JPH10195562A - Copper alloy for electrical and electronic equipment, excellent in blanking workability, and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a copper alloy excellent in blanking workability capable of sufficiently meeting the recent damand for making electrical and electronic equipment part highly integrated, compact, low-cost, etc., by incorporating specific amount of at least one element among Pb, Bi, Ca, Sr, Ba, and Te into Cu or a Cu alloy containing Cu and Zn, Zr, Sn, Ni, P, Fe, Cr, etc. SOLUTION: One or more elements among Pb, Bi, Ca, Sr, Ba, and Te are incorporated by 0.002-0.5wt.% into Cu or a Cu alloy. If necessary, 0.01-0.5% of one or more elements among Sn, Cr, Mg, Zr, Ni, Ag, and Mn and further incorporated. As the Cu alloy, alloys of Cu-Zn, Cu-Zr, Cu-Sn, Cu-Sn-Ni, Cu-Sn-Ni- P, Cu-Fe, Cu-Fe-P, Cu-Fe-Zn-P, Cu-Cr, Cu-Cr-Zr, etc., are suitably used. It is preferable to regulate the size of crystallized substances or precipitates and the size of crystalline grains to <=5μm and <30μm, respectively, by controlling working conditions for the Cu alloy of the above composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a terminal material, a connector material, and a switch material for electrical and electronic equipment to be subjected to a punching process.
The present invention relates to a copper alloy for electrical and electronic equipment suitable for a lead frame material of a semiconductor such as an IC, particularly a contact material, a wiring / distribution material, a heat sink (heat spreader) material, an electrode material, and a method of manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, materials for electric and electronic devices such as lead frame materials, terminal materials, and distribution devices of semiconductor devices include strength, heat resistance, electric conductivity, heat conductivity, springability, bending workability, and the like. In addition, since plating with a noble metal such as Ag or Pd, or plating with Sn or solder is performed, plating properties, solder bonding properties, surface smoothness, and the like are also required. Materials satisfying these characteristics include Cu-Sn, Cu-Zn, Cu
-Sn-Ni, Cu-Ni, Cu-Ni-Zn, etc.
u-Zr, Cu-Fe, Cu-Co, Cu-Cr, Cu-Ti, C
u-Be, Cu-Ni-Ti, Cu-Fe-Ti, Cu-Cr-Zr, Cu-Ni-
Si-based, Cu-Ni-Sn-based precipitation-type copper alloys, more oxygen-free copper,
Pure copper alloys such as tough pitch copper and Ag-containing copper are available.
The copper alloy is properly used depending on the application, for example, a transistor or an insertion type lead frame material having a small number of pins includes a Cu-Fe-based alloy and a Cu-Zr-based alloy having good heat resistance and electric conductivity. High-strength, excellent electrical conductivity, and excellent Cu-Sn-Ni and Cu-Cr alloys for plating and soldering And Cu-Cr-Zr alloys are widely used. For terminal and connector materials, Cu-Zn alloy with good cost and good workability, excellent in strength and spring property etc.
Cu-Sn alloys and the like are used.

[0003] As a method of forming the copper alloy into a lead frame or a terminal, a punching method is mainly used, and the copper alloy is required to have high punching workability in order to secure dimensional accuracy. This demand has become more and more severe with recent high integration, miniaturization, high performance, and low cost of electric and electronic devices such as semiconductor devices. In other words, a thin lead frame with a large number of pins and a fine pitch, or a small lead frame in the form of a matrix in which pins are formed in multiple rows requires particularly high dimensional accuracy, but these are also formed by a punching method. Have been. In addition, for terminals, connectors, and power distribution members, there has been a demand for improved punching workability for the purpose of reducing mold wear and maintenance frequency.

[0004]

However, when a conventional copper alloy is stamped into a part, there are the following problems. (1) Punching burrs and powder remain on the surface of the part to cause dent scratches on the part and damage the mold. (2) Excessive processing strain occurs on the part, reducing dimensional accuracy. 3) Die wear is severe and life is short. (4) For microfabricated parts such as lead frames and small terminals, shorts occur between leads due to punch burrs. For this reason, the present inventors have conducted intensive studies for the purpose of improving the punching workability, and have found that the above problem can be improved by adding an appropriate amount of an element dispersed as a compound in a copper matrix, and further research has been conducted. Thus, the present invention has been completed. SUMMARY OF THE INVENTION An object of the present invention is to provide a copper alloy for electrical and electronic equipment excellent in punching workability, which is suitable as a material for electrical and electronic equipment such as a lead frame, a terminal, and a connector, and a method of manufacturing the same.

[0005]

According to the first aspect of the present invention,
A copper alloy for electrical and electronic equipment having excellent punching characteristics, characterized in that Cu contains at least one element of Pb, Bi, Ca, Sr, Ba and Te in an amount of 0.002 to 0.5 wt%. .

The invention according to claim 2 is characterized in that at least one of the elements Pb, Bi, Ca, Sr, Ba, and Te is contained in the Cu-Zn alloy at 0.002 to 0.5 wt%. It is a copper alloy for electrical and electronic equipment with excellent punching workability.

According to a third aspect of the present invention, Zr is set to 0.02 to 0.2 w.
Pb, Bi, Ca, S in Cu-Zr alloy containing t%
at least one of the elements r, Ba and Te is 0.002
It is a copper alloy for electrical and electronic equipment excellent in punching work, characterized by containing 0.5 wt%.

