TWI589715B - Copper alloy strip and with its high-current electronic components and cooling electronic components - Google Patents

Description

Copper alloy strip and electronic component for high current therewith and electronic component for heat dissipation

The present invention relates to a copper alloy strip, and in particular to an excellent heat dissipation, electrical conductivity, strength and bending workability, and is suitable for use in electronic parts such as terminals, connectors, relays, switches, sockets, bus bars, lead frames, and the like. It is especially suitable for heat-dissipating parts used in smart phones, personal computers, etc., as well as copper alloy strips used for high-current parts used in electric vehicles or hybrid vehicles.

In motors, electronic devices, etc., such as smart phones, tablet PCs, and personal computers, terminals, connectors, switches, sockets, relays, bus bars, lead frames, and the like for obtaining electrical connections and for distributing equipment are embedded. Hot parts that are emitted.

In recent years, with the miniaturization of smart phones, tablet PCs, and personal computers, heat storage during power-on of liquid crystal components or IC chips in motors and electronic devices tends to increase. Since the thermal storage of the IC wafer and the substrate is large due to the large state of heat storage, the heat dissipation of the heat dissipating component becomes a problem.

In the past, in the heat-dissipating parts of electrical and electronic equipment such as smart phones, tablet PCs, and personal computers, Worthite iron-based stainless steel was mainly used (for example, in JIS G 4304 "Hot-rolled stainless steel sheets and steel strips" SUS304) and pure aluminum. For example, in a heat dissipating part (liquid crystal frame) attached to a liquid crystal of a smart phone or a tablet PC, in addition to high heat dissipation In addition to the properties, the strength as a structure and the bending workability required for fixing the liquid crystal are also required.

Although the Vostian iron-based stainless steel (SUS304) has good bending workability, it has low thermal conductivity, and in order to compensate for the low thermal conductivity, a high-priced heat conduction sheet or the like is used in combination. Therefore, the unit price of the heat dissipating component becomes high. On the other hand, although pure aluminum and an aluminum alloy have good bending workability, thermal conductivity and strength as a structure are insufficient.

Further, in the energized components such as the terminals and the connectors, the cross-sectional area of the copper alloy in the current-carrying portion tends to be small. When the cross-sectional area becomes small, heat generation from the copper alloy increases when energized. In particular, in an electronic component used in an electric vehicle or a hybrid vehicle which is significantly increased, there is a problem that a high current is likely to flow through a connector such as a battery unit, and heat generation of the copper alloy at the time of energization becomes a problem. Therefore, in order to reduce the amount of heat generation, the conductive material is required to have excellent electrical conductivity, and in order to cope with the miniaturization and high performance of the component, strength (especially a high 0.2% proof stress) and excellent bending workability are required.

It is known that thermal conductivity and electrical conductivity are proportional. In view of the above requirements, as an alloy having high electrical conductivity and strength, a material in which Zr, Cr, and Ti are added to Cu is known. For example, in CDA (Copper Development Association), C15100 (0.1% by mass Zr-remaining Cu), C15150 (0.02% by mass Zr-remaining Cu), C18140 (0.1% by mass Zr-0.3% by mass Cr) are registered. - 0.02% by mass Si - Remaining Cu), C18145 (0.1% by mass Zr - 0.2% by mass Cr - 0.2% by mass Zn - Remaining Cu), C18070 (0.1% by mass Ti - 0.3% by mass Cr - 0.02% by mass Si- The remaining alloys are Cu), C18080 (0.06 mass% Ti-0.5 mass% Cr-0.1 mass% Ag-0.08 mass% Fe-0.06 mass% Si-remaining Cu).

Although a certain degree of strength is required for the heat dissipating component and the copper alloy for electronic materials, for example, in the above alloy, the Cu-Zr alloy such as C15100 may have insufficient strength.

