TWI621721B - Copper alloy sheet, connector, and method for manufacturing copper alloy sheet - Google Patents

Abstract

The present invention provides a copper alloy sheet material having high electrical conductivity and high strength in any one of 0°, 45° or 90° directions from the rolling direction toward the rolling vertical direction, and a connector using the same, and A method of manufacturing the copper alloy sheet.

In the copper alloy sheet material of the present invention, the connector using the same, and the method for producing the copper alloy sheet material, the copper alloy sheet material has the following composition: one or two of Ni and Co in total of 1.80 to 8.00% by mass. And 0.40 to 2.00% by mass of Si, and a total of 0.000 to 2.000% by mass of at least one element selected from the group consisting of Sn, Zn, Ag, Mn, P, Mg, Cr, Zr, Fe, and Ti, The remainder consists of copper and unavoidable impurities. The conductivity of the copper alloy sheet is 20-40% IACS, and the tensile strength is 0°, 45°, 90° from the rolling direction toward the vertical direction of the rolling. Both are 1020~1400MPa.

Description

Copper alloy sheet, connector, and method for manufacturing copper alloy sheet

The present invention relates to a copper alloy sheet material and a connector using the same, and a method of manufacturing the copper alloy sheet material.

With the miniaturization and thinning of electronic equipment, terminals or connectors for connecting electronic equipment and external equipment are required to be further miniaturized. Moreover, since the terminals or connectors are also inserted or removed dozens of times a day, the strength or fatigue resistance (repetition characteristics) of the spring portion is also required. Since the terminal or the connector must have strength or electrical conductivity, it is often made of a copper alloy. Therefore, a copper alloy material for a terminal or a connector which is small in size and excellent in strength and fatigue resistance is desired.

In particular, the terminal or the connector is manufactured by punching and press-forming a plate of a copper alloy. At this time, in many cases, the stress load direction of the spring portion of the terminal or the connector becomes 90° from the rolling direction (RD; Rolling Direction) of the copper alloy sheet toward the rolling vertical direction (TD; Transverse Direction). Direction or direction of 45°. Therefore, the copper alloy sheet for the terminal or the connector is required to have excellent fatigue resistance in any of the directions. Moreover, if the length of the spring portion becomes shorter as the terminal or the connector is miniaturized, the stress applied to the spring portion becomes large. Therefore, in addition to the above-mentioned fatigue resistance characteristics of copper alloy sheets are required In addition to good, copper alloy sheets are also required to be permanently deformed even if they are given high stress.

Conventionally, as a copper alloy for springs, a phosphor bronze system is used at most. The phosphor bronze-based spring copper alloy is excellent in strength or fatigue resistance, but the electrical conductivity is as low as about 10% IACS. Therefore, it is considered that there is a case where the use of a copper bronze alloy for a phosphor bronze type in a terminal which is required to be small and highly reliable in the future is limited. The reason for this is that a small-sized and highly reliable terminal spring material is required to have a conductivity of 20% IACS or more.

A Cu-Ni-Si-based copper alloy, a so-called Carson-based alloy system, has been developed as a lead frame and is also used as an alloy for a connector. The conductivity of the Cassis alloy to date is better than that of the phosphor bronze system. However, the strength or fatigue resistance of the Carson-based alloy to date does not satisfy the recent requirements. In particular, the fatigue resistance is good even in the direction from the rolling direction to the rolling vertical direction of 0° (ie, the rolling direction), and the direction from the rolling direction to the rolling vertical direction of 45° or 90°. Also poor.

According to the technical direction of such an electronic device, it is necessary to have a material having high electrical conductivity and excellent strength and fatigue resistance in either of the 0°, 45°, or 90° directions from the rolling direction toward the rolling vertical direction. .

Patent Document 1 proposes a method of selecting an alloy composition containing a component containing a Cu—Ni—Sn-based alloy and subjecting it to aging precipitation hardening by a specific step, thereby achieving good fatigue properties without lowering electrical conductivity. Copper alloy.

Patent Document 2 proposes a method of adjusting a crystal grain size of a Cu-Sn-based alloy and a finish rolling condition to form a high-strength copper alloy.

Patent Document 3 proposes a method of producing high strength by using a specific step in the case where the concentration of Ni in the Cu-Ni-Si alloy is high.

Patent Document 4 proposes a method of selecting a combination of alloys containing a component containing a Cu-Ti-based alloy and subjecting it to aging precipitation hardening by a specific step, thereby producing high strength.

Patent Document 5 proposes a method of obtaining a Cu-Ni-Si alloy strip by using a specific manufacturing step, and having a specific {110}<001> azimuth density and KAM (Karnel Average Misorientation). The value of the supporting angle is increased, and the deep drawing workability and the fatigue resistance are improved.

Patent Document 6 proposes a copper-based precipitation type alloy plate material for a Cu-Ni-Si-based contact material, which has a tensile strength in a rolling direction and an angle of 45° with respect to a rolling direction. The maximum value of each difference between the three tensile strengths of the tensile strength at an angle of 90° with respect to the rolling direction is 100 MPa or less.