The invention according to claim 4 is characterized in that at least one of the elements Pb, Bi, Ca, Sr, Ba and Te is contained in the Cu-Sn-based alloy in an amount of 0.002 to 0.5 wt%. It is a copper alloy for electrical and electronic equipment with excellent punching workability.

According to a fifth aspect of the present invention, there is provided Cu-Sn-Ni
A copper alloy for electrical and electronic equipment with excellent punching characteristics, characterized in that at least one of the elements Pb, Bi, Ca, Sr, Ba, and Te is contained in the base alloy. is there.

[0010] The invention according to claim 6 is that Sn is 1.5 to 2.5 watts.
C containing 0.1% to 0.3% by weight of Ni and 0.15% by weight of P
Pb, Bi, Ca, Sr, u-Sn-Ni-P alloy
At least one of the elements Ba and Te is 0.002-0.
It is a copper alloy for electrical and electronic equipment with excellent punching characteristics characterized by containing 5 wt%.

The invention according to claim 7 is characterized in that at least one of the elements Pb, Bi, Ca, Sr, Ba and Te is contained in the Cu-Fe alloy at 0.002 to 0.5 wt%. It is a copper alloy for electrical and electronic equipment with excellent punching workability.

The invention according to claim 8 is characterized in that Fe is contained in an amount of 0.02 to 0.5 w
t%, at least one element of Pb, Bi, Ca, Sr, Ba, and Te is contained in a Cu-Fe-P-based alloy containing 0.01 to 0.2 wt% of P in an amount of 0.002 to 0.5 wt%. It is a copper alloy for electrical and electronic equipment with excellent punching characteristics.

According to a ninth aspect of the present invention, the amount of Fe is 1.0 to 2.6 watts.
Pb, Bi, Ca, S in Cu-Fe-Zn-P-based alloy containing 0.05% to 2.0% by weight of Zn, 0.05% to 2.0% by weight of Zn, and 0.015% to 0.15% by weight of P.
at least one of the elements r, Ba and Te is 0.002
It is a copper alloy for electrical and electronic equipment excellent in punching work, characterized by containing 0.5 wt%.

The invention according to claim 10 is characterized in that at least one of the elements Pb, Bi, Ca, Sr, Ba and Te is contained in the Cu-Cr-based alloy at 0.002 to 0.5 wt%. It is a copper alloy for electrical and electronic equipment with excellent punching workability.

[0015] The invention according to claim 11 is a method for producing Cu—Cr—Zr
A copper alloy for electrical and electronic equipment with excellent punching characteristics, characterized in that at least one of the elements Pb, Bi, Ca, Sr, Ba, and Te is contained in the base alloy. is there.

The invention described in claim 12 is the first or second invention.
The copper alloy for electrical and electronic equipment according to any one of 7, 8, and 9, further comprising Sn, Cr, Mg, Zr, Ni, Ag, and Mn.
A copper alloy for electrical and electronic equipment having excellent punching properties, characterized by containing at least one of the elements of 0.01 to 0.5 wt% in total.

According to a thirteenth aspect of the present invention, there is provided a copper alloy for electrical and electronic equipment according to the third aspect, further comprising Sn, Cr, Mg, N
at least one of the elements i, Ag and Mn in total
It is a copper alloy for electrical and electronic equipment excellent in punching work, characterized by containing 0.01 to 0.5 wt%.

According to a fourteenth aspect of the present invention, the copper alloy for electrical and electronic equipment according to the fourth aspect further comprises Cr, Mg, Zr, N
at least one of the elements i, Ag and Mn in total
It is a copper alloy for electrical and electronic equipment excellent in punching work, characterized by containing 0.01 to 0.5 wt%.

According to a fifteenth aspect of the present invention, there is provided a copper alloy for electrical and electronic equipment according to any one of the fifth and sixth aspects, further comprising Cr,
A copper alloy for electrical and electronic equipment having excellent punching characteristics, characterized by containing at least one of Mg, Zr, Ag, and Mn elements in a total amount of 0.01 to 0.5 wt%.

According to a sixteenth aspect of the present invention, there is provided a copper alloy for electrical and electronic equipment according to the tenth aspect, further comprising Sn, Mg, Zr, N
at least one of the elements i, Ag and Mn in total
It is a copper alloy for electrical and electronic equipment excellent in punching work, characterized by containing 0.01 to 0.5 wt%.

According to a seventeenth aspect of the present invention, there is provided a copper alloy for electric and electronic equipment according to the eleventh aspect, wherein Sn, Mg, Ni, A
g, at least one of the elements of Mn in total of 0.01 to
It is a copper alloy for electrical and electronic equipment excellent in punching work, characterized by containing 0.5 wt%.

The invention according to claim 18 is characterized in that the diameter of a crystallized substance or a precipitate is 5 μm or less.
18. A copper alloy for electrical and electronic equipment excellent in punching workability according to any one of 17.

The invention according to claim 19 is characterized in that the crystal grains have a diameter of 30 μm.
18. The copper alloy for electrical and electronic equipment excellent in punching workability according to any one of claims 1 to 17, wherein the copper alloy is less than m.

The invention according to claim 20 is characterized in that the diameter of the crystallized substance or precipitate is 5 μm or less and the diameter of the crystal grains is less than 30 μm. It is a copper alloy for electrical and electronic equipment that has excellent punchability.

