JP6265651B2 - Copper alloy sheet, connector using the same, and method for producing the copper alloy sheet - Google Patents

Description

  The present invention relates to a copper alloy plate material, a connector using the copper alloy plate material, and a method for manufacturing the copper alloy plate material, and more particularly to a lead frame, a connector, a terminal material, a relay, a switch, a socket, etc. The present invention relates to a copper alloy sheet material applied to the above, a connector using the same, and a method for producing the copper alloy sheet material.

  With recent miniaturization of electrical and electronic equipment, miniaturization of terminals and contact parts is progressing. For example, in the electrical contact, when the shape of the member constituting the spring is reduced, the spring length is shortened, so that the load stress on the spring copper alloy is increased. If the stress becomes higher than the yield point of the copper alloy material, the material is permanently deformed, and a desired contact pressure cannot be obtained as a spring. In that case, the contact resistance increases, and the electrical connection becomes insufficient, which becomes a serious problem. Therefore, the copper alloy is required to have high strength and high yield strength.

  In recent years, as the price of copper has risen, in order to reduce material loss when a terminal is punched from a copper strip by press working, material is taken in the direction of rolling direction (Transverse Direction; TD). Accordingly, it is necessary to improve the yield strength (YS (TD)) in the vertical direction of rolling of the copper alloy sheet.

Furthermore, since each of the terminals is downsized, a cross-sectional area to be energized is reduced, and a desired current value cannot be supplied. For example, phosphor bronze can be cited as a general copper alloy as a terminal material. However, when a high-strength component composition is used, the conductivity is around 10% IACS, which is insufficient for a small terminal. In addition, since the heat capacity is reduced when the electronic device is downsized, if the Joule heat generation of the conductor is large, the temperature of the entire device is directly increased, which causes a problem. Accordingly, the copper alloy is required to have good conductivity.
However, the above high strength (for example, high yield strength) and good electrical conductivity are contradictory properties. In contrast, conventionally, attempts have been made to achieve high strength and good conductivity with various copper alloys.

Patent Document 1 proposes that a copper alloy having high strength and good fatigue characteristics can be obtained by selecting components of a Cu-Ni-Sn alloy and age-hardening and hardening in a specific process.
Patent Document 2 proposes adjusting the crystal grain size and finish rolling conditions of a Cu-Sn alloy to obtain a high-strength copper alloy.
In patent document 3, it is proposed to make it high intensity | strength by preparing in a specific process in the case of high density | concentration among Cu-Ni-Si type alloys.
In Patent Document 4, it is proposed to select a component of the Cu—Ti alloy and to increase the strength by age-precipitation hardening in a specific process.

Japanese Unexamined Patent Publication No. Sho 63-312937 JP 2002-294367 A JP 2006-152392 A JP 2011-132594 A

By the way, in patent documents 1-4, although high intensity | strength is acquired compared with the general copper alloy, depending on an alloy system and a manufacturing method, electrical conductivity may still be low, and it has become especially important in recent years. The yield strength in the vertical direction of rolling has not been sufficiently increased.
Therefore, a copper alloy material having high yield strength while having good conductivity is required.

  In view of the problems as described above, an object of the present invention is to provide a copper alloy sheet material that achieves both high yield strength in the vertical direction of rolling of the copper alloy sheet material and good electrical conductivity, a connector using the copper alloy sheet material, and a method for manufacturing the same. It is to provide. In particular, it is an object of the present invention to provide a copper alloy sheet material suitable for connectors and terminal materials for lead frames, relays, switches, automobiles and the like for electric and electronic devices, a connector using the same, and a manufacturing method thereof.

  As a result of intensive studies to solve the above problems, the present inventors satisfy a predetermined X-ray diffraction intensity ratio obtained by X-ray diffraction rocking curve measurement, and suppress second-phase particles having a predetermined size. Thus, it has been found that a copper alloy sheet material having both high yield strength in the vertical direction of rolling and good electrical conductivity can be obtained by controlling the metal structure from both the crystal orientation and the structure. The present invention has been completed based on this finding.

