WO2006109801A1

WO2006109801A1 - Copper alloy and process for producing the same

Info

Publication number: WO2006109801A1
Application number: PCT/JP2006/307658
Authority: WO
Inventors: Tsuneaki Nagamichi; Yasuhiro Maehara; Naotsugu Yoshida; Mitsuharu Yonemura; Keiji Nakajima; Takuji NAKAHATA
Original assignee: Sumitomo Metal Industries, Ltd.
Priority date: 2005-04-12
Filing date: 2006-04-11
Publication date: 2006-10-19
Also published as: TW200643191A

Abstract

[PROBLEMS] To provide a beryllium-free copper alloy satisfactory in various performances. [MEANS FOR SOLVING PROBLEMS] The copper alloy has a given chemical composition, the remainder consisting of copper and impurities. In the copper alloy, the crystal structure has an aspect ratio of 5 or lower and the total number of precipitates and inclusions having a particle diameter of 1 µm or larger satisfies the following relationship (1). This copper alloy is obtained by melting, casting, subsequently cooling the cast at a rate of 1 °C/sec or higher at least in the temperature range of from the temperature of the cast immediately after the casting to 900°C, and subjecting the cast to a solution heat treatment and/or hot rolling. logN≤0.4742+17.629×exp(-0.1133×X) (1) In the relationship (1), N is the total number of the precipitates and inclusions per unit area (mm2) and X is the particle diameter of the precipitates and inclusions (µm).

Description

Copper alloy and manufacturing method thereof

Technical field

[0001] The present invention relates to a copper alloy and a method for producing the same without using an element that adversely affects the environment such as Be. Applications of this copper alloy include electrical and electronic parts and safety tools.

[0002] Examples of electrical and electronic parts include the following. In the electronics field, PC connectors, semiconductor sockets, optical pickups, coaxial connectors, and IC checker pins are listed. In the field of communications, mobile phone parts (connectors, knottery terminals, antenna parts), submarine repeater housings, exchange connectors, etc. are listed. In the automotive field, there are various electrical components such as relays, various switches, micromotors, diaphragms, and various terminals. In the aerospace field, landing gears for aircraft are listed. Medical / analytical instruments include medical connectors and industrial connectors. In the field of home appliances, relays for home appliances such as air conditioners, optical pickups for game machines, card media connectors, etc.

[0003] Safety tools include, for example, drilling rods, spanners, chain blocks, hammers, drivers, pliers, and -padpers used in places where there is a risk of explosion from sparks, such as ammunition stores and coal mines. There are tools.

Background art

[0004] Conventionally, as a copper alloy used in the above-described electrical and electronic parts, a Cu-Be alloy aimed at strengthening by aging precipitation of Be is known. This alloy is widely used as a spring material because of its excellent tensile strength and electrical conductivity. However, Be oxides are formed in the Cu-Be alloy manufacturing process and the process of casting this alloy to various parts.

[0005] Be is a substance harmful to the environment. For this reason, in the manufacture and processing of copper alloys, it is necessary to provide a treatment process for Be oxide, which increases the manufacturing cost and becomes a problem in the recycling process of electrical and electronic parts. Therefore, the emergence of a material that does not use Be and has both excellent tensile strength and conductivity is expected. [0006] Patent Document 1 proposes a copper alloy in which Ni Si is deposited, which is called a Corson series.

2

. 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. It's a thing.

[0007] However, this alloy has limitations in both strength enhancement and high electrical conductivity, and there remains a problem in terms of product noirishment as described below. This alloy is Ni Si

2 It has age-hardening properties. And when Ni and Si contents are reduced to increase the conductivity, the tensile strength decreases significantly. On the other hand, in order to increase the amount of Ni Si precipitation, Ni and

2

Even if the amount of Si is increased, there is a limit to the increase in tensile strength, and the conductivity is significantly reduced. For this reason, the Corson alloy has a poor balance between the tensile strength and the conductivity in the region where the tensile strength is high and the region where the electrical conductivity is high, resulting in a narrow product norelation. This is due to the following reasons.

[0008] The electrical resistance of the alloy (or its reciprocal conductivity) 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 (remarkably decreases the electrical conductivity), so in the above-mentioned Corson alloy, the electrical conductivity decreases when the Ni content is increased. On the other hand, the tensile strength of the copper 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 Si, there is a limit to increasing the strength in terms of both precipitation and dispersion.

