JP6196757B2 - Corson alloy and manufacturing method thereof - Google Patents

Description

  The present invention is excellent in strength, bending workability, stress relaxation suitable as a lead frame material for semiconductor devices such as conductive spring materials such as connectors, terminals, relays and switches, and transistors and integrated circuits (ICs). The present invention relates to a Corson alloy having characteristics, conductivity, and the like, and a manufacturing method thereof.

  In recent years, electrical and electronic parts have been miniaturized, and copper alloys used for these parts are required to have good strength, electrical conductivity, and bending workability. In response to this demand, demand for precipitation strengthened copper alloys such as Corson alloys having high strength and conductivity is increasing instead of conventional solid solution strengthened copper alloys such as phosphor bronze and brass. A Corson alloy is an alloy in which an intermetallic compound such as Ni—Si, Co—Si, or Ni—Co—Si is precipitated in a Cu matrix, and has high strength, high electrical conductivity, and good bending workability. Generally, strength and bending workability are contradictory properties, and it is desired to improve bending workability while maintaining high strength even in a Corson alloy.

  Here, in the Corson alloy, the bending workability when the bending axis is perpendicular to the rolling direction (Good Way) is inferior to the bending workability when the bending axis is parallel to the rolling direction (Bad Way). There is a particular need for improving the good workability of Good Way.

  In recent years, as a technique for improving the bending workability of the Corson alloy, a strategy for developing the {001} <100> orientation (Cube orientation) has been proposed. For example, in patent document 1 (Unexamined-Japanese-Patent No. 2006-283059), (1) Casting, (2) Hot rolling, (3) Cold rolling (working degree 95% or more), (4) Solution treatment, (5 Cube orientation by performing the steps of cold rolling (working degree 20% or less), (6) aging treatment, (7) cold rolling (working degree 1-20%), and (8) short-time annealing. Is controlled to 50% or more to improve the bending workability.

  In Patent Document 2 (Japanese Patent Laid-Open No. 2010-275622), (1) casting, (2) hot rolling (performed while lowering the temperature from 950 ° C to 400 ° C), (3) cold rolling (working degree of 50% or more) ), (4) Intermediate annealing (450 to 600 ° C., adjusting conductivity to 1.5 times or more and hardness to 0.8 times or less), (5) cold rolling (working degree 70% or more), ( 6) Solution treatment, (7) Cold rolling (working degree 0 to 50%), (8) Aging treatment is carried out in order, and the X-ray diffraction intensity of (200) (synonymous with {001}) is reduced to copper powder. Bending workability is improved by controlling the X-ray diffraction intensity of the standard sample.

  In Patent Document 3 (Japanese Patent Laid-Open No. 2011-17072), the area ratio of the Cube orientation is controlled to 5 to 60%, and at the same time, the area ratios of the Brass orientation and Copper orientation are both controlled to 20% or less to improve bending workability. doing. Production methods for this purpose include (1) casting, (2) hot rolling, (3) cold rolling (working degree 85 to 99%), and (4) heat treatment (300 to 700 ° C, 5 minutes to 20 hours). (5) Cold rolling (working degree 5 to 35%), (6) Solution treatment (temperature increase rate 2 to 50 ° C./second), (7) Aging treatment, (8) Cold rolling (working degree 2) ~ 30%) and (9) temper annealing are performed in order to obtain the best bendability.

  In Patent Document 4 (Japanese Patent No. 4857395), the area ratio of the Cube orientation is controlled to 10 to 80% at the center in the thickness direction, and at the same time, the area ratios of the Brass orientation and Copper orientation are both controlled to 20% or less. And notch bendability is improved. Manufacturing methods that enable notch bending include (1) casting, (2) hot rolling, (3) cold rolling (30 to 99%), and (4) pre-annealing (softening degree of 0.25 to 0.75). , Conductivity 20-45% IACS), (5) cold rolling (7-50%), (6) solution treatment, (7) aging.

  In Patent Document 5 (WO2011 / 068121), the Cube azimuth area ratios at 1/4 positions of the entire surface layer and depth position of the material are W0 and W4, respectively, and W0 / W4 is 0.8 to 1.5. , W0 is controlled to 5 to 48%, and the average crystal grain size is adjusted to 12 to 100 μm, thereby improving 180-degree adhesion bendability and stress relaxation resistance. Production methods therefor include (1) casting, (2) hot rolling, (the processing rate of one pass is 30% or less and the holding time between each pass is 20 to 100 seconds), (3) cold rolling (Working degree 90 to 99%), (4) heat treatment (300 to 700 ° C., 10 seconds to 5 hours), (5) cold rolling (working degree 5 to 50%), (6) solution treatment (800 to 1000 ° C), (7) aging treatment, (8) cold rolling, and (9) temper annealing are proposed.

  Although it is not a technique for improving bendability, in Patent Document 6 (WO2011 / 068134), the Young's modulus is bent to 110 GPa or less by controlling the area ratio of the (100) plane facing the rolling direction to 30% or more. The coefficient is adjusted to 105 GPa or less. As manufacturing methods therefor, (1) casting, (2) hot rolling (slow cooling), (3) cold rolling (working degree of 70% or more), (4) heat treatment (300 to 800 ° C., 5 seconds) ~ 2 hours), (5) cold rolling (working degree 3 to 60%), (6) solution treatment, (7) aging treatment, (8) cold rolling (working degree 50% or less), (9) The process of temper annealing is proposed.