That is, the said subject is solved by the following means.
(1) One or two of Ni and Co in total 1.8 to 6.0 mass%, Si 0.4 to 1.6 mass%, and Sn 0 to 1.95 mass% Zn is 0 to 1.92 mass%, Mn is 0 to 0.15 mass%, P is 0 to 0.05 mass%, Mg is 0 to 0.15 mass%, and Cr is 0 to 0.15 mass%. , 0 to 0.06 mass% of Zr, and 0 to 2.0 mass% in total of at least one element selected from the group consisting of 0 to 0.23 mass% of Fe, with the balance being copper and inevitable A copper alloy sheet having an alloy composition consisting of impurities,
In the metal structure of the copper alloy plate material, the second phase having a particle diameter of 20 nm or more is included at a density of 15 pieces / μm ² or less,
In the X-ray diffraction measurement of the {220} plane of the parent phase of the copper alloy plate having an inclination of φ (°) from the rolling surface with the rolling direction of the copper alloy plate as the rotation axis, φ = 0 (°) and φ = 30 (°) der _R = I 0 _{/ I 30} 20 or more which is the ratio of the diffraction intensity _{I 0} and _{I 30} when the is,
Copper alloy sheet yield strength in the rolling vertical direction of the copper alloy sheet is characterized in der Rukoto than 1020 mPa.
(2) 0 to 1.95 mass% of Sn, 0 to 1.92 mass% of Zn, 0 to 0.15 mass% of Mn, 0 to 0.05 mass% of P, and 0 to 0.15 of Mg 0.005 in total of at least one element selected from the group consisting of 0% by mass, 0.1% by mass of Cr, 0-0.06% by mass of Zr, and 0-0.23% by mass of Fe. The copper alloy sheet according to item (1), which is contained in an amount of ˜2.000 mass%.
(3) A connector using the copper alloy sheet according to (1) or (2) .

The copper alloy sheet of the present invention has a high yield strength in the vertical direction of rolling and a good electrical conductivity. Therefore, this copper alloy plate material can be suitably used for connectors and terminal materials for lead frames, relays, switches, automobiles and the like for electric and electronic devices.
Moreover, according to the manufacturing method of the copper alloy plate material of this invention, the copper alloy plate material which has the said outstanding characteristic can be manufactured simply.

It is explanatory drawing which showed typically the X-ray diffraction rocking curve measuring apparatus. FIG. 1A shows the measurement in a state where φ = 0 (°) and the rolling surface is not inclined. FIG. 1B shows the measurement in a state where the rolling surface is inclined by φ = φ ₁ (°). It is a graph which shows the result of having measured the X-ray-diffraction rocking curve of {220} surface about the invention example 14. FIG. 16 is a graph showing the result of measuring an X-ray diffraction rocking curve of {220} plane for Comparative Example 24. It is a microscope picture which shows the TEM observation result of the invention example 25. 6 is a photomicrograph showing the TEM observation result of Comparative Example 23.

  A preferred embodiment of the copper alloy sheet material of the present invention will be described in detail. Here, the “copper alloy material” means a material obtained by processing a copper alloy material into a predetermined shape (for example, a plate, a strip, a foil, a bar, a wire, or the like). Among them, the plate material refers to a material having a specific thickness and being stable in shape and having a spread in the plane direction, and in a broad sense, includes a strip material and a tube material in which the plate is tubular.

  As a mechanism for increasing the strength of a metal material, solid solution strengthening, precipitation strengthening, dispersion strengthening, work hardening (dislocation strengthening), grain refinement (grain boundary strengthening), composite material strengthening and the like are known (for example, the following) See references). Note that Cu—Ni—Si, Cu—Ni—Co—Si, and Cu—Co—Si based copper alloys generally have precipitates (intermetallic compounds) such as NiSi, CoSi, and NiCoSi. It is a “precipitation strengthened copper alloy” that increases the mechanical strength by precipitation and dispersion.