2

The

[0009] Patent Document 2 discloses a copper alloy having a good wire-bonding property, which includes elements such as Cr and Zr, and defines surface hardness and surface roughness. As described in the examples, this copper alloy is manufactured on the premise of hot rolling and solution treatment.

[0010] However, in order to perform hot rolling, it is necessary to clean the surface in order to prevent hot cracking and to remove scale, resulting in a decrease in yield. In addition, since it is often heated in the atmosphere, active additive elements such as Si, Mg, and Al are likely to oxidize. For this reason, there are many problems such as the generated coarse internal oxides causing the deterioration of the characteristics of the final product. Furthermore, enormous energy is required for hot rolling and solution treatment. Thus, in the copper alloy described in Cited Document 2, Since it is premised on processing and solution treatment, there are problems in terms of viewpoints such as reduction of manufacturing costs and energy savings, as well as product characteristics (such as tensile strength and electrical conductivity in addition to tensile strength and conductivity) resulting from the formation of coarse oxides. , Bending workability, fatigue characteristics, etc.) are deteriorated.

[0011] On the other hand, the material for the safety tool is required to have mechanical properties comparable to tool steel, for example, high strength and wear resistance, and no sparks that cause an explosion are generated. It is required to be excellent in generation. For this reason, copper alloys with high thermal conductivity, especially Cu-Be alloys aimed at strengthening by aging precipitation of Be, have been frequently used as safety tool materials. As mentioned above, Cu-Be alloy is a material with many environmental problems. Nevertheless, Cu-Be alloy has been widely used as a safety tool material for the following reasons.

FIG. 1 is a graph showing the relationship between the electrical conductivity [IACS (%)] and the thermal conductivity [TC (WZm′K)] of a copper alloy. As shown in Fig. 1, the two are in a 1: 1 relationship, and increasing the conductivity [IACS (%;)] increases the thermal conductivity [TC (W / mK)]. In other words, it is nothing other than increasing the spark resistance. When a sudden force is applied when using a tool, a spark is generated because a specific component in the alloy is burned by the heat generated by the impact. As described in Non-Patent Document 1, since the thermal conductivity of steel is as low as 1Z5 or less than that of copper, local temperature rise is likely to occur. Steel contains C, so “c + o →

2

It causes the reaction of “CO” to generate sparks. In fact, in pure iron that does not contain C

2

It is known that no sparks occur. Other metals that are prone to sparks are cocoons or Ti alloys. This is because the thermal conductivity of Ti is extremely low with 1Z20, which is copper, and the reaction of “Ti + 0 → TiO” occurs. Note that FIG. 1 shows the data shown in Non-Patent Document 1.

twenty two

Data.

[0013] However, as described above, the conductivity [IACS (%;)] and the 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 copper alloy other than the Cu-Be alloy described above, which had a sufficiently high thermal conductivity TC while having a high tensile strength comparable to that of tool steel.

[0014] Patent Document 1: Japanese Patent No. 2572042

Patent Document 2: Japanese Patent No. 2714561 Non-patent document 1: Industrial heating, Vol.36, No.3 (1999), published by Japan Industrial Furnace Association, page 59 Disclosure of invention

Problems to be solved by the invention

[0015] The first object of the present invention is a copper alloy that does not contain elements harmful to the environment such as Be, has abundant product nomination, is excellent in high-temperature strength, ductility, and bending workability. An object of the present invention is to provide a high-strength, high-workability copper alloy that is excellent in performance required for a material for safety tools, that is, thermal conductivity, wear resistance and spark resistance. The second object of the present invention is to provide a method for producing a copper alloy having the same components as described above, but having superior ductility and bending caloricity as compared with conventional production methods.

[0016] “Product richness is abundant” means that the amount of conductivity and tensile strength is about the same as or higher than that of Be-added copper alloy by finely adjusting the additive amount and Z or manufacturing conditions. From the level, it has been known in the past! It means that you can adjust to the level.

[0017] Note that "the balance between conductivity and tensile strength is at the same level as or higher than that of the Be-added copper alloy" specifically means that the following equation (a) is satisfied. Means. 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 X exp (-0.0513 X IACS)---(a)

However, TS in equation (a) means tensile strength (MPa), and IACS means conductivity (%).