According to a twenty-first aspect of the present invention, when a copper alloy having the composition described in any one of the first to seventeenth aspects is subjected to casting, hot working and cold working, the cooling rate during the casting is reduced. The copper alloy ingot obtained by the casting process is heated to 700 to 1000 ° C., hot-worked, quenched at a rate of 10 ° C./sec or more after hot working, and then cold-cooled. This is a method for producing a copper alloy for electrical and electronic equipment excellent in punching workability, characterized by performing at least one heat treatment of heating at 300 to 600 ° C. for 30 seconds to 6 hours.

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claims 1 to 11 is a commonly used copper alloy (base metal) for electric and electronic equipment.
And at least one element selected from the group consisting of Pb, Bi, Ca, Sr, Ba, and Te (selective element group A) is added in an appropriate amount to improve the punching workability of the copper alloy for electric and electronic devices. is there. Here, the punching workability is evaluated based on the degree of occurrence of punching burrs, the dimensional accuracy and shape of the punched end face, the life of the punching die, and the like.

The alloy element is a simple compound of itself,
It is dispersed in a copper matrix as a compound with Cu, a compound between alloying elements, or the like. That is, Pb and Bi are single compounds, and Ca, Sr, Ba and Te are compounds with Cu, respectively, which are crystallized or precipitated and dispersed in a copper matrix. The former is mainly for the above-mentioned improvement, and the latter is mainly for the above-mentioned improvement. Each contributes to the above improvement. When two or more of these elements are added, a synergistic effect that each element is finely dispersed while bonding to each other is obtained, and all of the above-described punching workability is further improved. In particular, the combination of at least one of Pb and Bi and at least one of Ca, Sr, Ba, and Te significantly improves the punching workability. The reason for limiting the total content of these elements to 0.005 to 0.2 wt% is that if the content is less than 0.005 wt%, the effect of improving the punching workability cannot be sufficiently obtained. This is because defects such as cracks occur during hot working or cold working. The addition of the selective element group A is required for a copper alloy for electric / electronic equipment such as strength, conductivity, heat resistance, spring property, bending property, plating property, solderability, etc., if it is an appropriate amount. There is no loss of characteristics.

[0028] The inventions of claims 12 to 17 correspond to claims 1 to 11
In addition to the invention copper alloy described, Sn, Cr, Mg, Zr,
The alloy contains at least one element group of Ni, Ag, and Mn (selective element group B). These elements do not impair the punching workability, and the strength, heat resistance, and bending strength of the copper alloy. Workability, fatigue resistance, stress relaxation, spring, plating,
Improves solderability, migration resistance, etc. The reason that the content of the selected element group B is limited to a total of 0.01 to 0.5 wt% is that if the content is less than 0.01 wt%, the effect is not sufficiently obtained, and if the content exceeds 0.5 wt%, the electrical conductivity is lowered, and This is because workability deteriorates. In addition to the above elements, Si, Al, Z
n, Co, Fe, Ti, V, Hf, As, Sb, P,
Similar effects are observed for B, C, and the like.

The base metal used in the present invention is usually
Copper or copper alloy used for lead frames, terminals, connectors, power distribution components, and the like. That is, Cu-
Solid solution alloys such as Zn, Cu-Sn, Cu-Sn-Ni, Cu-Ni, Cu-Ni-Zn, Cu-Zr, Cu-Fe, Cu-Cr, Cu- Cr-
Zr, Cu-Mg, Cu-Co, Cu-Ti, Cu-Be, Cu-N
Precipitated alloys such as i-Ti, Cu-Fe-Ti, Cu-Ni-Si, and Cu-Ni-Sn, and pure copper-based alloys such as oxygen-free copper, tough pitch copper, and copper containing Ag.

In the present invention, among the copper alloys for electric and electronic equipment, Cu-Zr alloy, Cu-Sn-Ni-P alloy, Cu-Fe-P alloy, Cu-Fe-Zn-P alloy Limits the amount of alloying elements, and the reasons for the limitation are described below. In a Cu-Zr-based alloy (claim 3),
Zr is finely precipitated as a Cu-Zr-based compound in a copper matrix and improves strength and heat resistance without significantly lowering the electrical conductivity. The reason for limiting the content to 0.02 to 0.2 wt% is that if the content is less than 0.02 wt%, the effect cannot be obtained sufficiently, and
If it exceeds 2 wt%, the conductivity decreases and Cu-Zr
This is because the system compound becomes coarse and the Ag plating property and the punching workability decrease. In this alloy, the oxygen content is 0.
If the content is less than 005 wt%, the effect of Zr will appear even more.

In a Cu—Sn—Ni—P alloy (Claim 6), Sn and Ni are important elements that affect strength, conductivity, and other main characteristics. A 2 wt% Sn-0.2 wt% Ni alloy is used. In the copper alloy, Sn forms a solid solution in a copper matrix and improves strength without impairing bending workability. The reason for limiting the content to 1.5 to 2.5 wt% is as follows.
If the content is less than 5 wt%, sufficient strength cannot be obtained, and if the content exceeds 2.5 wt%, the electrical conductivity is significantly reduced and the hot workability is deteriorated. Like Ni, Ni forms a solid solution in a copper matrix to contribute to strength improvement, and is also effective in heat resistance, corrosion resistance, crystal grain refinement, and the like. Ni content 0.1 ~ 0.
The reason why the content is limited to 3 wt% is that if the content is less than 0.1 wt%, the effect cannot be sufficiently obtained, and if the content is more than 0.3 wt%, the conductivity is significantly reduced. P acts as a deoxidizing material during casting and remains in the alloy after that. If its amount exceeds 0.15 wt%, workability and solderability deteriorate.