(References)
"Material Engineering Series 3 Material Strength", Masaharu Kato et al., 1999, pages 69-86, Asakura Shoten Co., Ltd.

The present inventors have completed the present invention while studying a strengthening mechanism different from these conventional strengthening mechanisms. That is, it is a strengthening mechanism that brings a solute element into an intermediate state between solid solution and precipitation by strengthening by controlling the crystal orientation and strengthening by suppressing the second phase having a particle diameter of 20 nm or more. .
In the present invention, a copper alloy sheet material having high electrical conductivity and high yield strength in the vertical direction of rolling is obtained by superimposing dislocation strengthening by strong working on precipitation strengthening and grain refinement strengthening. It is.
Since the copper alloy sheet of the present invention has a high yield strength, it can be used as a spring material that is difficult to sag. For this reason, it is suitable as a connector material, for example.

(X-ray diffraction intensity ratio by X-ray diffraction rocking curve measurement)
Regarding the X-ray diffraction of {220} plane from the rolled surface of the copper alloy sheet, the relationship between the scan angle (φ (°), incident angle) and the diffraction intensity (I) by the apparatus schematically shown in FIG. Measurement (so-called rocking curve measurement). In this measurement, the rolled surface of the sample (copper alloy plate material) 1 is irradiated with X-rays from the radiation source 2 and the diffracted X-rays are detected by the detector 3. Since there are a plurality of types of crystal grains having different crystal planes in the sample of the copper alloy sheet, the detector 3 diffracts X-rays 5 that are diffracted by the crystal planes that satisfy the Bragg diffraction condition with respect to the incident X-rays 4. Can be detected. Since the parent phase in the copper alloy sheet of the present invention is a face-centered cubic lattice (fcc), the crystal plane on which X-rays are diffracted is the {200} plane, {220} plane, {111} plane, {311} plane Etc. Among them, the present invention focuses on the {220} plane where the diffraction intensity can be detected high, and the {220} plane is tilted by φ (°) with respect to the rolling plane with the rolling direction (RD) as the rotation axis. The diffraction intensity of a crystal grain having a crystal plane is measured. Thereby, the texture state of the copper alloy sheet is specified. That is, in the measurement of the present invention, the diffraction condition (X-ray incident angle θ (°)) when the {220} plane satisfies the Bragg diffraction condition is adopted. Note that RD, TD, and ND in FIG. 1 indicate a rolling direction, a rolling vertical direction (width direction), and a rolling surface vertical direction (thickness direction) of the sample 1, respectively.

In the rocking curve measurement, in the measurement at φ = 0 (°) shown in FIG. 1A, diffraction occurs only in the crystal grains in which {220} planes are arranged in parallel to the rolling surface. That the diffraction intensity of this diffracted X-ray is high means that many crystal grains having {220} planes parallel to the rolled surface are present on the rolled surface. Further, in the measurement at φ = φ ₁ (°) shown in FIG. 1B, the sample (copper alloy plate material) 1 is in a state inclined by φ ₁ (°) with the rolling direction (RD) as the rotation axis. The corresponding measurement is performed. Accordingly, diffraction occurs only in crystal grains in which the {220} plane is inclined by φ ₁ (°) with respect to the rolling plane with the rolling direction (RD) as the rotation axis. By measuring the diffraction intensity of this diffracted X-ray, information corresponding to the abundance of crystal grains whose {220} plane is inclined by φ ₁ (°) with respect to the rolling surface with the rolling direction as the rotation axis can be obtained. .

