivity, the bending workability, and the residual stress ratio as described above will be described below.

(Mg, Ni: 0.5 mass% to 3.0 mass% in total)
Mg and Ni are elements having an effect of greatly improving the strength when added together with P described later.
Here, when the total content of Mg and Ni is less than 0.5 mass%, there is a possibility that the function and effect cannot be fully achieved. On the other hand, when the total content of Mg and Ni exceeds 3.0 mass%, the conductivity may be significantly reduced.

  From the above, in this embodiment, the total content of Mg and Ni is set within a range of 0.5 mass% or more and 3.0 mass% or less. In order to surely improve the strength, the total content of Mg and Ni is preferably 0.55 mass% or more, more preferably 0.60 mass% or more. Further, in order to reliably suppress the decrease in conductivity, the total content of Mg and Ni is preferably 2.8 mass% or less, and more preferably 2.5 mass% or less.

(P: 0.001 mass% or more and 0.1 mass% or less)
P is an element having an effect of greatly improving the strength when added together with Mg and Ni. Moreover, it has the effect of improving castability.
Here, when content of P is less than 0.001 mass%, there exists a possibility that the effect cannot be fully achieved. On the other hand, when the content of P exceeds 0.1 mass%, the conductivity may be significantly reduced.

  From the above, in the present embodiment, the P content is set within a range of 0.001 mass% to 0.1 mass%. In order to surely improve the strength and improve the castability, the P content is preferably 0.002 mass% or more, more preferably 0.003 mass% or more. Moreover, in order to suppress the fall of electrical conductivity reliably, it is preferable to make content of P into 0.09 mass% or less, and it is further more preferable to set it as 0.08 mass% or less.

(Zn: less than 3 mass%)
Since Zn has the effect of improving the heat-resistant peelability of plating, it may be added as appropriate according to the intended use. However, if the Zn content is 3 mass% or more, the stress corrosion cracking resistance may be deteriorated. Further, fumes are likely to be generated during melt casting, and the surface quality of the ingot may be deteriorated.
For this reason, when adding Zn, it is preferable to make content of Zn into less than 3 mass%, Furthermore, it is preferable to set it as 2.5 mass% or less, and it is more preferable to set it as 2.0 mass% or less.

(Sn: 0.1 mass% or more and 2.0 mass% or less)
Since Sn has the effect of further improving the strength, Sn may be appropriately added depending on the intended use.
Here, when the content of Sn is less than 0.1 mass%, there is a possibility that the effect cannot be sufficiently achieved. On the other hand, when the Sn content exceeds 2.0 mass%, the electrical conductivity may be significantly reduced.
From the above, when Sn is added, the Sn content is preferably in the range of 0.1 mass% or more and 2.0 mass% or less. In order to surely improve the strength, the Sn content is preferably set to 0.2 mass% or more, and more preferably 0.3 mass% or more. Moreover, in order to suppress the fall of electrical conductivity reliably, it is preferable to make content of Sn into 1.9 mass% or less, and it is further more preferable to set it as 1.8 mass% or less.

(Co, Fe: 0.001 mass% or more and 0.5 mass% or less in total)
Since Co and Fe have the effect of further improving the strength, they may be appropriately added depending on the intended use.
Here, when the total content of Co and Fe is less than 0.001 mass%, there is a possibility that the effect cannot be sufficiently achieved. On the other hand, when the total content of Co and Fe exceeds 0.5 mass%, the conductivity may be significantly reduced.
From the above, when Co and Fe are added, the total content of Co and Fe is preferably within the range of 0.001 mass% to 0.5 mass%. In order to surely improve the strength, the total content of Co and Fe is preferably 0.002 mass% or more, and more preferably 0.003 mass% or more. Further, in order to reliably suppress the decrease in conductivity, the total content of Co and Fe is preferably 0.48 mass% or less, and more preferably 0.45 mass% or less.

(Inevitable impurities: 0.1 mass% or less)
Inevitable impurities include B, Cr, Ti, (Fe), (Co), O, S, C, Ag, (Sn), Al, (Zn), Ca, Te, Mn, Sr, Ba, Sc. , 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, Mg, Ni, Si and the like. Since these inevitable impurities have an effect of lowering the electrical conductivity, the total amount is preferably 0.1% by mass or less.

