JP5017719B2 - Copper-based alloy plate excellent in press workability and method for producing the same - Google Patents

Description

TECHNICAL FIELD The present invention relates to a copper-based alloy plate excellent in press workability and a method for manufacturing the same, and more particularly to consumer products such as semiconductor lead frame master plates, information / communication narrow pitch connector master plates, and small relay master plates. The present invention relates to a copper-based alloy plate excellent in press workability and a method for producing the same.

With the high-density mounting of home appliances, information communication devices, and automotive parts, connectors, switches, relays, and the like have been miniaturized, and the materials constituting them tend to be thinner and thinner.
These parts are usually stamped by a high-speed press using a mold, and during the press processing, the material undergoes shear deformation by the punch of the mold, and then, by the occurrence of cracks from the blade edge, Breaking deformation is generated and punched into a predetermined shape.

  However, as the number of press shots increases, wear of the die punch blade edge progresses. As a result, crack generation from the blade edge becomes uneven, the fracture shape is disturbed, specifically, the shear band and fracture. The step of the band becomes large, large burrs are generated, and large waste of material generated by fracture is generated, so that a predetermined product shape cannot be maintained.

  Conventionally, as countermeasures to improve the mold life, we have responded by improving the punch material, improving the lubricity by press lubricant, and setting the clearance suitable for each copper base alloy, but it is a breakthrough improvement Could not be realized.

As a result of diligent studies to solve the problems of the prior art as described above, materials such as small connectors, switches, and relays that are punched into a predetermined shape by high-speed press molding using a die are used. In particular, it was found that excellent press workability is an important characteristic problem to be solved.
That is, it has been found that a copper-based alloy plate excellent in press workability can be obtained by controlling the crystal orientation of the material, and therefore the present invention proposes the alloy plate and its manufacturing method.

The present invention relates to a copper or copper-based alloy material, in particular, the RD surface (cross section perpendicular to the rolling direction of the plate material; hereinafter referred to as the RD surface) and the TD surface (cross section parallel to the rolling direction of the plate material; hereinafter referred to as TD). A copper-based alloy plate having improved press workability by performing X-ray diffraction focusing on the surface and controlling the strength in a specific direction among the obtained crystal orientations, and a method for producing the same It is. Here, the X-ray diffraction intensity indicates, for example, the integrated intensity of the crystal orientation of the material measured by the X-ray diffraction method.
That is, the present invention

ここで、Ｓ_ＲＤは材料の加工方向に垂直な断面のＸ線回折強度について、Ｓ_ＴＤは材料の加工方向に平行な断面のＸ線回折強度について測定した値で、Ｉ｛１１１｝は｛１１１｝の回折強度、Ｉ｛２２２｝は｛２２２｝の回折強度、Ｉ｛２００｝は｛２００｝の回折強度である。 1.0 to 21.1 mass% of Zn, and further, one or more selected from Sn, Ni, Si, Fe, and Al are included in a total amount of 4 to 25 mass %, with the remainder being Cu and inevitable S _RD ≧ 2 in the X-ray diffraction intensity of the cross section perpendicular to the processing direction of the material, and S _TD ≧ 4 in the X-ray diffraction intensity of the cross section parallel to the processing direction of the material. A copper-based alloy plate excellent in press workability, wherein S _RD × S _TD ≧ 16.
However,

Here, S _RD is a value measured for the X-ray diffraction intensity of a cross section perpendicular to the processing direction of the material, S _TD is a value measured for an X-ray diffraction intensity of a cross section parallel to the processing direction of the material, and I {111} is {111} }, I {222} is the diffraction intensity of {222}, and I {200} is the diffraction intensity of {200}.