The inventors of the present invention increased the vertical direction of rolling of a copper alloy sheet as R = I ₀ / I ₃₀ , which is the ratio of the diffraction intensities I ₀ and I ₃₀ when φ = 0 (°) and φ = 30 (°). It has been found that the yield strength in the direction (TD) increases. The deformation of the metal material is borne by the slip deformation of the crystal, and the yield strength changes depending on the direction of the slip surface and the slip direction. In the crystal orientation in which the {220} plane faces the rolling surface (corresponding to φ = 0 (°)), crystal slip that affects the yield strength in the TD direction is relatively difficult to occur. Conversely, in a crystal arrangement in which the {220} plane is inclined 30 ° with respect to the rolling plane with the rolling direction as the rotation axis (corresponding to φ = 30 (°)), the crystal slip that affects the yield strength in the TD direction. Is relatively easy to happen. Therefore, a copper alloy sheet having an increased yield strength in the TD direction can be obtained by using a texture with an increased R = I ₀ / I ₃₀ .

  In the present invention, when R described above is 20 or more, the strength of the copper alloy sheet is high, and a predetermined good yield strength is obtained. More preferably, R is 25 or more, more preferably 30 or more. Although there is no restriction | limiting in particular in the upper limit of R, Usually, it is 100 or less. If the value of R is too low, it corresponds to a state of crystal orientation distribution in which slip deformation is easy, and good yield strength cannot be obtained.

  The difference between the value measured on the surface of the rolled surface of the copper alloy sheet material and the value measured on the inner half of the copper alloy sheet at half the sheet thickness after half-etching is 20% or less. It was confirmed that an equivalent metal structure was formed in the thickness direction. Therefore, in the present invention, for the sake of convenience, the R value measured from the rolling surface is specified.

(Dispersion density of the second phase)
In the present invention, the metal structure of the copper alloy sheet material contains particles of the second phase having a particle diameter of 20 nm or more at a density of 15 particles / μm ² or less. The second phase particles are observed with a transmission electron microscope (TEM). When the density of the second phase having a particle diameter of 20 nm or more is 15 particles / μm ² or less, a good high strength, that is, a predetermined good yield strength can be obtained. This low density corresponds to the fact that the second phase is dispersed in a size smaller than 20 nm or a size like an atomic group. In such a state, crystal slip is most difficult to occur. It is considered to be.

(Alloy composition)
・ Ni, Co, Si
It is an element constituting the second phase. These form the intermetallic compound. These are essential addition elements of the present invention.
The total content of any one or two of Ni and Co is 1.8 to 6.0% by mass, preferably 2.6 to 6.0% by mass, more preferably 3.4 to 6.0%. % By mass. Further, the content of Si is 0.4 to 1.6 mass%, preferably 0.55 to 1.6 mass%, more preferably 0.8 to 1.6 mass%. When the addition amount is too small, the effect obtained is insufficient, and when it is too large, material cracking may occur during the rolling process.

-Other elements The copper alloy sheet material of the present invention is at least one element selected from the group consisting of Sn, Zn, Ag, Mn, P, Mg, Cr, Zr, Fe and Ti in addition to the essential additive elements. May be contained as an optional additive element. These elements have been confirmed to increase the R value. When contained, the content of at least one element selected from the group consisting of Sn, Zn, Ag, Mn, P, Mg, Cr, Zr, Fe and Ti is 0.005 to 2.0% by mass in total. And However, if the content of these optional additive elements is too large, there may be a negative effect of lowering the conductivity.

-Inevitable impurities Inevitable impurities in the alloy composition are ordinary elements contained in copper alloys. Examples of inevitable impurities include O, H, S, Pb, As, Cd, and Sb. These are allowed to contain up to about 0.1% by mass as the total amount.

(Production method)
In a normal precipitation hardening type copper alloy material manufacturing method, after making it into a supersaturated solid solution state by solution heat treatment, it is precipitated by aging treatment, and temper rolling (finish rolling) and temper annealing (low temperature annealing, (Strain relief annealing) is performed.

In contrast, in the present invention, strengthening by controlling the crystal orientation represented by the diffraction intensity ratio I ₀ / I ₃₀ which is a predetermined R value in the X-ray diffraction rocking curve measurement of the {220} plane, and the particle diameter In order to achieve a state in which two strengthening mechanisms of strengthening by suppressing the second phase of 20 nm or more to a predetermined density or less coexist, a process different from the conventional method is effective. For example, the following process is effective, but the manufacturing method is not limited to the following method as long as the crystal orientation and the dispersion state of the second phase defined in the present invention are satisfied.