(Intensity ratio TS _TD / TS _LD > 1.05)
When the intensity ratio TS _TD / TS _LD exceeds 1.05, there are many {220} planes in the plane perpendicular to the normal direction to the rolling plane. By increasing the {220} plane, bending workability (GW bending workability) is improved when bending is performed so that the bending axis is perpendicular to the rolling direction. Moreover, strength TS _TD (strength of BW) when a tensile test is performed in a direction orthogonal to the rolling direction is increased.

From the above, in this embodiment, the strength TS _TD when a tensile test is performed in a direction orthogonal to the rolling direction, and the strength TS _LD when a tensile test is performed in a direction parallel to the rolling direction, The intensity ratio TS _TD / TS _LD calculated from is set to exceed 1.05.
The intensity ratio TS _TD / TS _LD is preferably 1.06 or more, and more preferably 1.07 or more. Further, the intensity ratio TS _TD / TS _LD is preferably 1.25 or less, and more preferably 1.20 or less.

(Aspect ratio of crystal grains of 0.6 or less)
When the major axis of the crystal grain size is a and the minor axis is b, the aspect ratio represented by b / a is an index representing the degree of processing of the material, and crystal grains having a small aspect ratio (that is, major axis a and short axis). The degree of processing increases as the ratio of the crystal grains having a large difference from the diameter b increases. When the average value of the aspect ratio b / a is 0.6 or less, the bending workability when bending is performed so that the bending axis is perpendicular to the rolling direction is improved. . Further, the strength in the direction orthogonal to the rolling direction is improved by the processing.
From the above, in this embodiment, the average value of the aspect ratio b / a of the crystal grains is set to be 0.6 or less. The average value of the aspect ratio b / a of the crystal grains is preferably 0.55 or less, and more preferably 0.50 or less.

In the present embodiment, measurement points with a measurement area of 1000 μm ² or more measured by the EBSD method at 10 or more points at a measurement interval of 0.1 μm and a CI value analyzed by the data analysis software OIM is 0.1 or less. And the above aspect ratio is calculated. Here, the CI value (reliability index) when analyzed by the analysis software OIM of the EBSD device becomes smaller when the crystal pattern of the measurement point is not clear, and the analysis is performed when the CI value is 0.1 or less. It is difficult to trust the results. Therefore, in the present embodiment, measurement points with low reliability whose CI value is 0.1 or less in the aspect ratio evaluation are excluded.

(Ratio of X-ray diffraction intensity from {220} plane R {220})
The formation of the {220} plane is due to the rolling texture, and the orientation is such that the sliding system is easy to activate in the bending stress direction so that the bending axis is perpendicular to the rolling direction. For this reason, when there are many {220} planes on the plate surface, the bending workability when bending is performed so that the bending axis is perpendicular to the rolling direction is improved.
In addition, assuming a Schmid factor indicating the ease of sliding system activity by tension in a direction perpendicular to the rolling direction, the crystal orientation oriented in the {220} plane on the plate surface is compared with other crystal orientations, Since the value 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 orthogonal to the rolling direction can be improved efficiently.

For this reason, in this embodiment, by setting the ratio R {220} of the X-ray diffraction intensity from the {220} plane on the plate surface to be 0.65 or more, the bending axis is perpendicular to the rolling direction. Thus, the bending workability when bending is improved, and the strength (TS _TD ) in the direction orthogonal to the rolling direction is improved.
Here, in order to ensure that the above-described effects are achieved, the ratio R {220} of the X-ray diffraction intensity from the {220} plane on the plate surface is preferably 0.70 or more, and 0.80 or more. More preferably.

(TS _TD : 400 MPa or more)
In the copper alloy for electronic and electrical equipment according to the present embodiment, the spring property can be ensured by setting the strength TS _TD when the tensile test is performed in the direction orthogonal to the rolling direction to 400 MPa or more. It is particularly suitable as a part for electronic and electrical equipment such as terminals, relays, lead frames and the like.
The strength TS _TD when a tensile test is performed in a direction orthogonal to the rolling direction is preferably 425 MPa or more, and more preferably 450 MPa or more.

(Conductivity: 20% IACS or higher)
In the copper alloy for electronic and electrical equipment according to this embodiment, by setting the conductivity to 20% IACS or higher, it can be used favorably as a part for electronic and electrical equipment such as terminals of connectors, relays, lead frames, etc. Can do.
The conductivity is preferably 30% IACS or more, and more preferably 40% IACS or more.

