JP5607459B2 - Copper alloy ingot, method for producing the same, and copper alloy sheet obtained therefrom - Google Patents

Description

  The present invention relates to a copper alloy ingot applied as an electrical / electronic device material such as a lead frame, a terminal, a connector, a wire harness, a terminal, a relay, a switch, a spring material, a target material, and further as a nuclear reactor structural material, and The production method and a copper alloy sheet obtained therefrom.

  The following points may be observed in the cross section of a normal continuous casting ingot of copper and copper alloy. A state having a coarse granular crystal part in the vicinity of the center and a coarse columnar crystal part surrounding the coarse granular crystal part arranged so as to surround the final solidified part with porosity at the center, or a final solidified part with porosity at the center. Only the rough columnar crystals surround almost the entire surface. Thin plates obtained from ingots having such coarse granular crystals and columnar crystals, or only columnar crystals, may be inferior in moldability, and in order to use them for electrical and electronic equipment applications, Improvements were sought. Further, in the thick plate obtained from the ingot having the granular crystal and the columnar crystal, or only the columnar crystal, a defect such as porosity remains in the center, so that a healthy copper plate may not be provided, and further improvement is demanded. It was.

  By the way, in the field of steel, equiaxed crystals increase when the degree of superheated molten steel is low, and it has been shown that low temperature casting is effective for equiaxed crystallization (see Non-Patent Document 1). Patent Document 1 describes a technique for making columnar crystals equiaxed by applying a unidirectional swirling flow to molten steel near the solidification interface using an induction electromagnetic stirrer and dividing columnar dendrites. Has been. In continuous casting of molten steel, these techniques are effective alone or in combination.

Japanese Patent Laid-Open No. 50-23338

"Handbook of Iron and Steel" 3rd edition, II Steelmaking and Steelmaking, p. 653

Unlike the case of the steel, in the continuous casting of a copper alloy, the low temperature casting technique alone does not provide a sufficient effect. In other words, in the induction electromagnetic stirring technique, the penetration depth of the magnetic field is small with copper having high electrical conductivity, and sufficient stirring cannot be performed. Furthermore, in low-temperature casting, the effect increases as the degree of superheat of the molten metal approaches the liquidus temperature, but casting abnormalities such as clogging of the immersion nozzle and entrapment of oxide occur. For this reason, in the continuous casting of copper and copper alloys, a temperature that is 50 to 100 ° C. higher than the liquidus temperature (hereinafter referred to as +50 to 100 ° C.) is practically used. However, under such temperature conditions, the effect of miniaturization, that is, the effect of equiaxed crystal is hardly obtained.
In the present invention, in view of such a current situation, a copper alloy ingot that is less likely to crack even in severe bending, can achieve high strength, and suppresses the occurrence of blowholes in the ingot. And a method for producing the same, and a copper alloy sheet obtained therefrom.