Patent Document 7 proposes a method of controlling the area ratio of the Cube orientation and the BR orientation of the Cu-Ni-Si alloy to have high strength, bending workability, stress relaxation resistance, and fatigue resistance. Improved features.

[Patent Document 1] JP-A-63-312937

[Patent Document 2] Japanese Laid-Open Patent Publication No. 2002-294367

[Patent Document 3] Japanese Laid-Open Patent Publication No. 2006-152392

[Patent Document 4] Japanese Laid-Open Patent Publication No. 2011-132594

[Patent Document 5] Japanese Patent Laid-Open Publication No. 2012-122114

[Patent Document 6] Japanese Patent Laid-Open Publication No. 2008-095186

[Patent Document 7] Japanese Laid-Open Patent Publication No. 2012-246549

However, in Patent Documents 1 to 4, although high strength can be obtained as compared with a conventional copper alloy, the electrical conductivity is still low depending on the alloy system and the production method.

In Patent Document 5, although deep drawing workability and fatigue resistance are obtained, there is still room for improvement in strength and electrical conductivity.

In Patent Document 6, although high electrical conductivity is obtained, there is still room for improvement in terms of high strength.

In Patent Document 7, although bending workability, stress relaxation resistance, and fatigue resistance are obtained, there is still room for improvement in terms of high strength and high electrical conductivity.

Further, in the above-mentioned Patent Documents 1 to 7, the high-intensity is set in any of 0°, 45°, or 90° from the rolling direction toward the vertical direction of the rolling, and it is not actually It is clear whether the tensile strength is high in either direction.

Therefore, a copper alloy sheet material having good electrical conductivity and having high tensile strength in any of 0, 45, or 90° from the rolling direction toward the vertical direction of the rolling is required.

In view of the above problems in the prior art, an object of the present invention is to provide a copper alloy sheet material having a high electrical conductivity and a direction of 0°, 45° or 90° from the rolling direction toward the vertical direction of the rolling. In any of the directions, the strength is high, and it is preferred that the fatigue resistance is excellent in either direction. Further, an object of the present invention is to provide a connector using the copper alloy sheet material and a method of producing the copper alloy sheet material. In particular, it is an object of the present invention to provide a thin-plate spring material and a relay for a camera module, in addition to a connector for external connection represented by a dock connector or a USB connector. A copper alloy plate material such as a movable piece, a connector using the same, and a method of manufacturing the copper alloy plate material.

In order to solve the above problems, the inventors of the present invention have conducted intensive studies and found that a copper alloy sheet having a specific Cu-(Ni, Co)-Si alloy composition and manufactured under specific manufacturing conditions has good electrical conductivity. High strength can be produced in any of the 0°, 45° or 90° directions from the rolling direction toward the rolling vertical direction. The present invention has been completed based on this finding.

That is, according to the present invention, the following means are provided.

(1) A copper alloy sheet material having a composition of any one or two of Ni and Co in a total amount of 1.80 to 8.00% by mass, Si of 0.40 to 2.00% by mass, and a total of 0.000 to 2.000% by mass. The at least one element selected from the group consisting of Sn, Zn, Ag, Mn, P, Mg, Cr, Zr, Fe, and Ti, the remainder being composed of copper and unavoidable impurities; the conductive of the copper alloy sheet The rate is 20 to 40% IACS or more, and the tensile strength in the direction from the rolling direction (RD) to the rolling vertical direction (TD) of 0°, 45°, and 90° is 1020 to 1400 MPa.

(2) The copper alloy sheet according to item (1), which comprises a total of 0.005 to 2.000 mass% selected from the group consisting of Sn, Zn, Ag, Mn, P, Mg, Cr, Zr, Fe, and Ti. At least 1 element.

(3) A connector comprising the copper alloy sheet material of (1) or (2).

(4) A method for producing a copper alloy sheet, which comprises the steps of: a melting and a casting step of melting and casting a copper alloy containing a total of 1.80 to 8.00% by mass of Ni and Co. One or two kinds, 0.40 to 2.00% by mass of Si, and a total of 0.000 to 2.000% by mass selected from the group consisting of Sn, Zn, Ag, Mn, P, Mg, Cr, Zr, Fe, and Ti At least one element, the remainder consisting of copper and unavoidable impurities; homogenization heat treatment step, which is carried out at 900~1040 ° C for more than 1 hour; thermal processing step, self-heating The temperature range from the beginning to the end of the work is 500~1040 °C, the processing rate is 10~90%; the intermediate cold rolling step, the processing rate is 0~95%; the heat treatment step is carried out at 300~430 °C for 5 minutes to 10 The heat treatment of the hour; and the final cold rolling step, the processing rate is 60 to 99%.

(5) The method for producing a copper alloy sheet according to the item (4), wherein the copper alloy for the melting and casting step contains a total of 0.005 to 2.000% by mass selected from the group consisting of Sn, Zn, Ag, Mn, P, and Mg. At least one element selected from the group consisting of Cr, Zr, Fe, and Ti.

(6) The method for producing a copper alloy sheet according to item (4) or (5), wherein after the final cold rolling step, the relaxation annealing is performed at 200 to 500 ° C for 5 seconds to 2 hours.