JP 2006-283059 A JP 2010-275622 A JP 2011-17072 A Japanese Patent No. 4857395 WO2011 / 068121 WO2011 / 068134

  This inventor examined the spring characteristic after processing a connector about the Corson alloy which developed Cube orientation and improved bendability according to the prior art. As a result, as schematically shown in FIG. 1, when used as an end face contact type terminal in which the spring portion is taken in a direction orthogonal to the rolling direction (hereinafter referred to as the rolling orthogonal direction), the spring contact is sufficient. The contact force could not be obtained, and the contact electrical resistance sometimes increased. It was also found that this decrease in contact force is related to a low Young's modulus in the direction perpendicular to rolling. The Young's modulus here refers to the Young's modulus obtained from a stress-strain curve obtained by conducting a tensile test in the direction perpendicular to the rolling direction, and obtained from the slope of the straight line of the elastic range in the stress-strain curve. The copper standard association (JACBA) technical standard “Method of measuring bending deflection coefficient by cantilever of copper and copper alloy strips”) showed no correlation with the contact force. Hereinafter, the simple expression “Young's modulus” refers to the Young's modulus obtained from a tensile test.

  Then, this invention makes it a subject to provide the Corson alloy which has the high Young's modulus of a rolling orthogonal direction, and its manufacturing method while having the outstanding bending workability.

  The present inventor analyzed the crystal orientation of the Corson alloy by the EBSD method, and optimized the crystal orientation for each of the surface and the cross-section at the center of the plate thickness, so that the bendability is good, but the orthogonal direction of rolling It was found that a Corson alloy having a sufficiently high Young's modulus can be obtained, and a manufacturing method for obtaining this crystal orientation was clarified.

The present invention completed on the basis of the above knowledge, in one aspect, contains 0.8 to 5.0 mass% of one or more of Ni and Co, 0.2 to 1.5 mass% of Si, and the balance is copper. And an area ratio of a Cube orientation {001} <100> that is an area ratio of a region having an orientation within 10 ° from the Cube orientation on the surface of the rolled material is 5 to 80%. Yes, in a cross section having a depth of 45 to 55% with respect to the plate thickness, the <100> direction which is the area ratio of the region where the angle formed by the <100> direction and TD is within 10 ° is the width direction of the rolled material (TD ) Is a Corson alloy having an area ratio of crystals oriented to 50% or less.

  In one embodiment of the Corson alloy according to the present invention, a total amount of one or more of Sn, Zn, Mg, Fe, Ti, Zr, Cr, Al, P, Mn, and Ag is 0.005 to 3.0 mass. %contains.

  In another embodiment of the Corson alloy according to the present invention, the Young's modulus obtained from a tensile test in a direction orthogonal to the rolling direction is 106 GPa or more.

  In yet another embodiment of the Corson alloy according to the present invention, it is used as a material for an end face contact type terminal sampled in a direction orthogonal to the rolling direction.

In another aspect of the present invention, at least one of Ni and Co is contained in an amount of 0.8 to 5.0 mass%, Si is contained in an amount of 0.2 to 1.5 mass%, and the balance is made of copper and inevitable impurities. An ingot was produced, the ingot was hot-rolled from a temperature of 800 to 1000 ° C. to a thickness of 3 to 20 mm, and cold rolling with a workability of 90 to 99.8% was performed. After setting the values to 20% or less and 15% or less, respectively, pre-annealing with a softening degree of 0.20 to 0.80, cold rolling with a working degree of 3 to 50%, and a solution at 700 to 950 ° C. for 5 to 300 seconds. Is a method of sequentially performing a chemical treatment, cold rolling at a working degree of 0 to 60%, an aging treatment at 350 to 600 ° C. for 2 to 20 hours, and a cold rolling at a working degree of 0 to 50%.
The softening degree is defined as S,
S = (σ ₀ −σ) / (σ ₀ −σ ₉₅₀ )
It is a manufacturing method of the Corson alloy based on this invention shown by these.
Here, σ ₀ is the tensile strength before pre-annealing, and σ and σ ₉₅₀ are the tensile strength after pre-annealing and after annealing at 950 ° C., respectively.

  In one embodiment of the method for producing a Corson alloy according to the present invention, the ingot contains one or more of Sn, Zn, Mg, Fe, Ti, Zr, Cr, Al, P, Mn, and Ag in a total amount of 0. 0.005 to 3.0 mass%.

  In yet another aspect, the present invention is a copper-stretched product provided with the Corson alloy of the present invention.

  In still another aspect, the present invention is an electronic device component including the Corson alloy of the present invention.

  ADVANTAGE OF THE INVENTION According to this invention, the Corson alloy which has the outstanding bending workability and the high Young's modulus of a rolling orthogonal direction, and its manufacturing method can be provided.

It is a schematic diagram for demonstrating the end surface contact type | mold terminal extract | collected in a rolling orthogonal direction. It is a graph which shows the relationship between the annealing temperature when the alloy which concerns on this invention is annealed at various temperatures, and tensile strength.

(Addition amount of Ni, Co and Si)
Ni, Co, and Si are precipitated as intermetallic compounds such as Ni—Si, Co—Si, and Ni—Co—Si by performing an appropriate aging treatment. The strength of the precipitate is improved by the action of the precipitate, and Ni, Co, and Si dissolved in the Cu matrix are reduced by the precipitation, so that the conductivity is improved. However, when the total amount of Ni and Co is less than 0.8% by mass or Si is less than 0.2% by mass, the desired strength cannot be obtained. Conversely, the total amount of Ni and Co exceeds 5.0% by mass. When Si exceeds 1.5% by mass, the bending workability is remarkably deteriorated. For this reason, in the Corson alloy which concerns on this invention, the addition amount of 1 or more types is set to 0.8-5.0 mass% among Si and Ni, and the addition amount of Si is 0.2-1.5 mass%. The addition amount of one or more of Ni and Co is more preferably 1.0 to 4.0% by mass, and the addition amount of Si is more preferably 0.25 to 0.90% by mass.