On the other hand, although the Cu-Cr-Zr alloy such as C18140 generally has a 0.2% proof stress better than C15100, the melting of Cr to the Cu alloy is very difficult. Therefore, in recent years, an invention has been made to improve the strength, electrical conductivity, and bending workability of a Cu-Zr alloy having a relatively low manufacturing difficulty.

Patent Document 1 discloses a copper alloy having a good balance of strength, electrical conductivity, and bending workability by performing a treatment as follows: a copper alloy containing Zr in a range of 0.05% to 0.3% by weight, in heat After the rolling, a first cold rolling, a first heat treatment, a second cold rolling, and a second heat treatment in which tension is simultaneously applied are performed.

Patent Document 2 discloses a copper alloy in which a Brass orientation of a textured Brass orientation is 20 or less in a copper alloy containing Zr in a range of 0.01% by mass to 0.5% by mass, and Brass The azimuth distribution density of the azimuth, the S-direction, and the Copper (copper) orientation is set to 10 or more and 50 or less, and has both strength and good bending workability.

Patent Document 3 discloses a copper alloy in which a copper alloy containing Zr in a range of 0.05% to 0.2% by weight ratio is used by a system with a backscattered electron image. The average value of the KAM value measured by the EBSD method by the scanning electron microscope is 1.5 to 1.8°. When the minimum bending radius without cracking is set to R in the W bending test, and the thickness is set to t, then R/t It is 0.1 to 0.6, and the elastic limit value is 420 to 520 N/mm ² , which is excellent in strength, elasticity, and bending workability.

Patent Document 4 discloses a copper alloy which achieves strength, bending workability, low Young's modulus (longitudinal elastic modulus, and deflection coefficient) by the following conditions: the total weight ratio is 0.05~ 1.0mass% of at least one of Cr, Zr, and Ti. In the crystal orientation analysis measured by EBSD, the area ratio of the Cube orientation {001}<001> is 5% or more, 70% Next, the Vickers hardness is 120 or more.

Patent Document 1: Japanese Laid-Open Patent Publication No. 2010-248592

Patent Document 2: Japanese Laid-Open Patent Publication No. 2010-242177

Patent Document 3: Japanese Laid-Open Patent Publication No. 2012-172168

Patent Document 4: Japanese Patent No. 5107916

However, in the inventions of Patent Documents 1 to 4, although a certain degree of mechanical strength and good bending workability are simultaneously provided, the strength and bending workability required for a copper alloy such as an electronic material in recent years are not necessarily sufficient. Specifically, in the examples of the inventions described in Patent Documents 1 to 3, the tensile strength of the Cu-Zr alloy is 457 to 560 MPa, and in the examples described in Patent Document 4, the 0.2% proof stress of the Cu-Zr alloy is At 425 MPa, tensile strength and 0.2% guaranteed stress are insufficient.

Further, although the patent document focuses on the improvement of tensile strength, in actual electronic parts, a high 0.2% proof stress is required. However, in the Cu-Zr alloy, even if the tensile strength is increased by work hardening, there is a problem that the 0.2% proof stress is not increased to a certain level or more (work hardening saturation). Further, since the Cu-Zr-based copper alloy undergoes precipitation hardening by aging and work hardening by rolling, the improvement of the strength of the patent document is mainly based on the control of crystal orientation.

Therefore, an object of the present invention is to provide a copper alloy strip having high strength, high electrical conductivity, and excellent bending workability as compared with a conventional material, and having a large copper strip. In particular, an object of the present invention is to improve the balance between strength (tensile strength and 0.2% proof stress), electrical conductivity, and bending workability.

The inventors performed the aging treatment of the Cu-Zr-based copper alloy strip twice or more, and found that good strength can be obtained by adjusting the conditions of cold rolling between aging temperature, aging and aging, and cold rolling after final aging. Conductivity and bending workability. Taking the above findings as a background, the following inventions were completed.

The Cu-Zr-based copper alloy strip of the present invention contains 0.04 to 0.5% by mass of Zr, and has a tensile strength of 550 MPa or more and a conductivity of 80% IACS or more.