The copper alloy sheet material of the present invention is preferably used for a camera module, in addition to being preferably used for connecting an external connector represented by a dock connector or a USB connector. Thin plate spring material, movable piece of relay, etc.

The copper alloy sheet material of the present invention has a strength significantly higher than the conventional one in any one of the 0°, 45° or 90° directions from the rolling direction to the rolling vertical direction in the direction of the stress loading direction of the spring. It can be used as a material for springs whose characteristics are not easily deteriorated. Therefore, for example, it is preferable as a connection device.

Further, according to the method for producing a copper alloy sheet material of the present invention, a copper alloy sheet material having the above-described excellent characteristics can be preferably produced.

The above and other features and advantages of the present invention will become more apparent from the aspects of the appended claims.

1‧‧‧copper alloy sheet

20‧‧‧Test piece for measuring tensile strength and fatigue resistance from the rolling direction (RD) to the rolling vertical direction (TD) of 0°

21‧‧‧Test piece for measuring tensile strength and fatigue resistance from the rolling direction (RD) to the rolling vertical direction (TD) of 45°

22‧‧‧Test piece for measuring tensile strength and fatigue resistance from the rolling direction (RD) to the rolling vertical direction (TD) of 90°

Figure 1 shows the copper alloy sheet and rolling direction (RD), rolling vertical direction Schematic diagram of the relationship between (TD) and the vertical direction (ND) of the rolling surface.

Fig. 2 is a schematic view showing a test piece in a direction of 0°, 45°, and 90° from the rolling direction toward the vertical direction of rolling as a test piece in a tensile test and a fatigue test.

Figure 3 is an explanatory diagram of local elongation. A stress-strain curve of the invention example 205 in the 0° direction is shown as a representative example in FIG. The partial elongation (e _L ) refers to the elongation after the uniform elongation (e _U ) is shown until the test material is broken.

Fig. 4(A) is a {100} pole diagram using X-rays in Inventive Example 205, Fig. 4(B) is a {100} pole diagram using X-rays in Comparative Example 256, and Fig. 4(C) is on comparison. Example 257 uses a {100} pole map of X-rays.

A preferred embodiment of the copper alloy sheet of the present invention will be described in detail. Here, the term "copper alloy material" means that the copper alloy material is processed into a specific shape (for example, a plate, a strip, a foil, a rod, a wire, etc.). Here, the term "sheet" means a tube having a specific thickness and a stable shape and widening in the plane direction, and broadly means a tube comprising a strip or a foil and a tubular shape.

Fig. 1 shows the relationship between the copper alloy sheet material 1 of the present embodiment, the rolling direction (RD), the rolling vertical direction (TD), and the rolling plane perpendicular direction (ND; Normal Direction, normal direction). The rolling direction is a direction in which a sheet material is rolled by a rolling roll or the like when a copper alloy sheet material is produced. On the other hand, the rolling vertical direction is perpendicular to the rolling direction and parallel to the rolling surface. The vertical direction of the rolling surface is perpendicular to the rolling surface. The industrial copper alloy sheet is manufactured and shipped while being rolled into a roll. Therefore, Yu Gang made copper After the gold plate, usually the length direction of the plate is the rolling direction, and the width direction of the plate is the vertical direction of the rolling.

The copper alloy sheet material of the present embodiment has a specific alloy composition, and has a conductivity of 20 to 40% IACS or more, and is 0° and 45° from the rolling direction (RD) toward the rolling vertical direction (TD). The tensile strength in the direction of 90° is 1020 to 1400 MPa, and the specific alloy composition contains one or two of Ni and Co and Si in a specific amount, and is optionally contained in a specific amount selected from the group consisting of Sn and Zn. At least one element selected from the group consisting of Ag, Mn, P, Mg, Cr, Zr, Fe, and Ti, and the remainder is composed of copper and unavoidable impurities. Here, the above three directions are directions on the surface parallel to the rolling surface (that is, the surface formed by the rolling direction and the rolling vertical direction). In Fig. 2, the test piece 20 in the direction from the rolling direction (RD) toward the rolling vertical direction (TD) of 0° from the copper alloy sheet material 1 of the present embodiment, and the self-rolling direction (RD) are shown by broken lines. The test piece 21 in the direction in which the rolling vertical direction (TD) is 45°, and the test piece 22 in the direction from the rolling direction (RD) toward the rolling vertical direction (TD) of 90°.

The copper alloy sheet material of the present embodiment is produced by a specific strong processing step without performing solution treatment, whereby the processed structure is precisely controlled and made high-strength, and is oriented from the rolling direction toward the rolling vertical direction. Significantly higher than conventional strengths are achieved in either of the 0°, 45° or 90° directions.

The Cu-(Ni, Co)-Si system used in the copper alloy sheet material of the present embodiment is a precipitation hardening type alloy, and is composed of an intermetallic compound such as a Ni-Si system, a Co-Si system, or a Ni-Co-Si system. The two phases are dispersed in the copper matrix phase in a fine size of about several nm, and high strength is obtained by precipitation hardening.