(Other additive elements)
Sn, Zn, Mg, Fe, Ti, Zr, Cr, Al, P, Mn, and Ag contribute to an increase in strength. Furthermore, Zn is effective in improving the heat-resistant peelability of Sn plating, Mg is effective in improving stress relaxation characteristics, and Zr, Cr, and Mn are effective in improving hot workability. If the total amount of Sn, Zn, Mg, Fe, Ti, Zr, Cr, Al, P, Mn, and Ag is less than 0.005% by mass, the above effect cannot be obtained. Workability is significantly reduced. For this reason, in the Corson alloy which concerns on this invention, it is preferable to contain 0.005-3.0 mass% of these elements in a total amount, and it is more preferable to contain 0.01-2.5 mass%.

(Young's modulus)
In the end face contact type terminal where the spring part is orthogonal to the rolling direction, in order to obtain a sufficient contact force at the spring contact, it is preferable to adjust the Young's modulus in the rolling orthogonal direction to 106 GPa or more, and to 111 GPa or more. More preferred.
Although the upper limit of the Young's modulus is not restricted in terms of contact force, the Young's modulus of the Corson alloy of the present invention is typically 130 GPa or less, more typically 120 GPa or less.
The Young's modulus of the invention alloy is also evaluated in Patent Documents 4 and 5, but the Young's modulus of Document 4 is a bending deflection coefficient measured in parallel with the rolling direction. Although the Young's modulus is obtained by this, the tensile test is performed in parallel with the rolling direction.

(Crystal orientation)
In the present invention, the crystal orientation is adjusted based on a measurement value by EBSD (Electron Back Scatter Diffraction). Here, EBSD is a technique for analyzing crystal orientation using reflected electron Kikuchi line diffraction (Kikuchi pattern) generated when a sample is irradiated with an electron beam in a SEM (Scanning Electron Microscope). . The electron beam is irradiated onto the sample surface, and information obtained at this time is orientation information up to a depth of several tens of nanometers in which the electron beam penetrates, that is, orientation information of the polar surface layer.
In the rolled material of the Corson alloy, when the area ratio of crystals oriented in the Cube orientation on the surface (hereinafter referred to as Cube orientation area ratio) increases, non-uniform deformation is suppressed and bending workability is improved. Here, the Cube orientation is a state in which the (001) plane faces the rolling surface normal direction (ND) and the (100) plane faces the rolling direction (RD), and is an index of {001} <100>. Indicated. Therefore, in order to obtain good bending workability, the Cube orientation area ratio on the surface is controlled to 5% or more, preferably 10% or more, and more preferably 20% or more.
Although the upper limit of the Cube orientation area ratio is not restricted from the viewpoint of improving the bending workability, the Cube orientation area ratio of the Corson alloy of the present invention is typically 80% or less.
In the case of a conventional Corson alloy in which the Cube orientation area ratio on the surface is increased to improve the bending workability, the Young's modulus in the direction perpendicular to the rolling is less than 106 GPa. In order to increase the Young's modulus, the crystal orientation at the center of the plate thickness is adjusted based on the measured value by EBSD. Here, the crystal orientation of the central portion of the plate thickness is determined by etching the sample from one surface of the sample by etching, mechanical polishing, etc. to expose the cross section of the central portion of the plate thickness and performing EBSB measurement on this cross section. Measure with A plate | board thickness center part points out the position of 45 to 55% with respect to plate | board thickness.
When the area ratio of the crystals in which the <100> direction is oriented in the width direction (TD) of the rolled material is controlled to 50% or less in the center portion of the plate thickness, the Young's modulus in the direction perpendicular to the rolling becomes 106 GPa or more. As a crystal in which the <100> direction is oriented in the width direction (TD) of the rolled material, in addition to the Cube orientation, the Cube orientation is an orientation rotated about TD (for example, {011} <011>, {012} <021 > Etc.).
Although the lower limit value of the area ratio of the crystal in which the <100> direction in the central portion of the plate thickness is oriented in the width direction (TD) of the rolled material is not restricted in terms of increasing the Young's modulus in the direction perpendicular to the rolling direction, the Corson alloy of the present invention The total value of is typically 5% or more.