The above problem has been solved by the following means.
(1) A copper alloy ingot in which the equiaxed crystal area ratio represented by the following formula in the metal structure of the ingot cross section is 70% or more, and the crystal grain size of the equiaxed crystal is 5 mm or less , and The copper alloy board | plate material manufactured from the ingot of the copper alloy which has a component composition in any one of following A-E .
Equiaxial crystal area ratio = equiaxed crystal area in the ingot cross section / ingot cross section area x 100 (%)
<A> Ni: 2.0 to 6.0% by mass
Si: 0.3-2.0 mass%
The balance is Cu and inevitable impurities
<B> Sn: 3.0 to 11.0% by mass
P: 0.03-0.30 mass%
The balance is Cu and inevitable impurities
<C> Fe: 0.1 to 2.5% by mass
P: 0.01-0.10 mass%
The balance is Cu and inevitable impurities
<D> Co: 0.5 to 2.0% by mass
Si: 0.10 to 0.55 mass%
The balance is Cu and inevitable impurities
<E> Ti: 0.1 to 3.5% by mass
The balance is Cu and inevitable impurities ( 2 ), which is a copper alloy material composed of the component composition A, and the size of a crystallized substance mainly composed of Ni and Si present in the structure is 5 μm or less. The copper alloy sheet material according to ( 1 ).
(3) the A copper alloy material consisting of chemical composition C, copper according to (1) the size of the crystallized substances composed mainly of Fe present in the tissue is 10μm or less Alloy plate material.
( 4 ) A copper alloy material composed of the component composition D, characterized in that the size of a crystallized substance mainly composed of Co and Si present in the structure is 1.2 μm or less ( 1 ) The copper alloy sheet material described in 1.
( 5 ) A copper alloy material composed of the component composition E, wherein the size of a crystallized product mainly composed of Ti present in the structure is 3.0 μm or less. ( 1 ) Copper alloy sheet material.
( 6 ) A method for producing a copper ingot having a composition of any of the following A to E, wherein when the copper alloy is continuously cast, the temperature of the molten copper alloy is set to 150 ° C. as its liquidus temperature. The equiaxed crystal area ratio represented by the following formula in the metal structure of the cross-section of the cast ingot is 70% or more, and the equiaxed crystal. The manufacturing method of the copper alloy ingot characterized by making the crystal grain size of 5 mm or less.
Equiaxial crystal area ratio = equiaxed crystal area in the ingot cross section / ingot cross section area x 100 (%)
<A> Ni: 2.0 to 6.0% by mass
Si: 0.3-2.0 mass%
The balance is Cu and inevitable impurities
<B> Sn: 3.0 to 11.0% by mass
P: 0.03-0.30 mass%
The balance is Cu and inevitable impurities
<C> Fe: 0.1 to 2.5% by mass
P: 0.01-0.10 mass%
The balance is Cu and inevitable impurities
<D> Co: 0.5 to 2.0% by mass
Si: 0.10 to 0.55 mass%
The balance is Cu and inevitable impurities
<E> Ti: 0.1 to 3.5% by mass
The method for producing an ingot according to ( 6 ), characterized in that a hot top portion made of a refractory material or a heat insulating material is provided on the upper part of the continuous casting mold with Cu and inevitable impurities ( 7 ) remaining .

  According to the ingot of the copper alloy of the present invention, the manufacturing method thereof, and the copper alloy plate material obtained from the ingot, it is difficult to cause cracking even in severe bending, and high strength can be realized. There is an excellent effect that the occurrence of blowholes in can be suppressed.

  According to a preferred embodiment of the present invention, a continuous cast ingot having a fine equiaxed crystal structure in the ingot surface layer and the inside of the ingot can be produced. Specifically, the equiaxed crystal area ratio of the copper alloy ingot can be set to 70% or more, and the crystal grain size of the equiaxed crystal can be set to 5 mm or less. Therefore, it is possible to provide a material with excellent molding processability for thin plates, suppressing the occurrence of coarse crystallized materials in alloy materials, and providing a healthy copper plate with no defects such as porosity remaining in the center of thick plates Is possible. Utilizing these characteristics, it is possible to provide copper alloy materials suitable for electrical and electronic equipment such as lead frames, terminals, connectors, wire harnesses, terminals, relays, switches, spring materials, target materials, and nuclear reactor structural materials. it can. Hereinafter, preferred embodiments of the present invention will be described in detail.

[Casting method]
In the present embodiment, the generation and retention of equiaxed crystal nuclei is efficiently performed in continuous casting. Specifically, fine nuclei are dispersed in molten copper by stirring, and remelting of nuclei is prevented by reducing the degree of superheat.

(Stirring)
First, the form of stirring will be described. For stirring, electromagnetic stirring such as that performed by continuous casting of molten steel can be performed. However, the penetration depth of the magnetic field is small with copper having high electrical conductivity, and sufficient stirring cannot be performed. On the other hand, in this embodiment, so-called mechanical stirring is used in which a stirring bar provided with a stirrer is immersed in the molten copper surface above the continuous casting mold and the stirrer is rotated. Nucleation can be promoted by fusing the dendrite of the solidified shell by stirring. The rotating body itself can also be used as a nucleation site. However, in order to increase the number of equiaxed nuclei by stirring, it is necessary to increase the swirl speed of the stirring bar. In the present invention, the peripheral speed at the time of rotation of the stirrer for stirring the molten copper is defined as the swirling flow velocity, and the swirling flow velocity is 60 to 3000 mm / sec. It was. In this range, the dendrite is melted by stirring, and the effect of equiaxed crystallization and refinement can be sufficiently obtained. The swirl flow rate is 60 mm / sec. If it is less than 1, the flow rate sufficient to melt the dendrite cannot be obtained, and the effect of miniaturization is insufficient. The swirl flow rate is 3000 mm / min. If it is larger, the effect of equiaxed crystallization and refinement can be obtained, but there is a problem that entrainment of blowholes, bubbles and oxides increases. Although it is not unambiguous, the higher the swirl flow rate, the lower the equiaxed crystal area ratio in the copper alloy ingot and the smaller the equiaxed crystal grain size.

