JP2005113259A - Cu alloy and method for producing the same - Google Patents

Abstract

[Problem] To provide a Cu alloy that does not contain elements harmful to the environment such as Be, and has various properties such as conductivity, tensile strength, and high-temperature strength.
[Means for solving] (1) The number per unit area of precipitates and inclusions containing 1% or more of Cr, Ti and Zr by mass%, the balance being Cu and impurities, and the grain size being 10 μm or more. 100 / mm ² or less is Cu alloy in total. Instead of a part of Cu, one or more of Ag, P and the like, Mg and the like may be contained. This Cu alloy is obtained by melting and casting, and cooling at a cooling rate of 0.5 ° C./s or more at least in the temperature range from the slab temperature immediately after casting to 450 ° C. After this cooling, after processing in a temperature range of 450 ° C. or lower, it is desirable to subject to a heat treatment that is held in a temperature range of 280 to 550 ° C. for 10 minutes to 72 hours, and it is more desirable to perform this processing and heat treatment a plurality of times.
[Selection figure] None

Description

  The present invention relates to a Cu alloy that does not contain elements that adversely affect the environment, such as Pb, Cd, and Be, and a method for producing the same. Applications of this Cu alloy include electrical and electronic parts and safety tools.

  The following are mentioned as an electrical / electronic component. In the electronics field, there are PC connectors, semiconductor sockets, optical pickups, coaxial connectors, IC checker pins, and the like. In the communication field, mobile phone parts (connectors, battery terminals, antenna parts), submarine repeater cases, exchange connectors, and the like can be given. In the automotive field, various electrical components such as relays, various switches, micromotors, diaphragms, various terminals and the like can be mentioned. In the aerospace field, there are aircraft landing gears. In the medical / analytical instrument field, there are medical connectors, industrial connectors, and the like. In the home appliance field, relays for home appliances such as air conditioners, optical pickups for game machines, card media connectors, and the like can be given.

  Examples of safety tools include tools such as excavation rods, spanners, chain blocks, hammers, drivers, pliers, and nippers that are used in places where there is a risk of being ignited from sparks and exploding, such as ammunition stores and coal mines.

  Conventionally, Cu-Be alloys aimed at strengthening by aging precipitation of Be are known as Cu alloys used in the above-mentioned electrical and electronic parts. This alloy is widely used as a spring material and the like because of its excellent tensile strength and electrical conductivity. However, Be oxide is produced in the manufacturing process of Cu-Be alloy and in the process of processing this alloy into various parts.

  Be is a substance harmful to the environment next to Pb and Cd. For this reason, in the manufacture and processing of the Cu alloy, it is necessary to provide a treatment process for Be oxide, which increases the manufacturing cost and causes a problem in the recycling process of electric and electronic parts. Thus, Cu-Be alloys are problematic materials in light of environmental issues. For this reason, the appearance of a material that does not contain an element harmful to the environment such as Pb, Cd, and Be and that has both excellent tensile strength and conductivity is expected.

  Originally, it is difficult to simultaneously increase the tensile strength [TS (MPa)] and the conductivity [relative value to the conductivity of pure copper polycrystalline material, IACS (%)]. For this reason, many user requests place importance on one of the characteristics. This is also shown, for example, in Non-Patent Document 1 in which various characteristics of the actually produced copper products are described.

  FIG. 1 is a summary of the relationship between the tensile strength and electrical conductivity of Cu alloys described in Non-Patent Document 1 that do not contain harmful elements such as Be. As shown in FIG. 1, a conventional Cu alloy not containing a harmful element such as Be has a tensile strength as low as about 250 to 650 MPa and a tensile strength of 700 MPa or more in a region where the conductivity is 60% or more. In the region, its conductivity is as low as less than 20%. As described above, most conventional Cu alloys have high performance only in one of tensile strength (MPa) and electrical conductivity (%). Moreover, none has a high strength with a tensile strength of 1 GPa or more.

For example, Patent Document 1 proposes a Cu alloy in which Ni ₂ Si, which is called a Corson system, is precipitated. This Corson alloy has a tensile strength of 750 to 820 MPa and an electrical conductivity of about 40%. Among alloys that do not contain elements harmful to the environment such as Be, the balance between tensile strength and electrical conductivity is relatively high. Is good.

However, this alloy has limitations in increasing strength and conductivity, and problems remain in terms of product variations as described below. This alloy has age hardenability due to precipitation of Ni ₂ Si. And if Ni and Si content are reduced and electrical conductivity is raised, tensile strength will fall remarkably. On the other hand, even if Ni and Si are increased in order to increase the precipitation amount of Ni ₂ Si, there is a limit to the increase in tensile strength, and the conductivity is remarkably decreased. For this reason, the Corson-based alloy has a poor balance between the tensile strength and the electrical conductivity in the region where the tensile strength is high and the region where the electrical conductivity is high, resulting in narrow product variations. This is due to the following reason.

The electrical resistance (or the reciprocal conductivity) of the alloy is determined by electron scattering, and varies greatly depending on the type of element dissolved in the alloy. Ni dissolved in the alloy remarkably increases the electrical resistance value (remarkably decreases the electrical conductivity). Therefore, in the above Corson alloy, the electrical conductivity decreases when the Ni content is increased. On the other hand, the tensile strength of Cu alloy is obtained by age hardening. The tensile strength increases as the amount of precipitate increases and as the precipitate is finely dispersed. In the case of a Corson alloy, since the precipitated particles are only Ni ₂ Si, there is a limit to increasing the strength in terms of both the amount of precipitation and the state of dispersion.

  Patent Document 2 discloses a Cu alloy having a good wire bonding property that includes elements such as Cr and Zr and has specified surface hardness and surface roughness. As described in the examples, this Cu alloy is manufactured on the premise of hot rolling and solution treatment.

  However, in order to perform hot rolling, it is necessary to clean the surface for preventing hot cracking and removing scales, and the yield decreases. Moreover, since it is often heated in the atmosphere, active additive elements such as Si, Mg, Al and the like are easily oxidized. For this reason, there are many problems such as the generated coarse internal oxide causes the characteristic deterioration of the final product. Furthermore, enormous energy is required for hot rolling and solution treatment. Thus, since the Cu alloy described in the cited document 2 is premised on hot working and solution treatment, there are problems from the viewpoints of reduction in manufacturing cost and energy saving, and generation of coarse oxides. As a result, product characteristics (such as bending workability and fatigue properties as well as tensile strength and electrical conductivity) deteriorate.

2, 3 and 4 are a Ti—Cr binary phase diagram, a Cr—Zr binary phase diagram and a Zr—Ti binary phase diagram, respectively. As is clear from these figures, in Cu alloys containing Ti, Cr, or Zr, Ti-Cr, Cr-Zr, or Zr-Ti compounds are likely to form at high temperatures after solidification, and these compounds are precipitation strengthened. Cu ₄ Ti, Cu ₉ Zr ₂ , ZrCr ₂ , metal Cr, or metal Zr, which are effective for preventing the fine precipitation of metal. In other words, in the case of a Cu alloy manufactured through a hot process such as hot rolling, only a material having insufficient precipitation strengthening and poor ductility and toughness can be obtained. For this reason as well, the Cu alloy described in Patent Document 2 has a problem in product characteristics.