(Production method)
In a general manufacturing process of a Corson alloy, first, raw materials such as electrolytic copper, Ni, Co, and Si are melted in a melting furnace to obtain a molten metal having a desired composition. Then, this molten metal is cast into an ingot. Thereafter, the strips and foils having desired thickness and characteristics are finished in the order of hot rolling, cold rolling, solution treatment, and aging treatment. After the heat treatment, surface pickling, polishing, or the like may be performed in order to remove the surface oxide film generated during the heat treatment. In order to increase the strength, cold rolling may be performed between the solution treatment and aging or after aging.
In the present invention, in order to obtain the above crystal orientation, before the solution treatment, heat treatment (hereinafter also referred to as pre-annealing) and relatively low work cold rolling (hereinafter also referred to as light rolling), Furthermore, conditions for cold rolling between hot rolling and pre-annealing are adjusted.
The preliminary annealing is performed for the purpose of partially generating recrystallized grains in a rolled structure formed by cold rolling after hot rolling. There is an optimum value for the ratio of recrystallized grains in the rolled structure, and the above-mentioned crystal orientation cannot be obtained if the amount is too small or too large. The optimum proportion of recrystallized grains can be obtained by adjusting the pre-annealing conditions so that the softening degree S defined below is 0.20 to 0.80, more preferably 0.25 to 0.75.
FIG. 2 illustrates the relationship between the annealing temperature and the tensile strength when the alloy according to the present invention is annealed at various temperatures. A sample with a thermocouple attached was inserted into a 1000 ° C. tubular furnace, and when the sample temperature measured by the thermocouple reached a predetermined temperature, the sample was taken out of the furnace, cooled with water, and the tensile strength was measured. is there. Recrystallization proceeds when the sample arrival temperature is 500 to 700 ° C., and the tensile strength is drastically decreased. The gradual decrease in tensile strength on the high temperature side is due to the growth of recrystallized grains.

The softening degree S in the pre-annealing is defined by the following equation.
S = (σ ₀ −σ) / (σ ₀ −σ ₉₅₀ )
Here, σ ₀ is the tensile strength before annealing, and σ and σ ₉₅₀ are the tensile strength after preliminary annealing and after annealing at 950 ° C., respectively. The temperature of 950 ° C. is adopted as a reference temperature for knowing the tensile strength after recrystallization because the alloy according to the present invention is stably completely recrystallized when annealed at 950 ° C.
If the softening degree is out of the range of 0.2 to 0.8, the area ratio of the Cube orientation is less than 5% on the surface of the rolled material. The temperature and time of the pre-annealing are not particularly limited, and it is important to adjust S to the above range. Generally, when a continuous annealing furnace is used, the furnace temperature ranges from 400 to 750 ° C. for 5 seconds to 10 minutes, and when a batch annealing furnace is used, the furnace temperature ranges from 350 to 600 ° C. for 30 minutes to 20 hours. Done in
The pre-annealing conditions can be set by the following procedure.
(1) Measure the tensile strength (σ ₀ ) of the material before pre-annealing.
(2) The material before preliminary annealing is annealed at 950 ° C. Specifically, the material to which the thermocouple is attached is inserted into a 1000 ° C. tubular furnace, and when the sample temperature measured by the thermocouple reaches 950 ° C., the sample is taken out of the furnace and water-cooled.
(3) Obtain the tensile strength (σ ₉₅₀ ) of the material after annealing at 950 ° C.
(4) For example, when σ ₀ is 800 MPa and σ ₉₅₀ is 300 MPa, the tensile strengths corresponding to the softening degrees of 0.20 and 0.80 are 700 MPa and 400 MPa, respectively.
(5) Pre-annealing conditions are determined so that the tensile strength after annealing is 400 to 700 MPa.

After the pre-annealing, prior to the solution treatment, light rolling with a workability of 3 to 50%, more preferably 7 to 50% is performed. The processing degree R (%) is defined by the following equation.
R = (t ₀ −t) / t ₀ × 100 (t ₀ : plate thickness before rolling, t: plate thickness after rolling)
When the workability is out of the range of 3 to 50%, the area ratio of the Cube orientation on the rolled material surface becomes less than 5%.
In addition to the pre-annealing and the light rolling, by adjusting the conditions of the cold rolling between the hot rolling and the pre-annealing, the area ratio of the Cube orientation is 5% or more on the surface, The crystal orientation characteristic in which the area ratio of crystals whose <100> direction is oriented to the TD of the rolled material is 50% or less can be imparted.
In the cold rolling, the material is repeatedly passed between a pair of rolling rolls to finish the target plate thickness. The crystal orientation is affected by the total degree of work in cold rolling and the degree of work per pass. Here, the total working degree R indicates a working degree in general and is defined by the same formula as R described above. 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 90 to 99.8%. When R is less than 90%, the area ratio of the Cube orientation on the surface is less than 5%. If R exceeds 99.8%, cracks may occur at the edges of the rolled material, and the material being rolled may break. A more preferable degree of processing is 95 to 99%.
Regarding the processing degree r per pass, the maximum value (r _max ) of all passes is set to 20% or less, and the average value (r _ave ) of all passes is set to 15% or less. If it deviates from this condition, the area ratio of the crystal in which the <100> direction is oriented to the TD of the rolled material in the central portion of the plate thickness exceeds 50%. The lower limit of r _ave, but are not limited in terms of crystal orientation, since the time rolling and r _ave becomes smaller consuming production efficiency decreases, r _ave is preferably set to 10% or more.

It is as follows when the manufacturing method of this invention alloy is listed in order of a process.
(1) Ingot casting (thickness 20 to 300 mm)
(2) Hot rolling (temperature 800 to 1000 ° C., thickness 3 to 20 mm)
(3) Cold rolling (R = 90-99.8%, r _max ≦ 20%, r _ave ≦ 15%)
(4) Pre-annealing (degree of softening: S = 0.20 to 0.80)
(5) Light rolling (working degree 3-50%)
(6) Solution treatment (700 to 950 ° C. for 5 to 300 seconds)
(7) Cold rolling (working degree 0-60%)
(8) Aging treatment (2 to 20 hours at 350 to 600 ° C.)
(9) Cold rolling (working degree 0-50%)
(10) Strain relief annealing (at 300 to 700 ° C. for 5 seconds to 10 hours)

Cold rolling (7) and (9) is optionally performed to increase the strength. However, while the strength increases as the rolling degree increases, the area ratio of the Cube orientation on the surface tends to decrease. If the respective working degrees in the cold rolling (7) and (9) exceed the upper limit, the area ratio of the Cube orientation on the surface becomes less than 5% and the bending workability deteriorates.
The strain relief annealing (10) is optionally performed in order to recover the spring limit value and the like which are lowered by the cold rolling when the cold rolling (9) is performed. Regardless of the presence or absence of strain relief annealing (10), the effect of the present invention that both good bending workability and high Young's modulus in the orthogonal direction of rolling can be achieved by controlling the crystal orientation. The strain relief annealing (10) may or may not be performed.
In addition, what is necessary is just to select the general manufacturing conditions of a Corson alloy about process (2), (6) and (8).