(GW bending workability R / t: 1 or less)
In the copper alloy for electronic and electrical equipment according to the present embodiment, the bending workability R / t when the bending process is performed so that the bending axis is perpendicular to the rolling direction is set to 1 or less. The bending workability is ensured, and it becomes easy to mold the parts for electronic and electrical equipment such as terminals such as connectors, relays, and lead frames by the bending work.
The bending workability R / t when bending is performed so that the bending axis is perpendicular to the rolling direction is preferably 0.90 or less, and more preferably 0.80 or less. . More preferably, it is 0.70 or less.

(Residual stress ratio: 50% or more)
In the copper alloy for electronic devices according to this embodiment, by setting the residual stress rate after holding at 180 ° C. for 24 hours to 50% or more, the permanent deformation can be kept small even when used in a high temperature environment. And a decrease in contact pressure can be suppressed. Therefore, the copper alloy for electronic / electric equipment according to the present embodiment can be applied as a terminal used in a high temperature environment such as around the engine room of an automobile.
Note that the residual stress ratio after holding at 180 ° C. for 24 hours is preferably 60% or more, and more preferably 70% 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, the above-described elements are added to a molten copper obtained by melting a copper raw material to adjust the components, thereby producing a molten copper alloy. In addition, an element simple substance, a mother alloy, etc. can be used for the addition of various elements. Moreover, you may melt | dissolve the raw material containing the above-mentioned element with a copper raw material. Moreover, you may use the recycling material and scrap material of this alloy. Here, the molten copper is preferably so-called 4NCu having a purity of 99.99 mass% or more. In addition, an atmospheric furnace may be used for melting, but an atmosphere furnace having a vacuum furnace, an inert gas atmosphere, or a reducing atmosphere may be used in order to suppress oxidation of the additive element.
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 heating the ingot, the additive element is uniformly diffused in the ingot, or the additive element is dissolved in the matrix.
Here, in the heat treatment step S02, the heat treatment method is not particularly limited, but a non-oxidizing atmosphere is maintained at a holding temperature of 400 ° C. to 900 ° C. and a holding time of 1 hour to 10 hours in order to suppress the formation of precipitates. Or it is preferable to carry out in a reducing atmosphere. Moreover, the cooling method after heating is not particularly limited, but it is preferable to adopt a method such as water quenching in which the cooling rate is 200 ° C./min or more.
Furthermore, hot processing may be performed after the heat treatment in order to increase the efficiency of rough processing and make the structure uniform. Although a processing method is not specifically limited, For example, rolling, wire drawing, extrusion, groove rolling, forging, pressing, etc. are employable. In addition, when the final shape is a plate or a strip, it is preferable to employ rolling. Moreover, the temperature at the time of hot working is not particularly limited, but is preferably in the range of 400 ° C. or more and 900 ° C. or less.

(First intermediate processing step S03)
Next, the material after the heat treatment step S02 is cut as necessary, and surface grinding is performed as necessary to remove oxide scales and the like. Thereafter, plastic working is performed into a predetermined shape.
The temperature condition in the first intermediate processing step S03 is not particularly limited, but is preferably in the range of −200 ° C. to 200 ° C. that is cold or warm processing. The processing rate is appropriately selected so as to approximate the final shape, but is preferably 30% or more, more preferably 35% or more, and further preferably 40% or more. . The plastic working method is not particularly limited, and for example, rolling, wire drawing, extrusion, groove rolling, forging, pressing, and the like can be employed.

(First intermediate heat treatment step S04)
After the first intermediate processing step S03, heat treatment is performed for the purpose of thorough solutionization, recrystallization texture formation, or softening for improving workability.
The heat treatment method is not particularly limited, but the heat treatment is preferably performed in a non-oxidizing atmosphere or a reducing atmosphere at a holding temperature of 400 ° C. to 900 ° C. and a holding time of 10 seconds to 10 hours. Moreover, the cooling method after heating is not particularly limited, but it is preferable to adopt a method such as water quenching in which the cooling rate is 200 ° C./min or more.

(Second intermediate machining step S05)
Surface grinding is performed as necessary to remove the oxide scale and the like generated in the first intermediate heat treatment step S04. Then, plastic working is performed into a predetermined shape.
The temperature condition in the second intermediate processing step S05 is not particularly limited, but is preferably in the range of −200 ° C. to 200 ° C. that is cold or warm processing. The processing rate is appropriately selected so as to approximate the final shape, but is preferably 20% or more, and more preferably 30% or more. The plastic working method is not particularly limited, and for example, rolling, wire drawing, extrusion, groove rolling, forging, pressing, and the like can be employed.