  On the other hand, the material for the safety tool is required to have mechanical properties comparable to tool steel, for example, strength and wear resistance, and does not generate a spark that causes an explosion, that is, has excellent spark resistance. Is required. For this reason, Cu alloys having high thermal conductivity, especially Cu-Be alloys aimed at strengthening by aging precipitation of Be, have been frequently used as safety tool materials. As described above, the Cu—Be alloy is a material with many environmental problems, but nevertheless, the Cu—Be alloy has been frequently used as a material for safety tools for the following reason.

FIG. 5 is a diagram showing the relationship between the conductivity [IACS (%)] and the thermal conductivity [TC (W / m · K)] of the Cu alloy. As shown in FIG. 5, both have a 1: 1 relationship, and increasing the conductivity [IACS (%)] increases the thermal conductivity [TC (W / m · K)], in other words, fire resistance. It is none other than enhancing flower development. When a rapid force due to impact or the like is applied during use of the tool, a spark is generated because a specific component in the alloy is burned by heat generated by impact or the like. As described in Non-Patent Document 2, since the thermal conductivity of steel is as low as 1/5 or less of that of Cu, local temperature rise is likely to occur. Since steel contains C, a reaction of “C + O ₂ → CO ₂ ” is caused to generate a spark. In fact, it is known that pure iron containing no C does not generate sparks. Ti or Ti alloys are more likely to generate sparks with other metals. This is because the thermal conductivity of Ti is extremely low, 1/20 that of Cu, and the reaction of “Ti + O ₂ → TiO ₂ ” occurs. FIG. 5 is a summary of the data shown in Non-Patent Document 1.

  However, as described above, electrical conductivity [IACS (%)] and tensile strength [TS (MPa)] are in a trade-off relationship, and it is extremely difficult to increase both at the same time. This is because there was no Cu alloy other than the above-mentioned Cu-Be alloy having a sufficiently high thermal conductivity TC while having a high tensile strength.

Japanese Patent No. 2572042

Japanese Patent No. 2714561 Copper Products Data Book, August 1, 1997, published by Japan Copper and Brass Association, pages 328-355 Industrial Heating, Vol.36, No.3 (1999), published by Japan Industrial Furnace Association, page 59

  The first object of the present invention is a Cu alloy which does not contain elements harmful to the environment such as Be, has a wide variety of products, is excellent in high-temperature strength and workability, and is required for materials for safety tools. The object is to provide a Cu alloy having excellent performance, that is, thermal conductivity, wear resistance, and spark resistance. The second object of the present invention is to provide a method for producing the above Cu alloy.

“Product variation is abundant” means that the balance between conductivity and tensile strength is as high as or higher than that of Be-added Cu alloys by finely adjusting the addition amount and / or manufacturing conditions. This means that it can be adjusted to a level as low as that of Cu alloys.

  “The balance between conductivity and tensile strength is at the same level as or higher than that of the Be-added Cu alloy” specifically means a state satisfying the following expression (a). Hereinafter, this state is referred to as “a state where the balance between tensile strength and electrical conductivity is extremely good”.

TS ≧ 648.06 + 985.48 × exp (−0.0513 × IACS) (a)
However, TS in the formula (a) means tensile strength (MPa), and IACS means conductivity (%).

  In addition to the above-described tensile strength and conductivity characteristics, Cu alloys are also required to have a certain high temperature strength. This is because, for example, connector materials used in automobiles and computers may be exposed to an environment of 200 ° C. or higher. When pure Cu is heated to 200 ° C or higher, the room temperature strength is greatly reduced and the desired spring characteristics can no longer be maintained. However, the above Cu-Be alloys and Corson alloys have been heated to 400 ° C. However, the room temperature strength hardly decreases.

  Therefore, the high temperature strength is aimed to be the same level as that of Cu-Be based alloys. Specifically, a heating temperature at which the rate of decrease in hardness before and after the heating test is 50% is defined as a heat resistant temperature, and a heat resistant temperature of 400 ° C. or higher is excellent in high temperature strength. A more preferable heat resistant temperature is 500 ° C. or higher.

  The target for bending workability is to be equal to or higher than that of Cu-Be alloys. Specifically, the test piece is subjected to a 90 ° bending test with various radii of curvature, and the minimum radius of curvature R at which cracking does not occur is measured, and the ratio B (= R / t) of this to the thickness t Bending workability can be evaluated. The range where the bending workability is good is that the plate material having a tensile strength TS of 800 MPa or less satisfies B ≦ 2.0, and the plate material having a tensile strength TS exceeding 800 MPa satisfies the following formula (b).

B ≦ 41.2686−39.4583 × exp [− {(TS−615.675) /2358.08} ² ] (b)

  In addition to the properties of tensile strength TS and conductivity IACS as described above, wear resistance is also required for Cu alloys as safety tools. Therefore, it aims at the level equivalent to tool steel also about abrasion resistance. Specifically, the wear resistance is excellent when the hardness at room temperature is 250 or more in terms of Vickers hardness.

  The gist of the present invention is a Cu alloy shown in the following (1) and a method for producing a Cu alloy shown in the following (2).

(1) By mass%, containing two or more selected from Cr: 0.1-4.0%, Ti: 0.1-5.0% and Zr: 0.1-5.0%, with the balance consisting of Cu and impurities, in the alloy A Cu alloy characterized in that the total number of precipitates and inclusions present in 1 is 100 / mm ^{2 in} total with a particle size of 10 μm or more.

  This Cu alloy may contain one or more components selected from at least one of the following (a), (b), (c) and (d) instead of a part of Cu. In particular, this alloy desirably has a crystal grain size of 0.01 to 35 μm.

(a) Ag: 0.1-5.0%
(b) 5.0% or less in total of at least one component selected from at least one of the following groups 1 to 3;
Group 1: 0.001 to 0.5% P and B by mass%
Second group: 0.01% to 5.0% Sn, Mn, Fe, Co, Al, Si, Nb, Ta, Mo, V, W and Ge, respectively, by mass%
Third group: 0.01% to 3.0% by mass of Zn, Ni, Te and Se, respectively
(c) 0.001 to 2.0% in total of at least one selected from Mg, Li, Ca and rare earth elements,
(d) One or more selected from Bi, Tl, Rb, Cs, Sr, Ba, Tc, Re, Os, Rh, In, Pd, Po, Sb, Hf, Au and Ga in a total amount of 0.001 to 0.3%.

(2) The slab obtained by melting and casting the Cu alloy having the chemical composition described in (1) above is at least 0.5 ° C./s in the temperature range from the slab temperature immediately after casting to 450 ° C. A Cu alloy having a total number of particles per unit area of 100 μm / mm ² or less of precipitates and inclusions present in the alloy having a particle size of 10 μm or more, characterized by cooling at the above cooling rate Manufacturing method.

  After the above cooling, it is desirable to perform processing in a temperature range of 450 ° C. or lower, or further, heat treatment for holding in a temperature range of 280 to 550 ° C. for 10 minutes to 72 hours. The processing in the temperature range of 450 ° C. or lower and the heat treatment held in the temperature range of 280 to 550 ° C. for 10 minutes to 72 hours may be performed a plurality of times. Further, after the final heat treatment, processing in a temperature range of 450 ° C. or lower may be performed.

In the present invention, the precipitate is, for example, Cu ₄ Ti, Cu ₉ Zr ₂ , ZrCr ₂ , metal Cr, metal Zr, metal Ag or the like, and the inclusion is, for example, Cr—Ti compound, Ti—Zr compound or Zr. -Cr compounds, metal oxides, metal carbides, metal nitrides and the like.