(Molten copper temperature)
Next, an appropriate condition of the molten copper temperature will be described. As described above, even if low temperature casting is aimed at in continuous casting of copper alloy (continuous casting of copper and / or copper alloy), the liquidus temperature is about +50 to 100 ° C. in practical use. Even if the low-temperature casting is directed without adding, there are few equiaxed nuclei in the molten copper, and a sufficient effect cannot be obtained. However, the effect of equiaxed crystallization and refinement is exhibited under conditions combined with stirring. In the present embodiment, the molten copper is in the range from the liquidus temperature + 150 ° C. or lower to the liquidus temperature or higher. In this range, since the equiaxed crystal nuclei generated by stirring are difficult to dissolve again, equiaxed crystallization and refinement proceed more than stirring alone. Desirably, the range of the liquidus temperature + 100 ° C. or lower to the liquidus temperature or higher is more effective, and more desirably the range of the liquidus temperature + 50 ° C. or lower to the liquidus temperature or higher is more effective. When the liquidus temperature is higher than + 150 ° C., the core re-dissolves even under conditions combined with stirring, and a sufficient effect cannot be obtained. Further, if the temperature is lower than the liquidus temperature, it becomes a solid-liquid coexistence region, so that there are problems such as wear of the stirring bar and defects such as blow holes. Although it is not unambiguous, as the molten copper temperature is brought closer to the liquidus temperature, the equiaxed crystal area ratio in the copper alloy ingot increases, and the grain size of the equiaxed crystal tends to decrease.

(Bath pool)
Furthermore, as a desirable mode for carrying out the invention, it is desirable to dispose a hot water reservoir portion (hereinafter referred to as a hot top portion) surrounded by a refractory or a heat insulating material on the upper part of the copper mold of the mold. By setting the level of the molten metal surface in the mold to the hot top portion above the upper end of the copper mold, it is possible to prevent bubbles and oxides caught by stirring from being trapped in the solidified shell. . In addition, by connecting the hot top part and TND with scissors, there is no need to use an immersion nozzle for molten copper transfer, and the molten copper temperature is increased from a liquidus temperature of + 50 ° C. or less, which is highly equiaxed and refined. Even in the range of the phase line temperature or higher, the problem that the immersion nozzle is blocked can be avoided.
As can be seen from the above description, the present embodiment is not limited to the application to the slab shape, and even when applied to the billet shape, the effect of refining the solidified structure can be sufficiently obtained.

[Copper alloy]
A copper alloy in a preferred embodiment of the present invention will be described. The alloy described below shows an alloy having a particularly significant effect, and does not limit the type of the alloy.

(A: Cu-Ni-Si alloy)
In the embodiment to which the Cu—Ni—Si alloy is applied, Ni is 2.0 to 6.0% (mass%, the same applies hereinafter) (preferably 2.2 to 4.5%), and Si is 0.3 to 0.3%. A copper alloy material containing 2.0% (preferably 0.5 to 1.2%) and the balance of Cu and inevitable impurities can be preferably used. By using this alloy, it is possible to obtain a precipitation-strengthened alloy in which Ni and Si are added to Cu and the Ni—Si compound is finely precipitated. The following two important heat treatments are incorporated into the process for producing the precipitation strengthened alloy. First, a so-called aging precipitation treatment in which Ni and Si are dissolved in a Cu matrix at a high temperature (usually 700 ° C. or more) called a solution treatment and a heat treatment at a temperature lower than the solution treatment temperature. is there. By this aging precipitation treatment, Ni and Si dissolved at a high temperature can be precipitated. Thus, this alloy can be manufactured using the difference in the amount of atoms in which Ni and Si are dissolved in Cu at high and low temperatures.
For Ni and Si, the strength of the copper alloy material can be improved by precipitation strengthening of the Ni—Si compound by controlling the addition ratio of Ni and Si. In the present embodiment, the Ni content is 2.0 to 6.0%, preferably 2.2 to 4.5%. The Si content is 0.3 to 2.0%, preferably 0.5 to 1.2%. When Ni or Si is not less than the above lower limit, sufficient strength is obtained, and when Ni or Si is not more than the above upper limit, coarse crystallized products are not formed during casting, and the workability of the final product is not deteriorated. preferable. The size of the crystallized product is greatly affected by the casting conditions, and the effect of the heat treatment in the subsequent process is minor.
When casting is carried out with this composition, coarse crystallized products may remain up to the final product, causing cracks in the processing process and defective plating in the plating process. If the casting method mentioned above is implemented, the coarse crystallization thing can be made smaller by stirring and the crystallization thing of a final product can also be made small. Thereby, workability and plating property can be improved.
In the present alloy system, the size of a crystallized substance mainly composed of Ni and Si present in the structure is preferably 5 μm or less, and more preferably 0.1 to 2.0 μm. By setting the size of the crystallized material within this range, it is preferable because the influence on cracking and plating defects in the processing step can be further reduced.