(Second intermediate heat treatment step S06)
After the second intermediate processing step S05, heat treatment is performed for the purpose of thorough solutionization, recrystallization texture formation, or softening for improving workability.
The heat treatment method is not particularly limited, but the heat treatment is preferably performed in a non-oxidizing atmosphere or a reducing atmosphere at a holding temperature of 400 ° C. to 900 ° C. and a holding time of 10 seconds to 10 hours. Moreover, the cooling method after heating is not particularly limited, but it is preferable to adopt a method such as water quenching in which the cooling rate is 200 ° C./min or more.

  In order to make the crystal grains uniform, the second intermediate processing step S05 and the second intermediate heat treatment step S06 may be repeatedly performed. In order to improve the bending workability and stress relaxation resistance of the final product, it is preferable to repeat the second intermediate processing step S05 and the second intermediate heat treatment step S06 two or more times.

(Finishing process S07)
The copper material after the second intermediate heat treatment step S06 is finished into a predetermined shape. In addition, although the temperature conditions in this finishing process S07 are not specifically limited, in order to suppress precipitation, it is preferable to set it in the range of -200 degreeC to 200 degreeC used as a cold or warm process. Further, the processing rate (rolling rate) is appropriately selected so as to approximate the final shape. In the above-described intermediate processing step (first intermediate processing step S03 and second intermediate processing step S05) and intermediate heat treatment step (first intermediate heat treatment step S04 and second intermediate heat treatment step S06), the crystal grains are uniformized and finished. By increasing the working rate (rolling rate) in step S07, the strength ratio TS _TD / TS _LD becomes 1.05 or more, and as a result, bending workability and stress relaxation resistance are improved. Therefore, the processing rate (rolling rate) in the finish processing step S07 is preferably 40% or more, further preferably 45% or more, and more preferably 50% or more.

(Low-temperature annealing step S08)
Next, low-temperature annealing is performed on the copper material obtained in the finishing process S07.
The low-temperature annealing conditions are preferably a non-oxidizing atmosphere or a reducing atmosphere within a range where the holding temperature is 200 ° C. or higher and 800 ° C. or lower. The holding time is preferably set as appropriate according to the holding temperature. For example, it is preferably about 1 minute to 24 hours at 200 ° C. and about 1 second to 10 seconds at 400 ° C. Moreover, the cooling method after heating is not particularly limited, but it is preferable to adopt a method such as water quenching in which the cooling rate is 60 ° C./min or more.
The finishing process S07 and the low-temperature annealing process S08 described above may be repeated a plurality of times.

In this way, the copper alloy for electronic / electric equipment and the copper alloy thin plate for electronic / electric equipment according to the present embodiment are produced. In addition, the copper alloy thin plate for electronic / electric equipment has a plate thickness of about 0.05 to 2.0 mm. This copper alloy thin plate for electronic / electric equipment may be used as it is for parts for electronic / electric equipment, but Sn plating or Ag with a film thickness of about 0.1 to 10 μm on one or both sides of the plate surface. It is good also as a copper alloy strip with plating by 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 / electric equipment according to the present embodiment configured as described above, a total of one or two of Mg and Ni is 0.5 mass% to 3.0 mass%, P Is contained in the range of 0.001 mass% to 0.1 mass%, so that the strength can be effectively improved by processing.
The strength ratio TS _TD calculated from the strength TS _TD when a tensile test is performed in a direction orthogonal to the rolling direction and the strength TS _LD when a tensile test is performed in a direction parallel to the rolling direction. Since / TS _LD exceeds 1.05, it has excellent bending workability when bent so that the bending axis is orthogonal to the rolling direction, and is orthogonal to the rolling direction. Strength TS _{TD at} the time of performing a tensile test is increased.

  Moreover, in the copper alloy for electronic / electrical equipment which is this embodiment, when Zn is further contained in the range of less than 3 mass%, the heat-resistant peelability of plating can be improved. In addition, since the Zn content is regulated to be less than 3 mass%, it is possible to suppress the deterioration of the stress corrosion cracking resistance and the surface quality of the ingot.