[0018] The copper alloy is required to have a certain degree of high-temperature strength in addition to the above-described tensile strength and conductivity characteristics. This is also the force that, for example, connector materials used in automobiles and computers can be exposed to environments above 200 ° C. When pure Cu is heated to 200 ° C or higher, the room temperature strength decreases significantly and the desired spring characteristics can no longer be maintained. However, the above Cu-Be alloys and Corson alloys are heated to 400 ° C. Even after this, the room temperature strength hardly decreases.

[0019] Therefore, for applications that require high-temperature strength, it is desirable that the level be equal to or higher than that of Cu-Be alloys. Specifically, the heating temperature at which the rate of decrease in hardness before and after the heating test is 50% is defined as the heat resistance temperature, and when the heat resistance temperature exceeds 350 ° C or higher The strength is excellent. More preferably, the heat resistant temperature is 400 ° C or higher.

[0020] The target of bending cacheability is to be equal to or higher than that of Cu-Be alloys. Specifically, the test piece was subjected to a 90 ° bending test with various radii of curvature, and the minimum radius of curvature R without cracking was measured, and the ratio B (= RZt) of this to the thickness t Bending workability can be evaluated. In general, bending deformation in the 0-degree direction is relatively easy (good way), and bending deformation in the 90-degree direction is relatively difficult (bad way). By comparing, the anisotropy of characteristics was evaluated. The good range of bending workability is when B≤3.0 in the 0 degree direction and B≤6.0 in the 90 degree direction. Since R varies depending on the plate thickness, in the present invention, the bending calorability was evaluated based on the test at 0.20 mm thickness.

[0021] In addition to the above-described properties of tensile strength TS and conductivity IACS, copper alloys as safety tools are required to have wear resistance. Therefore, in the case of copper alloy for safety tools, the target is to have the same level of wear resistance as tool steel. Specifically, the wear resistance is excellent when the hardness at room temperature is 250 or more in terms of Vickers hardness.

Means for solving the problem

[0022] The gist of the present invention is a method for producing the copper alloys shown in the following (A) to (C) and the copper alloy shown in the following (D).

[0023] (A) Zn, Sn, Ag, Mn, Fe, Co, Al, Ni, Si, Mo, V, Nb, Ta, W, Ge, Te and Se Selected 1 or 2 types The total amount is 0.1 to 20% by mass, the remainder is made of copper and impurities, the aspect ratio of the crystal grains of the copper-based matrix is 5 or less, and the precipitates and inclusions present in the alloy A copper alloy with a grain size of 1 μm or more and the total number of precipitates and inclusions satisfying the relationship expressed by the following formula (1) logN≤ 0.4742 + 17.629 X exp (-0.1133 XX)

However, N means the total number of precipitates and inclusions per unit area (pieces Zmm ² ), and X means the grain size (μm) of the precipitates and inclusions.

[0024] (B) at a mass ^{_{0/0, Ti: 0.01~5%}} , Zr: 0.01~5% and Hf: contains 0.01 to 5% of the Churyoku et chosenヽdeviated force one, further, Zn, Sn, Ag, Mn, Fe, Co, Al, Ni ゝ Si ゝ Mo, V, Nb, Ta , W, Ge, Te and Se medium strength 0.01% to 20% in total of one or more selected, with the balance consisting of copper and impurities, and the crystal aspect ratio of the copper matrix is 5 In addition to the following, the particle size of the precipitates and inclusions present in the alloy having a particle size of 1 μm or more and the total number of precipitates and inclusions are expressed by the above equation (1). Copper alloy characterized by satisfying

[0025] In (C) Weight ^_0/0, Cr: contains 0.01 to 5%, more, Zn, Sn, Ag, Mn , Fe, Co, Al, Ni, Si, Mo, V, Nb, Ta, The medium strength of W, Ge, Te, and Se is also selected, including 0.01 to 20% in total of one or more selected, with the balance consisting of copper and impurities, and the aspect ratio of the crystal grains of the copper-based matrix And the total number of precipitates and inclusions and the total number of precipitates and inclusions is represented by the above formula (1). A copper alloy characterized by satisfying the relationship.