Further, the ratio of the tensile strength (TS) and the 0.2% proof stress (YS) of the copper alloy strip of the present invention is preferably YS/TS. 0.9.

Further, the 0.2% proof stress of the copper alloy strip of the present invention after heating at 300 ° C for 30 minutes is preferably 500 MPa or more.

Further, in the copper alloy strip of the present invention, it is preferable that the X-ray diffraction integral intensity of the {200} plane obtained in the thickness direction is set to I in the rolling surface by the X-ray diffraction method. 200}, the integral intensity of the X-ray diffraction of the {111} plane is set to I{111}, the integral intensity of the X-ray diffraction of the {220} plane is set to I{220}, and the integral intensity of the X-ray diffraction of the {311} plane When set to I{311}, 0.1 [I{200}+I{111}+I{311}]/I{220} 0.6.

Further, the copper alloy strip of the present invention preferably contains at most one of 0.1% by mass of an element selected from the group consisting of Ag, Ni, Mn, Mg, Zn, Sn, B, and Ca.

The high-current electronic component and the heat-dissipating electronic component of the present invention include the copper alloy strip of any of the above.

According to the present invention, it is possible to provide a copper alloy strip having high strength, high electrical conductivity, and excellent bending workability. The copper alloy strip is suitable for use as a raw material suitable for use as an electronic component such as a terminal, a connector, a switch, a socket, a relay, a bus bar, a lead frame, a heat sink, and the like, and is used for a heat dissipating component such as a smart phone or a personal computer. And copper alloy strips for use in high-current electronic parts such as electric vehicles and hybrid vehicles.

Hereinafter, embodiments of the present invention will be described in detail.

(characteristic)

The copper alloy strip according to one embodiment of the present invention has an electrical conductivity of 80% IACS or more and a tensile strength of 550 MPa or more. When the electrical conductivity is 80% IACS or more, the thermal conductivity is also good, and there is no problem as a raw material for a large current electronic component and a heat dissipating component. Moreover, when the tensile strength is 550 MPa or more, it has the necessary strength as a structural material. Further, if the 0.2% proof stress/tensile strength is 0.9 or more, the spring characteristics required for electronic parts such as connectors, switches, sockets, and relay materials are required. When the 0.2% proof stress after heating at 300 ° C for 30 minutes is 500 MPa or more, it has heat resistance as a high-current electronic component and a heat-dissipating component. If the X-ray diffraction method using X-ray diffraction method has an integrated intensity of 0.1 [I{200}+I{111}+I{311}]/I{220} A range of 0.6 has good bending workability.

The copper alloy strip of the present invention having the above characteristics is suitable for use in electronic components for heat dissipation and high-current electronic components.

(alloy concentration)

The Cu-Zr-based alloy strip according to the embodiment of the present invention contains 0.040 to 0.50% by mass of Zr, and the total content of the Zr is preferably from 0.050 to 0.30% by mass, more preferably from 0.050 to 0.20% by mass. When the total of Zr is too small, it is difficult to obtain a tensile strength of 550 MPa or more. If the Zr concentration is too large, the production of the alloy becomes difficult due to hot rolling cracking or the like.

In the Cu-Zr-based alloy, one or more of Ag, Sn, Zn, Mg, Mn, B, and Ca may be contained in order to improve the strength and heat resistance. However, when the amount is too large, the electrical conductivity is lowered. When the IACS is less than 80%, or the manufacturability of the alloy deteriorates, the total amount of the added amount is at most 0.1% by mass.

(thickness)

The thickness of the product, that is, the thickness (t) is preferably 0.05 to 2.0 mm. If the thickness is too small, it is difficult to obtain sufficient heat dissipation properties, and thus it is not suitable as a raw material for electronic components for heat dissipation. On the other hand, if the thickness is too large, bending processing and drawing processing become difficult. From this point of view, a more preferable thickness is 0.08 to 1.5 mm. By setting the thickness to the above range, heat storage can be suppressed, and bending workability can be improved.