ここで、Ｓ_ＲＤは材料の加工方向に垂直な断面のＸ線回折強度について、Ｓ_ＴＤは材料の加工方向に平行な断面のＸ線回折強度について測定した値で、Ｉ｛１１１｝は｛１１１｝の回折強度、Ｉ｛２２２｝は｛２２２｝の回折強度、Ｉ｛２００｝は｛２００｝の回折強度である。 2. 1.0 to 21.1 mass% of Zn and further one or more selected from Sn, Ni, Si, Fe, and Al are included in a total amount of 4 to 25 mass% , with the remainder being Cu and inevitable specifically an ingot of a copper-based alloy consisting of impurities, heat treated materials were to a predetermined thickness by cold rolling at a rolling rate of 50% or more at a temperature of 350 to 750 ° C., in the working direction of the material The X-ray diffraction intensity of the vertical cross section is 1 ≦ S _RD ≦ 3 and the X-ray diffraction intensity of the cross section parallel to the processing direction of the material is 1 ≦ S _TD ≦ 3. By combining hot rolling and low temperature annealing below the recrystallization temperature, S _RD ≧ 2 in the X-ray diffraction intensity of the cross section perpendicular to the processing direction of the material and S in the X-ray diffraction intensity of the cross section parallel to the processing direction of the material. _TD ≧ _{4, S RD} × _S Method for producing a copper base alloy sheet having excellent press formability, characterized in that the _D ≧ 16.
However,

Here, S _RD is a value measured for the X-ray diffraction intensity of a cross section perpendicular to the processing direction of the material, S _TD is a value measured for an X-ray diffraction intensity of a cross section parallel to the processing direction of the material, and I {111} is {111} }, I {222} is the diffraction intensity of {222}, and I {200} is the diffraction intensity of {200}.

The contents of the present invention will be specifically described below.
The present invention performs X-ray diffraction on a copper-based alloy sheet , focusing particularly on a cross section perpendicular to the processing direction of the material and controlling the strength of a specific orientation among the obtained crystal orientations. It improves workability.

  First of all, it is important to align the crystal orientation to a certain orientation in order to make the crack generation from the blade uniform when the material undergoes shear deformation during press working. The shape of the press cross section is better when aligned with {111}. On the other hand, if there are many other surfaces, especially {200} planes in the cross section, the extension direction of cracks generated when shear deformation occurs is at an angle of 20 ° or more with respect to the direction of the press. The wear of the blade edge is promoted, and a large residue of material generated by the breakage adheres to the blade edge to promote the wear of the blade edge. Therefore, the smaller the {200} plane, the better the cross-sectional shape of the press, and the wear of the cutting edge can be suppressed.

なるパラメーターＳを導入し、ＲＤ面について測定したＳをＳ_ＲＤ、ＴＤ面について測定したＳをＳ_ＴＤとすると、Ｓ_ＲＤ≧２ かつＳ_ＴＤ≧４で、かつＳ_ＲＤ×Ｓ_ＴＤ≧１６のときは、プレスで打抜いた端子の形状が良好であった。 A cross section perpendicular to the processing direction of the material is expressed as an RD plane, and a parallel cross section is expressed as a TD plane. X-ray diffraction of the RD plane and the TD plane is performed, and {111} diffraction intensity I {111}, {222} diffraction intensity I {222}, {200} diffraction intensity I {200} are measured,

When the parameter S is introduced, S measured for the RD plane is S _RD , and S measured for the TD plane is S _TD , when S _RD ≧ 2 and S _TD ≧ 4, and S _RD × S _TD ≧ 16 The shape of the terminal punched with a press was good.

on the other hand,
When S _RD ≧ 2 and S _TD ≧ 4 and S _RD × S _TD <16,
When S _RD ≧ 2 and S _TD <4 and S _RD × S _TD <16,
When S _RD ≧ 2 and S _TD <4 and S _RD × S _TD ≧ 16,
When S _RD <2 and S _TD ≧ 4 and S _RD × S _TD <16,
When S _RD <2 and S _TD ≧ 4 and S _RD × S _TD ≧ 16,
When S _RD <2 and S _TD <4 and S _RD × S _TD <16,
As the number of press shots increased, wear of the blade edge advanced, and the shape of the punched terminal deteriorated.

  The material of the present invention can be manufactured through the following steps. That is, the first step is a step in which a predetermined amount of each component is blended and dissolved, and an ingot having a predetermined composition is cast from the obtained liquid. This step can be applied by a melting method in the air, a melting method in a reducing atmosphere, or a vacuum melting method.