(tensile strength: TS)

The tensile strength of the copper alloy sheet material of the present embodiment in any one of 0°, 45°, and 90° from the rolling direction to the rolling vertical direction is 1020 MPa or more, preferably 1060 MPa or more. The upper limit of the tensile strength in any one of the rolling direction from 0°, 45°, and 90° in the rolling direction is 1400 MPa or less, preferably 1350 MPa or less. When the tensile strength is within the above range, the fatigue resistance is also excellent. If the tensile strength is too low, the fatigue resistance is inferior. On the other hand, if the tensile strength is too high, local elongation is less likely to occur. In addition, the tensile strength is a stress (unit: MPa) with respect to the maximum force applied in the tensile test according to JIS Z2241. According to the definition of σ _{TS in} Fig. 3, there is a case where the stress at the point where the slope of the stress-strain curve is zero (zero) is the tensile strength. On the other hand, in the present invention, it means that the stress immediately before the slope becomes zero is also set as the tensile strength.

(Electrical conductivity: EC)

In the copper alloy sheet material of the present embodiment, the electric conductivity is 20% IACS or more, preferably 23% IACS or more, and more preferably 26% IACS or more. If the conductivity is too high, there is a case where the strength is lowered, so the upper limit is 40% IACS or less.

In the present embodiment, the above-mentioned "% IACS" is a case where the resistivity of the International Annealed Copper Standard (International Annealed Copper Standard) is 1.7241 × 10 ^-8 Ωm is 100% IACS. Conductivity.

(Crystal orientation control)

The control of the crystal orientation distribution acts on the improvement of the tensile strength and the fatigue resistance in the 45° and 90° directions which are particularly remarkable in the present embodiment. As shown in the {100} pole diagram of X-rays, which is representatively shown in FIG. 4, it can be seen that the copper alloy sheet material of the present embodiment (Invention Example 205, FIG. 4(A)) can be obtained by a conventional manufacturing method ( Comparative Example 256, FIG. 4(B) or Comparative Example 257, FIG. 4(C)) A crystal orientation distribution not found in the middle, that is, a crystal structure which is not obtained conventionally.

(alloy composition)

‧Ni, Co, and Si form the elements of the second phase. These form the above intermetallic compound. It is necessary to add an element to this embodiment. The sum of the contents of any one or two of Ni and Co is 1.80 to 8.00% by mass, preferably 2.40 to 5.00% by mass, more preferably 3.20 to 5.00% by mass. Further, the content of Si is 0.40 to 2.00% by mass, preferably 0.50 to 1.20% by mass, more preferably 0.60 to 1.20% by mass. If the amount of such added elements is too small, the effect obtained is insufficient, the strength is insufficient, and the fatigue resistance is also inferior. On the other hand, if the amount of such necessary addition elements is too large, there is a case where the conductivity is lowered. Or there is a case where the material is broken during the rolling step. When Co is added, the conductivity is slightly improved. However, when the concentration of the element to be added is high in the state containing Co, the rolling fracture is likely to occur depending on the conditions of hot rolling and cold rolling. Thus, a more preferred embodiment of the invention is those in which the second phase does not contain Co.

‧Other elements

The copper alloy sheet material of the present embodiment may contain 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 above-mentioned essential addition element. Add elements arbitrarily. In the case where the optional additive element is contained, the total content of at least one element selected from the group consisting of Sn, Zn, Ag, Mn, P, Mg, Cr, Zr, Fe, and Ti is set to be 0.005 to 2.000 by mass. %. This optional additive element has an effect of promoting the refinement of the crystal grains and improving the strength characteristics and the fatigue resistance characteristics in the following intermediate cold rolling [Step 5] and final cold rolling [Step 7]. Moreover, it has an effect of improving the stress relaxation resistance, and is suitable for a case where the use environment is a high temperature such as 100 ° C or higher. However, if the content of any of the optional elements is excessive, there is a generation The case where the conductivity is lowered or the case where the material is broken during the rolling step is preferably 2.000% by mass or less.

‧Inevitable impurities

The unavoidable impurities in the copper alloy are contained in the ordinary elements of the copper alloy. Examples of the unavoidable impurities include O, H, S, Pb, As, Cd, and Sb. Regarding these, it is allowed to contain at most about 0.1% by mass as the total amount.

(Production method)

As a conventional method, in a method for producing a precipitation hardening type copper alloy material, a supersaturated solid solution state is formed by solution heat treatment, and then precipitated by aging treatment, and temper rolling is performed as needed ( Finish rolling) and quenching and tempering annealing (low temperature annealing, relaxation annealing). The manufacturing methods F, J, K, and L of the following comparative examples are equivalent to this.

On the other hand, in the present invention, a process different from the above-described conventional method becomes effective. For example, the process described below is effective. However, the present invention is not limited to the following methods.

An example of the method for producing a copper alloy sheet material according to the present embodiment is a method in which melting and casting are carried out [Step 1] to obtain an ingot, and the ingot is sequentially subjected to homogenization heat treatment [Step 2], hot working such as hot rolling. [Step 3], water cooling [Step 4], intermediate cold rolling [Step 5], heat treatment for aging precipitation [Step 6], final cold rolling [Step 7], and relaxation annealing [Step 8]. The relaxation annealing may also be omitted as long as the specific physical properties are obtained [Step 8].

