JPWO2011068126A1 - Copper alloy sheet and manufacturing method thereof - Google Patents

Abstract

[PROBLEMS] To provide a copper alloy having excellent bending workability and excellent strength and suitable for a lead frame, a connector, a terminal material, etc. for an electric / electronic device, and a connector, a terminal material, a relay, a switch, etc. for an automobile. A plate material and a manufacturing method thereof are provided. In the crystal orientation analysis in EBSD (Electron Back Scatter Diffraction) measurement, regarding the accumulation of atomic planes in the width direction (TD) of a rolled plate, the normal of the (111) plane and the TD form. The copper alloy sheet | seat material whose area ratio of the area | region which has an atomic surface whose angle of angle is less than 20 degrees is 50% or less, yield strength is 500 Mpa or more, and electrical conductivity is 30% IACS or more, and its manufacturing method. [Selection figure] None

Description

  The present invention relates to a copper alloy sheet and a method for manufacturing the same, and more particularly to a copper alloy sheet that is applied to lead frames, connectors, terminal materials, relays, switches, sockets, and the like for in-vehicle components and electrical / electronic devices, and a method for manufacturing the same. .

Characteristic items required for copper alloy sheet materials used in applications such as lead frames, connectors, terminal materials, relays, switches and sockets for automotive parts and electrical / electronic equipment include, for example, conductivity, yield strength (yield) Stress), tensile strength, bending workability, and stress relaxation resistance. In recent years, the level of these required characteristics has increased as electric and electronic devices have become smaller, lighter, more functional, denser, and used in higher temperatures.
Therefore, the following changes are mentioned in the situation where a copper alloy plate material is used.
First, as the functionality of automobiles, electrical equipment, and electronic devices has increased, the number of connectors has been increasing, and so miniaturization of terminals and contact parts has been progressing. For example, a movement to downsize a terminal having a tab width of about 1.0 mm to 0.64 mm is progressing.
Secondly, the base material is becoming thinner due to the reduction of mineral resources and weight reduction of parts, and in order to maintain the spring contact pressure, a base material with higher strength than before is used. ing.
Third, the use environment is becoming hot. For example, automobile parts are being reduced in weight to reduce carbon dioxide generation. For this reason, an electronic device such as an ECU for controlling an engine, which has been conventionally installed on a door, is installed in an engine room or in the vicinity of the engine, and a movement for shortening a wire harness between the electronic device and the engine is progressing. .

With the above changes, the following problems have arisen in the copper alloy material.
First, with the miniaturization of the terminals, the bending radius of the bending process applied to the contact part and the spring part becomes smaller, and the material is subjected to a stricter bending process than before. Therefore, there is a problem that cracks and wrinkles occur in the material.
Second, with the increase in strength of materials, there is a problem that cracks occur in the materials. This is because the bending workability of the material is generally in a trade-off relationship with the strength.
Third, when a crack occurs in the bent part applied to the contact part or spring part, the contact pressure of the contact part decreases, the contact resistance of the contact part increases, the electrical connection is insulated, and the connector As the function is lost, it becomes a serious problem.

Several proposals have been made to solve this demand for improvement in bending workability by controlling the crystal orientation. In Patent Document 1, in a Cu—Ni—Si based copper alloy, the crystal grain size and the X-ray diffraction intensity from the {311}, {220}, {200} planes satisfy a certain condition. It has been found that bending workability is excellent. Further, in Patent Document 2, in a Cu—Ni—Si based copper alloy, bending workability is excellent when the crystal orientation satisfies the condition that the X-ray diffraction intensity from the {200} plane and the {220} plane is satisfied. Has been found. Further, in Patent Document 3, it has been found that in a Cu—Ni—Si based copper alloy, bending workability is excellent by controlling the ratio of the Cube orientation {100} <001>. In addition, Patent Documents 4 to 8 propose materials having excellent bending workability defined by X-ray diffraction intensities for various atomic planes. In Patent Document 4, in the Cu—Ni—Co—Si based copper alloy, the X-ray diffraction intensity from the {200} plane is from the {111} plane, {200} plane, {220} plane, and {311} plane. It has been found that bending workability is excellent when the crystal orientation satisfies a certain condition with respect to the X-ray diffraction intensity. Patent Document 5 shows that in a Cu—Ni—Si-based copper alloy, bending workability is excellent when the crystal orientation satisfies the condition that the X-ray diffraction intensity from the {420} plane and the {220} plane is satisfied. Has been issued. In Patent Document 6, it has been found that, in a Cu—Ni—Si based copper alloy, bending workability is excellent when the crystal orientation satisfies a certain condition with respect to the {123} <412> orientation. In Patent Document 7, in a Cu—Ni—Si based copper alloy, in the case of crystal orientation satisfying the condition that the X-ray diffraction intensity from the {111} plane, {311} plane, and {220} plane is satisfied, It has been found that the bending workability (described later) is excellent. Further, in Patent Document 8, in a Cu—Ni—Si based copper alloy, bending is performed when the crystal orientation satisfies the condition that the X-ray diffraction intensity from the {200} plane, {311} plane, and {220} plane is satisfied. It has been found that processability is excellent.
The specifications based on the X-ray diffraction intensity in Patent Documents 1, 2, 4, 5, 7, and 8 specify the accumulation of specific crystal planes in the plate surface direction (rolling normal direction, ND).

JP 2006-009137 A JP 2008-013836 A JP 2006-283059 A JP 2009-007666 A JP 2008-223136 A JP 2007-092135 A JP 2006-016629 A JP-A-11-335756

  By the way, the invention described in Patent Document 1 or Patent Document 2 is based on the measurement of crystal orientation by X-ray diffraction from a specific crystal plane, and is very small in the distribution of crystal orientation having a certain spread. It only concerns some specific aspects. Moreover, only the crystal plane in the plate direction (ND) is measured, and it cannot be controlled which crystal plane is oriented in the rolling direction (RD) or the plate width direction (TD). Therefore, the method is still insufficient to completely control the bending workability. In the invention described in Patent Document 3, the effectiveness of the Cube orientation is pointed out, but other crystal orientation components are not controlled, and there are cases where the improvement of bending workability is insufficient. It was. Further, in Patent Documents 4 to 8, only the measurement and control of the specific crystal plane or orientation have been studied, and the bending workability may not be improved as in Patent Documents 1 to 3. It was.

  In view of the problems as described above, the object of the present invention is to provide excellent bending workability, excellent strength, and lead frames, connectors, terminal materials, etc. for electrical and electronic equipment, such as connectors for automobiles and terminals. An object of the present invention is to provide a copper alloy sheet suitable for materials, relays, switches, and the like, and a method for manufacturing the same.

  The present inventors have made various studies and studied copper alloys suitable for electric / electronic component applications, and reduced the region in which the (111) plane faces in the width direction (TD) of the rolled plate, thereby bending the work. It was found that cracking at the time was suppressed, and further, bending workability could be remarkably improved by setting the area ratio of the region to a predetermined value or less. In addition, it has been found that by using a specific additive element in this alloy system, the strength and stress relaxation resistance can be improved without impairing electrical conductivity and bending workability. The present invention has been made based on these findings.

That is, the present invention provides the following solutions.
(1) In the crystal orientation analysis in EBSD (Electron Back Scatter Diffraction) measurement, regarding the accumulation of atomic planes in the width direction (TD) of the rolled plate, the angle formed by the normal of the (111) plane and TD An area ratio of a region having an atomic plane with an angle of 20 ° or less is 50% or less, a proof stress is 500 MPa or more, and a conductivity is 30% IACS or more.
(2) The alloy composition contains any one or two of Ni and Co in a total amount of 0.5 to 5.0 mass%, Si of 0.1 to 1.5 mass%, and the balance is made of copper and inevitable impurities. The copper alloy sheet material according to (1), wherein
(3) Furthermore, 0.005 to 2.0 mass% in total is contained at least one selected from the group consisting of Sn, Zn, Ag, Mn, B, P, Mg, Cr, Fe, Ti, Zr and Hf. The copper alloy sheet material according to (1) or (2), wherein
(4) The copper alloy sheet according to any one of (1) to (3), which is a connector material.
(5) A method for producing a copper alloy sheet material according to any one of (1) to (4), wherein the copper alloy sheet material that gives the copper alloy sheet material is cast [Step 1] and homogenized. Heat treatment [Step 2], Hot working [Step 3], Cold rolling [Step 6], Heat treatment [Step 7], Cold rolling [Step 8], Intermediate recrystallization heat treatment [Step 9], Final solution heat treatment [ Step 10] is performed in this order, followed by aging precipitation heat treatment [Step 11], and the intermediate recrystallization heat treatment [Step 9] is performed when (P− 200 ° C. to (P-10) ° C. for 1 second to 20 hours, and the final solution heat treatment [Step 10] is (P + 10) ° C. to (P + 150) ° C. for 1 second to 10 seconds. A method for producing a copper alloy sheet material, characterized by holding for a minute.
(6) After the aging precipitation heat treatment [Step 11], cold rolling [Step 12] and temper annealing [Step 13] are performed in this order in the copper alloy sheet according to (5), Production method.