(Conductivity)

In the present invention, the conductivity measured according to JIS H0505 is set to 80% IACS or more. When the electrical conductivity is 80% IACS or more, the thermal conductivity is good, and good heat dissipation can be ensured. More preferably, it is set to 85% IACS or more.

(Tensile Strength)

In the present invention, when the tensile strength of the copper alloy strip is 550 MPa or more, the strength required for the raw material as the structural material is obtained. More preferably, it is set to 570 MPa or more.

(0.2% guaranteed stress)

In the present invention, the 0.2% proof stress/tensile strength (YS/TS) of the copper alloy strip is set to 0.9 or more, whereby the copper alloy strip has the elasticity required for the connector, the switch, and the relay material.

(heat resistance)

In the present invention, it is set to 0.2% guaranteed stress after heating at 300 ° C × 30 min. 500 MPa, thereby having heat resistance as a high-current electronic component and a heat-dissipating component.

(bending workability)

The evaluation of the bending workability of the present invention was carried out by using a W bending test (JIS-H3130) of a rectangular test piece having a width of 10 mm × a length of 30 mm. The test piece selection direction was set to the calendering parallel direction (GW) and the calendering orthogonal direction (BW), and was evaluated by the minimum bending radius MBR (Minimum Bend Radius) and the sheet thickness t ratio MBR/t. From the viewpoint of ensuring good bendability, the ratio (MBR/t) of the minimum bending radius (MBR) is preferably set to 2.0 or less. A more preferable range of MBR/t is 1.8 or less.

(crystal orientation)

When the X-ray diffraction method is used, the X-ray diffraction integral intensity of the {200} plane obtained in the thickness direction on the surface of the calendering surface is set to I{200}, and the X-ray diffraction integral intensity of the {111} plane is set. For I{111}, the X-ray diffraction integral intensity of the {220} plane is set to I{220}, and the X-ray diffraction integral intensity of the {311} plane is set to I{311}, at 0.1 [I{200}+I{111}+I{311}]/I{220} In the case of 0.6 (that is, 0.1 or more and 0.6 or less), the bending workability is improved. A more preferable range is 0.25 or more and 0.55 or less. On the other hand, when it deviates from the said range, bending workability is inferior. Further, the pure copper powder standard sample was defined as a copper powder having a purity of 99.5% of 325 mesh (JIS Z8801).

Hereinafter, an example of a preferred method for producing a copper alloy strip of the present invention will be described. Bright.

Electrolytic copper or the like which is a raw material of pure copper is melted, and Zr and other alloying elements as needed are added to cast an ingot having a thickness of about 30 to 300 mm. The ingot is hot-rolled into a plate having a thickness of about 3 to 30 mm by, for example, 800 to 1000 ° C, and then subjected to cold rolling and aging treatment twice or more, and finally processed into a predetermined product thickness by cold rolling, as the case may be. The relaxation annealing is performed at the end. It is also possible not to specifically perform relaxation annealing.

The aging treatment is carried out at a temperature of 300 ° C to 400 ° C for 2 or more times in the range of 1 to 30 hours. It is preferably 340 to 390 ° C, more preferably 350 to 390 ° C.

By performing annealing under appropriate conditions in which the rolled structure is not recrystallized, the work hardening by the subsequent rolling is increased, and the tensile strength of 550 MPa or more can be obtained. If the aging temperature is higher than 400 ° C, the strength of 550 MPa or more cannot be obtained. On the other hand, when the aging temperature is lower than 300 ° C, the electrical conductivity of 80% IACS or more cannot be obtained.

By adjusting the final aging temperature to a range of ±25 ° C relative to its previous aging temperature, the crystal orientation becomes 0.1. [I{200}+I{111}+I{311}]/I{220} In the range of 0.6, the bending workability was improved.

