JP5467163B1 - Copper alloy plate, heat dissipating electronic component comprising the same, and method for producing copper alloy plate - Google Patents

Abstract

A copper alloy having high strength, high conductivity, and excellent workability, a heat dissipating electronic component having the copper alloy, and a method for producing a copper alloy plate are provided.
The copper alloy sheet of the present invention contains 0.01 to 0.5 mass% Fe, and further contains P, and the Fe mass% concentration (% P) with respect to the P mass% concentration (% P). % Fe) ratio (% Fe /% P) is 1.0 to 6.0, the balance is made of copper and inevitable impurities, the conductivity is 65% IACS or more, and the 0.2% proof stress is 400 MPa or more. And 0.2% proof stress σ (MPa) and elongation L (%) satisfy the relationship of σ / L ≦ 150.
[Selection figure] None

Description

  The present invention relates to a copper alloy excellent in heat dissipation, electrical conductivity, drawing workability and bending workability, and more specifically for use in electronic parts such as terminals, connectors, relays, switches, sockets, bus bars, lead frames, especially smartphones and The present invention relates to a copper alloy suitable for heat-dissipating parts and high-current parts used in personal computers.

Parts for obtaining electrical connections such as terminals, connectors, switches, sockets, relays, bus bars, lead frames, and the like are incorporated in electric / electronic devices such as smartphones, tablet PCs, and personal computers.
In recent years, with the miniaturization of smartphones, tablet PCs, and personal computers, heat storage tends to increase when power is supplied to liquid crystal components or IC chips in electric / electronic devices. When the heat storage is large, thermal damage to the IC chip and the substrate is large, and the heat dissipation of the heat dissipation component is a problem.

Conventionally, austenitic stainless steel (SUS304), pure aluminum, and the like have been mainly used for heat dissipation components in electric and electronic devices such as smartphones, tablet PCs, and personal computers. For example, the heat-dissipating parts (liquid crystal frame) attached to the liquid crystal of smartphones and tablet PCs are required to have not only high heat dissipation but also strength as a structure and bending workability or drawing workability necessary for fixing to the liquid crystal. Yes. Further, depending on the heat dissipating component used, only bending workability or drawing workability may be required.
Austenitic stainless steel (SUS304) has good bendability and drawability, but has low thermal conductivity, and an expensive thermal conductive sheet or the like is used in combination to compensate for it. Therefore, the unit price of the heat dissipating component is increased. On the other hand, pure aluminum and aluminum alloys have good bendability and drawability, but lack thermal conductivity and strength as a structure.

  On the other hand, among copper alloys, Cu-Fe-P alloys have a relatively high electrical conductivity, which is known to be proportional to thermal conductivity, and have the required strength and are manufactured at low cost. In particular, for example, JIS alloy number C1921 (Cu-0.1 mass% Fe-0.03 mass% P), C1940 (Cu-2.4 mass% Fe-0.1 mass% P-0.1 mass) % Zn) and the like are put to practical use as heat dissipation parts for the above-mentioned electric and electronic devices. Improvement techniques for Cu—Fe—P alloys are disclosed in, for example, Patent Documents 1 to 5.

JP 2004-099978 A JP 2005-139501 A JP 2005-206871 A JP 2006-083465 A JP 2007-031794 A

  However, although the conventional Cu-Fe-P alloy has high strength and heat conduction characteristics, it does not satisfy the required bendability or drawability, or in some cases.

  Therefore, it can be said that it is industrially significant to improve the bendability and the drawability while maintaining the required high strength and conductivity with the Cu—Fe—P alloy.

  Therefore, the present invention aims to provide a copper alloy plate having high strength and conductivity, and excellent drawing workability and bending workability, a heat dissipating electronic component comprising the same, and a method for producing the copper alloy board. Specifically, it is an object to improve the drawing workability of a Cu—Fe—P-based alloy that is inexpensive and excellent in conductivity and strength.