  An example of the production method of the present invention is melting and casting [Step 1] to obtain an ingot, and this ingot is subjected to homogenization heat treatment [Step 2], hot working such as hot rolling [Step 3], Water cooling [Step 4], optional intermediate cold rolling [Step 5], heat treatment for aging precipitation [Step 6], finish cold rolling [Step 7], temper annealing [Step 8] in this order The method of performing is mentioned.

The processing corresponding to the above-mentioned cold rolling [Step 7] in the conventional manufacturing method was only aimed at reducing the plate thickness, as called intermediate rolling or intermediate rolling. Therefore, in order to increase productivity, the main focus was on reducing the number of rolling passes, and it was preferable that the state before the intermediate or intermediate cold rolling had a low strength.
On the other hand, in the present invention, the finish cold rolling [Step 7] is important for controlling the crystal orientation and the dispersion state of the second phase, and is performed as a strong process at a high processing rate of 95% or more. Further, the second phase is precipitated and dispersed in advance in the heat treatment [Step 6] for aging precipitation before the cold rolling [Step 7]. In this case, the strength in the state before the finish cold rolling [Step 7] may be high, but if it is within the range of the alloy composition defined in the present invention, the production is not caused without causing cracks. Is possible.

The preferable heat treatment and processing conditions in each step are as follows.
The homogenization heat treatment [Step 2] is held at 900 to 1040 ° C. for 1 hour or longer, preferably 5 hours to 10 hours.
The hot working [step 3] such as hot rolling is performed at a temperature range of 500 to 1040 ° C. from the start to the end of hot working, and the working rate is about 10 to 90%.
The water cooling [Step 4] is also called quenching, and the cooling rate is usually 1 to 200 ° C./second.
In the intermediate cold rolling [step 5] optionally performed, the processing rate is 1 to 50%. Cold rolling [Step 5] may be omitted.
The heat treatment for aging precipitation [Step 6] is also called an aging treatment, and the condition is holding at 350 to 600 ° C. for 5 minutes to 10 hours, and a preferable temperature range is 360 to 410 ° C.
The finish cold rolling [Step 7] processing rate is 95% or more, preferably 97% or more.

Here, the processing rate (or rolling rate) is a value defined by the following equation.
Processing rate (%) = {(t ₁ −t ₂ ) / t ₁ } × 100
In the formula, t ₁ represents the thickness before rolling, and t ₂ represents the thickness after rolling.

  The temper annealing [Step 8] is also referred to as low temperature annealing or strain relief annealing, and is maintained at 200 to 500 ° C. for 5 seconds to 2 hours. If the holding time is too long, the yield strength may be low, and the preferable holding time is within 30 minutes.

(Physical properties)
In the one preferred embodiment of the copper alloy sheet of the present invention, the yield strength in the rolling direction perpendicular (also referred to as yield stress or 0.2% proof stress) is 1 020MPa or more, good Mashiku is 1080MPa or more, and more preferably 1140MPa or more is there. The conductivity is preferably 13% IACS or more, more preferably 15% IACS or more, still more preferably 17% IACS or more, and particularly preferably 19% IACS or more.
In the present invention, the yield strength is a value based on JIS Z2241. The “% IACS” represents the electrical conductivity when the resistivity 1.7241 × 10 ⁻⁸ Ωm of universal standard annealed copper (International Annealed Copper Standard) is 100% IACS.

  Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited thereto.

Example 1
An alloy raw material containing the alloy constituent elements shown in Table 1 and the balance consisting of Cu and inevitable impurities is melted in a high frequency melting furnace, and this is cast to obtain an ingot, which is at 900 to 1040 ° C. for 1 hour or longer The homogenization heat processing to hold | maintain was performed, it hot-rolled to plate | board thickness 12mm with this high temperature state, and water-cooled immediately. With this state as a providing material, in the following A, B, C, D, E production method, according to the invention example according to the present invention and a test material of a copper alloy sheet material of a comparative example separately from this, Manufactured. Table 1 shows which method of A to E was used. The final thickness of the copper alloy sheet was 150 μm unless otherwise specified.