  The Corson alloy of the present invention can be processed into various copper products, for example, plates, strips and foils. Further, the Corson alloy of the present invention is a lead frame, connector, pin, terminal, relay, switch, secondary battery. It can be used for electronic device parts such as foil materials. In particular, it is suitable as a part to be subjected to severe Good Way bending, and a part (see FIG. 1) in which a spring part is taken in a direction perpendicular to rolling to obtain an electrical contact by end face contact. The direction orthogonal here refers to the case where the angle formed by the rolling direction and the spring portion direction is 60 to 120 degrees. If the said angle is 70-110 degree | times, the effect of invention will be exhibited more, and if it is 80-100 degree | times, the effect of invention will be exhibited more fully.

  Examples of the present invention will be described below together with comparative examples, but these examples are provided for better understanding of the present invention and its advantages, and are not intended to limit the invention.

Example 1
An alloy containing Ni: 2.6% by mass, Si: 0.58% by mass, Sn: 0.5% by mass, and Zn: 0.4% by mass with the balance being copper and inevitable impurities is used as an experimental material. The relationship between pre-annealing conditions, light rolling conditions, rolling conditions before pre-annealing and crystal orientation, and the effect of crystal orientation on the bendability and mechanical properties of the products were investigated.
In a high frequency melting furnace, 2.5 kg of electrolytic copper was melted using a graphite crucible having an inner diameter of 60 mm and a depth of 200 mm in an argon atmosphere. Alloy elements were added to obtain the above alloy composition, the melt temperature was adjusted to 1300 ° C., and then cast into a cast iron mold to produce an ingot having a thickness of 30 mm, a width of 60 mm, and a length of 120 mm. The ingot was processed in the following process order to produce a product sample with a plate thickness of 0.15 mm.
(1) Hot rolling: An ingot heated at 950 ° C. for 3 hours was rolled to a predetermined thickness. The material after rolling was immediately cooled with water.
(2) Grinding: The oxide scale generated by hot rolling was removed with a grinder. The grinding amount was 0.5 mm per side.
(3) Cold rolling: Cold rolling was performed to a predetermined thickness at various total processing degrees (R) and processing degrees per pass (r).
(4) Pre-annealing: The sample was inserted into an electric furnace adjusted to a predetermined temperature and held for a predetermined time, and then the sample was placed in a water bath and cooled.
(5) Light rolling: Cold rolling was performed at various rolling degrees to a thickness of 0.25 mm.
(6) Solution treatment: The sample was inserted into an electric furnace adjusted to 800 ° C. and held for 10 seconds, and then the sample was placed in a water bath and cooled. The crystal grain size after the solution treatment was about 10 μm.
(7) Aging treatment: Heated in an Ar atmosphere at 450 ° C. for 5 hours using an electric furnace.
(8) Cold rolling: Cold rolling was performed at a workability of 20% from 0.25 mm to 0.20 mm.
(9) Strain relief annealing: The sample was inserted into an electric furnace adjusted to 400 ° C. and held for 10 seconds, and then the sample was left in the air and cooled.

The following evaluation was performed on the sample after the pre-annealing and the product sample (in this case, the strain relief annealing was completed).
(Evaluation of softening degree in preliminary annealing)
About the sample before pre-annealing and after pre-annealing, the tensile strength was measured in parallel with the rolling direction according to JIS Z 2241 using a tensile tester, and the respective values were set to σ ₀ and σ. Further, a 950 ° C. annealed sample was prepared by the above procedure (water cooling when the sample reached 950 ° C. when inserted into a 1000 ° C. furnace), and the tensile strength was measured in parallel with the rolling direction to obtain σ ₉₅₀ . . The softening degree S was determined from σ ₀ , σ, and σ ₉₅₀ .
S = (σ ₀ −σ) / (σ ₀ −σ ₉₅₀ )
The tensile test piece was a No. 13B test piece specified in JIS Z 2201.

(EBSD)
A sample area of 500 μm square containing 200 or more crystal grains was scanned in steps of 0.5 μm, crystal orientation distribution was measured, and crystal orientation density function analysis was performed.
As a sample for analyzing the crystal orientation of the surface layer, the sample surface was mechanically polished to remove minute irregularities due to a rolling pattern or the like, and then finished to a mirror surface using colloidal silica abrasive grains. The surface polishing depth was in the range of 2 to 3 μm. Thereafter, the area of a region having an azimuth within 10 ° from the Cube azimuth was determined, and this area was divided by the total measurement area to obtain an area ratio.
As a sample for analyzing the crystal orientation at the center of the plate thickness, the part from one surface to the center of the plate thickness is removed by etching using a ferric chloride solution, and then mirror polished by mechanical polishing and electrolytic polishing. It was. The thickness of the sample after finishing was in the range of 45 to 55% with respect to the original plate thickness. Then, the area of the region where the angle formed by the <100> direction of the crystal and the TD is within 10 ° is obtained, and this area is divided by the total measurement area to obtain the area ratio of the crystal in which the <100> direction is oriented to TD. .
Note that the information obtained in the azimuth analysis by EBSD includes azimuth information up to a depth of several tens of nanometers at which the electron beam penetrates into the sample, but is sufficiently small with respect to the area being measured. Described.