Cu-Fe-P alloy (claim 8)
Is an alloy suitable for applications requiring conductivity. In this alloy, a part of Fe forms a solid solution in a copper matrix, and the other forms a compound with P to precipitate finely, thereby improving strength and heat resistance without significantly lowering conductivity. 0.02 ~
The reason why the content is limited to 0.5 wt% is that if the content is less than 0.02 wt%, the effect cannot be sufficiently obtained, and if the content exceeds 0.5 wt%, the decrease in conductivity becomes large. P forms a compound with Fe and contributes to improvement in strength and heat resistance. The reason for limiting the content to 0.01 to 0.2 wt% is that if the content is less than 0.01 wt%, the effect cannot be sufficiently obtained, and if the content exceeds 0.2 wt%, the decrease in conductivity becomes large.

The Cu-Fe-Zn-P-based alloy (claim 9) is an alloy suitable for applications requiring strength. Where F
The reason for limiting the content of e to 1.0 to 2.6 wt% is that if the content is less than 1.0 wt%, sufficient strength improvement cannot be obtained, and if it exceeds 2.6 wt%, the strength improvement effect is saturated, and crystallized substances and precipitation This is because the size of the product becomes large, and the punching workability and the plating property deteriorate. The reason why the content of P is limited to 0.015 to 0.15 wt% is that if the content is less than 0.015 wt%, the effect cannot be sufficiently obtained.
If it exceeds 5 wt%, the solder peeling resistance is significantly reduced. Zn contributes to improvement of solderability and solder plating property. The reason for limiting the content to 0.05 to 2.0 wt% is that
If the amount is less than 5% by weight, the effect cannot be sufficiently obtained. If the amount exceeds 2.0% by weight, the solderability is rather deteriorated. The copper alloy of the present invention can be used not only as ordinary strips and plate materials, but also as irregularly shaped strips having an uneven cross section.

As described above, the copper alloy for electrical and electronic equipment of the present invention is different from the conventional copper alloy for electrical and electronic equipment in that the selected element group A (Pb, Bi, Ca, S
By adding an appropriate amount of at least one element of (r, Ba, Te), the punching workability is improved without deteriorating the characteristics as a copper alloy for electric / electronic equipment. Also,
Further, the selected element group B (Sn, Cr, Mg, Zr, N
(i, Ag, Mn) by adding an appropriate amount of at least one of the elements described above to improve the properties as a copper alloy for electric and electronic equipment.

The invention according to claims 18 to 20 is characterized in that the size of a crystallized substance or a precipitate in the invention copper alloy is limited to less than 5 μm,
Or, further improved punching workability by limiting the size of crystal grains to less than 30 μm, or limiting the size of crystallized substances or precipitates to less than 5 μm and the size of crystal grains to less than 30 μm. It is. The reason for limiting the size of the crystallized substance or the precipitate to less than 5 μm is that when the size of the crystallized substance or the precipitate exceeds 5 μm, the above-mentioned improvement effect, which is one of the indexes of punching workability, is reduced. To do that. The reason why the crystal grain size is limited to less than 30 μm is that if it exceeds 30 μm, the above-mentioned improvement effect is reduced.

The invention according to claim 21 is a method for producing a copper alloy according to claims 18 to 20. In the present invention, the reason why the cooling rate when casting a molten metal adjusted to a predetermined component is limited to 5 ° C./sec or more is that when the cooling rate is less than 5 ° C./sec, the size of the crystallized material is 5 μm or less. Because it cannot be done. Set the ingot heating temperature and hot working temperature before hot working to 7
The reason why the temperature is limited to 100 to 1000 ° C. is that the workability is poor at a temperature lower than 700 ° C., and the size of a crystallized substance or a precipitate cannot be reduced to 5 μm or less at a temperature higher than 1000 ° C.

The reason why the cooling rate after hot working is limited to 10 ° C./sec or more is that if the cooling rate is less than 10 ° C./sec, the size of a crystallized substance or a precipitate cannot be reduced to 5 μm or less. The heat treatment is performed during the cold working in order to release the strain and improve the workability and to restore the conductivity. The heat treatment temperature is limited to 300 to 600 ° C. and the heat treatment time is limited to 30 seconds to 6 hours. The reason for this is that the strain relief and the recovery of the conductivity cannot be sufficiently obtained even at a temperature lower than 300 ° C. or for a time shorter than 30 seconds.
And the crystal grain size exceeds 30 μm.

Further, after subjecting the plate material obtained by the invention of claim 21 to cold working at a cross-sectional reduction rate of 60% or more,
By performing annealing without recrystallization in the temperature range of 200 to 500 ° C, the characteristics required for electrical and electronic equipment such as elongation, bending workability, anisotropy, internal stress, and spring properties are further improved. . Heat treatment at 300-600 ° C and 200-
Annealing at 500 ° C. may be performed by either a batch system or a continuous system. If a straightening process such as a tension leveler or a roller leveler is performed before, after or both before and after the annealing at 200 to 500 ° C., the dimensional accuracy of the member for electric and electronic equipment is improved.