The present inventor improves drawing workability and bending workability in a Cu-Fe-P alloy by adjusting the metal structure using elongation as an index and controlling the orientation of crystal grains oriented on the rolling surface. I found out. And the following invention was completed against the background of the above knowledge.
The copper alloy sheet of the present invention contains 0.01 to 0.5% by mass of Fe, and further contains P. The mass% concentration of Fe (% Fe) with respect to the mass% concentration (% P) of P The ratio (% Fe /% P) is 1.0 to 6.0, the balance is made of copper and inevitable impurities, the conductivity is 65% IACS or more, and the 0.2% proof stress is 400MPa or more, and 0.2% proof stress σ (MPa) and elongation L (%) satisfy the relationship of σ / L ≦ 150.

In the copper alloy sheet of the present invention, the X-ray diffraction integrated intensity of the {220} plane obtained in the thickness direction on the rolled surface using the X-ray diffraction method is I {220}, and _the pure copper powder standard sample from the {220} plane is used. When the X-ray diffraction integrated intensity is I ⁰ {220}, it is preferable that I {220} / I ⁰ {220} ≧ 4.0.

In the copper alloy sheet of the present invention, the ratio of the minimum bending radius (MBR) in the rolling parallel direction (GW direction) and the rolling perpendicular direction (BW direction) to the sheet thickness (t) in the W bending test is MBR / t. Preferably it is given by ≦ 2.0.
Moreover, in the copper alloy plate of the present invention, it is preferable that the Erichsen value / plate thickness in the Erichsen test is given as 0.5 or more.

In addition, in the copper alloy plate of this invention, it is preferable to further contain 0.5 mass% or less of Sn, and to further contain 1.0 mass% or less of Zn, respectively.
The copper alloy sheet of the present invention preferably further contains at least 0.1 % by mass of one or more elements selected from the group consisting of Ag, Co, Ni, Cr, Mn, Mg, Si and B.

The heat dissipating electronic component of the present invention comprises any one of the above copper alloy plates.
Moreover, in the manufacturing method of the copper alloy plate of the present invention, in manufacturing any of the above copper alloy plates, the ingot is hot-rolled at 800 to 1000 ° C., and then cold rolling and recrystallization annealing are repeated. A method for producing a copper alloy sheet that is subjected to strain relief annealing after the final cold rolling, and in the recrystallization annealing before the final cold rolling, the furnace temperature is set to 350 to 800 ° C. The average crystal grain size is adjusted to 50 μm or less, and in the strain relief annealing, the furnace temperature is set to 300 to 700 ° C., and the copper alloy plate is held in a flat plate shape in the furnace while applying a tension of 5 MPa or less, The 0.2% yield strength is reduced by 10 to 50 MPa.
In this manufacturing method, in the final cold rolling, the total workability is preferably 40 to 99%, and the rolling workability per pass is preferably 15% or more. In the strain relief annealing, a continuous annealing furnace is used. It is preferable to use and pass a copper alloy plate.

  ADVANTAGE OF THE INVENTION According to this invention, it is possible to provide the copper alloy plate which has high intensity | strength, high electroconductivity, and the outstanding drawability, the electronic component for thermal radiation provided with the same, and the manufacturing method of a copper alloy plate. This copper alloy plate can be suitably used as a material for electronic parts such as terminals, connectors, switches, sockets, relays, busbars, lead frames, etc., and is used for heat dissipation and high current parts used in smartphones and personal computers. Suitable for use.

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

(Characteristic)
The copper alloy plate according to an embodiment of the present invention contains 0.01 to 0.5 mass% Fe and P, and the mass% concentration of Fe (% Fe) relative to the mass% concentration (% P) of P. ) Ratio (% Fe /% P) is 1.0 to 6.0, and if necessary, 0.5% by mass or less of Sn, 1.0% by mass or less of Zn is contained, and if necessary A copper alloy containing at least 2% by mass of at least one element selected from the group consisting of Ag, Co, Ni, Cr, Mn, Mg, Si and B, with the balance being composed of copper and inevitable impurities The copper alloy plate has a conductivity of 65% IASC or more, a 0.2% proof stress of 400 MPa or more, and a 0.2% proof stress / elongation (σ / L) of 150 or less. A copper alloy plate having such characteristics is suitable for use as an electronic component for heat dissipation.

(Alloy component concentration)
Fe concentration shall be 0.01-0.5 mass%. When Fe exceeds 0.5 mass%, it becomes difficult to obtain a conductivity of 65% IACS or more. When Fe is less than 0.01% by mass, it becomes difficult to obtain a 0.2% yield strength of 400 MPa or more. For the above reason, the Fe concentration is preferably 0.01 to 0.5% by mass, and more preferably 0.05 to 0.5% by mass.