The copper alloy sheet material of the present invention is excellent in bending workability and has excellent strength, such as lead frames, connectors and terminal materials for electric and electronic equipment, connectors and terminal materials for automobiles, relays, switches, etc. It is suitable for.
In addition, the copper alloy sheet manufacturing method of the present invention is excellent in the above bending workability and has excellent strength, such as lead frames, connectors and terminal materials for electric and electronic equipment, connectors for automobiles, etc. This is a suitable method for producing a copper alloy sheet suitable for terminal materials, relays, switches, and the like.

It is explanatory drawing of the test method of a stress relaxation resistance, (a) shows the state before heat processing, (b) shows the state after heat processing, respectively. It is a graph which shows the typical example of the electrical conductivity change accompanying the heat processing temperature rise, and shows the method of determining temperature (P) degreeC by which a solute atom completely dissolves by it. (A) illustrates an example of an atomic plane in which the angle between the normal of the (111) plane and the TD is within 20 °, and (b) illustrates the normal of the (111) plane and the TD. An example of an atomic plane having an angle of more than 20 ° is illustrated. 3 (a) and 3 (b), a conical region indicated by a dotted line indicates a region where an angle formed with the normal line of the (111) plane is within 20 °. Among typical texture orientation components in FCC (face-centered cubic lattice) metal, an atomic plane whose angle between the normal of the (111) plane and TD is within 20 ° is in the width direction of the rolled sheet (TD). An example of a texture orientation component that faces is illustrated.

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 stable in shape and having a spread in the surface direction, and in a broad sense, includes a strip material. Here, in the plate material, “material surface layer” means “plate surface layer”, and “material depth position” means “position in the plate thickness direction”. The thickness of the plate material is not particularly limited, but it is preferably 8 to 800 μm, and more preferably 50 to 70 μm, considering that the effects of the present invention are better manifested and suitable for practical applications.
In addition, although the copper alloy plate material of this invention prescribes | regulates the characteristic with the integration rate of the atomic surface in the predetermined direction of a rolled sheet, this should just have such a characteristic as a copper alloy plate material. Therefore, the shape of the copper alloy sheet is not limited to a sheet or a strip, and in the present invention, the pipe can be interpreted and handled as a sheet.

(Regulation by EBSD measurement)
In order to clarify the cause of the occurrence of cracks during bending of a copper alloy sheet, the present inventors investigated in detail the metal structure of the material after bending deformation. As a result, it was observed that the base material was not uniformly deformed, but the deformation was concentrated only in the region of a specific crystal orientation, and the non-uniform deformation progressed. Due to the non-uniform deformation, wrinkles with a depth of several microns and fine cracks are generated on the surface of the base material after bending, but no solution has been found. However, as a result of intensive research, the inventors of the present invention have an atomic plane region in which the (111) plane is oriented in the width direction (TD) of the rolled sheet defined by EBDS measurement (this region will be described in detail below). It has been found that, when the amount is reduced, uneven deformation is suppressed, wrinkles generated on the surface of the base material are reduced, and cracks are suppressed.
As the mechanism of this phenomenon, the (111) plane is one of the orientations that are most easily work-hardened with respect to tensile stress, and it is considered that the dislocations are likely to proliferate even under stress during bending deformation. High density dislocations become a source of microvoids and cause cracks. It is considered that the bending workability is improved particularly in the BW bending in which the bending axis is parallel to the rolling direction by reducing the proportion of the atomic plane region in which the (111) plane faces TD.

FIG. 4 shows representative ones of the orientation components of the texture in which the atomic plane whose angle between the normal of the (111) plane and the TD is within 20 ° faces the TD. P orientation {0 1 1} <1 1 1>, SB orientation {1 8 6} <2 1 1>, S orientation {1 3 2} <6 4 3>, Z orientation {1 1 1} <1 1 0 >, Cube orientation twin orientation {1 2 2} <2 2 1>, Brass orientation {1 1 0} <1 1 2>, and the like. A state in which the proportion of the texture orientation component in which the (111) plane faces TD including these orientation components is comprehensively suppressed is the texture having a predetermined area ratio defined in the present invention. Conventionally, there is no known device that simultaneously controls the area ratio of atomic planes having these orientations.
When the area ratio of the region having an atomic plane in which the angle formed by the normal of the (111) plane and the TD is within 20 ° in the width direction (TD) of the rolled sheet is 50% or less, the above effect is obtained. can get. It is preferably 45% or less, more preferably 1% or more and 40% or less, and particularly preferably 30% or more and 35% or less. By defining this area ratio and specifying it in the above range, it is possible to improve the bending workability as described above.

In this specification, the crystal orientation display method takes a rectangular coordinate system in which the rolling direction (RD) of the material is the X axis, the sheet width direction (TD) is the Y axis, and the rolling normal direction (ND) is the Z axis. The ratio of the area where the (111) plane faces is defined by the area ratio. Calculate the angle between the two vectors of (111) plane normal and TD of each crystal grain in the measurement region, and sum the area for those having an atomic plane within 20 °. The value obtained by dividing by the total measurement area was defined as the area ratio (%) of the region having an atomic plane in which the angle formed by the normal of the (111) plane and the TD is within 20 °.
That is, in the present invention, regarding the accumulation of atomic planes in the width direction (TD) of the rolled sheet, the region having an atomic plane whose angle formed by the normal of the (111) plane and the TD is within 20 ° is: The (111) plane itself, which is normal to the width direction (TD) of the rolled sheet, which is the ideal orientation, with respect to the accumulation of atomic planes facing the width direction (TD) of the rolled sheet, that is, facing the TD, and the (111) plane The sum of the area of the plane orientation in which the atomic plane combining the respective atomic planes whose angle between the normal line and TD is within 20 ° exists. Hereinafter, these regions are also simply referred to as atomic plane regions in which the (111) plane faces TD.
FIG. 3 illustrates the above contents. FIG. 3A illustrates an example of an atomic plane in which the angle formed by the normal of the (111) plane and the TD is within 20 °. In this specification, the atomic plane shown in this example is shown. Is used in combination with a simplified description of an atomic plane having an orientation in which the (111) plane is oriented in the rolled sheet width direction (TD), so that an atomic plane having an orientation in which the (111) plane is oriented in the rolled sheet width direction (TD) Even if it is described, the sum of the plane orientations of atomic planes where the angle between the normal of the (111) plane and the TD is within 20 ° is assumed.
FIG. 3B illustrates an example of an atomic plane in which the angle formed by the normal of the (111) plane and the TD exceeds 20 °. An atomic plane having an orientation in which the (111) plane does not face in the direction (TD). In the copper alloy, there are eight (111) planes, but only the (111) plane whose normal vector is closest to TD is a vector in which the angle formed by the (111) plane normal is within 20 °. This area is indicated by a cone (dotted line) in the figure.
The information obtained in the azimuth analysis by EBSD includes azimuth information up to a depth of several tens of nanometers at which the electron beam penetrates into the sample. It was described as an area ratio.

The EBSD method was used for the analysis of the crystal orientation in the present invention. EBSD is an abbreviation for Electron Back Scatter Diffraction (Electron Back Scattering Diffraction). Reflected Electron Kikuchi Line Diffraction (Kikuchi Pattern) generated when a sample is irradiated with an electron beam in a Scanning Electron Microscope (SEM). This is the crystal orientation analysis technology used. In the present invention, a 500 μm square sample area containing 200 or more crystal grains was scanned in 0.5 μm steps, and the orientation was analyzed.
By using EBSD measurement for analysis of crystal orientation, it differs greatly from the measurement of the accumulation of specific atomic planes in the plate direction (ND) by the conventional X-ray diffraction method. Since it can be obtained with higher resolution, it is possible to acquire completely new knowledge about the crystal orientation that governs the bending workability.

  In the EBSD measurement, in order to obtain a clear Kikuchi diffraction image, it is preferable to perform the measurement after mirror polishing the surface of the substrate using colloidal silica abrasive grains after mechanical polishing. The measurement was performed from the plate surface.

(Alloy composition, etc.)
・ Ni, Co, Si
Copper or copper alloy is used as the connector material of the present invention. In addition to copper, copper alloys such as phosphor bronze, brass, white, beryllium copper, corson alloy (Cu-Ni-Si), etc. as those having electrical conductivity, mechanical strength and heat resistance required for connectors Is preferred. In particular, when it is desired to obtain an area ratio satisfying the specific crystal orientation accumulation relationship of the present invention, a pure copper-based material, a beryllium copper, and a precipitation type alloy including a Corson alloy are preferable. Furthermore, in order to achieve both high strength and high conductivity as required for the most advanced small terminal materials, Cu-Ni-Si, Cu-Ni-Co-Si, and Cu-Co-Si Precipitation copper alloys are preferred.
This is because, in a solid solution type alloy such as phosphor bronze or brass, a minute region having a Cube orientation in the cold-rolled material, which becomes a nucleus of Cube orientation grain growth in crystal grain growth during heat treatment, is reduced. This is because in a system with low stacking fault energy such as phosphor bronze and brass, a shear band is likely to develop during cold rolling.