[0039]

The present invention will be described below in detail with reference to examples. (Example 1) Alloys having compositions shown in Tables 1 to 8 (base metals containing at least one selected element group A such as Pb, Bi, Ca, Sr, Ba, and Te) are melted by a high-frequency melting furnace. Then, at a cooling rate of 6 ° C./sec, the thickness is 30 mm and the width is
It was cast into an ingot of 100 mm and length of 150 mm. Next, this ingot
It was hot rolled at 980 ° C. to 12 mm and immediately quenched at a rate of 30 ° C./sec. In order to remove the oxide film from the hot-rolled material, it was chamfered to a thickness of 9 mm, cold-rolled to a thickness of 1.2 mm, and then annealed at 550 ° C. for 2 hours in an inert gas atmosphere. After cold rolling to 530 ° C., heat treatment was performed at 530 ° C. for 1 hour in an inert gas atmosphere, and then finish rolling was performed to 0.2 mm. Thereafter, annealing was performed at 300 ° C. for 2 hours in an inert gas atmosphere to obtain a plate material. For comparison, a plate of 0.2 mm was manufactured under conditions other than the conditions of the present invention.

With respect to each of the sheet materials thus obtained, the size of crystallized material or precipitate, crystal grain size, and punching workability were examined by the following methods. Size of crystallized product or precipitate: Ten sizes were measured by observation with a scanning electron microscope (× 1000) and expressed as an average value. Crystal grain size: The average particle size in the visual field was measured with an optical microscope (200 times). Punching workability: A 1 mm x 5 mm square hole was made with a SKD11 mold, and 20 samples were randomly extracted from the 5001st to 10000th punchings, and the burr height I of these samples was measured. . The thickness a of the fractured part was measured by observing the punched surface, and the ratio of the fractured part to the thickness b of the test piece (a / b)
× 100% was determined. This broken portion ratio is regarded as one of the standards of the punching workability. The larger this value is, the better the punching workability is, and it is evaluated that the yield was improved and the precision processing was performed. In addition, regarding the mold life, 500
Twenty samples were randomly extracted from the punching from the 01st to the 55000th, and the burr height II was measured and evaluated. The size of the burrs increases as the mold wear increases, and serves as an index of the mold life. Burr height I, II
Was performed using a needle contact shape measuring instrument. Tables 1 to 8 show the results.
Shown in

[0041]

[Table 1]

[0042]

[Table 2]

[0043]

[Table 3]

[0044]

[Table 4]

[0045]

[Table 5]

[0046]

[Table 6]

[0047]

[Table 7]

[0048]

[Table 8]

As is clear from Tables 1 to 8, all of the examples of the present invention were excellent in punching workability. In contrast, Table 1
Comparative Example No. 8 of No. 8 has a small addition amount of the selected element group A,
The burr heights I and II increase, the fracture surface ratio also decreases, and no improvement in punching workability is seen. Further, Comparative Example No. 2 in Tables 1 to 8 was not able to be manufactured due to cracking during hot and cold working due to the large addition amount of the selected element group A. Tables 1-8
In Comparative Example No. 3 of No. 3, the burr height I was small but the burr height II was large because the size of the crystallized substance or the precipitate was large, and the effect of improving the punching workability was reduced by half. Further, Comparative Example No. 4 in Tables 1 to 8 has a large crystal grain size, so that the burr heights I and II increase, the fracture surface ratio decreases, and the effect of improving the punching workability is hardly recognized. Was.

In the above embodiment, the case where the sheet material is manufactured by a process including hot working has been described. However, since a phosphor bronze alloy containing 4 wt% or more of Sn is difficult to hot work, a thin plate is formed by a horizontal continuous casting method. A method of casting and directly cold-working this is used. Therefore, phosphorous bronze alloys containing 3 to 9 wt% of Sn and 0.03 to 0.35 wt% of P are added to Pb and B.
An alloy containing at least one of the elements i, Ca, Sr, Ba, and Te in an amount of 0.002 to 0.5 wt% is cast into a thin ingot having a thickness of 10 mm by a horizontal continuous casting method, and after homogenization, Then, the sheet was cold-rolled while being annealed to a thickness of 0.2 mm, and then annealed at 300 ° C. for 2 hours in an inert gas atmosphere to obtain a sheet. The same investigation as in Example 1 was performed on this sheet. . As a result, it was confirmed that even a phosphor bronze alloy containing a large amount of Sn can obtain good properties such as punching workability. When using this horizontal continuous casting method,
Since a hot working step is not included, sufficient attention must be paid to control of crystallized matters, precipitates, crystal grain size and the like to be small.

Example 2 A 1.2 mm thick cold-rolled material was annealed at 530 ° C. for 1 hour in an inert gas atmosphere using a copper alloy having the composition shown in Table 9. A plate material is produced by the same method as described above, and the size of crystallized material and precipitate, crystal grain size, strength, conductivity, heat resistance, Ag
Plating properties, flash heights (I, II), and fracture ratios were examined. The copper alloy is a copper alloy obtained by adding the selective element group A or both the selective element group A and the selective element group B to a Cu-Zr-based alloy.