In addition to Fe, P is added to the copper alloy of the present invention. The ratio (% Fe /% P) of the mass% concentration (% Fe) of Fe to the mass% concentration (% P) of P is adjusted to 1.0 to 6.0, preferably 2.0 to 5.0. . By adjusting% Fe /% P in this way, higher conductivity can be obtained.
More specifically, the P concentration is preferably 0.01 to 0.3% by mass. P has the effect of deoxidizing the molten metal in the alloy manufacturing process. Further, by forming a compound with Fe, there is an effect of increasing the conductivity and strength of the alloy.

0.5 mass% or less of Sn can be added to the Cu-Fe-P alloy of the present invention. Sn has the effect of promoting work hardening of the alloy during rolling and improving the strength of the alloy.
When Sn exceeds 0.5% by mass, the decrease in conductivity is increased. In order to acquire the effect of Sn addition, it is preferable to make the addition amount of Sn 0.001 mass% or more. A more preferable Sn concentration range is 0.005 to 0.3% by mass, and a further preferable Sn concentration range is 0.01 to 0.1% by mass.
In addition, since Sn does not easily form an oxide in molten copper, as long as it is added at a concentration of 0.5% by mass or less, Sn addition does not deteriorate the productivity and quality of the alloy.

  In addition, 1% by mass or less of Zn can be added to the Cu—Fe—P-based alloy of the present invention in order to improve the heat peelability of Sn plating. When Zn exceeds 1 mass%, the fall of electrical conductivity will become large. In order to obtain the effect of adding Zn, the amount of Zn added is preferably 0.001% by mass or more. A more preferable range of Zn concentration is 0.01 to 0.5% by mass. Since it is difficult to form an oxide in molten copper, Zn does not deteriorate the manufacturability and quality of the alloy as long as it is added at a concentration of 1% by mass or less.

  Furthermore, in order to improve strength and heat resistance, the Cu—Fe—P alloy of the present invention includes at least one selected from the group consisting of Ag, Co, Ni, Cr, Mn, Mg, Si and B. It can be included. However, if the amount added is too large, the electrical conductivity decreases or the manufacturability deteriorates. Therefore, the amount added is 2% by mass or less, more preferably 0.5% by mass or less, still more preferably 0.8% by mass. It is limited to 1% by mass or less. Moreover, in order to acquire the effect by addition, it is preferable to make addition amount 0.001 mass% or more in total amount.

(conductivity)
In the present invention, the conductivity measured according to JIS H0505 is set to 65% IACS or more. If the electrical conductivity is 65% IASC or more, the thermal conductivity is good and good heat dissipation can be secured.

(0.2% yield strength)
In the present invention, the 0.2% proof stress of the copper alloy plate is set to 400 MPa or more. According to this, it can be said that the copper alloy plate has a strength necessary as a material for the structural material.

(Elongation)
More preferably, σ / L ≦ 150 so that the relationship of σ / L ≦ 150 is satisfied, where L (%) is the product elongation (El) and σ (MPa) is 0.2% proof stress (YS). By adjusting so as to satisfy the relationship of 100, drawing workability and bendability are improved. If the 0.2% proof stress / elongation is 150 or less, it can be said that the required drawability is obtained. When σ / L> 150, drawability and bendability deteriorate. On the other hand, the lower limit value of σ / L is preferably set to 30, and when σ / L is lower than the lower limit value, the 0.2% proof stress does not satisfy 400 MPa. The upper limit of the elongation L is not particularly limited, but usually when the value exceeds 15%, the strength decreases, and in some cases, the 0.2% proof stress is less than 400 MPa. Therefore, in a preferred embodiment, the elongation L is 15% or less.
“Elongation” here refers to “breaking elongation” as defined in JIS Z2241, and “elongation” and “0.2% proof stress” refer to the rolling direction of the test piece in accordance with JIS Z2241. It shall be measured by a tensile test parallel to the direction.