  In the present invention, nickel (Ni), cobalt (Co), and silicon (Si), which are the first additive element group to be added to copper (Cu), are controlled by controlling the addition amount of Ni—Si, Co. It is possible to improve the strength of the copper alloy by precipitating a compound of -Si and Ni-Co-Si. The amount of addition is one or two of Ni and Co in total, preferably 0.5 to 5.0 mass%, more preferably 0.6 to 4.5 mass%, more preferably 0.8 to 4.0 mass%. The addition amount of Ni is preferably 1.5 to 4.2 mass%, more preferably 1.8 to 3.9 mass%, while the addition amount of Co is preferably 0.3 to 1.8 mass%, more preferably Is 0.5 to 1.5 mass%. In particular, when it is desired to increase the conductivity, it is preferable to make Co essential. By not adding too much the total amount of these elements, the electrical conductivity can be sufficiently secured, and by not making it too small, the strength can be sufficiently secured. The Si content is preferably 0.1 to 1.5 mass%, more preferably 0.2 to 1.2 mass%.

-Other elements Next, effects of additive elements that improve characteristics (secondary characteristics) such as stress relaxation resistance will be described. Preferred additive elements include Sn, Zn, Ag, Mn, B, P, Mg, Cr, Fe, Ti, Zr and Hf. In order to fully utilize the additive effect and not lower the electrical conductivity, the total amount is preferably 0.005 to 2.0 mass%, more preferably 0.01 to 1.5 mass%, more preferably It is 0.03-0.8 mass%. The conductivity can be sufficiently ensured by not adding the total amount of these additive elements. In addition, the effect which added these elements can fully be exhibited by not making these addition elements excessive with the total amount.

  The effect of adding each element is shown below. When Mg, Sn, and Zn are added to Cu—Ni—Si, Cu—Ni—Co—Si, and Cu—Co—Si copper alloys, the stress relaxation resistance is improved. The stress relaxation resistance is further improved by a synergistic effect when each of them is added together than when they are added alone. In addition, there is an effect of remarkably improving solder embrittlement.

  When Mn, Ag, B, and P are added, the hot workability is improved and the strength is improved.

  Cr, Fe, Ti, Zr, and Hf are finely precipitated as a single additive or a compound with Ni, Co, or Si as main additive elements, and contribute to precipitation hardening. Moreover, it precipitates with the magnitude | size of 50-500 nm as a compound, and there exists an effect which makes a crystal grain size fine by suppressing grain growth, and makes bending workability favorable.

(Manufacturing method etc.)
Next, a method for producing a copper alloy sheet according to the present invention (a method for controlling the crystal orientation) will be described. Here, a plate material (strip material) of a precipitation-type copper alloy will be described as an example, but the present invention can be applied to a solid solution alloy material, a dilute alloy material, and a pure copper material.
In general, a precipitation-type copper alloy is obtained by thinning a homogenized heat-treated ingot at each step of hot and cold, and performing a final solution heat treatment in a temperature range of 700 to 1020 ° C. to re-solidify solute atoms. Later, it is manufactured to satisfy the required strength by aging precipitation heat treatment and finish cold rolling. The conditions for the aging precipitation heat treatment and the finish cold rolling are adjusted according to characteristics such as desired strength and conductivity. The texture of the copper alloy is roughly determined by recrystallization that occurs during the final solution heat treatment in this series of steps, and finally determined by the rotation of the orientation that occurs during finish rolling.

  As a method for producing a copper alloy sheet according to the present invention, for example, a copper alloy material having a predetermined alloy component composition is melted by a high-frequency melting furnace, and this is cast to obtain an ingot [Step 1]. Is subjected to a homogenization heat treatment at 700 ° C. to 1020 ° C. for 10 minutes to 10 hours [Step 2], hot rolling with a processing temperature of 500 to 1020 ° C. and a processing rate of 30 to 98% [Step 3], and water cooling [Step 4], chamfering [Step 5], cold rolling at 50 to 99% [Step 6], heat treatment held at 600 to 900 ° C. for 10 seconds to 5 minutes [Step 7], cooling at a processing rate of 5 to 55% Intermediate processing [Step 8], (P-200) Intermediate recrystallization heat treatment held for 1 second to 20 hours at (P−200) ° C. or more and (P−10) ° C. or less [Step 9], (P + 10) at 1 ° C. or more and (P + 150) or less Perform final solution heat treatment [step 10] held for 10 seconds, then Aging precipitation heat treatment at 350 to 600 ° C. for 5 minutes to 20 hours [Step 11], finish rolling at a processing rate of 2 to 45% [Step 12], temper annealing to be maintained at 300 to 700 ° C. for 10 seconds to 2 hours [ By carrying out [Step 13], a method of obtaining the copper alloy sheet of the present invention by carrying out [Step 1] to [Step 13] in this order can be mentioned.

The copper alloy sheet material of the present invention is preferably manufactured by the manufacturing method of the above embodiment. However, if the predetermined area ratio is satisfied in the crystal orientation analysis in the EBSD measurement, the above [Step 1] to [Step 13]. ] Is not necessarily constrained to do all in this order. Although included in the above method, among [Step 1] to [Step 13], for example, [Step 11] may be ended as a final step. Alternatively, the above-mentioned [Step 11] to [Step 13] can be performed by repeating one or more of them two or more times. For example, before performing [Step 11], cold rolling [Step 12 ′] with a processing rate of 2 to 45% may be performed.
When the end temperature of the hot rolling [Step 3] is low, the precipitation rate becomes slow, so the water cooling [Step 4] is not necessarily required. The temperature at which the hot rolling is to be completed and water cooling is not required depends on the alloy concentration and the amount of precipitation during hot rolling, and may be appropriately selected. The chamfering [step 5] may be omitted depending on the scale of the material surface after hot rolling. Further, the scale may be removed by dissolution by acid cleaning or the like.
Hot rolling is a hot rolling performed at a temperature higher than the dynamic recrystallization temperature, and hot rolling is a hot rolling at a temperature higher than the room temperature and lower than the dynamic recrystallization temperature. Is generally. Also in the present invention, both are collectively called hot rolling.

In the method for producing a copper alloy sheet according to the present invention, the following production method is effective in reducing the ratio of the (111) plane facing in the sheet width direction in the final solution heat treatment.
As a general method for producing a conventional precipitation-type copper alloy, recrystallization also occurs during solution heat treatment, so that the two purposes of solid solution of solute atoms and recrystallization have been achieved. On the other hand, in the method for producing a copper alloy sheet according to the present invention, these two objectives are achieved one by one, and the crystal orientation of the texture is controlled at the same time. It is. That is, first, an intermediate recrystallization heat treatment [Step 9] is performed on the provided material, followed by a final solution heat treatment [Step 10].
The temperature of the intermediate recrystallization heat treatment and the final solution heat treatment is defined as a specific temperature range defined using P ° C., which is the temperature at which the solute atoms are completely dissolved.
The temperature of the intermediate recrystallization heat treatment is (P-200) ° C. or higher and (P-10) ° C. or lower. When this temperature is too low, recrystallization is insufficient, and when it is too high, the proportion of the (111) plane facing TD is not sufficiently reduced. The temperature of the intermediate recrystallization heat treatment is preferably (P-170) ° C to (P-20) ° C, more preferably (P-140) ° C to (P-30) ° C.
The temperature of the final solution heat treatment is (P + 10) ° C. or higher and (P + 150) ° C. or lower. When this temperature is too low, the solute atoms are not sufficiently dissolved, and when the temperature is too high, the crystal grains become coarse. The temperature of the final solution heat treatment is preferably (P + 20) ° C. to (P + 130) ° C., more preferably (P + 30) ° C. to (P + 100) ° C.

  The temperature P (° C.) at which the solute atoms are completely dissolved is determined by the following general method. The ingot is homogenized at 1000 ° C. for 1 hour, then subjected to hot rolling and cold rolling to form a plate material, and then subjected to water quenching after heat treatment of holding at 700 ° C. every 10 ° C. for 30 seconds in a salt bath. The state of solid solution and precipitation at each temperature was frozen and the conductivity was measured. The conductivity was used as a substitute characteristic for the amount of solid solution element, and the temperature at which the decrease in conductivity with the increase in the heat treatment temperature was saturated was defined as the complete solid solution temperature P (° C.). A typical conductivity change and a method for determining the temperature P (° C.) thereby are schematically shown in FIG. The complete solution temperature P (° C.) for a specific composition varies depending on the type of alloy, processing / processing conditions, and the like, but is typically about 720 to 980 ° C. as a typical example.