[0026] The copper alloys (A) to (C) described above are replaced with a part of copper, and a total of 0.001 to 2% by mass of Mg, Li, Ca and rare earth elements are also selected. two or more, or Z and, in total 0.0001 mass ^_0/0 of P, B, Bi, Tl, Rb, Cs, Sr, Ba, Tc, Re, Os, Rh, in, Pd, Po, Sb , Au, Ga, S, Cd, As and Pb may contain one or more selected ones. The crystal grain size of these copper alloys is preferably 0.01 to 35 m.

[0027] (D) A piece obtained by melting and producing a copper alloy having the chemical composition described in any one of (A) to (C) above, and producing at least a piece immediately after forging. The aspect ratio of the crystal grains of the copper-based matrix phase is characterized by performing solution treatment and Z or hot rolling after cooling at a cooling rate of l ° CZs or higher in the temperature range from temperature to 900 ° C. Copper having a particle size of 1 μm or more among the precipitates and inclusions present in the alloy and the total number of precipitates and inclusions satisfying the following formula (1): Alloy manufacturing method.

logN≤ 0.4742 + 17.629 X exp (— 0.1133 X X) · · · (1)

[0028] After the solution treatment and Z or hot rolling, it is desirable to perform heating in a temperature range of 600 ° C or lower, or further, heat treatment for holding in a temperature range of 150 to 750 ° C. Solution treatment and Z or hot rolling, processing at temperatures below 600 ° C, and 150-750 The heat treatment held in the temperature range of ° C may be performed a plurality of times. In addition, solution treatment and Z or hot rolling, processing in a temperature range of 600 ° C or less, and heat treatment holding in a temperature range of 150 to 750 ° C need not be performed in this order. In addition, processing in a temperature range of 600 ° C or lower and heat treatment in a temperature range of 150 to 750 ° C may be performed. After the last step, you may carry out processing in the temperature range below 600 ° C! /.

In the present invention, the precipitate is a metal or a compound of copper and an additive element, or a compound of additive elements, for example, Cu Ti for a Ti additive, Cu Zr for a Zr additive, Ma

4 9 2 In the case of Cr additive, metallic Cr precipitates. Further, the inclusion is a metal oxide, a metal carbide, a metal nitride or the like.

BEST MODE FOR CARRYING OUT THE INVENTION

[0030] Hereinafter, embodiments of the present invention will be described. In the following description, “%” means “mass%” depending on the content of each element.

[0031] 1. About the copper alloy of the present invention

(A) Chemical composition

The copper alloy of the present invention contains Zn, Sn, Ag, Mn, Fe, Co, Al, Ni, Si, Mo, V, Nb, Ta, W, Ge, Te and Se (hereinafter, these elements are referred to as “first Medium strength (referred to as “group element”) 0.1 to 20% of each one selected, or a total of 0.1 to 20% of two or more, with the balance being a chemical composition consisting of copper and impurities.

[0032] These elements are elements having an effect of improving corrosion resistance and heat resistance while maintaining a balance between strength and electrical conductivity. This effect is exhibited when these elements contain a total of 0.1% or more. However, when these contents are excessive, the conductivity decreases. Therefore, when these elements are contained, the total content of one or more kinds needs to be in the range of 0.1 to 20%. Ag and Sn, in particular, contribute to high strength through fine precipitation, and are therefore preferably used positively. When the following second element is included, the strength can be secured by the second element, so the lower limit of the first element can be lowered to 0.01%.

[0033] In the alloy of the present invention, instead of a part of copper, Ti: 0.01-5%, Zr: 0.01-5%: fet ^ Hf: 0.0 1-5% It may contain seeds Cr: Even if it contains 0.01 to 5% Good. Hereinafter, these elements are referred to as “second group elements”.

[0034] Ti: 0.01-5%, Zr: 0.01-5% and Hf: 0.01-5%

Since Ti, Zr, or Hf are all effective elements for improving the tensile strength, any one of these elements may be contained in the copper alloy of the present invention. The effect of improving the strength becomes significant when the content of these elements is 0.01% or more. However, if its content exceeds 5%, the strength increases, but the conductivity, workability, and bendability deteriorate. Therefore, the content of any one of Ti, Zr and Hf is preferably 0.01 to 5%. In order to obtain a state where the balance between tensile strength and electrical conductivity is extremely good, it is more desirable to contain these elements in an amount of 0.1% or more.