(Thickness)
The thickness of the product, that is, the plate thickness (t) is preferably 0.05 to 2.0 mm. If the thickness is too small, sufficient heat dissipation cannot be obtained, which is unsuitable as a material for heat dissipation electronic components. On the other hand, if the thickness is too large, drawing and bending become difficult. From such a viewpoint, a more preferable thickness is 0.08 to 1.5 mm. When the thickness is in the above range, it is possible to improve the bending workability while suppressing heat storage.

(Bending workability)
A strip-shaped test piece having a width of 10 mm and a length of 30 mm was prepared and subjected to a W bending test (JIS H3130). The specimen collection direction was a rolling parallel direction (GW) and a rolling perpendicular direction (BW), and evaluation was performed by a ratio MBR / t of a minimum bending radius MBR (Minimum Bend Radius) and a thickness t where no cracks occurred. The ratio (MBR / t) of the minimum bending radius (MBR) is preferably 2.0 or less from the viewpoint of ensuring good bendability. A more preferable range of MBR / t is 1.8 or less.

(Drawing workability)
In the copper alloy plate of the present invention, the ratio of the Erichsen value measured by the Erichsen test based on JIS Z2247 to the plate thickness is preferably 0.5 or more. If the Erichsen value / thickness is 0.5 or more, there is no practical problem as drawing workability. On the other hand, this Erichsen value / plate thickness can be 1.5 or less. This is because if it exceeds 1.5, the 0.2% proof stress may be less than 400 MPa. More preferably, the Erichsen value / plate thickness is in the range of 0.5 to 1.2.

(Crystal orientation)
The X-ray diffraction integrated intensity of the {220} plane obtained in the thickness direction on the rolled surface using the X-ray diffraction method is I {220}, and the X-ray diffraction integrated intensity from the {220} plane of _the pure copper powder standard sample is I ^0. When {220} is set and I {220} / I ⁰ {220} is 4.0 or more, drawing workability is improved. When I {220} / I ⁰ {220} is less than 4.0, since the texture development is small, drawing workability is not improved. Although there is no particular upper limit, I {220} / I ⁰ {220} is more preferably 4.0 to 6.0. The pure copper powder standard sample is defined as a copper powder of 99.5% purity of 325 mesh (JIS Z8801).

  Hereinafter, an example of the suitable manufacturing method of the copper alloy plate which concerns on this invention is demonstrated.

(Production method)
Electro copper or the like is melted as a pure copper raw material, Fe, P and other alloy elements are added as required, and cast into an ingot having a thickness of about 30 to 300 mm. After this ingot is made into a plate having a thickness of about 3 to 30 mm by hot rolling at 800 to 1000 ° C., for example, cold rolling and recrystallization annealing are repeated, and finally finished to a predetermined product thickness by cold rolling. Apply strain relief annealing. The elongation after the final cold rolling is so low that it is less than 2%, but increases by subsequent strain relief annealing.

In recrystallization annealing, part or all of the rolling structure is recrystallized. Further, by annealing under appropriate conditions, Fe or a compound of Fe and P is precipitated, and the electrical conductivity of the alloy is increased.
In the recrystallization annealing before the final cold rolling, the average crystal grain size of the copper alloy sheet is adjusted to 50 μm or less. If the average crystal grain size is too large, it will be difficult to adjust the 0.2% yield strength to 400 MPa or more.

  The conditions for recrystallization annealing before the final cold rolling are determined based on the target crystal grain size after annealing and the target product conductivity. Specifically, annealing may be performed by using a batch furnace or a continuous annealing furnace and setting the furnace temperature to 350 to 800 ° C. In a batch furnace, the heating time may be appropriately adjusted at a temperature in the furnace of 350 to 600 ° C. in the range of 30 minutes to 30 hours. In a continuous annealing furnace, the heating time may be appropriately adjusted within a range of 5 seconds to 10 minutes at a furnace temperature of 450 to 800 ° C. Generally, when annealing is performed at a lower temperature for a longer time, higher conductivity can be obtained with the same crystal grain size.

In the final cold rolling, the material is repeatedly passed between a pair of rolling rolls to finish the target plate thickness. Here, the total workability of final cold rolling and the workability per pass are controlled.
The total workability R (%) is given by R = (t ₀ −t) / t ₀ × 100 (t ₀ : plate thickness before final cold rolling, t: plate thickness after final cold rolling). Further, the processing degree r (%) per pass is a sheet thickness reduction rate when the rolling roll passes once, and r = (T ₀ −T) / T ₀ × 100 (T ₀ : rolling roll) Thickness before passing, T: Thickness after passing the rolling roll).