In addition, in the copper alloy for electronic and electrical equipment according to this embodiment, when Sn is further included in the range of 0.1 mass% or more and 2.0 mass% or less, the strength is further reduced without greatly reducing the conductivity. Improvements can be made.
Furthermore, in the copper alloy for electronic / electrical equipment which is this embodiment, when 1 type or 2 types in Co and Fe are further included in the range of 0.001 mass% or more and 0.5 mass% or less in total. Further, the strength can be further improved without greatly reducing the conductivity.

In the copper alloy for an electrical and electronic equipment is the embodiment, a 1000 .mu.m ² or more measurement area measured 10 or more places in the measurement interval 0.1μm step by EBSD method, analyzed by the data analysis software OIM CI When the analysis is performed except for the measurement point where the value is 0.1 or less, the average value of the aspect ratio b / a represented by the major axis a and the minor axis b of the crystal grain size is 0.6 or less. Bending workability when bending so that the axis of bending is perpendicular to the rolling direction will be improved, and excellent bending workability can be ensured even with high strain, A copper alloy having an excellent strength-bending balance can be provided.

  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 ratio R {220} of the X-ray diffraction intensity from the {220} plane Is R {220} = I {220} / (I {111} + I {200} + I {220} + I {311}), and R {220} is 0.5 or more. The orientation of the sliding system is easy to activate with respect to the stress direction when bending is performed so that the bending axis is orthogonal to the direction, and the bending axis is orthogonal to the rolling direction. Bending workability when bending is improved. In addition, the presence of a large amount of R {220} improves the strength in the direction perpendicular to the rolling direction.

Further, in the electrical and electronic equipment for copper alloy is present embodiment, the strength TS _TD when performing the tensile direction orthogonal test to the rolling direction is more than 400 MPa, a conductivity 20% IACS or more, in the rolling direction On the other hand, the bending workability R / t when bent so that the bending axis is orthogonal is 1 or less, and the residual stress ratio after holding at 180 ° C. for 24 hours is 50% or more. It is particularly suitable as a material for electronic and electrical equipment parts such as terminals, relays, lead frames and bus bars.

Moreover, since the copper alloy thin plate for electronic / electrical equipment which is this embodiment is comprised with the above-mentioned copper alloy for electronic / electrical equipment, bending processing etc. are performed to this copper alloy thin plate for electronic / electrical equipment. Thus, it is possible to manufacture parts for electronic and electrical equipment such as terminals such as connectors, relays, lead frames, and bus bars.
Moreover, in the copper alloy thin plate for electronic / electrical equipment which carried out Sn plating or Ag plating on the surface, it is applicable as a raw material of various electronic / electrical equipment parts.

  Furthermore, since the electronic / electrical device parts (terminals such as connectors, relays, lead frames, bus bars, etc.) according to the present embodiment are composed of the above-described copper alloy for electronic / electrical devices, they are excellent in reliability. Yes.

As described above, the copper alloy for electronic / electric equipment, the copper alloy thin plate for electronic / electric equipment, the component for electronic / electric equipment, and the terminal according to the embodiment of the present invention have been described, but the present invention is not limited thereto. The 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 oxygen-free copper (ASTM B152 C10100) having a purity of 99.99 mass% or more was prepared, charged in 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 molten copper to prepare the component compositions shown in Table 1, and poured into a carbon mold to produce an ingot. The size of the ingot was about 50 mm thick × about 220 mm wide × about 50 mm long.
The vicinity of the cast surface of the ingot was chamfered, and the ingot was cut out and adjusted in size so that the final product was 0.15 mm.

The obtained ingot was subjected to a heat treatment step at a holding temperature and a holding time shown in Table 2 in an Ar gas atmosphere for homogenization and solution, and then water quenching was performed.
The material after the heat treatment was cut, and surface grinding was performed to remove the oxide scale.

  Next, as a first intermediate working step, after cold rolling was performed at a rolling rate shown in Table 2, heat treatment was performed for 4 hours at a temperature shown in Table 2 using a salt bath as a first intermediate heat treatment. In Table 2, the first intermediate processing step is indicated as “intermediate rolling 1”, and the first intermediate heat treatment step is indicated as “intermediate heat treatment 1”.