  The second step is a step of heat-treating the obtained ingot, and this step is a step of reducing the segregation generated during casting by heat-treating at a temperature of 700 ° C. or higher, and uniformizing the crystal orientation of the material. This is an important process.

  The third step is a rough rolling step, and the rolling rate is preferably 50% or more. This step is an important step for recrystallization in the next fifth step. When the rolling rate is less than 50%, the recrystallized grains become non-uniform, and as a result, the crystal orientation is non-uniform. In the subsequent process, it becomes difficult to orient the crystal orientation of the material cross section to {111}. This process can be applied to both cold rolling and warm rolling.

The fourth step is a heat treatment step in which the crystal grain size of the material is made uniform and fine, and in order to orient the crystal orientation of the cross section of the material to {111} in the fifth step and thereafter, it is once in a non-oriented state. This is a process for fading. The heat treatment temperature is 350 to 750 ° C. When the temperature is less than 350 ° C., the above heat treatment effect cannot be sufficiently exhibited. When the temperature exceeds 750 ° C., the crystal grain size becomes coarse, and a desired press can be obtained regardless of how the subsequent steps are devised. Workability cannot be obtained. In particular, it is preferable that 1 ≦ S _RD ≦ 3 and 1 ≦ S _TD ≦ 3.

  The fifth step is a final cold rolling step, and the sixth step is a low temperature annealing step. What is important in the fifth step is that the rolling rate is 30% or more. In this step, the degree of aggregation of the crystal orientation {111} of the material cross section is increased, and the degree of aggregation of the crystal orientation {200} of the material cross section is suppressed. When the rolling processing rate is less than 30%, since the processing strain to be input is small, it is difficult to orient the crystal orientation of the material cross section to {111}. Preferably it is 50% or more, more preferably 80% or more.

The sixth step is a step of removing excessive processing strain generated in the fifth step by heat treatment, and can improve the bending workability of the material. The heat treatment temperature in this step is less than the recrystallization temperature of each material, preferably the heat treatment temperature is 200 to 400 ° C.
Examples of the copper-based alloy according to the present invention include a copper-based alloy such as a Cu—Zn—Sn—Ni—Si alloy, a Cu—Zn—Ni—Fe—Al alloy, and a Cu—Zn—Sn—Fe alloy. Is mentioned.

The component range of the copper-based alloy according to the present invention is 4 to 4 in total of 1.0 to 21.1 mass% of Zn and one or more selected from Sn, Ni, Si, Fe, and Al. It is defined that it contains ˜25 mass% , and is composed of the balance Cu and inevitable impurities, in order to maintain the balance of electrical conductivity, tensile strength, spring limit value and bending workability of the material, and to improve press workability. It is.

If the total amount of Zn and one or more selected from Sn, Ni, Si, Fe, and Al is less than 4 mass% , the electrical conductivity increases, but the tensile strength, spring limit value, and press workability are increased. It is difficult to obtain characteristics such as heat resistance. Further, when the rolling process rate is increased to improve the tensile strength, spring limit value, and press workability, the bending workability deteriorates. On the other hand, when the total amount of Zn and one or more selected from Sn, Ni, Si, Fe, and Al exceeds 25 mass% , the tensile strength and the spring limit value increase, The rate is lowered, and the bending workability is further deteriorated.

Accordingly, the content range of copper-based alloy according to the present invention, Sn, Ni, Si, Fe, comprise 4 to 25 mass% in total and one or more selected from among Al, balance Cu and unavoidable It was defined as a copper-based alloy composed of impurities. It should be noted that elements other than the additive elements defined in the present invention, for example, Ag, Au, Bi, Co, Cr, In, Mn, La, Pd, Pb, Sb, Se, Te, Ti, Y, Zr If the total amount of one or more selected from the above is 5 mass% or less, the effect obtained is not inhibited even when added to the additive element defined in the present invention.

  Next, embodiments of the present invention will be described by way of examples.

  As described above, according to the present invention, it is possible to obtain copper-based alloys for connectors, switches, relays, etc. that are excellent in press workability, and high-density mounting of recent home appliances, information communication devices, and automotive parts. The cost can be greatly reduced by making the material thinner and thinner, and improving the press die life.