(Manufacturing method A)
An aging treatment at 350 to 600 ° C. for 5 minutes to 10 hours, cold rolling with a processing rate of 95% or more, and temper annealing were performed in this order.

(Manufacturing method B)
Cold rolling with a processing rate of 1 to 50%, aging treatment at 350 to 600 ° C. for 5 minutes to 10 hours, cold rolling with a processing rate of 95% or more, and temper annealing were performed in this order.

(Manufacturing method C)
An aging treatment for holding at 350 to 600 ° C. for 5 minutes to 10 hours, cold rolling at a working rate of 85 to 94%, and temper annealing were performed in this order.

(Manufacturing method D)
Cold rolling with a processing rate of 95% or more, aging treatment at 350 to 600 ° C. for 5 minutes to 10 hours, cold rolling with a processing rate of 1 to 50%, and temper annealing were performed in this order.

(Manufacturing method E)
Cold rolling with a processing rate of 95% or more, solution treatment for quenching after holding at 800 to 1000 ° C. for 5 to 60 seconds, aging treatment for holding at 350 to 600 ° C. for 5 minutes to 10 hours, processing rate of 1 to 50% cold rolling and temper annealing were performed in this order.

The conditions for temper annealing in production methods A to E were maintained at 200 to 500 ° C. for 5 seconds to 2 hours.
After each heat treatment and rolling, the surface oxide layer was removed by chamfering, acid cleaning, or surface polishing, if necessary, depending on the state of oxidation and roughness of the material surface. Further, according to the shape, correction with a tension leveler was performed as necessary.

  Moreover, as a manufacturing method of another comparative example, it prototyped with the following manufacturing methods F, G, and H, and obtained the test material of the copper alloy board | plate material.

(Manufacturing method F) Invention example No. 2006-009108. 1 Production Method The raw materials giving the copper alloy composition shown in the following table were melted using an atmospheric melting furnace and cast into an ingot having a thickness of 20 mm and a width of 60 mm. The ingot was subjected to homogenization annealing at 1000 ° C. for 3 hours, and hot rolling was started at this temperature. When the thickness reached 15, 10 and 5 mm, the material in the middle of rolling was reheated at 1000 ° C. for 30 minutes, and the plate thickness was 3 mm after hot rolling. Then, chamfering, cold rolling to a plate thickness of 0.625 mm (working rate 79%), solution treatment held at 800 ° C. for 3 minutes, water cooling, cold rolling to a plate thickness of 0.5 mm (working rate 20%) ), And an aging treatment of holding at 400 to 600 ° C. for 3 hours was performed in this order.

(Manufacturing method G) Manufacturing method of JP-A-8-319527 A raw material giving the copper alloy composition shown in the following table is melted under a charcoal coating in the atmosphere using a high-frequency melting furnace, and the molten metal is used as a carbon mold. Casting was performed to obtain an ingot having a thickness of 50 mm, a width of 80 mm, and a length of 180 mm. Thereafter, the surface of the ingot was scraped off, heated to 950 ° C., hot-rolled to a thickness of 15 mm, and immersed in water at a temperature of 750 ° C. or higher for rapid cooling. Next, chamfering, cold rolling (to a plate thickness of 0.20 mm) (working rate of about 98%), soaking treatment in a salt bath adjusted to 750 ° C. for 30 seconds and then water quenching, soaking in water Then, rapid cooling, cold rolling (to a sheet thickness of 0.15 mm) (processing rate 25%), and precipitation treatment of heating at a temperature of 500 ° C. for 2 hours were performed in this order.
The production method G corresponds to the production method of the example described in Patent Document 3 (Japanese Patent Laid-Open No. 2006-152392).