The size of the crystallized product and the precipitate was measured by scanning electron microscope observation (× 1000), and the average value was determined. The average grain size in the visual field was measured with an optical microscope (200 times) for the crystal grain size. The tensile strength was measured according to JISZ2241. The conductivity was measured according to JISH0505. The Ag plating property is as follows: After a test specimen of 40 mm x 100 mm is electrolytically degreased, it is acid-washed with a 10% sulfuric acid solution, plated with Ag in a cyan bath with a thickness of 5 μm, and heated in air at 450 ° C for 10 min. Microscope (20
), The presence or absence of surface swelling was visually observed. When swelling was clearly observed in this observation, it was determined to be defective. The peeling resistance of the solder was determined by immersing it in a eutectic solder (Pb-63wt% Sn) bath at 230 ° C for 5 seconds, attaching the solder to the surface, heating in air at 150 ° C for 1000 hours, and then heating at 180 ° C. After performing close contact bending and bending back, the state of peeling of the solder was visually observed. Punching workability was measured in the same manner as in Example 1. Table 10 shows the results.

[0053]

[Table 9]

[0054]

[Table 10]

As is clear from Table 10, No. 1 of the present invention example
Nos. To 12 were all excellent in characteristics. Among them, Nos. 8 to 12 are particularly excellent in strength, electrical conductivity, heat resistance, Ag plating property, etc. because the selected element group B is added. On the other hand, No. 1 of the comparative example was inferior in strength and heat resistance due to a small amount of Zr. No.2 has a large amount of Zr, so the conductivity decreases,
In addition, the size of crystallized substances and precipitates increased, and the burr height II, which is an index of mold wear, increased, resulting in a decrease in punching workability. The Ag plating swelled due to the heating. No. 3 of the comparative example has the burr heights I and II because the amount of the selected element group A is small.
, The fracture surface ratio was small, and the punching workability was poor.
Nos. 4 and 5 of the comparative examples cracked during hot and cold working and could not be worked. In Comparative Examples Nos. 6 and 7, since the number of selected element groups B was large, the conductivity was significantly reduced. Nos. 8 and 9 of Comparative Examples
The burr height II was increased due to the large size of the precipitates and precipitates, and the Ag plating was swollen by heating.
Nos. 10 and 11 of the comparative examples had a burr height I,
II was large, the fracture surface ratio was small, and the punching workability was poor.

(Example 3) A copper alloy having a composition shown in Table 11 was cold-rolled to a thickness of 0.33 mm without annealing a 9 mm-thick facing material, and this was heat-treated at 500 ° C for 2 hours. Was applied in an inert gas atmosphere, followed by finish rolling of 0.2 mm in thickness. Thereafter, the sheet was heat-treated at 200 ° C. for 1 hour in an inert gas atmosphere to produce a sheet material. Regarding the obtained plate material, the size of crystallized substance and precipitate, crystal grain size, strength, conductivity, punching workability (burr height I, II, fractured portion ratio, lead displacement), heat resistance (solder The presence or absence of peeling of the plating layer and the Ag plating layer after heating were examined. Table 12 shows the results. In addition, the said copper alloy is Cu-S
This is a copper alloy obtained by adding a selection element group A to an n-Ni- (P) -based alloy. Among the above-mentioned investigation items, the punching workability, the mold life and the solder releasability were investigated by the following method, and other than that, they were investigated by the same method as in Example 1 or Example 2. [Punching workability] Using a SKD11 mold, lead frame (lead width 0.25mm, lead pitch 0.4mm, lead length 20)
mm, 4 leads), and 20 samples were extracted at random from the punching up to the 1000th punching, and the following items (a), (b) and (c) were measured and evaluated. The lead frame was punched so that its length direction was perpendicular to the rolling direction of the sheet material. (a) Breakage ratio: The cutout side fracture surface of the No. 3 lead was observed and evaluated in the same manner as in Example 1.
(b) Displacement of the lead: The amount of displacement in the horizontal direction at the inner side of the lead No. 3 was measured 300 times and measured. The displacement from the target position was obtained as an absolute value. (c) Burr height I: The burr height of the third lead was measured with a needle contact type shape measuring instrument. [Mold life] A square die of 2 mm x 4 mm was used.
After the mold was re-polished, 20 samples were randomly extracted from the 500,000 to 501,000 times punching, and the burr height II at the corner was determined. The burr height II increases as the mold wear increases, meaning that the mold wear has progressed. The burr heights I and II were measured using a needle contact type measuring instrument as in Example 1. [Solder peelability] Sn-10% Pb solder is plated to a thickness of 1 μm and heated in the air at 150 ° C. for 1000 hours.
A V-bending test was performed, and the presence or absence of solder peeling at the bent portion was visually observed.

[0057]

[Table 11]

[0058]

[Table 12]

As is clear from Table 12, No. 1 of the present invention example
Nos. To 12 were all excellent in characteristics. On the other hand, Comparative Example No. 13 having a small amount of Sn had low strength, and No. 14 had a large amount of Sn, so that cracks occurred during hot working and production was impossible.
In No. 15 of the comparative example, since the Ni content was large, the electrical conductivity was significantly reduced. In Nos. 16 to 18, the selectable element group A was small, so that the punching workability was reduced. In Comparative Examples Nos. 19 to 23, the added amount of the selected element group A was large, so that cracks occurred during hot working (Nos. 20, 21, and 22), and crystallization or wear of the mold due to coarsening of precipitates occurred. Becomes severe (No. 19, 23), and solder peeling is likely to occur,
Also, the Ag plating property was inferior. In No. 24, since the P content was large, coarse crystals were formed, and the abrasion of the mold was accelerated.
Also, the solder peeling resistance and the heat swelling resistance of Ag plating were inferior.