In the present embodiment, the combination of the above-mentioned processes and the conditions of the intermediate cold rolling [Step 5] are set to a processing rate of 0 to 95%, and the conditions of the above aging treatment [Step 6] are set to 300 to 430 °C. This is achieved by limiting the combination of the specific conditions in the respective steps of the steps of the final cold rolling [step 7] of 60 to 99% for 5 minutes to 10 hours. The mechanism here is like Inferred as follows. By the action of the (Ni, Co)-Si compound precipitated in the above aging treatment [Step 6], the distribution state or crystal rotation of the difference row in the final cold rolling [Step 7] thereafter changes. Further, the separation of the crystal grains in the final cold rolling [Step 7] is induced by taking the rolling ratio of the final cold rolling [Step 7] higher.

The conditions for the preferable heat treatment and processing in each step are as follows.

The homogenization heat treatment [Step 2] is maintained at 900 to 1040 ° C for 1 hour or more, preferably for 5 to 10 hours.

Hot working such as hot rolling [Step 3] The temperature range from the start to the end of the hot working is 500 to 1040 ° C, and the processing rate is set to 10 to 90%.

Water cooling [Step 4] usually has a cooling rate of 1 to 200 ° C / sec.

The processing ratio of the intermediate cold rolling [Step 5] is set to 0 to 95%, preferably 71 to 95%.

The aging treatment [Step 6] is also referred to as aging precipitation treatment, and the conditions are maintained at 300 to 430 ° C for 5 minutes to 10 hours, and preferably the temperature range is 330 to 360 ° C.

The processing rate of the final cold rolling [Step 7] is 60 to 99%, preferably 60 to 89%.

The relaxation annealing [step 8] is maintained at 200 to 500 ° C for 5 seconds to 2 hours. If the holding time is too long, the strength is lowered. Therefore, it is preferable to set the annealing to a short time of 5 seconds or more and 5 minutes or less.

Here, the processing rate (or the reduction rate of the profile at the time of rolling) is a value defined by the following formula.

Processing rate (%) = {(t _{1 -} t ₂ ) / t ₁ } × 100

In the formula, t ₁ represents the thickness before the rolling process, and t ₂ represents the thickness after the rolling process.

Furthermore, after each heat treatment or rolling, depending on the state of oxidation or roughness of the surface of the material, the surface may be removed by surface cutting or pickling or surface grinding as needed. Oxide layer. Further, it may be corrected by a tension leveler depending on the shape and, if necessary. Further, when the roughness of the surface of the material is large due to the transfer of the unevenness of the rolling roll or the oil pit, the rolling speed, the rolling oil, the diameter of the rolling roll, and the rolling roll can be adjusted. The rolling conditions such as the surface roughness and the rolling reduction of one pass at the time of rolling.

(thickness)

The final thickness of the copper alloy sheet material of this embodiment after finish rolling is 30 μm to 1 mm. It is preferably 40 μm to 0.3 mm.

(physical property)

The copper alloy sheet material of the present embodiment preferably has the following physical properties.

(fatigue resistance)

In a preferred embodiment of the copper alloy sheet according to the present embodiment, in the fatigue test specified by JIS Z 2273, the vertical direction from the rolling direction to the rolling direction is 0°, 45°, or 90°. Excellent fatigue resistance in one direction. Specifically, when the test piece is repeatedly bent at a load stress of 500 MPa, the number of times until the breakage is preferably 4 × 10 ⁴ or more. This is the number of times that the system corresponds to 10 insertions per day in 10 years. More preferably, it is 8 × 10 ⁴ or more times, and further preferably 11 × 10 ⁴ times or more. Since the load stress in the 90° direction is particularly high depending on the design of the terminal, there is a case where particularly good fatigue resistance is required. As a more preferable aspect of the present invention, the life in the 90° direction is 2 × 10 ⁵ or more.

(local elongation)

In a preferred embodiment of the copper alloy sheet of the present invention, the local elongation is preferably from 0.03 to 10%, more preferably from 0.08 to 10%, still more preferably from 0.15 to 10%.

In the tensile test, if the maximum load (tensile strength σ _TS ) is exceeded, shrinkage (necking) occurs in one of the test pieces. The elongation after the shrinkage is produced is referred to as the local elongation. In Fig. 3, the stress-strain curve in the 0° direction of Inventive Example 205 is shown as a representative example. e _{U is} equivalent to uniform elongation, and e _{L is} equivalent to local elongation. In general, the more the strength of the material is increased, the more difficult it is to cause local elongation. The copper alloy sheet of the present invention preferably has high strength and a certain local elongation.

[Examples]

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

(Example 1)

An alloy ingot containing the alloy component elements described in Table 1 and having the remainder consisting of Cu and unavoidable impurities was melted in a high-frequency melting furnace and cast to obtain an ingot. Further, a test material for a copper alloy sheet according to the inventive example of the present invention and a comparative example thereof was produced by any of the following methods A, B, C, D, E and F. Further, in Table 1, which one of the methods A, B, C, D, E, and F is used is shown. The thickness of the final copper alloy sheet was set to 0.1 mm. In the case of the production methods J, K, and L described below, the final sheet thickness is also the same unless otherwise specified.