The total processing degree R is 40 to 99%, preferably 45 to 98.5, and more preferably 50 to 98. If the total workability R is too small, it is difficult to adjust the 0.2% proof stress to 400 MPa or more, and it becomes difficult to adjust I {220} / I ⁰ {220} to 4.0 or more. If the total workability R is too large, the edge of the rolled material may be broken.
The degree of processing r per pass is 15% or more. If the degree of processing r is too small, I {220} / I ⁰ {220} decreases, and if any path with a degree of processing r of less than 15% is included in all the paths, I {220} / I ⁰ { 220} becomes difficult to adjust to 4.0 or more. There is no particular upper limit on the working degree r, but it is preferably less than 40% in consideration of control of the thickness tolerance by rolling.

  The strain relief annealing of the present invention is performed using a continuous annealing furnace capable of holding a copper alloy plate in a flat plate shape in the furnace. In the case of a batch furnace, the material is heated in a coiled state, so that the material undergoes plastic deformation during the heating, and the material is warped. Therefore, the batch furnace is not suitable for the strain relief annealing of the present invention.

In a continuous annealing furnace, the furnace temperature is set to 300 to 700 ° C., preferably 350 to 650 ° C., the heating time is appropriately adjusted in the range of 5 seconds to 10 minutes, and 0.2% yield strength (σ) after strain relief annealing. Is adjusted to a value 10 to 50 MPa lower, preferably 15 to 45 MPa lower than the 0.2% proof stress (σ ₀ ) before strain relief annealing. As a result, the elongation which was low after the final cold rolling is increased and the bendability is improved.

  Further, in the continuous annealing furnace, tension is applied to the material, for example, in a direction parallel to the rolling direction, and the tension applied here is adjusted to 5 MPa or less, preferably 1 to 5 MPa, more preferably 2 to 4 MPa. If the tension is too large, it is difficult to adjust σ / L to 150 or less. Further, the increase in elongation tends to be insufficient. On the other hand, if the tension is too small, the material in the passing plate of the annealing furnace may come into contact with the furnace wall, and the surface or edge of the material may be damaged.

One embodiment of the present invention provides a drawability by imparting a feature of σ / L ≦ 150 and a feature of I {220} / I ⁰ {220} ≧ 4.0 to a Cu—Fe—P based alloy. One of the features is to improve the bending workability.
(1) For σ / L ≦ 150,
a. In the strain relief annealing, (σ ₀ −σ) = 10 to 50 MPa is adjusted.
b. The furnace tension in the strain relief annealing is adjusted to 5 MPa or less.
(2) For I {220} / I ⁰ {220} ≧ 4.0,
a. In the final cold rolling, the processing degree per pass is adjusted to 15% or more.
b. The total working degree of the final cold rolling is set to 40 to 99%.

  The copper alloy plate manufactured as described above is processed into a copper product having various plate thicknesses, and is used as, for example, an electronic component for heat dissipation in an electric / electronic device such as a smartphone, a tablet PC, and a personal computer. Can do.

Examples of the present invention are shown below, but these examples are provided for better understanding of the present invention and its advantages, and are not intended to limit the invention.
After adding the alloy element to the molten copper, it was cast into an ingot having a thickness of 200 mm. 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. After grinding and removing the oxide scale on the surface of the hot rolled plate with a grinder, annealing and cold rolling were repeated, and the product was finished to a predetermined product thickness by final cold rolling. Finally, strain relief annealing was performed using a continuous annealing furnace.

  Annealing before final cold rolling (final recrystallization annealing) uses a batch furnace, adjusts the furnace temperature in the range of 300 to 700 ° C. with a heating time of 5 hours, and sets the crystal grain size and conductivity after annealing. Changed. In the measurement of the crystal grain size after annealing, a cross section perpendicular to the rolling direction was subjected to chemical corrosion after mirror polishing, and the average crystal grain size was determined by a cutting method (JIS H0501 (1999)).