(Manufacturing method H) No. 2008-013836. 4. Manufacturing method 4 The raw material which gives the copper alloy composition shown in the following table is melted and cast using a vertical continuous casting machine, and the resulting slab is heated to 950 ° C. in a temperature range of 950 to 650 ° C. A hot rolling was performed to obtain a plate material having a thickness of 10 mm, followed by rapid cooling (water cooling). Next, chamfering, cold rolling at a rolling rate of 91%, solution treatment (700 to 800 ° C., 10 seconds to 10 minutes) with an average crystal grain size exceeding 25 μm to 40 μm, hardness peaks at 450 ° C. An aging treatment for holding for as long as possible, finish cold rolling (up to a sheet thickness of 0.2 mm) at a rolling rate of 35%, and low temperature annealing for 5 minutes at 400 ° C. were performed in this order.

  About the test material of the invention example according to this invention and a comparative example, each characteristic was measured and evaluated as follows. The results are shown in Table 1.

a. Ratio of diffraction intensity measured by X-ray diffraction rocking curve on {220} plane [R]
Using the apparatus shown in FIG. 1 (a) and FIG. 1 (b), measurement was performed using each test material of a copper alloy sheet as a target. The tube voltage and tube current were 40 kV and 30 mA, respectively. The 2θ value at which the diffraction intensity of the {220} plane is maximized is measured by θ / 2θ measurement (2θ = 74.2 (°) satisfies the Bragg diffraction condition), and the detector is fixed to that condition. did. Then, the condition is φ = 0 (°) (FIG. 1A), and the φ axis of the copper alloy plate material sample until φ = 30 (°) (φ ₁ = 30 (°) in FIG. 1B). The X-ray diffraction rocking curve was measured by changing the rolling direction RD in 1 ° steps with the rotation axis as the rotation axis. The curve was smoothed by methods such as moving average to remove noise. Then, phi = 0 the ratio of a diffraction intensity when a diffraction intensity when a (°) _{(I 0)} and _{φ = 30 (°) (I} 30), was obtained _R = _I 0 _/ I _30.

As representative examples, X-ray diffraction rocking curves measured for Invention Example 14 and Comparative Example 24 are shown in FIGS. 2 and 3, respectively. The vertical axis in FIGS. 2 and 3 represents a value (I _φ / I ₃₀ ) obtained by normalizing the diffraction intensity I _φ at each φ (°) by I ₃₀ . Although not shown, when φ = 0 (°) to φ = −30 (°) are measured, the rocking curves obtained in FIGS. 2 and 3 are symmetrical on the vertical axis due to crystal symmetry. Curve is obtained. The number of measurements (n number) was 3 times, and the average value of 3 times of R was obtained.
Here, in the FIGS. 2 and 3 normalized by I _30, Y-axis (vertical axis) intercept means a value of R. It can be seen from FIG. 2 that R = I ₀ / I ₃₀ is about 26 and from FIG. 3, R = I ₀ / I ₃₀ is about 10.

b. Second phase density [ρ]
Each specimen was observed by a thin film method using a transmission electron microscope (TEM). The acceleration voltage was 300 kV. The observation magnification is 100,000 times, and the area of one visual field is about 4 μm ² . This was observed with 20 fields of view, the number of second phases having a size of 20 nm or more was measured, and divided by the total area to obtain the number per unit area (density, pieces / μm ² ).
As representative examples, TEM photographs observed for Invention Example 25 and Comparative Example 23 are shown in FIGS. 4 and 5, respectively. The portion of the comparative example 23 shown in FIG. 5 and having a substantially round shape with a clear outline is the second phase particle.
From the comparison of these TEM photographs, it can be seen that in Comparative Example 23 of FIG. 5, the second phase having a size of 20 nm or more is dispersed more than 15 / μm ² . On the other hand, in the invention example 25 of FIG. 4, the second phase having a particle size of 20 nm or more is hardly observed, and the number is less than 15 particles / μm ² .

c. Yield strength in the vertical direction of rolling [YS]
Three test pieces of JIS Z2201-13B cut out from each test material with the vertical direction of rolling (TD) as the longitudinal direction were measured according to JIS Z2241, and the average value was shown. A stress-strain curve was collected to obtain a 0.2% yield strength (yield strength).

d. Conductivity [EC]
For each specimen, the specific resistance was measured by a four-terminal method in a constant temperature bath maintained at 20 ° C. (± 0.5 ° C.) to calculate the conductivity. In addition, the distance between terminals was 100 mm.