Incidentally, the numbers indicated in bold in the table mean that the content or the preparation method of the alloy component specified by the present invention is not satisfied, or the physical properties do not satisfy the range defined by the present invention or a preferred range.

(Method A)

The ingot is subjected to a homogenization heat treatment at 900 to 1040 ° C for 1 hour or more and 10 hours or less, and hot rolling is performed directly at the high temperature state. The end temperature of hot rolling is set to 500 ° C or more, and the processing rate is set to 10 to 90%. Water cooling is performed after the end of hot rolling. Thereafter, the table is taken as needed Face cutting. Thereafter, the intermediate cold rolling is performed in a processing ratio of 0 to 95%, the aging treatment is carried out at 300 to 430 ° C for 5 minutes to 10 hours, the processing rate is 60 to 99%, and the following relaxation force is performed. annealing.

(Method B)

Except for the above-described final cold rolling processing ratio of 99.1 to 99.9%, the same procedure as in the above-mentioned Process A was carried out.

(Method C)

The same procedure as in the above-mentioned Process A was carried out except that the processing rate of the final cold rolling was set to 30 to 59%.

(Method D)

The same procedure as in the above-mentioned Process A was carried out except that the heating temperature of the above aging treatment was 250 to 290 ° C and the processing rate of the final cold rolling was 60 to 89%.

(Method E)

The same procedure as in the above-mentioned Process A was carried out except that the heating temperature of the above aging treatment was 440 to 500 ° C and the processing rate of the final cold rolling was 60 to 89%.

(Method F)

After the intermediate cold rolling and before the aging treatment, the solution treatment is performed after the water quenching is performed at 700 to 1000 ° C for 5 seconds to 10 minutes, and the processing rate of the final cold rolling is set to 60 to 89%. Except for this, it carried out in the same manner as the above-mentioned Process A.

The conditions of the relaxation annealing in the above-mentioned processes A, B, C, D, E and F are maintained at 200 to 500 ° C for 5 seconds to 5 minutes.

Furthermore, after each heat treatment or rolling, depending on the state of oxidation or roughness of the surface of the material, The surface oxide layer is removed by surface cutting or pickling, or surface grinding as needed. Further, the correction by the tension leveling machine is performed according to the shape and as needed. Further, when the roughness of the surface of the material is large due to the transfer of the unevenness of the rolling roll or the oil sump, the rolling speed, the rolling oil, the diameter of the rolling roll, the surface roughness of the rolling roll, and the rolling are adjusted. The rolling conditions such as the rolling reduction of one pass at the time of manufacture.

Moreover, as another comparative example, the test material of the copper alloy sheet material was obtained by trial production by any of the following methods J, K, and L. The conditions of the manufacturing methods J, K, and L follow the conditions of the manufacturing methods described in the respective patent documents.

(Preparation method J) Patent Document 6: The method of Embodiment 2 of JP-A-2008-095186

The raw material of the copper alloy composition shown in the following Table 1 was melted by a high-frequency melting furnace, and cast into an ingot having a thickness of 30 mm, a width of 100 mm, and a length of 150 mm by a DC (direct casting) method, and the obtained ingot was obtained. After maintaining at a temperature of 1000 ° C for 1 hour, hot rolling was carried out to a thickness of 12 mm, and it was rapidly cooled. Then, the two sides of the hot-rolled sheet were cut by 1.5 mm to remove the oxide film, and then cold-rolled to a thickness of 0.15 to 0.1 mm, and then subjected to a solution treatment in a temperature range of 825 to 925 ° C for 15 seconds, immediately thereafter. It is cooled by a cooling rate of 10 ° C /sec or more. Then, aging treatment is performed at 420 to 480 ° C for 1 to 3 hours, and immediately thereafter, cooling is performed at a cooling rate of about 1 to 10 ° C / sec.

Then, cold rolling was performed at a rolling ratio of 30% or less to finally obtain a sheet having a thickness of 0.1 mm. Further, the conditions of the solution treatment and the aging heat treatment are appropriately selected depending on the alloy composition. After cold rolling, a 3 second relaxation annealing was performed at 650 °C.

(Production Method K) Patent Document 7: JP-A-2012-246549 Example 1, the method of the step A

The raw material of the copper alloy composition shown in the following Table 1 was melted by a high-frequency melting furnace and cast to obtain an ingot. In this state, the material for the supply was used, and the test material for the copper alloy sheet was produced by the following procedure. The thickness of the final alloy sheet was set to 0.12 mm.

The homogenization heat treatment is performed at a temperature of 950 to 1050 ° C for 3 minutes to 10 hours, and after heat rolling at 500 to 950 ° C, heat treatment is performed at 400 to 800 ° C for 5 seconds to 20 hours, and is performed for removing scale. Surface cutting. Thereafter, cold rolling 1 is performed at a processing rate of 90 to 99%, and intermediate annealing is performed at a temperature of 400 to 700 ° C for 5 seconds to 20 hours, and cold rolling is performed at a processing rate of 3 to 80%. Thereafter, the solution heat treatment is carried out at a temperature of 800 to 950 ° C for 5 seconds to 50 seconds, and the aging precipitation heat treatment is performed at a temperature of 350 to 600 ° C for 5 minutes to 20 hours, and 5 to 50% of the finish rolling is performed. And tempering annealing at a temperature of 300 to 700 ° C for 10 seconds to 20 hours.