In the final cold rolling, the total workability and the workability per pass were controlled. Moreover, the 0.2% yield strength of the material after final cold rolling was calculated | required.
In strain relief annealing using a continuous annealing furnace, the furnace temperature was 500 ° C., the heating time was adjusted between 1 second and 15 minutes, and the 0.2% proof stress after annealing was variously changed. In addition, various tensions were added to the material in the furnace. For some materials, strain relief annealing was omitted.
The following measurement was performed on the material in the process of manufacturing and the material after strain relief annealing.

(component)
The alloy element concentration of the material after strain relief annealing was analyzed by ICP-mass spectrometry.

(0.2% yield strength)
For the material after the final cold rolling and strain relief annealing, sample No. 13B specified in JIS Z2241 was taken so that the tensile direction was parallel to the rolling direction, and pulled in parallel with the rolling direction in accordance with JIS Z2241. Tests were performed to determine 0.2% yield strength.

  The main conditions described above are shown in Table 1 for each invention example and comparative example. Here, a plurality of passes were carried out in the final cold rolling, but the minimum value in the degree of processing of each of these passes is shown. Moreover, in the place shown in Table 1, the notation of “<10 μm” in the crystal grain size after the final recrystallization annealing indicates that all of the rolled structure was recrystallized and the average crystal grain size was less than 10 μm, and the rolling It includes both cases where only a part of the structure is recrystallized.

(Elongation)
With respect to the material after strain relief annealing thus obtained, a No. 13B test piece defined in JIS Z2241 was taken so that the tensile direction was parallel to the rolling direction, and the elongation was measured with a distance between the gauge points of 50 mm.

(conductivity)
A test piece was taken from the material after strain relief annealing so that the longitudinal direction of the test piece was parallel to the rolling direction, and the conductivity at 20 ° C. was measured by a four-terminal method in accordance with JIS H0505.

(Crystal orientation)
The X-ray diffraction integrated intensity of the {220} plane was measured in the thickness direction with respect to the surface of the material after strain relief annealing. Similarly, the X-ray diffraction integrated intensity of the {220} plane was measured for a pure copper powder standard sample. RINT 2500 manufactured by Rigaku Corporation was used as the X-ray diffractometer, and measurement was performed with a Cu tube bulb at a tube voltage of 25 kV and a tube current of 20 mA.

(Erichsen value)
The material after strain relief annealing was tested using an Erichsen testing machine under the conditions of sample shape Φ90 mm, lubricant: grease, punch pushing speed 5 mm / min, and the Erichsen value was determined. Table 2 shows the evaluation results.

(MBR / t)
In accordance with JIS H3130, a W-shaped test is performed in each of the GW (Goodway) direction in which the bending axis is perpendicular to the rolling direction and the BW (Badway) direction in which the bending axis is the same as the rolling direction. The bending radius was changed using the mold of the mold, and the ratio (MBR / t) of the minimum bending radius (MBR) and thickness (t) at which no crack occurred was obtained.

As can be seen from Tables 1 and 2, in Invention Examples 1 to 22 , the Fe concentration is 0.01 to 0.5% by mass, and the ratio of Fe concentration to P concentration (% Fe /% P) is 1. 0 to 6.0, the crystal grain size is adjusted to 50 μm or less in the recrystallization annealing before the final cold rolling, the total workability is adjusted to 40 to 99% in the final cold rolling, and the distortion is removed. In the annealing, the material was passed through a continuous annealing furnace with a tension of 1 to 5 MPa to reduce the 0.2% proof stress by 10 to 50 MPa. Thereby, the copper alloy plates of Invention Examples 1 to 22 have a relationship of σ / L ≦ 150, conductivity of 65% IACS or higher, 0.2% proof stress of 400 MPa or higher, MBR / t ≦ 2.0. W bendability could be achieved. In Invention Examples 5 and 9, since the degree of processing per pass in the final cold rolling was less than 15%, I {220} / I ⁰ {220} was 4. 0 becomes less than, Although Erichsen value / thickness is less than 5, the invention examples 1～4,6～8,10～ 22 the working ratio per pass was 15% or more, I { 220} / I ⁰ {220} ≧ 4.0 and Erichsen value / plate thickness ≧ 0.5.