(B: Cu-Sn-P alloy)
In the case of an embodiment to which a Cu-Sn-P alloy is applied, Sn is contained in an amount of 3.0 to 11.0% (mass%, the same applies hereinafter), P is contained in an amount of 0.03 to 0.30%, and the remainder is inevitable with Cu. A copper alloy material made of impurities can be preferably used. By using this alloy, Sn can be dissolved in Cu to form a solid solution strengthened alloy. In the process of manufacturing this solid solution strengthened alloy, the Sn compound phase (mainly hard and brittle δ phase and γ phase) is solidified in the Cu matrix at a high temperature (normally 500 ° C. or more) called homogenization heat treatment. There is a heat treatment for melting. Also, when the base material is hardened by work hardening, there is a heat treatment for the purpose of recrystallization and recovery.
About Sn, intensity | strength can be improved, so that there is much solid solution amount. The Sn content is 3.0 to 11.0%. When the amount is not less than this lower limit value, the strength is sufficient, and when it is not more than the above upper limit value, the Sn compound phase does not become too large, and it is preferable that much time is not required for the homogenization heat treatment. P affects the castability and corrosion resistance. The P content is 0.03 to 0.30%, preferably 0.08 to 0.20%. If it is above this lower limit value, the castability and the like do not deteriorate too much, and if it is not more than the above upper limit value, a compound having low workability such as Cu ₂ P is not formed too much.
In the process after casting with this composition and homogenization heat treatment, the finer the crystal grain size, the better the workability. Conversely, an ingot having a coarse crystal grain size may be cracked by processing in an intermediate process. Therefore, if the above casting method is carried out, the crystal grain size can be refined by stirring, so that the workability is improved and the possibility of occurrence of cracks in the intermediate process can be reduced.

(C: Cu-Fe-P alloy)
In the embodiment to which the Cu—Fe—P alloy is applied, Fe is 0.1 to 2.5% (mass%, the same applies hereinafter) (preferably 1.0 to 2.3%), and P is 0.01 to A copper alloy material containing 0.10% (preferably 0.02 to 0.04%) and the balance of Cu and inevitable impurities can be preferably used. By using this alloy, it is possible to obtain a precipitation-strengthened alloy in which Fe and P are added to Cu and a compound containing Fe is finely precipitated. In order to finely precipitate a compound containing Fe, it is necessary to dissolve a large amount of Fe, and when a coarse Fe compound is formed during melt casting, the amount of finely precipitated Fe compound is added to the addition amount. On the other hand, it decreases relatively.
Fe is an element that basically increases the strength, but if the amount is not less than the above lower limit value, the precipitation of fine Fe compounds is not a little, and the strength is sufficient. In addition, when the amount is not more than the above upper limit value, a coarse Fe compound is preferable because it does not easily crystallize and precipitate during casting, and does not deteriorate the workability of the final product. P has a deoxidizing action and improves castability, and also forms a fine compound with Fe and contributes to an improvement in strength. When P is above the lower limit, the presence of Fe contributes to precipitation strengthening. On the other hand, when the amount is not more than the above upper limit, the solid solubility limit of Fe does not decrease, and a coarse crystallized product is not formed during casting. The size of the crystallized product is greatly affected by the casting conditions, and the effect of the heat treatment in the subsequent process is minor.
When casting is carried out with this composition, coarse crystallized products may remain up to the final product, causing cracks in the processing process and defective plating in the plating process. If the casting method mentioned above is implemented, a coarse crystallization thing can be made smaller by stirring and the crystallization thing of a final product can be made small. Thereby, workability and plating property can be improved.
From the above viewpoint, the size of the crystallized product mainly composed of Fe present in the structure is preferably 10 μm or less, and more preferably 0.1 to 5.0 μm. By setting the size of the crystallized material within this range, it is preferable because the influence on cracking and plating defects in the processing step can be further reduced.