Next, as a second intermediate working step, after cold rolling was performed at a rolling rate shown in Table 2, heat treatment was performed for 1 minute at a temperature shown in Table 2 using a salt bath as a second intermediate heat treatment. In Table 2, the second intermediate processing step is indicated as “intermediate rolling 2”, and the second intermediate heat treatment step is indicated as “intermediate heat treatment 2”.
Further, as a second second intermediate processing step, after performing cold rolling at the rolling rate shown in Table 2, heat treatment for 1 minute at a temperature shown in Table 2 using a salt bath as a second second intermediate heat treatment Went. In Table 2, the second second intermediate working step is indicated as “intermediate rolling 3”, and the second second intermediate heat treatment step is indicated as “intermediate heat treatment 3”.
In Comparative Example 4, as shown in Table 2, the finish rolling rate is relatively low at 40% in a state where the second intermediate step and the second heat treatment step are not performed, and the low temperature annealing temperature is 450 ° C. did.

Next, cold rolling was performed as a finishing process under the conditions described in Table 2 to produce a strip having a thickness of about 0.15 mm, a width of 200 mm, and a length of 200 mm.
Then, the obtained strip material was subjected to low-temperature annealing that was held for 5 minutes at the temperature described in Table 2 to create a strip for property evaluation.

(aspect ratio)
The rolled surface of the strip for property evaluation, that is, the ND surface was subjected to mechanical polishing using water-resistant abrasive paper and diamond abrasive grains, and then subjected to final polishing using a colloidal silica solution. And an EBSD measuring device (Quanta FEG 450 made by FEI, EDAX / TSL (current AMETEK) OIM Data Collection) and analysis software (EDAX / TSL (current AMETEK) OIM Data Analysis ver. 5.3). ), An area of one field of view of 1200 μm 2 is measured at an electron beam acceleration voltage of 20 kV and a measurement interval of 0.1 μm, and an analysis of the orientation difference of each crystal grain is performed except for a measurement point having a CI value of 0.1 or less. When the major axis of the crystal grain size of each crystal grain is a and the minor axis is b, the b / a is expressed as b / a. The aspect ratio was measured. Here, for each field of view obtained above, the aspect ratio is 10 or more lines drawn in a direction parallel to the direction orthogonal to the rolling direction, and the major axis a and minor axis are calculated from the number of crystal grains crossing each other. b was calculated and the average b / a was calculated. 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, { The X-ray diffraction intensity I {311} from the 311} plane is measured by the following procedure. 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 is obtained, and the formula R {220} = I {220} / (I {111} + I {200} + I {220} + I {311}) Thus, the value of R {220} was obtained. The evaluation results are shown in Table 3.

(Strength)
A No. 13B test piece defined in JIS Z 2241 was taken from the strip for characteristic evaluation, and the strength was measured by an offset method. In addition, the test piece was extract | collected so that the tension direction of a tension test might be parallel and orthogonal to the rolling direction of the strip for characteristic evaluation.
Table 3 shows strength TS _TD when a tensile test is performed in a direction orthogonal to the rolling direction, strength TS _LD when a tensile test is performed in a direction parallel to the rolling direction, and strength ratio TS _TD / TS _LD. .

(conductivity)
A test piece having a width of 10 mm and a length of 150 mm was taken from the strip for characteristic evaluation, and the electric 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. The evaluation results are shown in Table 3.

(Bending workability)
Bending was performed in accordance with four test methods of Japan Copper and Brass Association Technical Standard JCBA-T307: 2007.
A plurality of test pieces having a width of 10 mm and a length of 30 mm are collected from the strip for characteristic evaluation so that the rolling direction and the longitudinal direction of the test piece are parallel (so that the bending axis is orthogonal to the rolling direction) and bent. A W-bending test was performed using a W-shaped jig having an angle of 90 degrees and a bending radius R. The evaluation was carried out with various bending radii R, and the evaluation was performed with the value of R / t, which is the ratio of the minimum bending radius R and the material thickness t, in which no crack was confirmed with an optical microscope. The evaluation results are shown in Table 3.