Example 4 Using an alloy having the composition shown in Table 13, a plate was produced in the same manner as in Example 2, and the obtained plate was investigated in the same manner as in Example 1. Table of results
See Figure 14.

[0061]

[Table 13]

[0062]

[Table 14]

As is clear from Table 14, No. 1 of the present invention example
~ 12 all had excellent characteristics. In contrast, the comparative example
In Nos. 1 and 3, both the strength and the heat resistance decreased because the amounts of Fe and P were small. In Comparative Examples Nos. 2 and 4, the electrical conductivity decreased due to the large amounts of Fe and P. In Comparative Example No. 5, the burr heights I and II were large because the amount of the selected element group A was small, and the fracture surface ratio was small.
Punching workability was poor. Conversely, in Comparative Examples Nos. 6 and 7 in which the amount of the selected element group A was large, cracks occurred during hot and cold working and production was not possible. Nos. 8 and 9 have a large decrease in conductivity due to the large number of selected element groups B. In Nos. 10 and 11, the Ag plating layer swelled after heating, and the burr height as an index of mold wear was large. In Nos. 12 and 13, both the burr heights I and II were large, the percentage of breakage was small, and the punching workability was poor.

Example 5 Using an alloy having the composition shown in Table 15, a plate was produced in the same manner as in Example 3, and the obtained plate was investigated in the same manner as in Example 1. Table of results
See Figure 16.

[0065]

[Table 15]

[0066]

[Table 16]

As is clear from Table 16, No. 1 of the present invention example
Nos. To 12 had excellent properties. On the other hand, N
In the case of o.13, the strength decreased due to the small amount of Fe. N in Comparative Example
In o.14, since the amount of Fe was large, the conductivity was low, and solder peeling was also observed. No. 15 had a high P content due to a large amount of P, and solder peeling was also observed. In No. 16, the strength was reduced due to the small amount of P. In No. 17, solder peeling was observed because of a small amount of Zn, and in No. 18, solder wettability was reduced because of a large amount of Zn.
In No. 19, the punching workability was reduced due to the small number of the selected element group A. In Nos. 20 and 21, cracks occurred during hot working due to the large number of selected element group A. In Nos. 22 and 23, the conductivity was reduced due to the large number of the selected element group B. In Nos. 24 and 25, the Ag plating layer swelled due to heating due to the large size of the crystal deposits and precipitates. Also, the burr height II, which is an indicator of mold wear, increased. No.2
6, 27 have large burr heights I and II due to large crystal grain size,
The fracture ratio was small, and no effect of improving the punching workability was observed.

(Example 6) Using an alloy having a composition of Nos. 1, 5, and 11 shown in Table 11, casting, hot rolling,
A plate was manufactured in various steps of repeating cold working and annealing, and the obtained plate was subjected to the same investigation as in Example 3 and to the bending workability. For bending workability, bending was performed at 90 degrees so that the bending axis was parallel or perpendicular to the rolling direction. The minimum bend and radius at which cracks did not occur were determined. If the difference between the minimum bend radius in equilibrium bending and right-angle bending was 0.2 mm or more, it was determined that there was anisotropy. The results are shown in Table 18. Table 18 shows Nos. 1, 5, and 11 again.

[0069]

[Table 17]

[0070]

[Table 18]

As is clear from Table 18, the No. of the present invention example
25 to 33 all had excellent characteristics. In contrast, the comparative example
Nos. 34 and 41 had slow cooling rates during casting,
In Nos. 36 and 45, the cooling rate after hot working was low because the hot working temperature was low, so that the crystallization and precipitates became coarser and the burrs after mold abrasion increased in each case. No.38,43
Since the heat treatment temperature at the time of cold working was high, the crystal grain size was large, and the burr heights I and II were large as compared with Nos. 1 and 5 of the present invention. Conversely, Nos. 39 and 44 did not recrystallize sufficiently due to the low annealing temperature, and the anisotropy was large. In particular, bending workability in an axis parallel to the rolling direction was poor. In Nos. 37 and 40, since the hot working temperature exceeded 1000 ° C., a thick oxide film was formed on the rolled material. These characteristics are equivalent to those of Nos. 1 and 5 of the present invention, and it can be understood that hot working at a temperature exceeding 1000 ° C. only increases the energy cost and is meaningless.

[0072]

As described above, in the copper alloy of the present invention, at least one of the elements Pb, Bi, Ca, Sr, Ba, and Te is a simple compound, a compound with Cu, Since it is dispersed in the copper matrix as a compound between the two, it has excellent punching workability. By limiting the size of the crystallized substance or precipitate to 5 μm or less and / or the crystal grain size to less than 30 μm, the punching workability is further improved. The copper alloy of the present invention can be easily manufactured by performing ordinary melting, casting, hot rolling, and cold rolling under predetermined conditions. Therefore, it is possible to fully cope with high integration, miniaturization, low cost, etc. of electrical and electronic equipment parts to be punched such as lead frames, terminals, connectors, switches, contacts, and general conductive materials. It has a remarkable effect.