The treatment time for the intermediate recrystallization heat treatment is 1 second to 20 hours, more preferably 5 seconds to 10 hours. When the treatment time of the intermediate recrystallization heat treatment is too short, recrystallization does not proceed, and when it is too long, crystal grains become coarse and formability deteriorates.
The treatment time for the final solution heat treatment is 1 second to 10 minutes, more preferably 5 seconds to 5 minutes. When the treatment time of the final solution heat treatment is too short, the solute atoms are not sufficiently dissolved, and when it is too long, the crystal grains are coarsened and the formability is lowered.

  In the present invention, the intermediate heat treatment (step 7) also has a special technical meaning and will be described here. A structure in which the entire surface is not recrystallized can be obtained by heat treatment at a temperature slightly lower than the complete solid solution temperature P ° C. and at a relatively low temperature. That is, among the crystal orientations in the rolled material, there are crystal orientations with fast recovery and slow crystal orientations, so that a structure recrystallized non-uniformly due to the difference. This intentionally created non-uniformity promotes the preferential development of the recrystallization texture in the intermediate recrystallization heat treatment [Step 9]. Some of the orientations that recover slowly become recrystallized structures, but the crystallographic orientations that recover quickly do not recrystallize.

  The copper alloy sheet of the present invention can satisfy the characteristics required for a copper alloy sheet for connectors, for example. In particular, the 0.2% proof stress is 500 MPa or more (preferably 600 MPa or more, more preferably 700 MPa or more), and the bending workability is the minimum bending radius (r: mm) that allows bending without cracks in a 90 ° W bending test. The value (r / t) divided by the plate thickness (t: mm) is 1 or less, and the electrical conductivity satisfies 30% IACS or more (preferably 35% IACS or more, more preferably 40% IACS or more). Furthermore, with regard to the stress relaxation resistance, a satisfactory characteristic is achieved that the stress relaxation rate (SR) can be satisfied by 30% or less (preferably 25% or less) by a measurement method of holding at 150 ° C. for 1000 hours, which will be described later. can do.

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

Example 1
As shown in the composition in the column of alloy components in Table 1-1, at least one or two of Ni and Co are added in a total amount of 0.5 to 5.0 mass%, and Si is set to 0.1 to 1.5 mass%. The alloy which contains and the remainder which consists of Cu and an inevitable impurity was melt | dissolved with the high frequency melting furnace, this was cast, and the ingot was obtained. Thereafter, homogenization heat treatment at 700 ° C. to 1020 ° C. for 10 minutes to 10 hours, hot rolling at a processing temperature of 500 to 1020 ° C. and a processing rate of 30 to 98%, water cooling, and cold rolling at 50 to 99% In this order, this state is used as a providing material, and the copper alloy sheet materials of Invention Examples 1-1 to 1-19 and Comparative Examples 1-1 to 1-9 are provided in any of the following processes A to F. A sample was produced.

(Process A)
Heat treatment held at 600 to 900 ° C. for 10 seconds to 5 minutes, cold working at a processing rate of 5 to 55%, intermediate holding for 1 second to 20 hours at (P-200) ° C. to (P-10) ° C. A recrystallization heat treatment, a final solution heat treatment is performed at (P + 10) ° C. or higher and (P + 150) ° C. or lower for 1 second to 1 minute. Thereafter, aging precipitation heat treatment at 350 to 600 ° C. for 5 minutes to 20 hours, finish rolling at a processing rate of 2 to 45%, and temper annealing that is maintained at 300 to 700 ° C. for 10 seconds to 2 hours are performed.

(Process B)
Heat treatment held at 600 to 900 ° C. for 10 seconds to 5 minutes, cold working at a processing rate of 5 to 55%, intermediate holding for 1 second to 20 hours at (P-200) ° C. to (P-10) ° C. A recrystallization heat treatment, a final solution heat treatment is performed at (P + 10) ° C. or higher and (P + 150) ° C. or lower for 1 second to 1 minute. Thereafter, rolling at a processing rate of 2 to 40%, aging precipitation heat treatment at 350 to 600 ° C. for 5 minutes to 20 hours, finish rolling at a processing rate of 2 to 45%, and holding at 300 to 700 ° C. for 10 seconds to 2 hours. Perform temper annealing.

(Process C)
Heat treatment held at 600 to 900 ° C. for 10 seconds to 5 minutes, cold working at a processing rate of 5 to 55%, intermediate holding for 1 second to 20 hours at (P-200) ° C. to (P-10) ° C. A recrystallization heat treatment, a final solution heat treatment is performed at (P + 10) ° C. or higher and (P + 150) ° C. or lower for 1 second to 1 minute. Thereafter, an aging precipitation heat treatment is performed at 350 to 600 ° C. for 5 minutes to 20 hours.

(Process D)
Heat treatment held at 600 to 900 ° C. for 10 seconds to 5 minutes, cold working at a processing rate of 5 to 55%, intermediate holding for 1 second to 20 hours at (P-200) ° C. to (P-10) ° C. A recrystallization heat treatment, a final solution heat treatment is performed at (P + 10) ° C. or higher and (P + 150) ° C. or lower for 1 second to 1 minute. Thereafter, rolling at a processing rate of 2 to 45% and aging precipitation heat treatment at 350 to 600 ° C. for 5 minutes to 20 hours are performed.

(Process E)
Intermediate recrystallization heat treatment held at (P-200) ° C. to (P-10) ° C. for 1 second to 20 hours, and final solution heat treatment held at (P + 10) ° C. to (P + 150) ° C. for 1 second to 1 minute. I do. Thereafter, aging precipitation heat treatment at 350 to 600 ° C. for 5 minutes to 20 hours, finish rolling at a processing rate of 2 to 45%, and temper annealing that is maintained at 300 to 700 ° C. for 10 seconds to 2 hours are performed.

(Process F)
Heat treatment held at 600 to 900 ° C. for 10 seconds to 5 minutes, cold working at a processing rate of 5 to 55%, and final solution heat treatment held at (P + 10) ° C. to (P + 150) ° C. for 1 second to 1 minute. . Thereafter, aging precipitation heat treatment at 350 to 600 ° C. for 5 minutes to 20 hours, finish rolling at a processing rate of 2 to 45%, and temper annealing that is maintained at 300 to 700 ° C. for 10 seconds to 2 hours are performed.

  After each heat treatment and rolling, acid cleaning and surface polishing were performed according to the state of oxidation and roughness of the material surface, and correction with a tension leveler was performed according to the shape.

  The following property investigation was conducted on this specimen. Here, the thickness of the test material was 0.15 mm. The results of Examples of the present invention are shown in Table 1-1, and the results of Comparative Examples are shown in Table 1-2.

a. Area ratio of the area of the atomic plane with the (111) plane facing TD:
By the EBSD method, measurement was performed in a measurement region of about 500 μm square under the condition that the scan step was 0.5 μm. The measurement area was adjusted based on the inclusion of 200 or more crystal grains. As described above, the (111) plane whose normal is TD, which is each ideal orientation, and the atomic plane whose angle between the normal of the (111) plane and TD is within 20 ° are combined. For these (in combination, the region of the atomic plane with the (111) plane facing the aforementioned TD), the total area ratio of these was calculated by the following equation.
Area ratio (%) = {(total of the area of the atomic plane in which the angle between the normal of (111) plane and TD is within 20 °) / total measurement area} × 100
In the following tables, this is simply indicated as “area ratio (%)”.
In addition, TSL OIM5.0HIKARI was used as an EBSD measuring apparatus.

b. Bending workability:
Cut into a width of 10 mm and a length of 25 mm perpendicular to the rolling direction, and W-bended so that the axis of bending is perpendicular to the rolling direction is GW (Good Way) and W-bent so as to be parallel to the rolling direction. The thing was made into BW (Bad Way), the bending part was observed with the optical microscope of 50 time, and the presence or absence of the crack was investigated.
Bending part has no cracks and wrinkles are “good (◎)”, no cracks are large but wrinkles are practically acceptable, “good (○)”, and those with cracks are “impossible ( ×) ”. The bending angle of each bent portion was 90 °, and the inner radius of the bent portion was 0.15 mm.

c. 0.2% yield strength [YS]:
Three test pieces of JIS Z 2201-13B cut out from the rolling parallel direction were measured according to JIS Z2241, and the average value was shown.

d: Conductivity [EC]:
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.

e. Stress relaxation rate [SR]:
Japan Copper and Brass Association JCBA T309: 2001 (This is a tentative standard. The old standard was “The Japan Electronic Materials Industry Standard ESMA-3003”), as shown below, at 150 ° C. for 1000 hours. It measured on the conditions after holding | maintenance. An initial stress of 80% of the proof stress was applied by the cantilever method.

FIG. 1 is an explanatory diagram of a stress relaxation resistance test method, in which (a) shows a state before heat treatment and (b) shows a state after heat treatment. As shown in FIG. 1A, the position of the test piece 1 when an initial stress of 80% of the proof stress is applied to the test piece 1 held in a cantilever manner on the test stand 4 is a distance of δ ₀ from the reference. is there. This is held in a thermostatic bath at 150 ° C. for 1000 hours (heat treatment in the state of the test piece 1), and the position of the test piece 2 after removing the load is determined from the reference H _t as shown in FIG. Is the distance. 3 is a test piece when no stress is applied, and its position is a distance H ₁ from the reference. From this relationship, the stress relaxation rate (%) was calculated as (H _t −H ₁ ) / (δ ₀ −H ₁ ) × 100. In the equation, δ ₀ is the distance from the reference to the test piece 1, H ₁ is the distance from the reference to the test piece 3, and H _t is the distance from the reference to the test piece 2.