  Embodiments of the present invention will be described below. In the following description, “%” for the content of each element means “mass%”.

1. About the Cu alloy of the present invention
(A) Chemical composition One of the Cu alloys of the present invention contains two or more selected from Cr: 0.01 to 4.0%, Ti: 0.01 to 5.0% and Zr: 0.01 to 5.0%, and the balance Has a chemical composition consisting of Cu and impurities.

Cr: 0.01-4.0%
If the Cr content is less than 0.01%, the strength becomes insufficient, and an alloy having a good balance between strength and electrical conductivity cannot be obtained even if Ti or Zr is contained in an amount of 0.01% or more. In particular, in order to obtain a state in which the balance between tensile strength and electrical conductivity equivalent to or higher than that of the Be-added Cu alloy is extremely good, it is desirable to contain 0.1% or more. On the other hand, if the Cr content exceeds 4.0%, metallic Cr precipitates coarsely and adversely affects bending characteristics, fatigue characteristics, and the like. Therefore, the Cr content is specified as 0.01 to 4.0%.

Ti: 0.01-5.0%
If the Ti content is less than 0.01%, sufficient strength cannot be obtained even if Cr or Zr is contained in an amount of 0.01% or more. However, if its content exceeds 5.0%, the strength increases but the conductivity deteriorates. Furthermore, Ti segregation is caused during casting, and it becomes difficult to obtain a homogeneous slab, and cracks and chips are likely to occur during subsequent processing. Therefore, the Ti content is set to 0.01 to 5.0%. As in the case of Cr, Ti is desirably contained in an amount of 0.1% or more in order to obtain a state where the balance between tensile strength and electrical conductivity is extremely good.

Zr: 0.01-5.0%
If Zr is less than 0.01%, sufficient strength cannot be obtained even if Cr or Ti is contained in an amount of 0.01% or more. However, if its content exceeds 5.0%, the strength increases but the conductivity deteriorates. Moreover, since Zr segregation is caused during casting, and it becomes difficult to obtain a homogeneous slab, cracks and chips are likely to occur during subsequent processing. Therefore, the Zr content is set to 0.01 to 5.0%. As in the case of Cr, Zr is preferably contained in an amount of 0.1% or more in order to obtain a state where the balance between tensile strength and electrical conductivity is extremely good.

  The Cu alloy of the present invention preferably has the chemical components described above and contains 0.1 to 5.0% Ag instead of a part of Cu.

Ag is an element that hardly deteriorates conductivity even when dissolved in a Cu matrix. Moreover, metal Ag raises an intensity | strength by fine precipitation. When added simultaneously with two or more selected from Cr, Ti and Zr, finer precipitates such as Cu ₄ Ti, Cu ₉ Zr ₂ , ZrCr ₂ , metal Cr, metal Zr or metal Ag contribute to precipitation hardening. Has the effect of precipitating. This effect becomes prominent at 0.1% or more, but when it exceeds 5.0%, it becomes saturated and causes an increase in the cost of the alloy. Therefore, the Ag content is desirably 0.1 to 5.0%. More desirable is 2.0% or less.

  In order to improve corrosion resistance and heat resistance, the Cu alloy of the present invention is replaced with a part of Cu, and one or more components selected from at least one of the following first group to third group It is desirable to contain 5.0% or less in total.

Group 1: 0.001 to 0.5% P and B by mass%
Second group: 0.01% to 5.0% Sn, Mn, Fe, Co, Al, Si, Nb, Ta, Mo, V, W and Ge, respectively, by mass%
Third group: 0.01% to 3.0% by mass of Zn, Ni, Te and Se, respectively

  Any of these elements is an element having an effect of improving corrosion resistance and heat resistance while maintaining a balance between strength and conductivity. This effect is achieved by 0.001% or more of P and B, and 0.01% or more of Sn, Mn, Fe, Co, Al, Si, Nb, Ta, Mo, V, W, Ge, Zn, Ni, Te, Se, respectively. And when Sr is contained. However, when these contents are excessive, the conductivity decreases. Therefore, when these elements are contained, P and B are 0.001 to 0.5%, Sn, Mn, Fe, Co, Al, Si, Nb, Ta, Mo, V, W and Ge are 0.01 to 5.0%. Zn, Ni, Te and Se are desirably 0.01 to 3.0%. In particular, since Sn contributes to high strength by finely depositing an intermetallic compound of Ti—Sn, it is preferable to actively use it.

  Furthermore, even if the content of these elements is within the above range, if the total amount exceeds 5.0%, the conductivity deteriorates. Accordingly, when one or more of the above elements are contained, the total amount must be limited to 5.0% or less. A desirable range is 0.01 to 2.0%.

  The Cu alloy of the present invention contains 0.001 to 2.0% in total of at least one selected from Mg, Li, Ca and rare earth elements instead of a part of Cu for the purpose of increasing the high temperature strength. desirable. Hereinafter, these are also referred to as “fourth group elements”.

  Mg, Li, Ca and rare earth elements are elements that combine with oxygen atoms in the Cu matrix to form fine oxides and increase high temperature strength. The effect becomes remarkable when the total content of these elements is 0.001% or more. However, if the content exceeds 2.0%, the above effects are saturated, and there are problems such as a decrease in electrical conductivity and a deterioration in bending workability. Therefore, the total content when one or more selected from Mg, Li, Ca and rare earth elements is contained is preferably 0.001 to 2.0%. In addition, rare earth elements mean Sc, Y, and a lanthanoid, and the simple substance of each element may be added and a misch metal may be added.

  The Cu alloy of the present invention is replaced with Bi, Tl, Rb, Cs, Sr, Ba, Tc instead of a part of Cu for the purpose of widening the width (ΔT) of the liquidus and solidus at the time of casting of the alloy. It is desirable to contain 0.001 to 0.3% in total of at least one selected from among Re, Os, Rh, In, Pd, Po, Sb, Hf, Au, and Ga. Hereinafter, these are also referred to as “fifth group elements”.

  All of these elements have the effect of lowering the solidus and expanding ΔT. If this width ΔT is widened, it is possible to secure a certain time from casting to solidification, so that casting becomes easy, but if ΔT is too wide, the yield strength in the low temperature range is reduced, and cracking occurs at the end of solidification. So-called solder brittleness occurs. For this reason, ΔT is preferably in the range of 50 to 200 ° C.

C, N and O are elements usually contained as impurities. These elements form carbides, nitrides and oxides with the metal elements in the alloy. If these precipitates or inclusions are fine, the strengthening of the alloy, particularly the high-temperature strength, as in the case of the precipitates such as Cu ₄ Ti, Cu ₉ Zr ₂ , ZrCr ₂ , metal Cr, metal Zr or metal Ag described later. There is an action to raise. However, if each of these elements exceeds 1%, coarse precipitates or inclusions are formed, and ductility is reduced. Therefore, it is preferable to limit each to 1% or less. More preferred is 0.1% or less.

(B) Regarding the total number of precipitates and inclusions In the Cu alloy of the present invention, the total number of precipitates and inclusions present in the alloy having a particle size of 10 μm or more per unit area is 100 / It must be ² mm or less.