Examples Copper base alloys Nos. 1 to 16 whose chemical component values (mass%) are shown in Table 1 were melted in an Ar atmosphere using a high-frequency melting furnace and cast into 40 × 40 × 150 (mm) ingots. A test piece of 10 ^t × 40 ^w × 40 ^l (mm) was cut out from the obtained ingots of No. 1 to 16, and homogenized heat treatment was performed at 850 ° C. for 1 h (second step). 3, Nos. 9 and 10 are rolled from 10 mm to 2.0 mm by cold rolling, and Nos. 4 to 8 and Nos. 11 to 16 are rolled from 10 mm to 5 mm by hot rolling. The sheet thickness was rolled from 5 mm to 2.0 mm by hot rolling (third step).

Next, among No. 1 to 16 obtained test pieces, No. 1 to 11 and No. 13 were subjected to heat treatment at 500 ° C. × 1 h, and No. 12 and No. 14 to 16 were A heat treatment at 600 ° C. × 1 h was performed (fourth step). X-ray diffraction was performed on the RD surface and TD surface of the obtained test piece, and _SRD and _STD were measured.
The measurement conditions for the X-ray diffraction intensity are as follows.
Tube: Cu, tube voltage: 40 KV, tube current: 30 mA, sampling width: 0.002 ° using chromometer, sample holder: AL
As a result, No. 1 to 11 and No. 13 satisfied 1 ≦ S _RD ≦ 3 and 1 ≦ S _TD ≦ 3 , while No. 12 and No. 14 to 16 were 1 ≦ S _RD ≦ 3 , 1 ≦ S _TD ≦ 3 was not satisfied.
Note that the X-ray diffraction measurement conditions are not limited to the above conditions, and are appropriately changed according to the type of the sample.

  For No. 1 to 16 obtained in this way, cold rolling (fifth step) was performed, and for No. 1 to 8 and No. 12, the rolling rate after heat treatment (fourth step) was 30. % No. 9 to 11 and No. 13 to 16 were rolled so that the rolling rate after heat treatment (fourth step) was less than 30%, and 0.20 mm Finished to plate thickness.

Finally, a heat treatment (sixth step) at 300 ° C. × 1 h was performed to obtain a sample for evaluation.
S _RD , S _TD , and S _RD × S _TD were measured for the samples thus obtained. Furthermore, the terminal-shaped continuous press processing was implemented about these samples, the press processing was stopped when the burr | flash height of material exceeded 25 micrometers, and the number of shots so far was made into the maximum number of shots.

From the results in Table 1, the following is clear.
The alloys of Nos. 5, 7, and 8 according to the present invention satisfy S _RD ≧ 2, S _TD ≧ 4, and S _RD × S _TD ≧ 16, and the maximum number of press shots exceeds 2 million shots. It is a copper-based alloy material with excellent press workability.

On the other hand, No. 12 which does not satisfy 1 ≦ S _RD ≦ 3 and 1 ≦ S _TD ≦ 3 does not satisfy S _TD ≧ 2 and S _RD × S _TD ≧ 16 in the fourth step, and 1.5 million Beyond the shot, the burr on the RD surface was 30 μm. Of No. 9 to 11 and No. 13 in which the rolling process rate is less than 30% in the fifth step, No. 9 and 10 do not satisfy S _TD ≧ 4 and S _RD × S _TD ≧ 16. When the maximum number of shots is exceeded, the burr on the TD surface exceeds 25 μm, and Nos. 11 and 13 do not satisfy all of S _RD ≧ 2, S _TD ≧ 4, S _RD × S _TD ≧ 16, Before reaching 1 million shots, the burr on the RD and TD surfaces exceeded 25 μm.

Among the Nos. 14 to 16 that do not satisfy 1 ≦ S _RD ≦ 3 and 1 ≦ S _RD ≦ 3 in the fourth step, and the rolling process rate is less than 30% in the fifth step, No. 14 And 15 did not satisfy S _TD ≧ 2 and S _RD × S _TD ≧ 16. When 1 million shots were reached, the burr on the RD surface exceeded 25 μm. No. 16 does not satisfy S _TD ≧ 4, the burr on the TD surface exceeds 25 μm in about 1 million shots, and the residue of the material adheres between the punch and the die, and the press continues. Is no longer possible.