(D: Cu-Co-Si alloy)
In the case of an embodiment to which a Cu—Co—Si alloy is applied, Co is contained in an amount of 0.5 to 2.0% (mass%, the same applies hereinafter), Si is contained in an amount of 0.10 to 0.55%, and the balance is Cu. A copper alloy material made of impurities can be preferably used. By using this alloy, it is possible to obtain a precipitation-strengthened alloy in which Co and Si are added to Cu and the Co—Si compound is finely precipitated. The following two important heat treatments are incorporated into the process for producing the precipitation strengthened alloy. First, a so-called aging precipitation treatment in which Co and Si are dissolved in a Cu matrix at a high temperature (usually 700 ° C. or more) called a solution treatment and a heat treatment at a temperature lower than the solution treatment temperature. is there. By this aging precipitation treatment, Co and Si dissolved at a high temperature can be precipitated. Thus, this alloy can be manufactured using the difference in the amount of atoms in which Co and Si are dissolved in Cu at high and low temperatures.
As for Co and Si, the strength of the copper alloy material can be improved by precipitation strengthening of the Co—Si compound by controlling the addition ratio of Co and Si. The Co content is 0.5 to 2.0%, preferably 0.7 to 1.5%. The Si content is 0.1 to 0.55%, preferably 0.2 to 0.45%. When Co is not less than the above lower limit value or Si is not less than the above lower limit value, sufficient strength can be obtained, and when Co is not more than the above upper limit value or when Si is greater than 0.55%, a coarse crystallized product is formed during casting. And reduce the workability of the final product. The size of the crystallized product is greatly affected by the casting conditions, and the effect of the heat treatment in the subsequent process is minor.
When casting is performed with this composition, coarse crystals remain up to the final product, causing cracks in the processing process and plating defects in the plating process. By carrying out the casting method of the present invention, the coarse crystallized product can be made smaller by stirring, and the crystallized product of the final product can also be made smaller. Thereby, workability and plating property can be improved.
From the above viewpoint, the size of a crystallized substance mainly composed of Co and Si present in the structure is preferably 1.2 μm or less, and more preferably 0.1 to 0.8 μm. . By setting the size of the crystallized material within this range, it is preferable because the influence on cracking and plating defects in the processing step can be further reduced.

(E: Cu-Ti alloy)
In the case of an embodiment to which a Cu-Ti alloy is applied, Ti is contained in an amount of 0.1 to 3.5% (mass%, the same applies hereinafter) (preferably 1.5 to 3.2%), and the balance is Cu and inevitable impurities. The copper alloy material which consists of can be used preferably. By using this alloy, it is possible to obtain a precipitation-strengthened alloy in which Ti is added to Cu and a Cu-Ti compound is finely precipitated. The following two important heat treatments are incorporated into the process for producing the precipitation strengthened alloy. First, there are a so-called aging precipitation treatment in which Ti is solid-dissolved in a Cu matrix at a high temperature (usually 700 ° C. or more) called a solution treatment and a heat treatment at a temperature lower than the solution treatment temperature. By this aging precipitation treatment, Ti dissolved at a high temperature can be precipitated. Thus, this alloy can be manufactured using the difference in the amount of atoms in which Ti is dissolved in Cu at high and low temperatures.
Ti is that the Cu 4 _Ti is finely precipitated during aging heat treatment, it is possible to increase the strength of the material. When the Ti content is not less than the above lower limit, sufficient strength can be obtained. When the Ti content is less than or equal to the above upper limit value, it is preferable in that a coarse Ti crystallized product (including intermetallic compounds and oxides) is not formed, and the workability of the final product is not lowered. The size of the crystallized product is greatly affected by the casting conditions, and the effect of the heat treatment in the subsequent process is minor.
When casting is carried out with this composition, coarse crystallized products may remain up to the final product, causing cracks in the processing process and defective plating in the plating process. If the casting method mentioned above is implemented, the coarse crystallization thing can be made smaller by stirring and the crystallization thing of a final product can also be made small. Thereby, workability and plating property can be improved.
From the above viewpoint, the size of the crystallized product mainly composed of Ti present in the structure is preferably 3.0 μm or less, more preferably 0.1 to 2.0 μm. By setting the size of the crystallized material within this range, it is preferable because the influence on cracking and plating defects in the processing step can be further reduced.