In the Cu alloy of the present invention, Cu ₄ Ti, Cu ₉ Zr ₂ , ZrCr ₂ , metal Cr, metal Zr, or metal Ag can be finely precipitated, whereby the strength can be improved without lowering the conductivity. These increase the strength by precipitation hardening. The dissolved Cr, Ti, and Zr are reduced by precipitation, and the conductivity of the Cu matrix approaches that of pure Cu.

However, if the grain size of Cu ₄ Ti, Cu ₉ Zr ₂ , ZrCr ₂ , metal Cr, metal Zr, metal Ag, Cr-Ti compound, Ti-Zr compound or Zr-Cr compound precipitates coarsely as 10μm or more, ductility For example, cracks and chips are likely to occur during bending or punching when processing the connector. In addition, fatigue characteristics and impact resistance characteristics may be adversely affected during use. In particular, when a coarse Ti—Cr compound is produced during cooling after solidification, cracks and chips are likely to occur in subsequent processing steps. In addition, since the hardness increases too much in the aging treatment process, Cu ₄ Ti, Cu ₉ Zr ₂ , ZrCr ₂ , metal Cr, metal Zr or metal Ag is prevented from being finely precipitated, making it impossible to increase the strength of the Cu alloy. . Such a problem becomes prominent when the total number of precipitates and inclusions present in the alloy having a particle size of 10 μm or more per unit area is less than 100 / mm ² .

For this reason, in the present invention, it is stipulated as an essential requirement that the total number of precipitates and inclusions present in the alloy having a particle size of 10 μm or more per unit area is 100 pieces / mm ² or less in total. The desirable number is 50 pieces / mm ² or less, and more desirably 10 pieces / mm ² or less. In addition, these particle sizes and numbers can be obtained by the method shown in the examples.

(C) About crystal grain size
If the crystal grain size of the Cu alloy is made fine, it is advantageous for increasing the strength and also improves the ductility and the bending workability. However, when the crystal grain size is less than 0.01 μm, the high-temperature strength tends to decrease, and when it exceeds 35 μm, the ductility decreases. Therefore, the crystal grain size is desirably 0.01 to 35 μm.

2. About the manufacturing method of the Cu alloy of the present invention In the Cu alloy of the present invention, Cu ₄ Ti, Cu ₉ Zr ₂ , ZrCr ₂ , metal Cr, metal Zr or Cr-Ti compound that prevents fine precipitation of metal Ag, Ti-Zr Inclusions such as compounds and Zr—Cr compounds are likely to form immediately after solidification of the slab. Even if such inclusions are subjected to a solution treatment after casting and raising the solution temperature, it is difficult to make them solid. The solution treatment at a high temperature only causes aggregation and coarsening of inclusions.

Therefore, in the method for producing a Cu alloy of the present invention, a slab obtained by melting and casting a Cu alloy having the above chemical composition is at least in a temperature range from a slab temperature immediately after casting to 450 ° C. By cooling at a cooling rate of 0.5 ° C./s or more, the total number of precipitates and inclusions present in the alloy having a particle size of 10 μm or more per unit area is 100 pieces / mm ² or less. It was decided.

  After this cooling, it is desirable to process in a temperature range of 450 ° C. or lower, or to be subjected to heat treatment for 10 minutes to 72 hours in the temperature range of 280 to 550 ° C. after this processing. It is further desirable to perform a plurality of times of processing in a temperature range of 450 ° C. or lower and heat treatment holding in a temperature range of 280 to 550 ° C. for 10 minutes to 72 hours. You may perform said process after the last heat processing.

(A) Cooling rate at least in the temperature range from slab temperature immediately after casting to 450 ℃: 0.5 ℃ / s or more
Inclusions such as Cr—Ti compound, Ti—Zr compound, Zr—Cr compound, Cu ₄ Ti, Cu ₉ Zr ₂ , ZrCr ₂ , metal Cr, metal Zr, or metal Ag are formed in a temperature range of 280 ° C. or higher. In particular, when the cooling rate in the temperature range from slab temperature immediately after casting to 450 ° C. is slow, inclusions such as Cr—Ti compound, Ti—Zr compound, Zr—Cr compound are generated coarsely, and the particle size is reduced. It may reach 10 μm or more and even several hundred μm. Further, Cu ₄ Ti, Cu ₉ Zr ₂ , ZrCr ₂ , metal Cr, metal Zr or metal Ag is also coarsened to 10 μm or more. In such a state where coarse precipitates and inclusions are generated, there is a possibility that cracks and breaks may occur during subsequent processing, as well as Cu ₄ Ti, Cu ₉ Zr ₂ , ZrCr ₂ , metal in the aging process The precipitation hardening effect of Cr, metal Zr or metal Ag is impaired, and the strength of the alloy cannot be increased. Therefore, at least in this temperature range, it is necessary to cool the slab at a cooling rate of 0.5 ° C./s or more. The higher the cooling rate, the better. The preferable cooling rate is 2 ° C./s or more, and more preferably 10 ° C./s or more.

(B) Processing temperature after cooling: temperature range of 450 ° C. or less In the Cu alloy production method of the present invention, the cast slab is cooled under predetermined conditions and then hot rolled or solutionized. Without passing through a hot process such as processing, the final product is reached only by a combination of processing and aging heat treatment.

Processing such as rolling and drawing may be performed at 450 ° C. or lower. For example, when continuous casting is employed, these processes may be performed in the cooling process after solidification. When processing at a temperature exceeding 450 ° C, Cu ₄ Ti, Cu ₉ Zr ₂ , ZrCr ₂ , metal Cr, metal Zr or metal Ag precipitates coarsely during processing, resulting in ductility, impact resistance and fatigue of the final product. Degrading properties. Also, if the above precipitates are coarsely deposited during processing, Cu ₄ Ti, Cu ₉ Zr ₂ , ZrCr ₂ , metal Cr, metal Zr or metal Ag cannot be finely precipitated by aging treatment, and the Cu alloy Strengthening is insufficient.

The lower the processing temperature, the higher the dislocation density during processing, so that Cu ₄ Ti, Cu ₉ Zr ₂ , ZrCr ₂ , metal Cr, metal Zr or metal Ag, etc. can be precipitated more finely in the subsequent aging treatment. Can do. For this reason, higher strength can be imparted to the Cu alloy. Therefore, a preferable processing temperature is 250 ° C. or lower, and more preferably 50 ° C. or lower. It may be 25 ° C or lower.

  Note that the processing in the above temperature range is desirably performed at a processing rate (cross-sectional reduction rate) of 20% or more. More preferred is 50% or more. If processing is performed at such a processing rate, the dislocations introduced thereby become precipitation nuclei during the aging treatment, resulting in finer precipitates and shortening the time required for precipitation, which is harmful to conductivity. Reduction of solid solution elements can be realized at an early stage.

(C) Aging treatment conditions: Hold for 10 minutes to 72 hours in a temperature range of 280 to 550 ° C. Aging treatment is performed by precipitating Cu ₄ Ti, Cu ₉ Zr ₂ , ZrCr ₂ , metal Cr, metal Zr or metal Ag. It is effective in increasing the strength of Cu alloy and improving the conductivity by reducing solid solution elements (Cr, Ti, etc.) that adversely affect the conductivity. However, when the treatment temperature is lower than 280 ° C., it takes a long time to diffuse the precipitated elements, and the productivity is lowered. On the other hand, when the treatment temperature exceeds 550 ° C., the precipitate becomes too coarse, and not only the strength cannot be increased by the precipitation hardening action, but also the ductility, impact resistance and fatigue characteristics are lowered. For this reason, it is desirable to perform an aging treatment in the temperature range of 280-550 degreeC. A desirable aging treatment temperature is 300 to 450 ° C, and more desirably 350 to 400 ° C.