Claims (21)

[Claims] 1. Cu is composed of Pb, Bi, Ca, Sr, Ba,
A copper alloy for electrical and electronic equipment excellent in punching workability, characterized by containing at least one of the elements of Te in an amount of 0.002 to 0.5 wt%. 2. A Cu—Zn based alloy containing Pb, Bi, Ca,
At least one of the elements Sr, Ba and Te is 0.0
A copper alloy for electrical and electronic equipment with excellent punching characteristics characterized by containing 02 to 0.5 wt%. 3. Cu-Zr containing 0.02-0.2 wt% of Zr
A copper alloy for electric and electronic equipment excellent in punching workability, characterized in that at least one of elements of Pb, Bi, Ca, Sr, Ba, and Te is contained in a system alloy at 0.002 to 0.5 wt%. 4. A Cu—Sn based alloy containing Pb, Bi, Ca,
At least one of the elements Sr, Ba and Te is 0.0
A copper alloy for electrical and electronic equipment with excellent punching characteristics characterized by containing 02 to 0.5 wt%. 5. A Cu—Sn—Ni alloy containing Pb, Bi,
A copper alloy for electrical and electronic equipment excellent in punching workability, characterized by containing at least one of Ca, Sr, Ba and Te elements in an amount of 0.002 to 0.5 wt%. 6. Sn is 1.5 to 2.5 wt% and Ni is 0.1 to 0.3 watts.
Cu-Sn-Ni-P based alloy containing 0.15 wt% or less of t% and P contains at least one of Pb, Bi, Ca, Sr, Ba, and Te elements in an amount of 0.002-0.5 wt%. A copper alloy for electrical and electronic equipment with excellent punching work characteristics. 7. Pb, Bi, Ca, Cu-Fe alloys
At least one of the elements Sr, Ba and Te is 0.0
A copper alloy for electrical and electronic equipment with excellent punching characteristics characterized by containing 02 to 0.5 wt%. 8. An Fe content of 0.02 to 0.5 wt% and a P content of 0.01 to 0.2 wt%.
Pb, Bi, Ca, S
at least one of the elements r, Ba and Te is 0.002
A copper alloy for electrical and electronic equipment with excellent punching workability, characterized by containing up to 0.5 wt%. 9. An Fe content of 1.0 to 2.6 wt% and a Zn content of 0.05 to 2.0 watts.
Cu-Fe-Zn- containing 0.15 to 0.15 wt% P
A copper alloy for electrical and electronic equipment having excellent punching characteristics, characterized in that a P-based alloy contains at least one element of Pb, Bi, Ca, Sr, Ba, and Te in an amount of 0.002 to 0.5 wt%. . 10. A Cu—Cr alloy containing Pb, Bi, Ca,
At least one of the elements Sr, Ba and Te is 0.0
A copper alloy for electrical and electronic equipment with excellent punching characteristics characterized by containing 02 to 0.5 wt%. 11. A Cu—Cr—Zr alloy containing Pb, Bi,
A copper alloy for electrical and electronic equipment excellent in punching workability, characterized by containing at least one of Ca, Sr, Ba and Te elements in an amount of 0.002 to 0.5 wt%. 12. The copper alloy according to claim 1, further comprising Sn, Cr, M
A copper alloy for electrical and electronic equipment excellent in punching workability, characterized by containing at least one of g, Zr, Ni, Ag, and Mn elements in a total amount of 0.01 to 0.5 wt%. 13. The copper alloy for electric / electronic equipment according to claim 3, further comprising at least one of Sn, Cr, Mg, Ni, Ag, and Mn in a total amount of 0.01 to 0.5 wt%. A copper alloy for electrical and electronic equipment which is excellent in stamping workability. 14. The copper alloy for electrical and electronic equipment according to claim 4, further comprising at least one of Cr, Mg, Zr, Ni, Ag, and Mn elements in a total amount of 0.01 to 0.5 wt%. A copper alloy for electrical and electronic equipment which is excellent in stamping workability. 15. The copper alloy for electrical and electronic equipment according to claim 5, further comprising Cr, Mg, Zr, Ag, M
at least one of the n elements is 0.01 to 0.5 wt% in total
A copper alloy for electric and electronic equipment, which is excellent in punching workability, characterized by being contained. 16. The copper alloy for electric / electronic equipment according to claim 10, further comprising at least one of Sn, Mg, Zr, Ni, Ag, and Mn elements in a total amount of 0.01 to 0.5 wt%. A copper alloy for electrical and electronic equipment which is excellent in stamping workability. 17. The copper alloy for electrical and electronic equipment according to claim 11, further comprising at least one of Sn, Mg, Ni, Ag, and Mn elements in a total amount of 0.01 to 0.5 wt%. Copper alloy for electrical and electronic equipment with excellent punching workability. 18. The copper alloy for electrical and electronic equipment excellent in punching workability according to claim 1, wherein a diameter of a crystallized substance or a precipitate is 5 μm or less. 19. The copper alloy for electric and electronic equipment excellent in punching workability according to claim 1, wherein the crystal grains have a diameter of less than 30 μm. 20. A crystal or precipitate having a diameter of 5 μm or less,
18. The copper alloy for electrical and electronic equipment excellent in punching workability according to claim 1, wherein the crystal grains have a diameter of less than 30 [mu] m. 21. A casting, hot working, and cold working of a copper alloy having a composition according to any one of claims 1 to 17, wherein the cooling rate during the casting is 5 ° C./sec or more. ,
The copper alloy ingot obtained by the casting process is heated to 700 to 1000 ° C., hot worked, rapidly cooled at a rate of 10 ° C./sec or more after the hot working, and then cold worked, A method for producing a copper alloy for electrical and electronic equipment having excellent punching workability, wherein a heat treatment of heating at 600 ° C. for 30 seconds to 6 hours is performed at least once.