[0035] Cr: 0.01 to 5%

Cr is an element effective for improving the tensile strength without increasing the electrical resistance. In order to obtain the effect, it is desirable to contain 0.01% or more. In particular, in order to obtain a state in which the balance of tensile strength and electrical conductivity is about the same as or higher than that of the Cu—Be alloy, it is desirable to contain 0.1% or more. On the other hand, if the Cr content exceeds 5%, metal Cr precipitates coarsely and adversely affects ductility, bending workability, fatigue properties, and the like. Therefore, when Cr is contained, its content is preferably 0.01 to 5%.

[0036] For the purpose of increasing the high temperature strength, the copper alloy of the present invention, instead of a part of copper, 0.001 to 2% of one selected from among Mg, Li, Ca and rare earth elements, respectively, or It is desirable to include two or more kinds in a total of 0.001 to 2%. These are hereinafter referred to as “Group 3 elements”.

[0037] Mg, Li, Ca and rare earth elements are elements that increase the high-temperature strength by combining with oxygen atoms in the copper matrix to form fine oxides. The effect becomes significant when the total content of these elements is 0.001% or more. However, if its content exceeds 2%, the above effects are saturated, and the force also has problems such as a decrease in electrical conductivity and a deterioration in ductility and bending workability. Therefore, the total content when Mg, Li, Ca and one or more selected rare earth elements are included is preferably 0.001 to 2%. In addition, rare earth elements mean Sc, Y and lanthanoids, and each element may be added alone, or misch metal may be added.

[0038] The copper alloy of the present invention is intended to increase the width (ΔΤ) of the liquidus and solidus at the time of alloy penetration. Therefore, P, B, Bi ゝ Tl, Rb, Cs, Sr, Ba, Tc, Re, Os, Rh, In, Pd, Po, Sb, Au, Ga, S, Cd It is desirable to include 0.0001 to 3% of the selected one of As and Pb, or 0.0001 to 3% in total of 2 or more. As, Pd and Cd are harmful elements and should not be used as much as possible. These are hereinafter referred to as “Group 4 elements”. Note that Δ 力 is a force that increases due to the so-called supercooling phenomenon in the case of rapid solidification. Here, we consider ΔT in a thermal equilibrium state as a guide.

[0039] All of these elements have the effect of lowering the solidus and expanding ΔΤ. If this ΔΤ is large, a certain period of time can be secured from solidification until solidification, so it becomes easy to pour, but if ΔΤ is too wide, the yield strength in the low temperature range decreases and cracking occurs at the end of solidification. So-called solder brittleness occurs. Therefore, ΔΤ is preferably in the range of 50 to 200 ° C.

[0040] 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, they have the effect of strengthening the alloy, particularly the high-temperature strength, in the same manner as the precipitates of the compounds of metals or copper and additive elements described later, or compounds of additive elements. Therefore, you may add actively. For example, O has the effect of increasing the high temperature strength by forming an acid oxide. This effect is easily obtained in alloys containing elements that easily form oxides such as Mg, Li, Ca and rare earth elements, Al, and Si. In this case, however, it is necessary to select conditions so that no solid solution O remains. Residual solute oxygen causes H 2 O gas during heat treatment in a hydrogen atmosphere, causing a steam explosion, causing a so-called hydrogen disease, blistering, etc.

2

May generate and deteriorate the quality of the product, so be careful.

[0041] When each of these elements exceeds 1%, coarse precipitates or inclusions are formed, and ductility and bending workability are reduced. Therefore, it is preferable to limit each to 1% or less. More preferred is 0.1% or less. If H is contained as an impurity in the alloy, H

2 Since the gas remains in the alloy and causes rolling defects, the content is preferably as low as possible.

[0042] Note that Be is another impurity element. Be may be mixed in a copper alloy when scrap is used in large quantities as a raw material. This content should be as low as possible However, it is acceptable if it is less than 0.1%.

[0043] (B) Total number of precipitates and inclusions

In the copper alloy of the present invention, among the precipitates and inclusions present in the alloy, the particle size of particles having a particle size force of m or more and the total number of precipitates and inclusions satisfy the following formula (1). is required.

logN≤ 0.4742 + 17.629 X exp (— 0.1133 X X) · · · (1)

Here, N means the total number of precipitates and inclusions per unit area (pieces Zmm ² ), and X means the grain size m of the precipitates and inclusions. In Equation (1), when the measured force of the particle size of precipitates and inclusions is 1.0 μm or more and less than 1.5 μm, substitute X = 1, and (a−0.5) μ m or more (a + 0.5) If it is less than μm, substitute Χ = α (α is an integer of 2 or more).