  If the aging treatment time is less than 10 minutes, a desired precipitation amount cannot be secured even if the aging treatment temperature is set high, and if it exceeds 72 hours, the treatment cost increases. Therefore, it is desirable to perform the aging treatment in the temperature range of 280 to 550 ° C. for 10 minutes to 72 hours. A typical aging time is 1 to 5 hours.

  The aging treatment is preferably performed in a reducing atmosphere, in an inert gas atmosphere, or in a vacuum of 20 Pa or less in order to prevent generation of scale due to surface oxidation. Excellent plating properties are also ensured by the treatment under such an atmosphere.

The above processing and aging treatment may be repeated as necessary. If repeated, a desired amount of precipitation can be obtained in a shorter time than in a single treatment (processing and aging treatment), and Cu ₄ Ti, Cu ₉ Zr ₂ , ZrCr ₂ , metal Cr, metal Zr or Metal Ag can be deposited more finely. At this time, for example, when the treatment is repeated twice, the second aging treatment temperature is preferably slightly lower (20-70 ° C.) than the first aging treatment temperature. The reason why such a heat treatment is performed is that when the temperature of the second aging treatment is higher, the precipitate generated during the first aging treatment becomes coarse. In the third and subsequent aging treatments, it is desirable that the temperature is lower than the aging treatment temperature performed before that, as described above.

(D) Others In the method for producing a Cu alloy of the present invention, conditions other than the above production conditions, for example, conditions such as melting and casting are not particularly limited, but may be performed as follows, for example.

  The dissolution is preferably performed in a non-oxidizing or reducing atmosphere. This is because when the amount of dissolved oxygen in the molten copper increases, so-called hydrogen disease, in which water vapor is generated and blisters are generated in the subsequent process, occurs. In addition, solid oxide elements that easily oxidize, for example, coarse oxides such as Ti and Cr, are generated, and when these remain in the final product, the ductility and fatigue characteristics are significantly reduced.

As a method for obtaining a slab, continuous casting is preferable in terms of productivity and solidification speed, but other methods such as an ingot method may be used as long as the method satisfies the above-described conditions. A preferable casting temperature is 1250 ° C. or higher. More preferred is 1350 ° C. or higher. At this temperature, Cr, Ti and Zr can be sufficiently dissolved, and inclusions such as Cr-Ti compound, Ti-Zr compound, Zr-Cr compound, Cu ₄ Ti, Cu ₉ Zr ₂ , ZrCr ₂ This is because metal Cr, metal Zr, metal Ag or the like is not generated.

  When obtaining a slab by continuous casting, a method using a graphite mold usually performed with a copper alloy is recommended from the viewpoint of lubricity. As the mold material, a refractory material that does not easily react with Ti, Cr, or Zr, which are main alloy elements, such as zirconia, may be used.

  Cu alloys having chemical compositions shown in Tables 1 to 4 were vacuum-melted in a high-frequency melting furnace and cast into a zirconia mold to a depth of 15 mm to obtain a cast piece. As the rare earth element, a simple substance of each element or misch metal was added.

  The obtained slab is cooled at a predetermined cooling rate by spray cooling in the temperature range from 900 ° C. to 450 ° C., which is the temperature immediately after casting (the temperature immediately after removal from the mold), and then the thickness is obtained by cutting and cutting. A rolled material of 10 mm × width 80 mm × length 150 mm was produced. For comparison, some of the rolling materials were subjected to solution heat treatment at 950 ° C. These rolled materials were subjected to rolling at a reduction rate of 80% at room temperature (first rolling) to obtain a plate material having a thickness of 2 mm, and subjected to aging treatment (first aging) under predetermined conditions to prepare test materials. Some test materials were further rolled at a reduction rate of 95% at room temperature (second rolling) to a thickness of 0.1 mm, and subjected to aging treatment (second aging) under predetermined conditions. These production conditions are shown in Tables 5-9. In Tables 5 to 9, examples in which the above solution treatment was performed are Comparative Examples 6, 8, 10, 12, 14, and 16.

  With respect to the test material thus prepared, the particle size of precipitates and inclusions, the total number per unit area, tensile strength, electrical conductivity, heat resistant temperature and bending workability were determined by the following method. These results are also shown in Tables 5-9.

<Total number of precipitates and inclusions>
A cross section perpendicular to the rolling surface of each specimen and parallel to the rolling direction is mirror-polished, etched with a corrosive solution in which ammonia and hydrogen peroxide are mixed at a volume ratio of 9: 1, and then 100 times with an optical microscope. A 1 mm × 1 mm field of view was observed at a magnification of. Thereafter, the value obtained by measuring the major axis of the precipitates and inclusions (the length of the straight line that can be drawn the longest in the grain under conditions that do not contact the grain boundary in the middle) is defined as the grain size. Furthermore, among the precipitates and inclusions having a particle size of 10 μm or more, the total number n _{1 is} calculated by assuming that one half crosses the frame of the 1 mm × 1 mm field and one within the frame, The average value (N / 10) of the number N (= n ₁ + n ₂ +... + N ₁₀ ) in 10 arbitrarily selected visual fields is defined as the total number of precipitates and inclusions in the sample.

<Tensile strength>
Take the 13B test piece specified in JIS Z 2201 from the above specimen so that the tensile direction and the rolling direction are parallel, and pull at room temperature (25 ° C) according to the method specified in JIS Z 2241. The strength [TS (MPa)] was determined.

<Conductivity>
Take a test piece of width 10mm × length 60mm so that the longitudinal direction and the rolling direction are parallel from the above specimen, measure the potential difference between both ends of the test piece by flowing current in the longitudinal direction of the test piece, The electrical resistance was determined by the 4-terminal method. Subsequently, the electrical resistance (resistivity) per unit volume is calculated from the volume of the test piece measured with a micrometer, and the conductivity [IACS is calculated from the ratio of the resistivity of 1.72 μΩ · cm of the standard sample annealed with polycrystalline pure copper. (%)].

<Heat-resistant temperature>
Take a test piece of width 10mm x length 10mm from the above test material, mirror-polish the cross section perpendicular to the rolling surface and parallel to the rolling direction, and press the diamond pyramid indenter into the test piece with a load of 50g The Vickers hardness defined by the ratio between the load and the surface area of the indentation was measured. Furthermore, after heating this at a predetermined temperature for 2 hours and cooling to room temperature, the Vickers hardness was measured again, and the heating temperature at which the hardness was 50% of the hardness before heating was defined as the heat resistant temperature.

<Bending workability>
Samples of width 10mm x length 60mm are sampled from the above specimens so that the longitudinal direction and the rolling direction are parallel, and the bending radius of curvature (inner diameter) is changed and a 90 ° bending test is performed. did. The bending part of the test piece after the test was observed from the outer diameter side using an optical microscope. Then, the minimum curvature radius at which no cracks occur was R, and a ratio B (= R / t) with the thickness t of the test piece was obtained.