(Stress relaxation characteristics)
In the stress relaxation resistance test, stress was applied by a method according to the cantilever screw method of Japan Copper and Brass Association Technical Standard JCBA-T309: 2004, and the residual stress ratio after holding for a predetermined time at a temperature of 180 ° C. was measured. .
As a test method, a specimen (width 10 mm) is taken from each characteristic evaluation strip in a direction orthogonal to the rolling direction, and the initial deflection displacement is performed so that the maximum surface stress of the specimen is 80% of the proof stress. Was set to 2 mm, and the span length was adjusted. The maximum surface stress is determined by the following equation.
Maximum surface stress (MPa) = 1.5 × Et × δ ₀ / L _s ²
Where E: Young's modulus (MPa), t: sample thickness (t = 0.15 mm), δ ₀ : initial deflection displacement (2 mm), and L _s : span length (mm).
The residual stress rate was measured from the bending wrinkles after being held at a temperature of 180 ° C. for 24 hours, and the residual stress rate was evaluated. The residual stress rate was calculated using the following formula.
Residual stress rate (%) = (1−δ _t / δ ₀ ) × 100
Where δ _{t is} (permanent deflection displacement (mm) after being held at 180 ° C. for 24 hours) − (permanent deflection displacement (mm) after being held at room temperature for 24 hours), and δ ₀ is an initial deflection displacement (mm). .

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

In Comparative Example 1, the total content of Mg and Ni is less than the range of the present invention, the strength TS _TD when the tensile test is performed in the direction orthogonal to the rolling direction, and the tensile force in the direction parallel to the rolling direction. The strength TS _{LD at} the time of the test was low, and the strength ratio TS _TD / TS _LD was insufficient at 1.02.
In Comparative Example 2, the total content of Mg and Ni was larger than the range of the present invention, and the conductivity was relatively low.
In Comparative Example 3, the P content was larger than the range of the present invention, and the conductivity was relatively low.
Comparative Example 4 is a strength calculated from a strength TS _TD when a tensile test is performed in a direction orthogonal to the rolling direction and a strength TS _LD when a tensile test is performed in a direction parallel to the rolling direction. The ratio TS _TD / TS _LD is 1.01, the bending workability R / t when bending so that the bending axis is perpendicular to the rolling direction is as large as 1.50, and the GW Bending workability was insufficient.

On the other hand, in the example of the present invention, the bendability R / t when the bending is performed so that the conductivity is relatively high and the bending axis is perpendicular to the rolling direction is good. It was. Further, the strength TS _TD when the tensile test was performed in the direction orthogonal to the rolling direction was sufficiently high.
From the above, according to the present invention, an electron having excellent bending workability when bent so that the axis of bending is perpendicular to the rolling direction and having high strength in the direction perpendicular to the rolling direction. -It was confirmed that copper alloys for electrical equipment and copper alloy sheets for electronic and electrical equipment can be provided.

Claims (10)

One or two of Mg and Ni are combined in a total amount of 0.5 mass% to 3.0 mass%, P is contained in an amount of 0.001 mass% to 0.1 mass%, with the balance being Cu and inevitable impurities. Have
Strength ratio TS _TD / TS calculated from strength TS _TD when a tensile test is performed in a direction orthogonal to the rolling direction and strength TS _LD when a tensile test is performed in a direction parallel to the rolling direction _A copper alloy for electronic and electrical equipment characterized by an _LD exceeding 1.05. Furthermore, Zn is contained in 2.0 mass% or less of range, The copper alloy for electronic and electrical equipment of Claim 1 characterized by the above-mentioned.   Furthermore, Sn is contained in the range of 0.1 mass% or more and 2.0 mass% or less, The copper alloy for electronic and electrical equipment of Claim 1 or Claim 2 characterized by the above-mentioned.   Furthermore, 1 type or 2 types in Co and Fe are included in the range of 0.001 mass% or more and 0.5 mass% or less in total, The Claim 1 characterized by the above-mentioned. Copper alloy for electronic and electrical equipment. When the measurement area of 1000 μm ² or more is measured by the EBSD method at 10 or more points at a measurement interval of 0.1 μm, and the analysis is performed except for the measurement points where the CI value analyzed by the data analysis software OIM is 0.1 or less, 5. The electron according to claim 1, wherein the average value of the aspect ratio b / a represented by the major axis “a” and the minor axis “b” of the crystal grain size is 0.6 or less. -Copper alloy for electrical equipment.   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}, and the ratio R {220} of the X-ray diffraction intensity from the {220} plane is R {220} = I {220} / (I {111} + I 6. The electron according to claim 1, wherein R {220} is 0.5 or more when {200} + I {220} + I {311}). Copper alloy for electrical equipment.   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.   The copper alloy thin plate for electronic / electric equipment according to claim 7, wherein Sn plating or Ag plating is applied to the surface.   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.

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