As shown in Table 1-1, Invention Examples 1-1 to 1-19 were excellent in bending workability, yield strength, electrical conductivity, and stress relaxation resistance.
On the other hand, as shown in Table 1-2, when the provisions of the present invention were not satisfied, the characteristics were inferior.
That is, in Comparative Example 1-1, since the total amount of Ni and Co was small, the density of the compound (precipitate) contributing to precipitation hardening was lowered and the strength was inferior. Further, Si that does not form a compound with Ni or Co was excessively dissolved in the metal structure, resulting in poor conductivity. Since Comparative Example 1-2 had a large total amount of Ni and Co, the conductivity was inferior. Comparative Example 1-3 was inferior in strength due to a small amount of Si. Comparative Example 1-4 was inferior in electrical conductivity because of a large amount of Si.
In Comparative Examples 1-5 to 1-9, the ratio of the (111) plane facing TD was high, and the bending workability was poor. In particular, remarkable cracks were observed in BW bending.

Example 2
With respect to the copper alloy having the composition shown in the column of alloy components in Table 2 and the balance consisting of Cu and inevitable impurities, the present invention examples 2-1 to 2-17 and comparative examples 2-1 to 2 were performed in the same manner as in Example 1. -3 copper alloy sheet material was manufactured, and the characteristics were examined in the same manner as in Example 1. The results are shown in Table 2.

As shown in Table 2, Invention Example 2-1 to Invention Example 2-17 were excellent in bending workability, yield strength, electrical conductivity, and stress relaxation resistance.
On the other hand, when the provisions of the present invention were not satisfied, the characteristics were inferior. That is, in Comparative Examples 2-1, 2-2, and 2-3 (both are comparative examples of the invention according to the above item (3)), the amount of addition of other elements other than Ni, Co, and Si is large. The conductivity was inferior.

Example 3
For the copper alloy having the balance shown in Table 3 with the balance being Cu and inevitable impurities, the ingot is subjected to homogenization heat treatment at 700 ° C. to 1020 ° C. for 10 minutes to 10 hours, and then hot-rolled in the same manner as in Example 1. Water cooling, 50-99% cold rolling, heat treatment maintained at 600-900 ° C. for 10 seconds to 5 minutes, and cold working with a processing rate of 5-55% were performed in this order.
Thereafter, an intermediate recrystallization heat treatment and a final solution heat treatment as shown in Table 4 were performed. Thereafter, aging precipitation heat treatment at 350 to 600 ° C. for 5 minutes to 20 hours, finish rolling at a processing rate of 2 to 45%, and temper annealing held at 300 to 700 ° C. for 10 seconds to 2 hours, Manufactured. The characteristics were investigated in the same manner as in Example 1. The results are shown in Table 4.

As shown in Table 4, Invention Example 3-1 to Invention Example 3-6 were excellent in bending workability, yield strength, electrical conductivity, and stress relaxation resistance.
On the other hand, when the provisions of the present invention were not satisfied, the characteristics were inferior. That is, in Comparative Example 3-1, since the temperature of the intermediate recrystallization heat treatment was low, the region where the (111) plane was directed to TD was increased, and the bendability was inferior. In Comparative Example 3-2, since the temperature of the intermediate recrystallization heat treatment was high, the region where the (111) plane was directed to TD increased, and the bendability was inferior. In Comparative Example 3-3, since the treatment time of the intermediate recrystallization heat treatment was long, the solute atoms became coarse precipitates, which were not sufficiently solid solution in the final solution heat treatment, and the yield strength was inferior. In Comparative Example 3-4, since the treatment temperature of the final solution heat treatment was low, the solid solution of solute atoms was insufficient and the yield strength was inferior. In Comparative Example 3-5, since the treatment temperature of the final solution heat treatment was high, the crystal grains became coarse and the yield strength was inferior. In Comparative Example 3-6, since the treatment time for the final solution heat treatment was long, the crystal grains became coarse and the yield strength was inferior. Moreover, since Comparative Example 3-5 and 3-6 had a large crystal grain size, bending wrinkles were large and were not good.

  As described above, according to the present invention, it is possible to realize a characteristic that is very suitable as a material for an in-vehicle component such as a connector material or an electric / electronic device (particularly, the base material).

  Subsequently, in order to clarify the difference from the copper alloy sheet material according to the present invention, the copper alloy sheet material produced under the conventional production conditions, the copper alloy sheet material is produced under the conditions, and the same characteristic items as described above are evaluated. Went. In addition, the processing rate was adjusted so that the thickness of each board | plate material might become the same thickness as the said Example unless there is particular notice.

(Comparative Example 101) ... Conditions of JP2009-007666 A metal element similar to that of Invention Example 1-1 is blended, and an alloy composed of Cu and inevitable impurities is melted in a high-frequency melting furnace. This was cast at a cooling rate of 0.1 to 100 ° C./second to obtain an ingot. This was held at 900 to 1020 ° C. for 3 minutes to 10 hours, then hot worked, then water quenched, and chamfered to remove oxide scale. In the subsequent steps, the copper alloy c01 was manufactured by performing the processes of steps A-3 and B-3 described below.
The manufacturing process includes one or more solution heat treatments, and here, the process is classified before and after the last solution heat treatment, and the process up to the intermediate solution is A-3 process, It was set as B-3 process in the process after intermediate solution.

Step A-3: A cold working with a cross-sectional reduction rate of 20% or more is performed, a heat treatment is performed at 350 to 750 ° C. for 5 minutes to 10 hours, a cold working with a cross-sectional reduction rate of 5 to 50% is performed, and 800 A solution heat treatment is performed at ˜1000 ° C. for 5 seconds to 30 minutes.
Step B-3: cold working with a cross-section reduction rate of 50% or less, heat treatment at 400 to 700 ° C. for 5 minutes to 10 hours, and cold working with a cross-section reduction rate of 30% or less, 200 to Temper annealing is performed at 550 ° C. for 5 seconds to 10 hours.

  The obtained specimen c01 differs from the above examples in terms of production conditions in the presence or absence of intermediate recrystallization heat treatment [Step 9 in the present application], and has a high area ratio with the (111) plane facing TD, and bending workability. The result did not meet the required characteristics.

(Comparative Example 102) ... Conditions of Japanese Patent Application Laid-Open No. 2006-283059 The copper alloy having the composition of Example 1-1 of the present invention was melted in the atmosphere under charcoal coating in an electric furnace to determine whether casting was possible. . The molten ingot was hot-rolled to a thickness of 15 mm. Subsequently, the hot rolled material is subjected to cold rolling and heat treatment (cold rolling 1 → solution annealing, cold rolling 2 → aging treatment → cold rolling 3 → short annealing) to a predetermined thickness. A copper alloy sheet (c04) was produced.

  The obtained specimen c02 differs from Example 1 in terms of the manufacturing conditions in terms of the presence or absence of heat treatment [Step 7 in the present application] and intermediate recrystallization heat treatment [Step 9 in the present application], and the TD has a (111) plane. The area ratio facing was high, and the bending workability was not satisfied.

(Comparative Example 103) ... Conditions of Japanese Patent Application Laid-Open No. 2006-152392 The alloy having the composition of the present invention example 1-1 was melted under a charcoal coating in the atmosphere in a kryptor furnace and cast into a cast iron book mold. Thus, an ingot having a thickness of 50 mm, a width of 75 mm, and a length of 180 mm was obtained. Then, after chamfering the surface of the ingot, it was hot-rolled at a temperature of 950 ° C. until the thickness became 15 mm, and rapidly cooled into water from a temperature of 750 ° C. or higher. Next, after removing the oxide scale, cold rolling was performed to obtain a plate having a predetermined thickness.

  Subsequently, after using a salt bath furnace and performing a solution treatment by heating at a temperature for 20 seconds, the solution was rapidly cooled in water, and then cold-rolled sheets having various thicknesses were obtained by finish cold rolling in the latter half. At this time, as shown below, the cold-rolled sheet (c03) was obtained by variously changing the cold rolling processing rate (%). As shown below, these cold-rolled sheets were subjected to aging treatment at various temperatures (° C.) and times (hr).

Cold working rate: 95%
Solution treatment temperature: 900 ° C
Artificial age hardening temperature x time: 450 ° C x 4 hours Thickness: 0.6mm

  The obtained specimen c03 differs from Example 1 in terms of the manufacturing conditions in terms of the presence or absence of heat treatment [Step 7 in the present application] and intermediate recrystallization heat treatment [Step 9 in the present application], and the TD has a (111) plane. The area ratio facing was high, and the bending workability was not satisfied.