Further, when the final aging temperature is lower than the previous aging temperature by 0 to 25 ° C, the 0.2% proof stress after heating at 300 ° C × 30 min becomes 500 MPa or more. On the other hand, when the final aging temperature is high, the 0.2% proof stress after heating at 300 ° C for 30 minutes is 500 MPa or less, and the balance between strength, electrical conductivity, and bending workability is excellent, but from the viewpoint of heat resistance. There is room for improvement.

Further, by appropriately adjusting the conditions of the processing, etc., for example, the degree of processing between the aging treatment, the temperature of the first aging treatment, the processing degree of the final cold rolling, the concentration of Zr, and the addition The adjustment of elements and the like can be set to better tensile strength, electrical conductivity, and 0.2% proof stress.

YS/TS can be obtained by adjusting the cold rolling degree between aging and aging to 60% or more. 0.9. A better processing degree is 75% or more. If the cold rolling degree between aging and aging is less than 60%, YS/TS cannot be obtained. 0.9.

Although it is necessary to adjust the above-mentioned aging conditions and the degree of cold rolling between the aging treatments, the aging is not problematic for several times, but it is preferably two times in consideration of the manufacturing cost.

The cold rolling degree after the final aging is set to 50% to 80%. It is preferably 60 to 75%, more preferably 60 to 70%. If it is less than 50%, the tensile strength of 550 MPa cannot be obtained. If it is 80% or more, the Cu-Zr compound precipitated by aging is re-solidified in the matrix phase by rolling, and the electrical conductivity is lowered and becomes insufficient. 80% IACS.

The case where the relaxation annealing is performed is carried out using a continuous annealing furnace. The furnace temperature is set to 300 to 700 ° C, preferably 350 to 650 ° C, and is set to range from 5 seconds to 10 minutes. Relaxation annealing does not necessarily have to be implemented.

One embodiment of the present invention improves strength, electrical conductivity, and bending workability by imparting the following characteristics: tensile strength of a Cu-Zr alloy strip 550 MPa and electrical conductivity 80% IACS and YS/TS 0.2% guaranteed stress after heating at 0.9, 300 ° C × 30 min 500MPa, and 0.1 [I{200}+I{111}+I{311}]/I{220} 0.6. The manufacturing conditions for this will be summarized as follows:

(1) in order to make tensile strength 550MPa,

a. Adjust the aging temperature to less than 400 °C.

b. Adjust the final rolling machining degree to 50% or more.

(2) in order to make conductivity 80% IACS,

a. Adjust the aging temperature to 300 ° C or higher.

b. Adjust the final calendering degree to 80% or less.

(3) In order to make YS/TS 0.9,

a. Adjust the cold rolling degree between aging and aging to 60% or more.

(4) In order to make the 0.2% guaranteed stress after heating at 300 ° C × 30 min 500MPa,

a. Adjust the final aging temperature to 0 to 25 ° C lower than the previous aging temperature.

(5) In order to make 0.1 [I{200}+I{111}+I{311}]/I{220} 0.6,

a. The final aging temperature is adjusted to a range of ±25 ° C with respect to the previous aging temperature.

The copper alloy strips manufactured as described above are processed into a variety of sheet-thick stretched copper products, for example, high-current electronic parts and heat sinks for use in electrical/electronic equipment such as smart phones, tablet PCs, and personal computers. Use electronic parts and so on.

[Examples]

While the embodiments of the present invention are shown in the following, these embodiments are provided to provide a better understanding of the invention and its advantages. Further, in the following examples, although the example shows that the number of aging times is two, there is no problem even if the number of aging times is three or more.

After the alloying element was added to the molten copper, an ingot having a thickness of 200 mm was cast. The ingot was heated at 950 ° C for 3 hours and hot rolled at 950 ° C to obtain a plate having a thickness of 15 mm. The oxidized scale on the surface of the hot-rolled sheet is ground and removed by a grinder, and then subjected to aging and cold rolling, and finally cold-rolled to a predetermined product thickness. Finally, a continuous annealing furnace is used for the relaxation annealing.