(Product tensile test)
A specimen No. 13B specified in JIS Z 2201 was taken so that the tensile direction was parallel to the rolling direction, and a tensile test was performed in parallel with the rolling direction in accordance with JIS Z 2241 to determine the tensile strength.

(Product bending test)
A 180 degree bending test was performed instead of a 90 degree bending test such as a W bending, assuming a more severe bending process.
A strip-shaped sample having a width of 10 mm and a length of 30 mm or more was collected so that the longitudinal direction thereof was parallel to the rolling direction. A 180 ° bending test was performed in the Good Way direction (the bending axis was perpendicular to the rolling direction) with the inner radius set to S in accordance with the JIS Z 2248 push bending method. The bent section was mirror-finished by mechanical polishing and buffing, and the presence or absence of cracks was observed with an optical microscope. For bending with S of 0.05, 0.10, 0.15, 0.20, 0.25, 0.30, 0.40, 0.50, 0.60, 0.80, 1.0 mm The minimum S (S _min ) at which cracks do not occur was prepared. A value (S _min / d) obtained by dividing S _min by the plate thickness (d) was used as an index of bending workability. If S _min / d was 1.0 or less, it was judged that good Good Way bending workability was obtained.

(Young's modulus of the product)
A No. 13B specimen specified in JIS Z 2201 was sampled so that the tensile direction was perpendicular to the rolling direction, and a tensile test was performed. From the obtained stress-strain curve, the slope of the straight line portion in the elastic range was obtained, and this value was taken as the Young's modulus.
The evaluation results are shown in Tables 1 and 2.

Inventive examples are all subjected to cold rolling, pre-annealing and light rolling before pre-annealing under the conditions defined by the present invention, and the crystallographic orientation of the plate thickness surface and the central portion satisfies the provisions of the present invention, Good Way's 180 degree bend S _min / d was 1.0 or less, and at the same time, Young's modulus in the orthogonal direction of rolling of 106 MPa or more was obtained.
In Comparative Examples 1 to 3, the condition of the degree of processing (r) per pass in cold rolling before pre-annealing deviates from the definition of the present invention. In comparative example 1, r _ave is excessive, in comparative example 2, r _max is excessive, and in comparative example 3, both r _ave and r _max are excessive. In these, the area ratio of the crystals in which the <100> direction is aligned with the TD of the rolled material at the center of the plate thickness exceeded 50%, and the Young's modulus in the rolling orthogonal direction was less than 106 GPa.

  Table 3 shows the increase in each pass for Invention Example 3 and Comparative Examples 1 to 3 in which rolling was performed at a total workability (R) of 96.0% from 9.0 mm to 0.357 mm immediately before the preliminary annealing. The plate thickness and the degree of processing (r) of each pass are compared.