  “Evaluation” in the column of bending workability is “○” when a plate material with a tensile strength TS of 800 MPa or less satisfies B ≦ 2.0, and a plate material with a tensile strength TS of over 800 MPa satisfies the following formula (b): The case where these were not satisfied was designated as “x”.

B ≦ 41.2686−39.4583 × exp [− {(TS−615.675) /2358.08} ² ] (b)

  FIG. 6 is a diagram showing the relationship between the tensile strength and the electrical conductivity of each example. In FIG. 6, the values of the examples of the present invention in Examples 1 and 2 are plotted.

  As shown in Tables 5 to 9 and FIG. 6, in Examples 1-141 of the present invention, the chemical composition and the total number of precipitates and inclusions are within the range defined by the present invention. The above equation (a) was satisfied. Therefore, it can be said that these alloys have a balance between electrical conductivity and tensile strength at the same level as or higher than that of the Be-added Cu alloy. Inventive Examples 121-131 are examples in which the addition amount and / or production conditions were finely adjusted in the same component system. These alloys have a relationship between tensile strength and electrical conductivity as indicated by “Δ” in FIG. 6 and can be said to be Cu alloys having conventionally known Cu alloy characteristics. Thus, it can be seen that the Cu alloy of the present invention is rich in variations in tensile strength and electrical conductivity. In addition, even at the heat resistant temperature, a high level of 500 ° C. was maintained. Furthermore, the bending characteristics were also good.

  On the other hand, Comparative Examples 1 to 4 and 17 to 23 were inferior in bending workability because the content of any one of Cr, Ti and Zr was outside the range defined in the present invention. In particular, Comparative Examples 17 to 23 had low electrical conductivity because the total content of the elements of the first group to the fifth group was also outside the range defined by the present invention.

  Comparative Examples 5 to 16 are all examples of alloys having a chemical composition defined in the present invention. However, 5, 7, 9, 11, 13, and 15 had a slow cooling rate after casting, and Comparative Examples 6, 8, 10, 12, 14, and 16 were subjected to solution treatment, and thus all were precipitates. In addition, the total number of inclusions exceeded the range defined in the present invention, and the bending workability was poor. Further, the comparative example subjected to the solution treatment is inferior in tensile strength and conductivity as compared with the alloys of the present invention having the same chemical composition (inventive examples 5, 21, 37, 39, 49 and 85).

  In Comparative Examples 2 and 23, the ear cracking was severe in the second rolling, and sample collection was impossible.

  Next, in order to investigate the influence of the process, Cu alloys having chemical compositions No. 67, 114 and 127 shown in Tables 2 to 4 were melted in a high-frequency melting furnace, and the depth was 15 mm in a ceramic mold. After obtaining a slab of thickness 15 mm × width 100 mm × length 130 mm, it was cooled at a predetermined cooling rate by spray cooling in the temperature range from 900 ° C. to 450 ° C., which is the temperature immediately after casting. Test materials were produced from the slabs under the conditions shown in Tables 10-12. About the obtained specimen, the total number of precipitates and inclusions, tensile strength, electrical conductivity, heat resistant temperature and bending workability were investigated in the same manner as described above. These results are also shown in Tables 10-12.

  As shown in Tables 10 to 12 and FIG. 6, in Examples 142 to 209 of the present invention, all of the cooling conditions, rolling conditions and aging treatment conditions are within the range defined by the present invention. A Cu alloy having a total number in the range defined by the present invention could be produced. For this reason, in all examples of the present invention, the tensile strength and the electrical conductivity satisfied the above-described formula (a). Moreover, the heat-resistant temperature was maintained at a high level and the bending workability was good.

  On the other hand, in Comparative Examples 24-38, the cooling rate, the rolling temperature, and the heat treatment temperature deviate from the scope of the present invention, so the precipitates become coarse and the precipitate distribution deviates from the scope of the present invention, and the bending workability also decreases.

  An alloy having the chemical composition shown in Table 13 was melted in a high-frequency furnace in the atmosphere and continuously cast by the following two methods. The average cooling rate from the liquidus temperature to 450 ° C. was controlled by primary cooling and secondary cooling using water spray. In each method, during melting, an appropriate amount of charcoal powder was added to the upper part of the molten metal to make the molten metal surface part a reducing atmosphere.

<Continuous casting method>
(1) In horizontal drawing, the hot metal was poured into the holding furnace, but thereafter, charcoal was added in the same manner to prevent oxidation, and a slab was obtained by intermittent drawing using a graphite mold. The average drawing speed was 200 mm / min.
(2) In the pulling method, after pouring into the tundish, the charcoal is also prevented from being oxidized, and from the tundish into the mold, continuously into the molten metal pool through a layer covered with charcoal powder by a zirconia immersion nozzle. I poured water. The casting mold was a copper alloy water-cooled casting mold with a 4 mm-thick graphite lined, and was continuously drawn at an average speed of 150 mm.

  Each cooling rate was calculated by measuring the surface after exiting the mold with several thermocouples and using it together with the heat transfer calculation.

  The obtained slab was subjected to surface grinding, and then subjected to cold rolling, heat treatment, cold rolling and heat treatment under the conditions shown in Table 14, and finally a thin strip having a thickness of 200 μm was obtained. Using the obtained ribbon, the total number of precipitates and inclusions, tensile strength, electrical conductivity, heat resistant temperature and bending workability were investigated in the same manner as described above. These results are also shown in Table 14.

  As shown in Table 14, an alloy having high tensile strength and conductivity was obtained by any casting method, and it was found that the method of the present invention can be applied to an actual casting machine.

  In order to evaluate the application to safety tools, samples were prepared by the following method, and the wear resistance (Vickers hardness) and the spark resistance were evaluated.

  The alloys shown in Table 15 were melted in a high-frequency furnace in the atmosphere and die-cast by the Darville method. That is, after holding the mold in the state shown in FIG. 7 (a) and pouring a molten metal at about 1300 ° C. into the mold while ensuring a reducing atmosphere with charcoal powder, this is shown in FIG. 7 (b). As shown, it was tilted and solidified in the state of FIG. The mold was made of cast iron with a thickness of 50 mm, and a cooling hole was drilled in the mold so that air cooling was possible. The slab was wedge-shaped for easy pouring, with a lower cross section of 30 x 300, an upper cross section of 50 x 400 mm, and a height of 700 mm.

  A portion from the lower end of the obtained slab to 300 mm was sampled and subjected to surface grinding, followed by cold rolling (30 → 10 mm) → heat treatment (375 ° C. × 16 h) to obtain a 10 mm thick plate. Using these plates, the total number of precipitates and inclusions, tensile strength, electrical conductivity, heat-resistant temperature and bending workability were investigated by the above method, and the wear resistance, thermal conductivity and fire resistance were further investigated by the following methods. The flower development was investigated. These results are also shown in Table 15.

<Abrasion resistance>
Test specimens each having a width of 10 mm and a length of 10 mm were collected from the test material, and a cross section perpendicular to the rolling surface and parallel to the rolling direction was mirror-polished and subjected to a load of 25 ° C. according to the method specified in JIS Z 2244. Vickers hardness at 9.8 N was measured.

<Thermal conductivity>
For the thermal conductivity [TC (W / m · K)], the above-mentioned conductivity [IACS (%)] was obtained from the formula “TC = 14.804 + 3.8172 × IACS” described in FIG.