  The copper alloy plate material of the present invention is a copper alloy material having a specific shape, for example, a plate material, a strip material, a wire material, a rod material, a foil, etc., and can be used for any electric / electronic component, Although not limited, for example, it is suitably used for parts such as lead frames, terminals, connectors, wire harnesses, terminals, relays, switches, spring materials, target materials, and other electrical / electronic devices, and nuclear reactor structural materials. It is done.

  Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited thereto.

  The copper alloy used for the Example and comparative example of this invention is an alloy which contains the component shown in Tables 1-5, and a remainder consists of Cu and an inevitable impurity. Each of these alloys was melted in the atmosphere under a charcoal coating in a coreless furnace (high frequency induction melting furnace), and when the molten copper reached a predetermined temperature, it was cast into a mold surrounded by a copper mold on four sides. At the time of casting, a graphite stirrer was immersed from the top surface of the molten metal, and the molten copper was solidified while stirring to produce an ingot having a thickness of 120 mm, a width of 350 mm, and a length of 1200 mm. Note that only the Ti—Cu alloy was melt-cast in a coreless furnace in a seal gas atmosphere (for example, Ar). In all of the examples and comparative examples, the peripheral speed during rotation of the stirrer was defined as the swirl flow velocity, and the TND temperature was defined as the molten copper temperature.

[Casting structure (Equiaxial crystal area ratio / Blowhole)]
The cast structure was evaluated by observing the macro structure by cutting the cross section of the ingot and etching. The definition of the equiaxed crystal area ratio was as follows.
Equiaxial crystal area ratio = (Equiaxial crystal area in ingot cross section / ingot cross section area) × 100.
The presence or absence of blowholes was observed on the cross-section of the ingot, by appearance observation and color check.

[0.2% yield strength]
In the tensile test, three test pieces of JIS Z2201-13B cut out in parallel with the rolling direction from the test material were measured according to JIS Z2241 under the conditions of a tensile speed of 50 mm / min and a gauge length of 50 mm. The average value of% yield strength is shown.

[W bending test]
In the W-bending test, a 10 mm width and 25 mm length were cut out perpendicular to the rolling direction, and W bending was performed so that the bending axis was perpendicular to the rolling direction. Observed and examined for cracks. The case where there was no crack in the bent part was determined as “no crack”, and the case where there was a crack was determined as “with crack”. The bending angle of each bent portion was 90 °, and the inner radius of the bent portion was 0.15 mm.

[Particle size of crystallized product]
For the evaluation of crystallized materials, after grinding the copper alloy sheet material in the rolling direction and the cross-section in parallel, photograph each crystal of 20 or more with SEM, calculate the diameter from the crystallized material area by image analysis, and calculate the average. The particle diameter was taken.

Example 1
Each alloy ingot was cast using the Cu-Ni-Si alloy shown in the table below.

As a result, the equiaxed crystal size and the equiaxed crystal ratio of the solidified structure as shown in the above table are obtained, and the fine equiaxed crystals are obviously increased by the present invention, which shows that the method of the present invention is effective.
Ingots produced by the above method are processed to a thickness of 0.15 mm by homogenization treatment under general conditions-hot rolling-face milling-cold rolling-solution heat treatment-cold rolling-aging heat treatment Then, a plate material was obtained, and a crystallized product in a cross section was observed. As a result, the crystallized product sizes shown in the above table are obtained, and it can be seen that the crystallized product is reduced by the present invention.
The plate material obtained by casting at the concentrations of Ni and Si shown in Table 1 and performing the above processing was subjected to a tensile test and W bending. As a result, as shown in the above table, except for the above concentrations, even when cast under the following condition A, a 0.2% proof stress evaluation results in insufficient strength and cracking starting from the crystallized material in the W bending process occurs. . Ni and Si are within the above composition range, and casting by the casting method of the present invention can provide a thin plate for electrical / electronic equipment with remarkably excellent molding processability.
C13 and C14 are comparative examples of the solving means (2) term, and C15 is a comparative example of the solving means (7) term.
[Condition A]
The temperature of the molten copper alloy is set to a range equal to or lower than the temperature obtained by adding 150 ° C. to the liquidus temperature, and the mixture is stirred and solidified at a swirling flow rate of 60 to 3000 mm / sec.