In the initial aging, a fractional furnace is used, and the temperature is in the range of 200 to 500 ° C in the furnace, and heat treatment is performed in the range of 1 to 30 hours.

In the cold rolling after aging, the total degree of processing is controlled.

The final aging is also carried out using a fractional furnace in the range of 200 to 500 ° C in the furnace and heat treatment in the range of 1 to 30 hours. Various conditions are changed with respect to the initial aging temperature.

In the final cold rolling, the total degree of processing is controlled.

In the relaxation annealing, the furnace temperature was set to 500 ° C, and the heating time was adjusted to be between 1 second and 15 minutes. Furthermore, for some materials, relaxation annealing is omitted.

The production conditions of the examples are disclosed in Table 1 according to the invention examples and comparative examples. The following materials were measured for the materials in the middle of the manufacturing process and the materials after the relaxation annealing.

(ingredient)

The alloying element concentration of the material after the final cold rolling or after the relaxation annealing was analyzed by ICP-mass spectrometry. Further, an element having a component analysis value lower than 10 ppm in the table is not described.

(tensile strength and 0.2% guaranteed stress)

After the final cold rolling and the material after the relaxation annealing, the test piece No. 13B specified in JIS Z2241 was selected in parallel with the rolling direction and the rolling direction, and the tensile test was carried out in parallel with the rolling direction according to JIS Z2241. Tensile strength (TS) and 0.2% guaranteed stress (YS).

(heat resistance)

After holding the material for 30 min in a furnace set at 300 ° C, the sample taken out and air-cooled was measured to have a 0.2% proof stress in the same manner as described in "Tensile Strength and 0.2% Guaranteed Stress".

(Elongation)

The material after the final cold rolling or after the relaxation annealing, the direction parallel to the rolling direction The test piece No. 13B specified in JIS Z2241 was selected, and the distance between the punctuation points was set to 50 mm to measure the elongation.

(Conductivity)

From the material after the final cold rolling or after the relaxation annealing, the test piece was selected in such a manner that the longitudinal direction of the test piece was parallel to the rolling direction, and the electrical conductivity of 20 ° C was measured by a four-terminal method according to JIS H0505.

(crystal orientation)

The X-ray diffraction intensity I of the {200}, {111}, {311}, and {220} planes was measured for the surface of the calendered surface of the material after the final cold rolling or after the relaxation annealing. The X-ray diffraction apparatus was measured using a RINT 2500 manufactured by Rigaku Corporation under the conditions of a tube-shaped bulb of 25 kV and a tube current of 20 mA.

(MBR/t)

According to JIS H3130, the W-bend test of the GW (Goodway) direction in which the bending axis and the rolling direction are perpendicular directions, and the BW (Badway) direction in which the bending axis and the rolling direction are the same direction are performed, and the W-shaped mold is used to change the bending. Radius, find the ratio of the minimum bend radius (MBR) to the thickness (t) that does not cause cracking (MBR/t).

[Table 1]

As is clear from the contents shown in Table 1, in Examples 1 to 20, Zr is contained in a total amount of 0.04 to 0.50% by mass, and the first aging is performed at 300 to 400 ° C, and the subsequent cold rolling degree is adjusted to 60% or more. The final aging was carried out at 300 to 400 ° C, and the final cold rolling degree was adjusted to 50 to 80%, and finally the relaxation annealing was performed (the invention example 12 is omitted). Thus, the copper alloy strips of Inventive Examples 1 to 20 can achieve tensile strength. 550MPa, and 0.2% guaranteed stress/tensile strength 0.9, and conductivity 80% IACS.

Further, when the temperature difference between the first time and the final aging is set to within ±25 ° C, the bending workability is improved, and when the first aging temperature is set to be lower than the final aging temperature, heat resistance is obtained. Sexual improvement. From this point of view, inventive Example 5 is inferior in heat resistance since the first aging temperature is lower than the final aging temperature as compared with the other invention examples, and the temperature difference between the first and final aging of Invention Example 7 is 25 Above °C, heat resistance and bending workability are inferior.