On the other hand, Comparative Example 1 was not subjected to strain relief annealing, σ / L exceeded 200, and the bendability and drawability were poor.
In Comparative Examples 2 and 3, strain relief annealing was performed, but since the material tension in the furnace exceeded 5 MPa, σ / L was 150 or more, and in Comparative Example 3 in which the tension was particularly high, σ / L was 200. Thus, the bendability and drawability of Comparative Examples 2 and 3 were poor.
In Comparative Example 4, the amount of decrease in 0.2% proof stress in strain relief annealing was too small, and (σ ₀ −σ) deviated from the range of 10 to 50 MPa. For this reason, σ / L exceeded 150, and drawability and bendability were poor.
In Comparative Example 5, since the strength reduction during strain relief annealing was large, the 0.2% proof stress after strain relief annealing was less than 400 MPa.

In Comparative Example 6, since the Fe concentration was less than 0.01% by mass, the 0.2% proof stress after strain relief annealing was less than 400 MPa.
In Comparative Example 7, since the Fe concentration exceeded 0.5 mass%, in Comparative Examples 8 and 9, since% Fe /% P was out of the range of 1.0 to 6.0, the conductivity was less than 65% IACS. It was.

  In Comparative Example 10, the crystal grain size after the recrystallization annealing before the final cold rolling exceeded 50 μm, and in Comparative Example 11, the total degree of work in the final cold rolling was less than 40%. The 2% proof stress was less than 400 MPa.

  From the above results, according to the present invention, a copper alloy plate having high strength and conductivity, and excellent drawing workability and bending workability, a heat dissipating electronic component comprising the same, and a method for producing a copper alloy plate are provided. It is clear that it can be provided.

Claims (11)

  The ratio of the mass% concentration (% Fe) of Fe to the mass% concentration (% P) of P containing 0.01 to 0.5% by mass of Fe and further containing P (% Fe /% P) 1.0 to 6.0, with the balance being copper and inevitable impurities, having a conductivity of 65% IACS or higher, a 0.2% proof stress of 400 MPa or higher, and a 0.2% proof stress σ ( (MPa) and elongation L (%) satisfy | fill the relationship of (sigma) / L <= 150. The X-ray diffraction integrated intensity of the {220} plane obtained in the thickness direction on the rolled surface using the X-ray diffraction method is I {220}, and the X-ray diffraction integrated intensity from the {220} plane of _the pure copper powder standard sample is I ^0. 2. The copper alloy sheet according to claim 1, wherein {220} is I {220} / I ⁰ {220} ≧ 4.0.   The ratio of the minimum bending radius (MBR) in the rolling parallel direction (GW direction) and the perpendicular direction (BW direction) in the W bending test to the sheet thickness (t) is given by MBR / t ≦ 2.0. Or the copper alloy plate of 2.   The copper alloy sheet according to any one of claims 1 to 3, wherein an Erichsen value / plate thickness in the Eriksen test is 0.5 or more.   The copper alloy plate according to any one of claims 1 to 4, further containing 0.5 mass% or less of Sn.   The copper alloy plate according to any one of claims 1 to 5, further containing 1.0% by mass or less of Zn. The copper according to any one of claims 1 to 6, further containing at least 0.1 % by mass of one or more elements selected from the group consisting of Ag, Co, Ni, Cr, Mn, Mg, Si and B. Alloy plate.   A heat dissipating electronic component comprising the copper alloy plate according to claim 1. In producing the copper alloy sheet according to any one of claims 1 to 7, after ingot is hot-rolled at 800 to 1000 ° C, cold rolling and recrystallization annealing are repeated, and the final cold A method for producing a copper alloy sheet that is subjected to strain relief annealing after rolling,
In the recrystallization annealing before the final cold rolling, the furnace temperature is set to 350 to 800 ° C., and the average crystal grain size of the copper alloy plate is adjusted to 50 μm or less,
In the strain relief annealing, the furnace temperature is set to 300 to 700 ° C., and the 0.2% proof stress is reduced by 10 to 50 MPa while applying a tension of 5 MPa or less with the copper alloy plate held in a flat plate shape in the furnace. The manufacturing method of a copper alloy plate.   The method for producing a copper alloy sheet according to claim 9, wherein in the final cold rolling, the total workability is 40 to 99%, and the roll workability per pass is 15% or more.   The manufacturing method of the copper alloy plate of Claim 9 or 10 which passes a copper alloy plate using the continuous annealing furnace in the said strain relief annealing.