<Fire resistance>
Using a table grinder with a rotational speed of 12000 rpm, a spark test was conducted in accordance with the method specified in JIS G 0566, and the presence or absence of sparks was confirmed visually.

  The average cooling rate up to 450 ° C. obtained based on the liquidus obtained from the heat transfer calculation was measured by inserting a thermocouple at a position 5 mm below the inner wall of the mold 100 mm from the lower cross section. It was ° C / s.

  As shown in Table 15, in Invention Examples 210 to 213, the wear resistance was good, the thermal conductivity was large, and no spark was observed. On the other hand, since Comparative Examples 39 and 40 did not satisfy the chemical composition defined in the present invention, the thermal conductivity was small and sparks were observed.

  According to the present invention, it is a Cu alloy that does not contain elements harmful to the environment such as Be, has abundant product variations, is excellent in high-temperature strength and workability, and is further required for materials for safety tools. Cu alloy having excellent performance, that is, thermal conductivity, wear resistance and spark resistance, and a method for producing the same can be provided.

This is a summary of the relationship between the tensile strength and conductivity of Cu alloys described in Non-Patent Document 1 that do not contain harmful elements such as Be. It is a Ti-Cr binary phase diagram. It is a Zr-Cr binary system phase diagram. It is a Ti-Zr binary system phase diagram. It is a figure which shows the relationship between electrical conductivity and thermal conductivity. It is a figure which shows the relationship between the tensile strength of each Example, and electrical conductivity. It is a schematic diagram which shows the casting method by a Darville method.

Claims (22)