(Comparative Example 104) ... Conditions of JP-A-2008-223136 The copper alloy shown in Example 1 was melted and cast using a vertical continuous casting machine. A sample with a thickness of 50 mm was cut out from the obtained slab (thickness 180 mm), heated to 950 ° C., extracted, and hot rolling was started. At that time, the pass schedule was set so that the rolling rate in the temperature range of 950 ° C. to 700 ° C. was 60% or more and the rolling was performed even in the temperature range of less than 700 ° C. The final pass temperature of hot rolling is between 600 ° C and 400 ° C. The total hot rolling rate from the slab is about 90%. After hot rolling, the surface oxide layer was removed (faced) by mechanical polishing.

  Subsequently, after performing cold rolling, it used for the solution treatment. The temperature change during the solution treatment was monitored by a thermocouple attached to the sample surface, and the temperature raising time from 100 ° C. to 700 ° C. in the temperature raising process was determined. The ultimate temperature is adjusted within the range of 700 to 850 ° C. according to the alloy composition so that the average crystal grain size after solution treatment (the twin boundary is not regarded as a grain boundary) is 10 to 60 μm. The holding time in the temperature range of 850 ° C. was adjusted in the range of 10 sec to 10 min. Subsequently, the plate material after the solution treatment was subjected to intermediate cold rolling at a rolling rate and then subjected to an aging treatment. The aging treatment temperature was adjusted to a material temperature of 450 ° C., and the aging time was adjusted to a time when the hardness peaked at 450 ° C. according to the alloy composition. The optimum solution treatment conditions and aging treatment time according to such an alloy composition have been grasped by preliminary experiments. Next, finish cold rolling was performed at a rolling rate. About what performed finish cold rolling, the low temperature annealing which puts it in a 400 degreeC furnace for 5 minutes after that was given after that. In this way, a test material c04 was obtained. If necessary, chamfering was performed in the middle, and the thickness of the specimen was adjusted to 0.2 mm. The main production conditions are described below.

[Conditions of JP-A-2008-223136 Example 1]
Hot rolling rate at less than 700 ° C to 400 ° C: 56% (1 pass)
Before solution treatment Cold rolling rate: 92%
Intermediate cold rolling Cold rolling rate: 20%
Finish cold rolling Cold rolling rate: 30%
Temperature rising time from 100 ° C to 700 ° C: 10 seconds

  The obtained specimen c04 differs from Example 1 in terms of the manufacturing conditions in the presence or absence of heat treatment [Step 7 in the present application] and intermediate recrystallization heat treatment [Step 9 in the present application], and the TD has a (111) plane. The area ratio facing was high, and the bending workability was not satisfied.

DESCRIPTION OF SYMBOLS 1 Test piece when initial stress was applied 2 Test piece after removing load 3 Test piece when stress was not applied 4 Test stand

That is, the present invention provides the following solutions.
(1) The alloy composition is 0.5 to 5.0 mass% in total of any one or two of Ni and Co (provided that Co is 0.5 to 1.5 mass%), and Si is 0.00. 1 to 1.5 mass%, the balance has an alloy composition consisting of copper and inevitable impurities,
In the crystal orientation analysis in EBSD (Electron Back Scatter Diffraction) measurement, regarding the accumulation of atomic planes in the width direction (TD) of the rolled plate, the angle between the normal of the (111) plane and TD is A copper alloy sheet characterized in that the area ratio of a region having an atomic plane within 20 ° is 50% or less, the proof stress is 500 MPa or more, and the conductivity is 30% IACS or more.
( 2 ) Furthermore, it contains 0.005-2.0 mass% in total of at least one selected from the group consisting of Sn, Zn, Ag, Mn, B, P, Mg, Cr, Fe, Ti, Zr and Hf. The copper alloy sheet according to (1 ), characterized in that:
( 3 ) The copper alloy sheet according to (1) or (2) , which is a connector material.
( 4 ) A method for producing a copper alloy sheet according to any one of (1) to ( 3 ), wherein a copper alloy having an alloy composition that gives the copper alloy sheet is cast [step 1] and homogenized. Heat treatment [Step 2], Hot working [Step 3], Cold rolling [Step 6], Heat treatment [Step 7], Cold rolling [Step 8], Intermediate recrystallization heat treatment [Step 9], Final solution heat treatment [ Step 10] is performed in this order, followed by aging precipitation heat treatment [Step 11], and the intermediate recrystallization heat treatment [Step 9] is performed when (P− 200 ° C. to (P-10) ° C. for 1 second to 20 hours, and the final solution heat treatment [Step 10] is (P + 10) ° C. to (P + 150) ° C. for 1 second to 10 seconds. A method for producing a copper alloy sheet material, characterized by holding for a minute.
( 5 ) After the aging precipitation heat treatment [Step 11], cold rolling [Step 12] and temper annealing [Step 13] are performed in this order in the copper alloy sheet according to ( 4 ), Production method.

In the present invention, nickel (Ni), cobalt (Co), and silicon (Si), which are the first additive element group to be added to copper (Cu), are controlled by controlling the addition amount of Ni—Si, Co. It is possible to improve the strength of the copper alloy by precipitating a compound of -Si and Ni-Co-Si. The amount of addition is one or two of Ni and Co in total, preferably 0.5 to 5.0 mass%, more preferably 0.6 to 4.5 mass%, more preferably 0.8 to 4.0 mass%. The addition amount of Ni is preferably 1.5 to 4.2 mass%, more preferably 1.8 to 3.9 mass%, while the addition amount of Co is 0 . 5 to 1.5 mass%. In particular, when it is desired to increase the conductivity, it is preferable to make Co essential. By not adding too much the total amount of these elements, the electrical conductivity can be sufficiently secured, and by not making it too small, the strength can be sufficiently secured. The Si content is preferably 0.1 to 1.5 mass%, more preferably 0.2 to 1.2 mass%.

The following property investigation was conducted on this specimen. Here, the thickness of the test material was 0.15 mm. The results of Examples of the present invention and Reference Examples are shown in Table 1-1, and the results of Comparative Examples are shown in Table 1-2.

Example 2
For the copper alloy composed of Cu and inevitable impurities with the composition shown in the column of the alloy component in Table 2, in the same manner as in Example 1, test materials for the copper alloy sheet materials of the present invention example , reference example, and comparative example were used. Manufactured and examined for properties as in Example 1. The results are shown in Table 2.

Reference Example For a copper alloy having the composition shown in Table 3 and the balance being Cu and inevitable impurities, the ingot is subjected to homogenization heat treatment at 700 ° C. to 1020 ° C. for 10 minutes to 10 hours, and then hot rolled in the same manner as in Example 1. After that, it was cooled with water, cold-rolled at 50 to 99%, heat-treated at 600 to 900 ° C. for 10 seconds to 5 minutes, and cold worked at a processing rate of 5 to 55% in this order.
Thereafter, an intermediate recrystallization heat treatment and a final solution heat treatment as shown in Table 4 were performed. Thereafter, aging precipitation heat treatment at 350 to 600 ° C. for 5 minutes to 20 hours, finish rolling at a processing rate of 2 to 45%, and temper annealing held at 300 to 700 ° C. for 10 seconds to 2 hours, Manufactured. The characteristics were investigated in the same manner as in Example 1. The results are shown in Table 4.

As shown in Table 4, Reference Example 3-1 to Reference Example 3-6 were excellent in bending workability, yield strength, electrical conductivity, and stress relaxation resistance.
On the other hand, when the provisions of the present invention were not satisfied, the characteristics were inferior. That is, in Comparative Example 3-1, since the temperature of the intermediate recrystallization heat treatment was low, the region where the (111) plane was directed to TD was increased, and the bendability was inferior. In Comparative Example 3-2, since the temperature of the intermediate recrystallization heat treatment was high, the region where the (111) plane was directed to TD increased, and the bendability was inferior. In Comparative Example 3-3, since the treatment time of the intermediate recrystallization heat treatment was long, the solute atoms became coarse precipitates, which were not sufficiently solid solution in the final solution heat treatment, and the yield strength was inferior. In Comparative Example 3-4, since the treatment temperature of the final solution heat treatment was low, the solid solution of solute atoms was insufficient and the yield strength was inferior. In Comparative Example 3-5, since the treatment temperature of the final solution heat treatment was high, the crystal grains became coarse and the yield strength was inferior. In Comparative Example 3-6, since the treatment time for the final solution heat treatment was long, the crystal grains became coarse and the yield strength was inferior. Moreover, since Comparative Example 3-5 and 3-6 had a large crystal grain size, bending wrinkles were large and were not good.

(Comparative Example 102) ... Conditions with reference to Japanese Patent Application Laid-Open No. 2006-283059 The copper alloy having the composition of the invention example 1-1 was melted in the atmosphere under a charcoal coating in an electric furnace, and castability was determined. Judged. The molten ingot was hot-rolled to a thickness of 15 mm. Subsequently, the hot rolled material is subjected to cold rolling and heat treatment (cold rolling 1 → solution annealing, cold rolling 2 → aging treatment → cold rolling 3 → short annealing) to a predetermined thickness. A copper alloy sheet (c04) was produced.