Reference Example Alloy No. 4 shown in Table 1 above and a commercially available phosphor bronze alloy (C5191 grade H: 6.5 mass% Sn, 0.2 mass% P, balance Cu) and copper base alloy (C7025 grade H: 3.2 mass) % NI, 0.70 mass% SI, 0.15 mass% Mg, balance Cu) were evaluated for Vickers hardness, tensile strength, spring limit value, conductivity, press workability and bending workability.

  The measurements of Vickers hardness, tensile strength, spring limit value, and conductivity were performed according to JIS Z2244, JIS Z2241, JIS H3130, and JIS H0505, respectively. The press workability was evaluated by measuring the maximum number of press shots in the same manner as in Example 1. The bending workability is 90 ° W bending test (conforming to JIS H 3110), the inner bending radius R is 0.08 mm, the ratio R / t of the bending radius R and the plate thickness t is 0.4, and the convex surface at the center is Evaluation was made with good marks as ◯, wrinkled marks as △ marks, and cracks as x marks. The results are shown in Table 2.

  From Table 2, the copper base alloy of No. 4 is Vickers hardness, tensile strength, spring limit value, electrical conductivity, compared with conventional copper base alloys C5191 and C7025 for typical connectors, switches and relays. It turns out that it is excellent in the balance of rate, press workability, and bending workability.

As described above, the present invention has obtained copper or a copper-based alloy for connectors, switches, and relays excellent in press workability, and has achieved high-density mounting of recent home appliances, information communication equipment, and automotive parts. Accordingly, the present invention provides a copper-based alloy plate that can realize a significant cost reduction by thinning and thinning the material and improving the press die life.

Claims (3)

It contains 1.0 to 21.1 mass% of Zn and 4 to 25 mass% in total of one or more selected from Sn, Ni, Si, Fe, and Al, with the remainder being Cu and inevitable impurities S _RD ≧ 2 in the X-ray diffraction intensity of the cross section perpendicular to the processing direction of the material, and S _TD ≧ 4 , S _RD × S in the X-ray diffraction intensity of the cross section parallel to the processing direction of the material. A copper-based alloy plate excellent in press workability, wherein _TD ≧ 16.
However,

Here, S _RD is a value measured for the X-ray diffraction intensity of a cross section perpendicular to the processing direction of the material, S _TD is a value measured for an X-ray diffraction intensity of a cross section parallel to the processing direction of the material, and I {111} is {111} }, I {222} is the diffraction intensity of {222}, and I {200} is the diffraction intensity of {200}. It contains 1.0 to 21.1 mass% of Zn and 4 to 25 mass% in total of one or more selected from Sn, Ni, Si, Fe, and Al, with the remainder being Cu and inevitable impurities the ingot of the copper base alloy consisting of, heat treated materials were to a predetermined thickness by cold rolling at a rolling rate of 50% or more at a temperature of 350-750 ° C., perpendicular to the working direction of the material Final cold rolling with 1 ≦ S _RD ≦ 3 in the X-ray diffraction intensity of the cross section and 1 ≦ S _TD ≦ 3 in the X-ray diffraction intensity of the cross section parallel to the processing direction of the material. And low temperature annealing below the recrystallization temperature, S _RD ≧ 2 in the X-ray diffraction intensity of the cross section perpendicular to the processing direction of the material and S _TD ≧ in the X-ray diffraction intensity of the cross section parallel to the processing direction of the material. 4, S _RD × S _TD Method for producing a copper base alloy sheet having excellent press formability, characterized in that a ≧ 16.
However,

Here, S _RD is a value measured for the X-ray diffraction intensity of a cross section perpendicular to the processing direction of the material, S _TD is a value measured for an X-ray diffraction intensity of a cross section parallel to the processing direction of the material, and I {111} is {111} }, I {222} is the diffraction intensity of {222}, and I {200} is the diffraction intensity of {200}. The manufacturing method of the copper base alloy plate excellent in press workability of Claim 2 which makes the rolling rate of the said last cold rolling 50% or more.