Contains 2 or more selected from Cr: 0.01-4.0%, Ti: 0.01-5.0% and Zr: 0.01-5.0% by mass%, with the balance being Cu and impurities, present in the alloy A Cu alloy characterized in that the number of precipitates and inclusions having a particle size of 10 μm or more per unit area is 100 pieces / mm ² or less in total. 2% or more selected from Cr: 0.01-4.0%, Ti: 0.01-5.0% and Zr: 0.01-5.0%, and Ag: 0.1-5.0%, with the balance being Cu and impurities. Cu alloy characterized in that the total number of precipitates and inclusions present in the alloy having a particle size of 10 μm or more per unit area is 100 pieces / mm ² or less. Contains 2 or more selected from Cr: 0.01-4.0%, Ti: 0.01-5.0% and Zr: 0.01-5.0% by mass%, and from the following first group to third group Unit area of one or more components selected from at least one group in a total amount of 5.0% or less, the balance being Cu and impurities, and the precipitates and inclusions present in the alloy having a particle size of 10 μm or more Cu alloy characterized in that the total number of hits is 100 / mm ² or less.
Group 1: 0.001 to 0.5% P and B by mass%
Second group: 0.01% to 5.0% Sn, Mn, Fe, Co, Al, Si, Nb, Ta, Mo, V, W and Ge, respectively, by mass%
Third group: 0.01% to 3.0% by mass of Zn, Ni, Te and Se, respectively 2% or more selected from Cr: 0.01-4.0%, Ti: 0.01-5.0% and Zr: 0.01-5.0%, and Ag: 0.1-5.0% in mass%, and also the following 1st A total of 5.0% or less of at least one component selected from at least one group from the group to the third group, with the balance consisting of Cu and impurities, and grains of precipitates and inclusions present in the alloy A Cu alloy characterized in that the number per unit area of those having a diameter of 10 μm or more is 100 pieces / mm ² or less in total.
Group 1: 0.001 to 0.5% P and B by mass%
Second group: 0.01% to 5.0% Sn, Mn, Fe, Co, Al, Si, Nb, Ta, Mo, V, W and Ge, respectively, by mass%
Third group: 0.01% to 3.0% by mass of Zn, Ni, Te and Se, respectively Contains 2 or more selected from Cr: 0.01-4.0%, Ti: 0.01-5.0% and Zr: 0.01-5.0% by mass%, and further selected from Mg, Li, Ca and rare earth elements One or more of these are included in a total of 0.001 to 2.0%, the balance is made of Cu and impurities, and the number of precipitates and inclusions present in the alloy having a particle size of 10 μm or more per unit area is 100 in total. Cu alloy, characterized in that it is ² pieces / mm ² or less. 2% or more selected from Cr: 0.01-4.0%, Ti: 0.01-5.0% and Zr: 0.01-5.0%, and Ag: 0.1-5.0% by mass%, and further Mg, Li, Units containing at least one element selected from Ca and rare earth elements in a total amount of 0.001 to 2.0%, the balance being Cu and impurities, and the precipitates and inclusions present in the alloy having a particle size of 10 μm or more Cu alloy characterized in that the total number per area is 100 / mm ² or less. 2% or more selected from Cr: 0.01-4.0%, Ti: 0.01-5.0% and Zr: 0.01-5.0% by mass%, and at least of the following 1st group to 3rd group One or more components selected from one group are included in a total amount of 5.0% or less, and one or more components selected from Mg, Li, Ca and rare earth elements are included in a total amount of 0.001 to 2.0%, with the balance being Cu. And a total number of precipitates / inclusions in the alloy having a particle size of 10 μm or more per unit area of 100 / mm ² or less.
Group 1: 0.001 to 0.5% P and B by mass%
Second group: 0.01% to 5.0% Sn, Mn, Fe, Co, Al, Si, Nb, Ta, Mo, V, W and Ge, respectively, by mass%
Third group: 0.01% to 3.0% by mass of Zn, Ni, Te and Se, respectively 2% or more selected from Cr: 0.01-4.0%, Ti: 0.01-5.0% and Zr: 0.01-5.0%, and Ag: 0.1-5.0% by mass%, the following 1st group To at least one of the components selected from at least one of the three groups to 5.0% or less in total, and one or more selected from Mg, Li, Ca and rare earth elements in total 0.001 -2.0% inclusive, the balance consisting of Cu and impurities, the total number of precipitates and inclusions in the alloy with a particle size of 10 μm or more per unit area is 100 pieces / mm ² or less Characteristic Cu alloy.
Group 1: 0.001 to 0.5% P and B by mass%
Second group: 0.01% to 5.0% Sn, Mn, Fe, Co, Al, Si, Nb, Ta, Mo, V, W and Ge, respectively, by mass%
Third group: 0.01% to 3.0% by mass of Zn, Ni, Te and Se, respectively 2% or more selected from Cr: 0.01-4.0%, Ti: 0.01-5.0% and Zr: 0.01-5.0%, and Bi, Tl, Rb, Cs, Sr, Ba, Tc, Contains at least 0.001 to 0.3% of one or more selected from Re, Os, Rh, In, Pd, Po, Sb, Hf, Au, and Ga, with the balance being Cu and impurities, present in the alloy A Cu alloy characterized in that the number of precipitates and inclusions having a particle size of 10 μm or more per unit area is 100 pieces / mm ² or less in total. 2% or more selected from Cr: 0.01-4.0%, Ti: 0.01-5.0% and Zr: 0.01-5.0%, and Ag: 0.1-5.0%, and Bi, Tl, One or more selected from Rb, Cs, Sr, Ba, Tc, Re, Os, Rh, In, Pd, Po, Sb, Hf, Au, and Ga are included in a total amount of 0.001 to 0.3%, and the balance is Cu. And a total number of precipitates / inclusions in the alloy having a particle size of 10 μm or more per unit area of 100 / mm ² or less. Contains 2 or more selected from Cr: 0.01-4.0%, Ti: 0.01-5.0% and Zr: 0.01-5.0% by mass%, and from the following first group to third group One or more components selected from at least one group are included in a total amount of 5.0% or less, and Bi, Tl, Rb, Cs, Sr, Ba, Tc, Re, Os, Rh, In, Pd, Po, Sb, One or more selected from Hf, Au and Ga is contained in a total amount of 0.001 to 0.3%, the balance is made of Cu and impurities, and the precipitates and inclusions present in the alloy have a particle size of 10 μm or more. A Cu alloy characterized in that the total number per unit area is 100 / mm ² or less.
Group 1: 0.001 to 0.5% P and B by mass%
Second group: 0.01% to 5.0% Sn, Mn, Fe, Co, Al, Si, Nb, Ta, Mo, V, W and Ge, respectively, by mass%
Third group: 0.01% to 3.0% by mass of Zn, Ni, Te and Se, respectively 2% or more selected from Cr: 0.01-4.0%, Ti: 0.01-5.0% and Zr: 0.01-5.0%, and Ag: 0.1-5.0% in mass%, and also the following 1st The total amount of one or more components selected from at least one of the groups to the third group is 5.0% or less, and Bi, Tl, Rb, Cs, Sr, Ba, Tc, Re, Os, Rh, Including one or more selected from In, Pd, Po, Sb, Hf, Au, and Ga in a total amount of 0.001 to 0.3%, with the balance being Cu and impurities, the precipitates and inclusions present in the alloy Among them, a Cu alloy having a particle size of 10 μm or more per unit area is a total of 100 pieces / mm ² or less.
Group 1: 0.001 to 0.5% P and B by mass%
Second group: 0.01% to 5.0% Sn, Mn, Fe, Co, Al, Si, Nb, Ta, Mo, V, W and Ge, respectively, by mass%
Third group: 0.01% to 3.0% by mass of Zn, Ni, Te and Se, respectively Contains 2 or more selected from Cr: 0.01-4.0%, Ti: 0.01-5.0% and Zr: 0.01-5.0% by mass%, selected from Mg, Li, Ca and rare earth elements In addition, 0.001 to 2.0% in total is included, and Bi, Tl, Rb, Cs, Sr, Ba, Tc, Re, Os, Rh, In, Pd, Po, Sb, Hf, Au, and Ga The total amount of one or more selected elements is 0.001 to 0.3%, the balance is Cu and impurities, and the total number of precipitates and inclusions in the alloy with a particle size of 10 μm or more per unit area Cu alloy characterized by being 100 pieces / mm ² or less. 2% or more selected from Cr: 0.01-4.0%, Ti: 0.01-5.0% and Zr: 0.01-5.0%, and Ag: 0.1-5.0% by mass%, Mg, Li, Ca And a total of 0.001 to 2.0% of one or more selected from rare earth elements, Bi, Tl, Rb, Cs, Sr, Ba, Tc, Re, Os, Rh, In, Pd, Po, Sb, One or more selected from Hf, Au and Ga is contained in a total amount of 0.001 to 0.3%, the balance is made of Cu and impurities, and the precipitates and inclusions present in the alloy have a particle size of 10 μm or more. A Cu alloy characterized in that the total number per unit area is 100 / mm ² or less. 2% or more selected from Cr: 0.01-4.0%, Ti: 0.01-5.0% and Zr: 0.01-5.0% by mass%, and at least of the following 1st group to 3rd group One or more components selected from one group are included in a total amount of 5.0% or less, and one or more components selected from Mg, Li, Ca and rare earth elements are included in total of 0.001 to 2.0%, and Bi, Tl , Rb, Cs, Sr, Ba, Tc, Re, Os, Rh, In, Pd, Po, Sb, Hf, Au, and Ga in a total amount of 0.001 to 0.3%, the balance being A Cu alloy comprising Cu and impurities, wherein the total number of precipitates and inclusions present in the alloy having a particle size of 10 μm or more per unit area is 100 pieces / mm ² or less.
Group 1: 0.001 to 0.5% P and B by mass%
Second group: 0.01% to 5.0% Sn, Mn, Fe, Co, Al, Si, Nb, Ta, Mo, V, W and Ge, respectively, by mass%
Third group: 0.01% to 3.0% by mass of Zn, Ni, Te and Se, respectively 2% or more selected from Cr: 0.01-4.0%, Ti: 0.01-5.0% and Zr: 0.01-5.0%, and Ag: 0.1-5.0% by mass%, the following 1st group To a third group containing at least one component selected from at least one group in a total amount of 5.0% or less, and a total of one or more components selected from Mg, Li, Ca and rare earth elements from 0.001 to In addition, it contains 2.0%, and more than one selected from Bi, Tl, Rb, Cs, Sr, Ba, Tc, Re, Os, Rh, In, Pd, Po, Sb, Hf, Au and Ga in total amount 0.001 to 0.3% inclusive, the balance consisting of Cu and impurities, the total number of precipitates and inclusions in the alloy with a particle size of 10 μm or more per unit area is 100 pieces / mm ² or less Cu alloy characterized by
Group 1: 0.001 to 0.5% P and B by mass%
Second group: 0.01% to 5.0% Sn, Mn, Fe, Co, Al, Si, Nb, Ta, Mo, V, W and Ge, respectively, by mass%
Third group: 0.01% to 3.0% by mass of Zn, Ni, Te and Se, respectively   The Cu alloy according to any one of claims 1 to 16, wherein a crystal grain size is 0.01 to 35 µm. A slab obtained by melting and casting the Cu alloy having the chemical composition according to any one of claims 1 to 16, at least in a temperature range from a slab temperature immediately after casting to 450 ° C, at 0.5 ° C / Cu having a particle size of 10 μm or more among the precipitates and inclusions present in the alloy, the total number of which per unit area is 100 / mm ² or less, characterized by cooling at a cooling rate of s or more Alloy manufacturing method. A slab obtained by melting and casting the Cu alloy having the chemical composition according to any one of claims 1 to 16, at least in a temperature range from a slab temperature immediately after casting to 450 ° C, at 0.5 ° C / Cooling at a cooling rate of s or more and processing in a temperature range of 450 ° C. or less, the total number of precipitates and inclusions present in the alloy per unit area having a particle size of 10 μm or more The manufacturing method of Cu alloy which is 100 pieces / mm < ² > or less. A slab obtained by melting and casting the Cu alloy having the chemical composition according to any one of claims 1 to 16, at least in a temperature range from a slab temperature immediately after casting to 450 ° C, at 0.5 ° C / Precipitation existing in the alloy, characterized in that it is cooled at a cooling rate of s or more, processed in a temperature range of 450 ° C. or less, and then subjected to a heat treatment held in a temperature range of 280 to 550 ° C. for 10 minutes to 72 hours. A Cu alloy manufacturing method in which the number per unit area of the inclusions and inclusions having a particle diameter of 10 μm or more is 100 pieces / mm ² or less in total.   21. The method for producing a Cu alloy according to claim 20, wherein the processing in a temperature range of 450 [deg.] C. or less and the heat treatment for 10 minutes to 72 hours in the temperature range of 280 to 550 [deg.] C. are performed a plurality of times. The method for producing a Cu alloy according to claim 20 or 21, wherein processing is performed in a temperature range of 450 ° C or lower after the last heat treatment.

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