That is, the present invention provides the following solutions.
(1) The alloy composition is 0.5 to 5.0 mass% in total of any one or two of Ni and Co (provided that Co is 0.5 to 1.5 mass%), and Si is 0.00. 1 to 1.5 mass%, the balance has an alloy composition consisting of copper and inevitable impurities,
In the crystal orientation analysis in EBSD (Electron Back Scatter Diffraction) measurement, regarding the accumulation of atomic planes in the width direction (TD) of the rolled plate, the angle between the normal of the (111) plane and TD is A copper alloy sheet characterized in that the area ratio of a region having an atomic plane within 20 ° is 50% or less, the proof stress is 500 MPa or more, and the conductivity is 30% IACS or more.
(2) Further, 0.005 to 2.0 mass% in total of at least one selected from the group consisting of Sn, Zn, Ag, Mn, B, P, Mg, Cr, Fe, Ti, Zr, and Hf is contained. The copper alloy sheet according to (1), characterized in that:
(3) The copper alloy sheet according to (1) or (2), which is a connector material.
(4) A method for producing a copper alloy sheet according to any one of (1) to (3), wherein the copper alloy has an alloy composition that gives the copper alloy sheet.
(A) a high-frequency melting furnace by dissolving the casting and the performing obtain ingots Casting process (described later [Step 1]),
(B) homogeneous Kanetsu processing step of performing 700 ℃ ~1020 ℃ for 10 minutes to 10 hours (to be described later [Step 2]),
(C) a hot rolling step performed at a processing rate of 30% to 98% at a processing temperature of 500 ° C. to 1020 ° C. ([Step 3] described later),
(D) Hiyakan圧extension step for 50% to 99% of the working ratio (described later [Step 6]),
(E) Netsusho management step of holding 600 ° C. to 900 ° C. for 10 seconds to 5 minutes (to be described later [Step 7]),
(F) a cold working step performed at a working rate of 5% to 55% (described later [Step 8]),
(G) a complete solid-solution temperature of the solute atoms in the case of a P ℃, (P-200) ℃ or more (P-10) ℃ intermediate recrystallization heat treatment step of holding 1 second to 20 hours at temperatures below ([Step 9] described later),
(H) with (P + 10) ° C. or more at (P + 0.99) ° C. or less, the final solution Netsusho management step of holding 1 second to 10 minutes (to be described later [Step 10]), subjected to in order,
Then, (i) the production method of the copper alloy sheet, characterized in that to facilities the 350 ° C. to 600 ° C. for 5 minutes to 20 hours performing aging precipitation heat treatment process (described later [Step 11]).
(5) after said aging precipitation heat treatment step (i), (j) Hiyakan圧extension step of finish rolling at a working ratio of 2% to 45% (to be described later [Step 12]), and (k) 300 ° C. method for producing a copper alloy sheet according to to 700 ° C. for 10 seconds to 2 hours retention to tempering sintered blunt process (described later [step 13]) is characterized in that applied to the order (4).

That is, the present invention provides the following solutions.
(1) Co 0.5~5.0mass% at total of 0.5～1.86Mass% or Ni and Co (provided that a 0.5 to 1. 86 mass% of Co), the Si 0 .1 to 1.5 mass%, the balance having an alloy composition consisting of copper and inevitable impurities,
In the crystal orientation analysis in EBSD (Electron Back Scatter Diffraction) measurement, regarding the accumulation of atomic planes in the width direction (TD) of the rolled plate, the angle between the normal of the (111) plane and TD is A copper alloy sheet characterized in that the area ratio of a region having an atomic plane within 20 ° is 50% or less, the proof stress is 500 MPa or more, and the conductivity is 30% IACS or more.
(2) Further, 0.005 to 2.0 mass% in total of at least one selected from the group consisting of Sn, Zn, Ag, Mn, B, P, Mg, Cr, Fe, Ti, Zr, and Hf is contained. The copper alloy sheet according to (1), characterized in that:
(3) The copper alloy sheet according to (1) or (2), which is a connector material.
(4) To a copper alloy having an alloy composition that gives the copper alloy sheet,
(A) a casting process for obtaining an ingot by melting and casting with a high-frequency melting furnace;
(B) A homogenization heat treatment step performed at 700 ° C. to 1020 ° C. for 10 minutes to 10 hours,
(C) a hot rolling step performed at a processing temperature of 500 ° C. to 1020 ° C. and a processing rate of 30% to 98%;
(D) a cold rolling process performed at a processing rate of 50% to 99%;
(E) a heat treatment step of holding at 600 ° C. to 900 ° C. for 10 seconds to 5 minutes,
(F) a cold working step performed at a working rate of 5% to 55%;
(G) an intermediate recrystallization heat treatment step of maintaining a temperature of (P-200) ° C. to (P-10) ° C. for 1 second to 20 hours when the complete solid solution temperature of the solute atoms is P ° C.,
(H) In the order of (P + 10) ° C. to (P + 150) ° C., a final solution heat treatment step of holding for 1 second to 10 minutes,
Any one of (1) to (3) obtained by (i) a method for producing a copper alloy sheet material which is then subjected to an aging precipitation heat treatment step performed at 350 ° C. to 600 ° C. for 5 minutes to 20 hours. The copper alloy sheet material according to item.
(5) After the aging precipitation heat treatment step (i) of (4), (j) a cold rolling step of finish rolling at a processing rate of 2% to 45%, and (k) 10 at 300 ° C. to 700 ° C. The copper alloy sheet according to any one of (1) to (3), wherein the copper alloy sheet is obtained by a method for producing a copper alloy sheet that is subjected to a temper annealing step in this order for 2 seconds to 2 hours.
( 6 ) A method for producing a copper alloy sheet according to any one of (1) to (3), wherein the copper alloy has an alloy composition that gives the copper alloy sheet.
(A) A casting step (to be described later [Step 1]) for obtaining an ingot by melting and casting with a high-frequency melting furnace,
(B) A homogenization heat treatment step ([Step 2] described later) performed at 700 ° C. to 1020 ° C. for 10 minutes to 10 hours,
(C) a hot rolling step performed at a processing rate of 30% to 98% at a processing temperature of 500 ° C. to 1020 ° C. ([Step 3] described later),
(D) a cold rolling step performed at a processing rate of 50% to 99% (described later [Step 6]),
(E) a heat treatment step of holding at 600 ° C. to 900 ° C. for 10 seconds to 5 minutes (described later [Step 7]),
(F) a cold working step performed at a working rate of 5% to 55% (described later [Step 8]),
(G) Intermediate recrystallization heat treatment step (described later) that is maintained for 1 second to 20 hours at a temperature of (P-200) ° C. or higher and (P-10) ° C. or lower when the complete solute temperature of solute atoms is P ° C. [Step 9]),
(H) A final solution heat treatment step (described below [Step 10]) that is held for 1 second to 10 minutes at (P + 10) ° C. or higher and (P + 150) ° C. or lower in order,
Thereafter, (i) an aging precipitation heat treatment step ([Step 11] described later) performed at 350 ° C. to 600 ° C. for 5 minutes to 20 hours is performed.
( 7 ) (j) After the aging precipitation heat treatment step of (i), (j) a cold rolling step of finishing rolling at a processing rate of 2% to 45% (described later [Step 12]), and (k) 300 ° C. to The method for producing a copper alloy sheet according to ( 6 ), wherein a temper annealing step (to be described later [Step 13]) held at 700 ° C. for 10 seconds to 2 hours is performed in this order.

(Alloy composition, etc.)
・ Ni, Co, Si
Copper or copper alloy is used as the connector material of the present invention. In addition to copper, copper alloys such as phosphor bronze, brass, white, beryllium copper, corson alloy (Cu-Ni-Si), etc. as those having electrical conductivity, mechanical strength and heat resistance required for connectors Is preferred. In particular, when it is desired to obtain an area ratio satisfying the specific crystal orientation accumulation relationship of the present invention, a pure copper-based material, a beryllium copper, and a precipitation type alloy including a Corson alloy are preferable. Furthermore, as determined on the cutting edge of the small terminal material, in order to achieve both high strength and high conductivity, C u-Ni-Co- Si -based, Cu-Co-Si-based precipitation copper alloy is preferred .
This is because, in a solid solution type alloy such as phosphor bronze or brass, a minute region having a Cube orientation in the cold-rolled material, which becomes a nucleus of Cube orientation grain growth in crystal grain growth during heat treatment, is reduced. This is because in a system with low stacking fault energy such as phosphor bronze and brass, a shear band is likely to develop during cold rolling.