In conventional cold rolling of Corson alloy (especially rough rolling performed in the first half of the process), emphasis is placed on productivity, the degree of processing of each pass is set high as in Comparative Example 3, and rolling is performed with a small number of passes. Was normal.
In Comparative Example 4, the total degree of work (R) in cold rolling before pre-annealing is less than 90.0%. Since the area ratio of the Cube orientation on the surface was less than 5%, the bending workability deteriorated, and the _Smin / d of 180 degrees bending of Good Way exceeded 1.0.
In Comparative Example 5, the pre-annealing softening degree was less than 0.20, and in Comparative Example 6, the pre-annealing softening degree exceeded 0.80. In Comparative Example 7, the light rolling workability was less than 3%, and in Comparative Example 8, the light rolling workability exceeded 50%. In Comparative Examples 5 to 8, since the Cube orientation area ratio on the surface was less than 5%, the bending workability was deteriorated, and the S _min / d of 180 degrees bending of Good Way exceeded 1.0.
The comparative example 9 is manufactured according to the manufacturing method of the conventional general Corson alloy. Pre-annealing and light rolling are not performed, and in cold rolling between hot rolling and solution treatment, productivity is emphasized and r _ave is set to more than 15% and r _max is set to more than 20%. The area ratio of the Cube orientation was less than 5% on the surface, and the area ratio of crystals with the <100> direction oriented to the TD of the rolled material was 50% or less at the center of the plate thickness. Good Way 180 degree bending _Smin / d is 2.5, and bending workability is bad, On the other hand, the Young's modulus of a rolling orthogonal direction was a high value exceeding 140 GPa.
In Comparative Examples 10 to 14, Corson alloys having the alloy compositions are manufactured according to the manufacturing methods described in Patent Documents 2 to 5. Here, in cold rolling between hot rolling and pre-annealing (intermediate annealing), productivity is emphasized and r _ave is set to more than 15% and r _max is set to more than 20%.
Comparative Example 10 was manufactured according to Patent Document 2, and as conditions other than those described in Table 2, hot rolling was performed while lowering the temperature from 950 ° C. to 400 ° C., and conductive in the preliminary (intermediate) annealing. The rate is adjusted to 1.5 times or more and the hardness is adjusted to 0.8 times or less. By manufacturing under this condition, the area ratio of the Cube orientation on the surface became 5% or more, but the area ratio of the crystals in which the <100> direction was aligned with the TD of the rolled material exceeded 50% at the center of the plate thickness. . As a result, the bending workability was good, but the Young's modulus in the direction perpendicular to the rolling was less than 106 GPa.
Comparative Example 11 was manufactured according to Patent Document 3, and as a condition other than those described in Table 2, the temperature increase rate in the range of 400 to 750 ° C. was 2 to 50 ° C./second in the solution treatment. . By manufacturing under these conditions, the area ratio of Cube orientation was 5 to 60%, and the area ratio of Brass orientation and Copper orientation was 20% or less. On the other hand, the area ratio of crystals in which the <100> direction is aligned with the TD of the rolled material at the center of the plate thickness exceeded 50%. As a result, the bending workability was good, but the Young's modulus in the direction perpendicular to the rolling was less than 106 GPa.
The comparative example 12 was manufactured according to patent document 4, and the electrical conductivity was adjusted to the range of 20 to 45% IACS in pre-annealing as conditions other than those described in Table 2. By manufacturing under these conditions, the area ratio of the Cube orientation is 10 to 80%, the area ratios of the Brass orientation and the Copper orientation are both 20% or less, and notch bending is possible at the center in the thickness direction. . On the other hand, the area ratio of crystals in which the <100> direction is aligned with the TD of the rolled material at the center of the plate thickness exceeded 50%. As a result, the bending workability was good, but the Young's modulus in the direction perpendicular to the rolling was less than 106 GPa.
Comparative Example 13 was manufactured according to Patent Document 5, and as a condition other than those described in Table 2, in hot rolling, the processing rate of one pass was 30% or less, and the holding time between each pass was 20 to 20%. 100 seconds. Further, the solution treatment was performed at 900 ° C., and the average crystal grain size was adjusted to a range of 12 to 100 μm. By manufacturing under these conditions, W0 / W4 is 0.8 to 1.5, W0 is 5 to 48% (W0 and W4 are the surface layer and depth position of the material, respectively, at the 1/4 position of the whole. Cube orientation area ratio), and 180-degree contact bending with a 1.0 mm wide test piece is possible (the narrower the test piece width, the easier the bending process is), and the stress relaxation value when heated at 150 ° C. for 1000 hours is 30%. It became the following. On the other hand, the area ratio of crystals in which the <100> direction is aligned with the TD of the rolled material at the center of the plate thickness exceeded 50%. As a result, the bending workability (test specimen width 10 mm) was good, but the Young's modulus in the direction perpendicular to the rolling was less than 106 GPa.
The comparative example 14 was manufactured according to patent document 6, and it annealed to 350 degreeC after hot rolling as conditions other than having described in Table 2. FIG. By manufacturing under these conditions, the area ratio of the (100) plane facing the rolling direction was 30% or more, and the Young's modulus in the rolling parallel direction was 110 GPa or less. On the other hand, the area ratio of the Cube orientation on the surface was slightly less than 5%, and the area ratio of the crystals in which the <100> direction was aligned with the TD of the rolled material exceeded 50% at the center of the plate thickness. As a result, the bending workability was slightly poor and the Young's modulus in the direction perpendicular to the rolling was less than 106 GPa.

(Example 2)
It was examined whether the bending workability improving effect shown in Example 1 could be obtained even with a Corson alloy having different components and manufacturing conditions.
First, casting was performed in the same manner as in Example 1 to obtain ingots having the components shown in Tables 4 and 5.
(1) Hot rolling: An ingot heated at 950 ° C. for 3 hours was rolled to a predetermined thickness. The material after rolling was immediately cooled with water.
(2) Grinding: The oxide scale generated by hot rolling was removed with a grinder. The grinding amount was 0.5 mm per side.
(3) Cold rolling: Cold rolling was performed to a predetermined thickness at various total processing degrees (R) and processing degrees per pass (r).
(4) Pre-annealing: The sample was inserted into an electric furnace adjusted to a predetermined temperature and held for a predetermined time, and then the sample was placed in a water bath and cooled.
(5) Light rolling (6) Solution treatment: The sample was inserted into an electric furnace adjusted to a predetermined temperature and held for 10 seconds, and then the sample was placed in a water bath and cooled. The temperature was selected so that the average diameter of the recrystallized grains was in the range of 5 to 25 μm.
(7) Cold rolling (Rolling 1)
(8) Aging treatment: Heating was performed in an Ar atmosphere using an electric furnace at a predetermined temperature for 5 hours. The temperature was selected to maximize the tensile strength after aging.
(9) Cold rolling (Rolling 2)
(10) Strain relief annealing: The sample was inserted into an electric furnace adjusted to a predetermined temperature and held for 10 seconds, and then the sample was left in the air and cooled.

  Evaluation similar to Example 1 was performed about the sample after preliminary annealing, and a product sample. Table 6 shows the evaluation results. When rolling 1 or rolling 2 is not performed, “0” is written in the column of each degree of processing. In the case where the strain relief annealing is not performed, “none” is written in the temperature column.