(Example 2)
Each alloy ingot was cast using the Cu-Sn-P alloys shown in the table below.

As a result, the equiaxed crystal size and the equiaxed crystal ratio of the solidified structure as shown in the above table are obtained, and the fine equiaxed crystals are obviously increased by the present invention, which shows that the method of the present invention is effective.
Further, the ingot produced by the above method is subjected to homogenization treatment at 500 to 700 ° C. for 1 to 10 hours and cold rolling at a processing rate of 10 to 70%. Cold rolling was repeated to obtain a plate material by processing to a thickness of 0.15 mm. At that time, the material was not able to withstand the processing by the cold rolling after the homogenization heat treatment, and cracking occurred, and the result is shown in the above table. It is clear that no processing cracks have occurred in the sample refined according to the present invention.
A tensile test was performed on the plate material obtained by casting at the concentrations of Sn and P shown in the above table and performing the above processing. As a result, as shown in the above table, even if cast under the above condition A except for the above concentration, the strength is insufficient with 0.2% proof stress, or the strength is too high in cold rolling after homogenization heat treatment. It is thought that processing cracks occur. Sn and P are in the above composition range, and casting by the casting method of the present invention can provide a thin plate for use in electrical / electronic equipment that is remarkably excellent in formability.
C25 and 26 are comparative examples of the solving means (2) term, and C27 is a comparative example of the solving means (7) term.

(Example 3)
Each alloy ingot was cast using a Cu-Fe-P alloy shown in the table below.

As a result, the equiaxed crystal size and the equiaxed crystal ratio of the solidified structure as shown in the above table are obtained, and the fine equiaxed crystals are obviously increased by the present invention, which shows that the method of the present invention is effective.
Ingots produced by the above method are processed to a thickness of 0.15 mm by homogenization treatment under general conditions-hot rolling-face milling-cold rolling-solution heat treatment-cold rolling-aging heat treatment Then, a plate material was obtained, and a crystallized product in a cross section was observed. As a result, the crystallized size as shown in the above table is obtained, and it can be clearly seen that the crystallized product is reduced by the present invention.
A tensile test and a W-bending were performed on the plate material obtained by casting at the concentrations of Fe and P shown in the above table and performing the above processing. As a result, as shown in the above table, cracks originating from the crystallized material occur due to insufficient strength in the 0.2% proof stress evaluation or W-bending, even if cast under the above condition A, except for the above concentrations. . Fe and P are within the above composition range, and casting by the casting method of the present invention can provide a thin plate for electrical / electronic equipment that is remarkably excellent in molding processability.
C35 and 36 are comparative examples of the solving means (2) term, and C31 and 32 are comparative examples of the solving means (7) term.

Example 4
Each alloy ingot was cast using a Cu—Co—Si alloy shown in the following table.

As a result, the equiaxed crystal size and the equiaxed crystal ratio of the solidified structure as shown in the above table are obtained, and the fine equiaxed crystals are obviously increased by the present invention, which shows that the method of the present invention is effective.
Ingots produced by the above method are processed to a thickness of 0.15 mm by homogenization treatment under general conditions-hot rolling-face milling-cold rolling-solution heat treatment-cold rolling-aging heat treatment Then, a plate material was obtained, and a crystallized product in a cross section was observed. As a result, the crystallized size as shown in the above table is obtained, and it can be clearly seen that the crystallized product is reduced by the present invention.
Casting was performed at the Co and Si concentrations shown in the above table, and the plate material obtained by the above processing was subjected to a tensile test and W bending. As a result, as shown in the above table, cracks originating from the crystallized material occur due to insufficient strength in the 0.2% proof stress evaluation or W-bending, even if cast under the above condition A, except for the above concentrations. . Co and Si are in the above composition range, and casting by the casting method of the present invention can provide a thin plate for use in electrical / electronic equipment that is remarkably excellent in formability.
C43 and 44 are comparative examples of the solving means (2) term, and C45 is a comparative example of the solving means (7) term.

(Example 5)
Each alloy ingot was cast using the Cu-Ti alloy shown in the following table.