In the present invention, the copper-nickel as a first additive element group to be added to the (Cu) (Ni) and cobalt (Co) and silicon (Si), by controlling the respective amount, C o-Si, Ni—Co—Si compounds can be precipitated to improve the strength of the copper alloy. The amount of addition is one or two of Ni and Co in total, preferably 0.5 to 5.0 mass%, more preferably 0.6 to 4.5 mass%, more preferably 0.8 to 4.0 mass%. The addition amount of Ni is preferably 1.5 to 4.2 mass%, more preferably 1.8 to 3.9 mass%, while the addition amount of Co is 0.5 to 1. 86 mass%. In particular, when it is desired to increase the conductivity, it is preferable to make Co essential. By not adding too much the total amount of these elements, the electrical conductivity can be sufficiently secured, and by not making it too small, the strength can be sufficiently secured. The Si content is preferably 0.1 to 1.5 mass%, more preferably 0.2 to 1.2 mass%.

The effect of adding each element is shown below. Mg, Sn, Zn is, C u-Ni-Co- Si system, stress relaxation resistance is improved by adding to the Cu-Co-Si based copper alloy. The stress relaxation resistance is further improved by a synergistic effect when each of them is added together than when they are added alone. In addition, there is an effect of remarkably improving solder embrittlement.

(Comparative Example 102) ... Conditions of Japanese Patent Application Laid-Open No. 2006-283059 The copper alloy having the composition of Example 1-1 of the present invention was melted in the atmosphere under charcoal coating in an electric furnace to determine whether casting was possible. . The molten ingot was hot-rolled to a thickness of 15 mm. Subsequently, the hot rolled material is subjected to cold rolling and heat treatment (cold rolling 1 → solution annealing, cold rolling 2 → aging treatment → cold rolling 3 → short annealing) to a predetermined thickness. We were prepared of a copper alloy sheet (c0 2).

That is, the present invention provides the following solutions.
(1) Co is 0.5 to 1.86 mass% or the total of Ni and Co is 0.5 to 5.0 mass% (provided that Co is 0.5 to 1.86 mass%), and Si is 0.1 ~ 1.5 mass%, the balance has an alloy composition consisting of copper and inevitable impurities,
In the crystal orientation analysis in EBSD (Electron Back Scatter Diffraction) measurement, regarding the accumulation of atomic planes in the width direction (TD) of the rolled plate, the angle between the normal of the (111) plane and TD is A copper alloy sheet characterized in that the area ratio of a region having an atomic plane within 20 ° is 50% or less, the proof stress is 500 MPa or more, and the conductivity is 40 % IACS or more.
(2) Further, 0.005 to 2.0 mass% in total of at least one selected from the group consisting of Sn, Zn, Ag, Mn, B, P, Mg, Cr, Fe, Ti, Zr, and Hf is contained. The copper alloy sheet according to (1), characterized in that:
(3) The copper alloy sheet according to (1) or (2), which is a connector material.
(4) To a copper alloy having an alloy composition that gives the copper alloy sheet,
(A) a casting process for obtaining an ingot by melting and casting with a high-frequency melting furnace;
(B) A homogenization heat treatment step performed at 700 ° C. to 1020 ° C. for 10 minutes to 10 hours,
(C) a hot rolling step performed at a processing temperature of 500 ° C. to 1020 ° C. and a processing rate of 30% to 98%;
(D) a cold rolling process performed at a processing rate of 50% to 99%;
(E) a heat treatment step of holding at 600 ° C. to 900 ° C. for 10 seconds to 5 minutes,
(F) a cold working step performed at a working rate of 5% to 55%;
(G) an intermediate recrystallization heat treatment step of maintaining a temperature of (P-200) ° C. to (P-10) ° C. for 1 second to 20 hours when the complete solid solution temperature of the solute atoms is P ° C.,
(H) In the order of (P + 10) ° C. to (P + 150) ° C., a final solution heat treatment step of holding for 1 second to 10 minutes,
Any one of (1) to (3) obtained by (i) a method for producing a copper alloy sheet material which is then subjected to an aging precipitation heat treatment step performed at 350 ° C. to 600 ° C. for 5 minutes to 20 hours. The copper alloy sheet material according to item.
(5) After the aging precipitation heat treatment step (i) of (4), (j) a cold rolling step of finish rolling at a processing rate of 2% to 45%, and (k) 10 at 300 ° C. to 700 ° C. The copper alloy sheet according to any one of (1) to (3), wherein the copper alloy sheet is obtained by a method for producing a copper alloy sheet that is subjected to a temper annealing step in this order for 2 seconds to 2 hours.
(6) A method for producing a copper alloy sheet according to any one of (1) to (3), wherein the copper alloy has an alloy composition that gives the copper alloy sheet.
(A) A casting step (to be described later [Step 1]) for obtaining an ingot by melting and casting with a high-frequency melting furnace,
(B) A homogenization heat treatment step ([Step 2] described later) performed at 700 ° C. to 1020 ° C. for 10 minutes to 10 hours,
(C) a hot rolling step performed at a processing rate of 30% to 98% at a processing temperature of 500 ° C. to 1020 ° C. ([Step 3] described later),
(D) a cold rolling step performed at a processing rate of 50% to 99% (described later [Step 6]),
(E) a heat treatment step of holding at 600 ° C. to 900 ° C. for 10 seconds to 5 minutes (described later [Step 7]),
(F) a cold working step performed at a working rate of 5% to 55% (described later [Step 8]),
(G) Intermediate recrystallization heat treatment step (described later) that is maintained for 1 second to 20 hours at a temperature of (P-200) ° C. or higher and (P-10) ° C. or lower when the complete solute temperature of solute atoms is P ° C. [Step 9]),
(H) A final solution heat treatment step (described below [Step 10]) that is held for 1 second to 10 minutes at (P + 10) ° C. or higher and (P + 150) ° C. or lower in order,
Thereafter, (i) an aging precipitation heat treatment step ([Step 11] described later) performed at 350 ° C. to 600 ° C. for 5 minutes to 20 hours is performed.
(7) After the aging precipitation heat treatment step of (i), (j) a cold rolling step of finishing rolling at a processing rate of 2% to 45% (described later [Step 12]), and (k) 300 ° C. to The method for producing a copper alloy sheet according to (6), wherein a temper annealing step (described later [Step 13]) that is held at 700 ° C. for 10 seconds to 2 hours is performed in this order.

Claims (6)

  In the crystal orientation analysis in EBSD (Electron Back Scatter Diffraction) measurement, regarding the accumulation of atomic planes in the width direction (TD) of the rolled plate, the angle between the normal of the (111) plane and TD is A copper alloy sheet characterized in that the area ratio of a region having an atomic plane within 20 ° is 50% or less, the proof stress is 500 MPa or more, and the conductivity is 30% IACS or more.   One or two of Ni and Co in total 0.5 to 5.0 mass%, Si 0.1 to 1.5 mass%, the balance has an alloy composition consisting of copper and inevitable impurities, In the crystal orientation analysis in EBSD (Electron Back Scatter Diffraction) measurement, regarding the accumulation of atomic planes in the width direction (TD) of the rolled plate, the angle between the normal of the (111) plane and TD is A copper alloy sheet characterized in that the area ratio of a region having an atomic plane within 20 ° is 50% or less, the proof stress is 500 MPa or more, and the conductivity is 30% IACS or more.   Containing one or two of Ni and Co in a total amount of 0.5 to 5.0 mass%, Si containing 0.1 to 1.5 mass%, Sn, Zn, Ag, Mn, B, P, Mg, A total of at least one selected from the group consisting of Cr, Fe, Ti, Zr and Hf is contained in an amount of 0.005 to 2.0 mass%, with the balance being an alloy composition consisting of copper and inevitable impurities. EBSD (Electron Back) In crystal orientation analysis in scatter diffraction (electron backscattering diffraction) measurement, regarding the accumulation of atomic planes in the width direction (TD) of the rolled plate, the angle between the normal of the (111) plane and TD is within 20 °. A copper alloy sheet, wherein the area ratio of a region having a certain atomic plane is 50% or less, the proof stress is 500 MPa or more, and the conductivity is 30% IACS or more.   It is a material for connectors, The copper alloy board | plate material of any one of Claims 1-3 characterized by the above-mentioned.   It is a method of manufacturing the copper alloy sheet | seat of any one of Claims 1-4, Comprising: It casts into the copper alloy of the alloy composition which gives the said copper alloy sheet | seat [Step 1], Homogenization heat treatment [Step 2], hot working [step 3], cold rolling [step 6], heat treatment [step 7], cold rolling [step 8], intermediate recrystallization heat treatment [step 9], final solution heat treatment [step 10]. Are applied in this order, followed by aging precipitation heat treatment [Step 11], and the intermediate recrystallization heat treatment [Step 9] is (P-200) ° C. when the complete solid solution temperature of the solute atoms is P ° C. As described above, the temperature is maintained at a temperature of (P-10) ° C. or lower for 1 second to 20 hours, and the final solution heat treatment [Step 10] is held at (P + 10) ° C. to (P + 150) ° C. for 1 second to 10 minutes. A method for producing a copper alloy sheet.   6. The method for producing a copper alloy sheet according to claim 5, wherein after the aging precipitation heat treatment [Step 11], cold rolling [Step 12] and temper annealing [Step 13] are performed in this order.