On the other hand, in Comparative Examples 1 and 2, the aging temperature was outside the range of 300 to 400 ° C, and in Comparative Example 1 in which the aging temperature was low, the tensile strength was low in Comparative Example 2 in which the electrical conductivity was low and the aging temperature was high.

In Comparative Example 3, the cold rolling degree of the aging was low, and the ratio of the 0.2% proof stress/tensile strength was less than 0.9.

In Comparative Examples 5 and 6, the final cold rolling degree was outside the range of 50 to 80%, and the comparative example 5 having a low workability had a low tensile strength, and the comparative example 6 having a high degree of work had a low electrical conductivity.

Comparative Examples 7 and 8 were produced by one-time aging treatment, and it was difficult to balance the tensile strength, the 0.2% proof stress/tensile strength ratio, or the electrical conductivity.

Comparative Example 9 had a low Zr concentration and a low tensile strength.

In Comparative Example 10, since the concentration of the additive element was 0.1% by mass or more, the electrical conductivity was low.

The comparative example 11 is a copper alloy produced by the same method as that of the first embodiment of the patent document 1 (JP-A-2010-248592). The ratio of tensile strength, 0.2% guaranteed stress/tensile strength is low.

Comparative Examples 12 and 13 are copper alloys produced by the same method as Example 1 and Example 12 of Patent Document 2 (JP-A-2010-242177). In the Cu-Zr alloy of Comparative Example 12, the ratio of tensile strength to 0.2% proof stress/tensile strength was low. On the other hand, although tensile strength was satisfied by adding an additive element as in Comparative Example 13, 550MPa and electrical conductivity 80% IACS, but 0.2% guarantees low stress and 0.2% guarantees low stress/tensile strength ratio.

The comparative example 14 is a copper alloy produced by the same method as that of the fifth embodiment of the patent document 3 (JP-A-2012-172168), and the comparative example 15 is the patent document 4 (Japanese Patent No. 5170916) In the copper alloy produced by the same method as in Invention Example 1-1, the 0.2% guaranteed stress was low, and the 0.2% guaranteed stress/tensile strength ratio was low.

As apparent from the above results, according to the present invention, it is possible to provide a copper alloy strip having high strength, high electrical conductivity, and high bending workability, a high-current electronic component including the copper alloy strip, an electronic component for heat dissipation, and a copper alloy strip. Manufacturing method.

Claims (7)

A copper alloy strip containing 0.04 to 0.5% by mass of Zr, satisfying tensile strength of 550 MPa or more, and 0.2% guaranteed stress/tensile strength 0.9 and the conductivity is 80% IACS or more. For example, the copper alloy strip of the first application patent scope satisfies the 0.2% guaranteed stress after heating at 300 ° C × 30 min. 500MPa. A copper alloy strip according to claim 1, wherein the X-ray diffraction intensity from the {200} plane on the surface of the calendering surface is set to I{200}, and the X-ray diffraction intensity from the {111} plane is obtained. Set to I{111}, when the X-ray diffraction intensity from the {220} plane is set to I{220}, it satisfies 0.1 [I{200}+I{111}+I{311}]/I{220} 0.6. A copper alloy strip according to claim 2, wherein the X-ray diffraction intensity from the {200} plane is set to I{200} on the surface of the calendering surface, and the X-ray diffraction intensity from the {111} plane is obtained. Set to I{111}, when the X-ray diffraction intensity from the {220} plane is set to I{220}, it satisfies 0.1 [I{200}+I{111}+I{311}]/I{220} 0.6. The copper alloy strip according to any one of claims 1 to 4, which contains 0 to 0.1% by mass of an element selected from the group consisting of Ag, Ni, Mn, Mg, Zn, Sn, B, and Ca. At least one. A high-current electronic component having a copper alloy strip according to any one of claims 1 to 5. An electronic component for heat dissipation, comprising the copper alloy strip according to any one of claims 1 to 5.