(Production Method L) Patent Document 3: The method of Invention Example 1 described in Japanese Laid-Open Patent Publication No. 2006-152392

A copper alloy sheet was produced by casting a copper alloy having a copper alloy composition (Cu-6.0Ni-1.2Si-0.02P) shown in Table 1 below. In addition, as the other elements (unavoidable impurity elements) described above, the total amount of Al, Fe, Ti, Be, V, Nb, Mo, and W is 0.5% by mass or less. Further, the total amount of elements such as B, C, Na, S, Ca, As, Se, Cd, In, Sb, Pb, Bi, MM (rare earth metal alloy) is 0.1% by mass or less.

As a specific method for producing a copper alloy sheet, it is melted in a Kryptol furnace in the atmosphere under charcoal coating, and cast into a cast book book mold to obtain a thickness of 50 mm and a width. It is an ingot of 75 mm and a length of 180 mm. Further, after surface-cutting the surface of the ingot, hot rolling is performed at a temperature of 950 ° C until the thickness becomes 15 mm, and Quenching in water from a temperature above 750 °C. Then, after the scale was removed, cold rolling was performed to obtain a plate having a thickness of 0.75 mm.

Then, it was subjected to a solution treatment at a temperature of 900 ° C for 20 seconds using a salt bath furnace, and then quenched in water, and then cooled to a thickness of 0.6 mm by a cold rolling of a half of a processing rate of 20%. Extend the board. The cold-rolled sheet was aged for 4 hours at a temperature of 450 °C.

The properties of the test materials according to the inventive examples and comparative examples of the present invention were measured and evaluated in the following manner. The results are shown together in Table 1.

a. Tensile strength: TS

According to JIS, the test piece of JIS Z2201-13B which is cut from the rolling direction to the rolling vertical direction of 0° (rolling direction), 45° or 90° (rolling vertical direction) as shown in Fig. 2 is in accordance with JIS. Z2241 measures 3 in each direction and represents the average value. The tensile strength was set to the stress (in MPa) relative to the maximum force applied in the tensile test.

b. Conductivity: EC

The electrical conductivity was calculated by measuring the specific resistance by a four-terminal method in a constant temperature crucible maintained at 20 ° C (± 0.5 ° C) for each of the test materials. Furthermore, the distance between the terminals is set to 100 mm.

c. fatigue resistance

According to JIS, the test piece of JIS Z2201-13B which is cut from the rolling direction to the rolling vertical direction of 0° (rolling direction), 45° or 90° (rolling vertical direction) as shown in Fig. 2 is in accordance with JIS. Z 2273 measured the number of repetitions in each of the three directions in the case where the bending was repeated at a load stress of 500 MPa until the break, and the average value was respectively indicated.

d. Local elongation: e _L

As shown in Fig. 3, the local elongation (e _L ) was determined in the same tensile test as described above.

As shown in Table 1, all of the characteristics of any of Invention Examples 101 to 110 which satisfied the requirements of the present invention were excellent. In other words, in the examples 101 to 110, the higher the concentration of Ni/Co or Si is in the specific range, the direction from the rolling direction to the rolling vertical direction is 0°, 45° or 90°. Shows higher tensile strength [TS] and fatigue resistance (number of repetitions). Further, each of the inventive examples had a local elongation ratio except that the invention examples 104 and 106 were 0° or 90° from the rolling direction toward the rolling vertical direction.

On the other hand, in each of the comparative examples, since either of the alloy composition and the production conditions did not satisfy the conditions specified in the present invention, it was 0°, 45° or 90° in the vertical direction from the rolling direction toward the rolling direction. The tensile strength [TS] in any of the directions is low and does not satisfy the conditions specified in the present invention.

More specifically, in Comparative Example 151, since Ni/Co and Si were too small, the tensile strength [TS] was low in the direction from the rolling direction to the rolling vertical direction of 0° or 45°, which was not satisfactory. The conditions specified in the invention. Further, in Comparative Example 151, the fatigue resistance (number of repetitions) was inferior in the direction from the rolling direction to the rolling vertical direction of 0 or 45. In Comparative Example 152 in which the content of Ni and Si was too large, rolling fracture occurred and the manufacturability was inferior. In Comparative Examples 153 to 156 which were produced by the production method C, D, E or F, the production conditions did not satisfy the conditions specified in the present invention, and were in the direction of 0, 45 or 90 from the rolling direction toward the vertical direction of the rolling. The tensile strength [TS] is low in either direction and does not satisfy the conditions specified in the present invention. Further, in Comparative Examples 153 to 156, the fatigue resistance (the number of repetitions) was inferior in any of the 0°, 45°, or 90° directions from the rolling direction toward the rolling vertical direction.

As another comparative example, the manufacturing conditions of any of Comparative Example 157 using Process J and Comparative Example 158 using Process K did not satisfy the conditions specified in the present invention, and were 0 in the vertical direction from the rolling direction toward the rolling direction. Tensile strength in any of the °, 45° and 90° directions [TS] Both are low and do not satisfy the conditions stipulated by the present invention. Further, the fatigue resistance is inferior in any of the 0°, 45°, and 90° directions from the rolling direction toward the rolling vertical direction.