Inventive examples are all subjected to cold rolling, pre-annealing and light rolling before pre-annealing under the conditions defined by the present invention, and the crystallographic orientation of the plate thickness surface and the central portion satisfies the provisions of the present invention, Good Way's 180 degree bend S _min / d was 1.0 or less, and at the same time, Young's modulus in the orthogonal direction of rolling exceeding 106 MPa was obtained. A high tensile strength exceeding 650 MPa was also obtained.
In Comparative Examples 15, 21, 22, 23, 25, and 27, the condition of the degree of work (r) per pass in cold rolling before pre-annealing deviates from the definition of the present invention. For this reason, the area ratio of the crystals in which the <100> direction is aligned with the TD of the rolled material at the center of the plate thickness exceeded 50%, and the Young's modulus in the direction perpendicular to the rolling was less than 106 GPa.
In Comparative Example 17, the total degree of work (R) in cold rolling before pre-annealing is less than 90.0%. In Comparative Examples 18 and 26, the light rolling workability did not satisfy the provisions of the present invention. In Comparative Examples 16 and 24, the degree of softening of the pre-annealing did not satisfy the definition of the present invention. In these, the area ratio of the Cube orientation on the surface was less than 5%, and S _min / d exceeded 1.0.
Comparative Examples 19, 20, and 28 were obtained by performing cold rolling, pre-annealing, and light rolling before pre-annealing under the conditions specified by the present invention. In Comparative Example 20, the workability of rolling 1 was 60%. In Comparative Examples 19 and 28, the workability of rolling 2 exceeded 50%. For this reason, the area ratio of the Cube orientation on the surface was less than 5%, and S _min / d exceeded 1.0.
In Comparative Example 29, the total concentration of Ni and Co and the Si concentration were lower than those specified in the present invention. Crystal orientation satisfies the requirements of the present invention, although less than 1.0 S _min / d and rolling orthogonal direction Young's modulus greater than 106GPa were obtained, the tensile strength did not reach even 500 MPa.
In Comparative Example 30, the total concentration of Ni and Co exceeds the definition of the present invention. The area ratio of the Cube orientation on the surface was 5% or more, but S _min / d exceeded 1.0.
Comparative Example 31 was produced according to the method proposed by Patent Document 1, and pre-annealing and light rolling were not performed. Conditions other than those described in Table 5 were solution treatment, aging treatment, and strain relief annealing (short). The cooling rate of time annealing is set to 10 ° C./second or more and less than 10 ° C./second and 10 ° C./second or more, the decrease in conductivity in short-time annealing is 0.5 to 3% IACS, and the average crystal grain size is 10 μm. It was as follows. Further, in the cold rolling between the hot rolling and solution treatment, more than 15% of the r _ave emphasizes productivity, was set r _max 20 percent. As a result, the electrical conductivity was 35% IACS, the proof stress was 700 MPa or more, and Bad Way 90 degree W bending workability was good, but Good Way 180 degree bending workability was inferior to that of the present invention example. . According to Patent Document 1, the Cube orientation area ratio of the surface becomes 50% or more by manufacturing by the above method, but the Cube orientation area ratio obtained in this experiment was less than 5%. The cause of this wrinkle could not be clarified.

Claims (8)

One or more of Ni and Co is 0.8 to 5.0 mass%, Si is 0.2 to 1.5 mass%, and the balance is a rolled material made of copper and inevitable impurities,
The area ratio of the Cube orientation {001} <100>, which is the area ratio of the region having an orientation within 10 ° from the Cube orientation on the surface of the rolled material, is 5 to 80%.
In a cross section having a depth of 45 to 55% with respect to the plate thickness, the <100> direction, which is the area ratio of the region where the angle formed by the <100> direction and TD is within 10 °, is the width direction (TD) of the rolled material. A Corson alloy having an area ratio of oriented crystals of 50% or less.   The Corson alloy of Claim 1 which contains 0.005-3.0 mass% of 1 or more types in total in Sn, Zn, Mg, Fe, Ti, Zr, Cr, Al, P, Mn, and Ag.   The Corson alloy according to claim 1 or 2, wherein the Young's modulus obtained from a tensile test in a direction orthogonal to the rolling direction is 106 GPa or more.   The Corson alloy in any one of Claims 1-3 used as a raw material of the end surface contact type terminal extract | collected in the direction orthogonal to a rolling direction. One or more of Ni and Co is contained in an amount of 0.8 to 5.0 mass%, Si is contained in an amount of 0.2 to 1.5 mass%, and the balance is made of copper and inevitable impurities. Hot rolling from a temperature of ˜1000 ° C. to a thickness of 3-20 mm, cold rolling with a workability of 90-99.8%, maximum value and average value of workability per pass of 20% or less and 15%, respectively After the following, pre-annealing with a softening degree of 0.20 to 0.80, cold rolling with a working degree of 3 to 50%, solution treatment at 700 to 950 ° C. for 5 to 300 seconds, working degree of 0 to 60% Cold rolling, aging treatment at 350 to 600 ° C. for 2 to 20 hours, cold rolling at a working degree of 0 to 50% is sequentially performed,
The softening degree is defined as S,
S = (σ ₀ −σ) / (σ ₀ −σ ₉₅₀ )
[Where σ ₀ is the tensile strength before pre-annealing, and σ and σ ₉₅₀ are the tensile strength after pre-annealing and after annealing at 950 ° C., respectively. ]
The manufacturing method of the Corson alloy in any one of Claims 1-4 shown by these.   The said ingot contains 0.005-3.0 mass% of 1 or more types in total in Sn, Zn, Mg, Fe, Ti, Zr, Cr, Al, P, Mn, and Ag in total amount. Corson alloy manufacturing method.   The copper-stretched article provided with the Corson alloy in any one of Claims 1-4.   The electronic device component provided with the Corson alloy in any one of Claims 1-4.

Images