As shown in Table 1, Invention Examples 11 to 16 that satisfy the provisions of the present invention have excellent characteristics. The higher the concentration of Ni, Co, and Si within a predetermined range, the higher YS was shown.
On the other hand, in Comparative Example 11, YS was inferior because Ni, Co, and Si were too little. Moreover, in Comparative Example 12 in which there were too many Ni, Co, and Si, rolling cracks occurred and the productivity was inferior. In Comparative Example 13 by Production Method C, R was too low, in Comparative Example 14 by Production Method D, ρ was too high, and in Comparative Example 15 by Production Method E, R and ρ were not satisfied, and YS was inferior. As other comparative examples, Comparative Examples 16, 17, and 18 by the production methods F, G, and H did not satisfy R and ρ, and YS was inferior.

(Example 2)
By the same manufacturing method and test / measurement method as in Example 1, copper alloy sheet materials were manufactured using various copper alloys shown in Table 2, and their characteristics were evaluated. The results are shown in Table 2.

As shown in Table 2, Invention Examples 21 to 27 that satisfy the provisions of the present invention have excellent characteristics. It can be seen that R is increased by the effect of the auxiliary additive element and YS is improved.
On the other hand, in Comparative Example 21, the EC was inferior because there were too many auxiliary additive elements. In Comparative Example 22 by Production Method C, R was too low, in Comparative Example 23 by Production Method D, ρ was too high, and in Comparative Example 24 by Production Method E did not satisfy R and ρ, and YS was inferior. As other comparative examples, Comparative Examples 25, 26, and 27 using the production methods F, G, and H did not satisfy R and ρ, and YS was inferior.

1 Sample (copper alloy sheet)
2 radiation source 3 detector 4 incident X-ray 5 diffracted X-ray

Claims (3)

One or two of Ni and Co in total 1.8 to 6.0 mass%, Si 0.4 to 1.6 mass%, Sn 0 to 1.95 mass%, Zn 0 to 1.92 mass%, Mn from 0 to 0.15 mass%, P from 0 to 0.05 mass%, Mg from 0 to 0.15 mass%, Cr from 0 to 0.15 mass%, Zr 0 to 0.06% by mass, and at least one element selected from the group consisting of 0 to 0.23% by mass of Fe is contained in a total of 0 to 2.0% by mass, and the balance is made of copper and inevitable impurities. A copper alloy sheet having an alloy composition,
In the metal structure of the copper alloy plate material, the second phase having a particle diameter of 20 nm or more is included at a density of 15 pieces / μm ² or less,
In the X-ray diffraction measurement of the {220} plane of the parent phase of the copper alloy plate having an inclination of φ (°) from the rolling surface with the rolling direction of the copper alloy plate as the rotation axis, φ = 0 (°) and φ = 30 (°) der _R = I 0 _{/ I 30} 20 or more which is the ratio of the diffraction intensity _{I 0} and _{I 30} when the is,
Copper alloy sheet yield strength in the rolling vertical direction of the copper alloy sheet is characterized in der Rukoto than 1020 mPa.   Sn is 0 to 1.95 mass%, Zn is 0 to 1.92 mass%, Mn is 0 to 0.15 mass%, P is 0 to 0.05 mass%, Mg is 0 to 0.15 mass%, A total of at least one element selected from the group consisting of 0 to 0.15 mass% Cr, 0 to 0.06 mass% Zr, and 0 to 0.23 mass% Fe is 0.005 to 2. The copper alloy sheet according to claim 1, containing 000 mass%. A connector using the copper alloy sheet according to claim 1 .