(Example 2)

Using the same production method, test, and measurement method as in Example 1, copper alloy sheets were produced using various copper alloys shown in Table 2, and the characteristics thereof were evaluated. The results are shown in Table 2.

As shown in Table 2, all of the characteristics of any of the invention examples 201 to 210 which satisfy the requirements of the present invention are excellent. According to the effect of adding any of the added elements, although not in all of the test examples, it is considered that there is a tendency to be one of the 0°, 45°, or 90° directions from the rolling direction toward the rolling vertical direction. The higher tensile strength [TS] and fatigue resistance (number of repetitions) are increased. Further, each of the inventive examples had a local elongation ratio except for the invention examples 203 and 206, which were 0° or 90° from the rolling direction toward the rolling vertical direction.

On the other hand, in each of the comparative examples, since either of the alloy composition and the production conditions did not satisfy the conditions specified in the present invention, it was 0°, 45° or 90° in the vertical direction from the rolling direction toward the rolling direction. The tensile strength [TS] in any of the directions is low and does not satisfy the conditions specified in the present invention.

More specifically, in Comparative Example 251 in which the sub-addition element (Sn in this example) is excessive, rolling fracture occurs, and the manufacturability is inferior. In Comparative Examples 252 to 255 using Process C, D, E or F, the manufacturing conditions did not conform to the conditions specified in the present invention, and were 0°, 45° or 90° in the vertical direction from the rolling direction toward the rolling direction. The tensile strength [TS] is low in either direction and does not satisfy the conditions specified in the present invention. Further, in Comparative Examples 252 to 255, the fatigue resistance was poor in any of the 0°, 45°, or 90° directions from the rolling direction toward the rolling vertical direction.

As another comparative example, the manufacturing conditions of any of Comparative Example 256 using Process J, Comparative Example 257 using Process K, and Comparative Example 258 using Process L were not in accordance with the conditions stipulated by the present invention. The tensile strength [TS] in either of the 0°, 45°, and 90° directions in the direction perpendicular to the rolling direction is low, and the conditions specified by the present invention are not satisfied. Further, the fatigue resistance is inferior in any of the 0°, 45°, and 90° directions from the rolling direction toward the rolling vertical direction.

[Industrial availability]

The copper alloy sheet of the present invention can be preferably used for any type of connector. In particular, in addition to the external connector represented by the dock connector or the USB connector, it can be preferably used as a thin plate spring material for a camera module or a movable piece for a relay.

The present invention has been described with reference to the embodiments of the present invention. However, it is not intended to limit the invention in any detail. The spirit and scope of the illustrated invention is broadly explained before.

Claims (6)

A copper alloy sheet material having a composition comprising: 1 or 2 of Ni and Co in total, 1.80 to 8.00% by mass, Si of 0.40 to 2.00% by mass, and a total of 0.000 to 2.000% by mass selected from the group consisting of At least one element selected from the group consisting of Sn, Zn, Ag, Mn, P, Mg, Cr, Zr, Fe, and Ti, the remainder being composed of copper and unavoidable impurities; and conductivity of 20 to 40% IACS or more The tensile strength in the direction from the rolling direction (RD) to the rolling vertical direction (TD) of 0°, 45°, and 90° is 1020 to 1400 MPa. The copper alloy sheet according to claim 1 which contains at least 0.005 to 2.000 mass% of at least a group selected from the group consisting of Sn, Zn, Ag, Mn, P, Mg, Cr, Zr, Fe, and Ti. 1 element. A connector comprising a copper alloy sheet material of claim 1 or 2. A method for producing a copper alloy sheet, which is carried out in the following steps: a melting and casting step of melting and casting a copper alloy raw material to obtain a copper alloy containing a total of 1.80 to 8.00% by mass of Ni and Co Any one or two of them, 0.40 to 2.00% by mass of Si, and a total of 0.000 to 2.000% by mass selected from the group consisting of Sn, Zn, Ag, Mn, P, Mg, Cr, Zr, Fe, and Ti. At least one element in the group, the remainder consisting of copper and unavoidable impurities; a homogenization heat treatment step of heat treatment at 900 to 1040 ° C for more than 1 hour; a thermal processing step from the beginning to the end of the thermal processing The temperature range is 500~1040 °C, the processing rate is 10~90%; the intermediate cold rolling step, the processing rate is 0~95%; The heat treatment step is performed at 300 to 430 ° C for 5 minutes to 10 hours; and the final cold rolling step, the processing rate is 60 to 99%. The method for producing a copper alloy sheet according to the fourth aspect of the invention, wherein the copper alloy raw material for the melting and casting step contains 0.005 to 2.000 mass% in total selected from the group consisting of Sn, Zn, Ag, Mn, P, and Mg. At least one element selected from the group consisting of Cr, Zr, Fe, and Ti. The method for producing a copper alloy sheet according to claim 4, wherein after the final cold rolling step, the relaxation annealing is performed at 200 to 500 ° C for 5 seconds to 2 hours.