As a result, the equiaxed crystal size and the equiaxed crystal ratio of the solidified structure as shown in the above table are obtained, and the fine equiaxed crystals are obviously increased by the present invention, which shows that the method of the present invention is effective.
Ingots produced by the above method are processed to a thickness of 0.15 mm by homogenization treatment under general conditions-hot rolling-face milling-cold rolling-solution heat treatment-cold rolling-aging heat treatment Then, a plate material was obtained, and a crystallized product in a cross section was observed. As a result, the crystallized size as shown in the above table is obtained, and it can be clearly seen that the crystallized product is reduced by the present invention.
Casting was performed at the Ti concentration shown in the above table, and the plate material obtained by the above processing was subjected to a tensile test and W bending. As a result, as shown in the above table, cracks originating from the crystallized material occur due to insufficient strength in the 0.2% proof stress evaluation or W-bending, even if cast under the above condition A, except for the above concentrations. . Ti is in the above composition range, and casting by the casting method of the present invention can provide a thin plate for electrical / electronic equipment that is remarkably excellent in molding processability.
C53 and 55 are comparative examples of the solving means (2) term, and C54 is a comparative example of the solving means (7) term.

Claims (7)

A copper alloy ingot in which the equiaxed crystal area ratio represented by the following formula in the metal structure of the ingot cross-section is 70% or more, and the crystal grain size of the equiaxed crystal is 5 mm or less, and the following A to A copper alloy sheet produced from a copper alloy ingot having a composition of any of E.
Equiaxial crystal area ratio = equiaxed crystal area in the ingot cross section / ingot cross section area x 100 (%)
<A> Ni: 2.0 to 6.0% by mass
Si: 0.3-2.0 mass%
The balance is Cu and inevitable impurities
<B> Sn: 3.0 to 11.0% by mass
P: 0.03-0.30 mass%
The balance is Cu and inevitable impurities
<C> Fe: 0.1 to 2.5% by mass
P: 0.01-0.10 mass%
The balance is Cu and inevitable impurities
<D> Co: 0.5 to 2.0% by mass
Si: 0.10 to 0.55 mass%
The balance is Cu and inevitable impurities
<E> Ti: 0.1 to 3.5% by mass
The balance is Cu and inevitable impurities 2. The copper alloy material according to claim 1 , wherein the copper alloy material is composed of the component composition A, and the size of a crystallized substance mainly composed of Ni and Si present in the structure is 5 [mu] m or less. Board material. 2. The copper alloy sheet according to claim 1 , wherein the copper alloy sheet is composed of the component composition C, and the size of a crystallized substance containing Fe as a main component in the structure is 10 μm or less. A copper alloy material consisting of the component composition D, according to claim 1, wherein the size of the crystallized substances mainly composed of Co and Si present in the tissue is 1.2μm or less Copper alloy sheet. 2. The copper alloy material according to claim 1 , wherein the copper alloy material is composed of the component composition E, and the size of a crystallized substance mainly composed of Ti present in the structure is 3.0 μm or less. Board material. A method for producing a copper ingot having a composition of any one of the following A to E, wherein when a copper alloy is continuously cast, the temperature of the molten copper alloy is added to the liquidus temperature by 150 ° C. The following range, stirring and solidifying at a flow velocity of 60 to 3000 mm / sec, the equiaxed crystal area ratio represented by the following formula in the metal structure of the cast ingot cross section is 70% or more, and the crystal grains of the equiaxed crystal A method for producing a copper alloy ingot, wherein the diameter is 5 mm or less.
Equiaxial crystal area ratio = equiaxed crystal area in the ingot cross section / ingot cross section area x 100 (%)
<A> Ni: 2.0 to 6.0% by mass
Si: 0.3-2.0 mass%
The balance is Cu and inevitable impurities
<B> Sn: 3.0 to 11.0% by mass
P: 0.03-0.30 mass%
The balance is Cu and inevitable impurities
<C> Fe: 0.1 to 2.5% by mass
P: 0.01-0.10 mass%
The balance is Cu and inevitable impurities
<D> Co: 0.5 to 2.0% by mass
Si: 0.10 to 0.55 mass%
The balance is Cu and inevitable impurities
<E> Ti: 0.1 to 3.5% by mass
The balance is Cu and inevitable impurities The method for producing an ingot according to claim 6 , wherein a hot top portion made of a refractory material or a heat insulating material is provided on an upper part of the continuous casting mold.