[0044] In the copper alloy of the present invention, the strength is improved without lowering the conductivity by finely depositing a precipitate of a metal or a compound of copper and an additive element, or a compound of the same additive element. Can be made. These increase the strength by precipitation hardening. Solid solution of Cr, Ti, and Zr decreases by precipitation, and the conductivity of the copper matrix approaches that of pure copper

[0045] However, if these precipitates and inclusions such as metal oxides, metal carbides, metal nitrides, etc. are coarsely deposited with a particle size of 20 m or more, the ductility is reduced and, for example, when processing into a connector. Cracking and chipping are likely to occur during bending and punching. In addition, fatigue characteristics may adversely affect impact resistance 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 excessively in the aging treatment process, fine precipitation of these precipitates and the like is hindered, and the strength of the copper alloy cannot be increased. Such a problem is caused by the relationship represented by the above equation (1) with the particle size of the precipitates and inclusions present in the alloy having a particle size of 1 μm or more, the total number of precipitates and inclusions. It becomes remarkable when not satisfying.

[0046] Therefore, in the present invention, among the precipitates and inclusions present in the alloy, the particle size of those having a particle size of Lm or more, the total number of precipitates and inclusions, and the above formula (1) Satisfaction is defined as an essential requirement. The desirable total number of precipitates and inclusions is when the following equation (2) is satisfied, and more desirably when the following equation (3) is satisfied. In addition, these The particle size of each and the total number of precipitates and inclusions can be determined by the method shown in the examples.

logN≤ 0.4742 + 7.9749 X exp (— 0.1133 X X) · · · (2)

logN≤ 0.4742 + 6.3579 X exp (-0.1133 XX)

[0047] (C) Aspect ratio of crystal yarn and weave

If the aspect ratio of the copper-based matrix exceeds 5, it is impossible to obtain substantially isotropic characteristics as a copper-based matrix. In such a structure, the mechanical properties (strength, ductility, bending workability, etc.) are, for example, in the rolling direction (direction parallel to the rolling direction: here defined as the 0 degree direction) and in the direction perpendicular to the rolling (perpendicular to the rolling direction). The width direction (defined here as the 90-degree direction) is different, that is, the anisotropy of the characteristics increases, which causes problems such as restrictions on the molding direction and sampling direction. Also, the bending workability itself deteriorates. Therefore, the crystal structure aspect ratio was set to 5 or less. Smaller aspect ratio is better 4 or less is preferred. If it is 3 or less, it is more preferable. If the aspect ratio is close to 1, the value is even better.

[0048] The aspect ratio defined in the present invention is the average value of the (maximum diameter) / (minimum diameter) values of the crystal grains of the copper-based matrix, regardless of the direction of the structure observation. . The “maximum diameter” of a crystal grain is the longest diameter of the crystal grain, and the “minimum diameter” of the crystal grain is the shortest of the crystal grain! For example, several fields of tissue were photographed with an optical microscope or scanning electron microscope (SEM), and the `` maximum diameter '' and `` minimum diameter '' obtained by the linear cutting method using this tissue photograph were calculated as 1. 1 3 The doubled ones should be the “maximum diameter” of the crystal grains and the “minimum diameter” of the crystal grains!

[0049] (D) About crystal grain size

If the crystal grain size of the copper 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 m, the high-temperature strength tends to decrease, and when it exceeds 35 m, the ductility decreases. Accordingly, the crystal grain size is desirably 0.01 to 35 m. A more desirable particle size is 0.05 to 30 / ζ πι. Most preferred is 0.1 to 25 πι.

[0050] The average crystal grain size of the copper matrix is, for example, an optical microscope or a scanning electron microscope (S This is a value obtained by multiplying the average section length measured by the linear cutting method using this tissue photograph by a number of fields by 1.13.

[0051] 2. Method for producing copper alloy of the present invention

In the copper alloy of the present invention, inclusions such as metal oxides, metal carbides, and metal nitrides that prevent fine precipitation of a metal or a compound of copper and an additive element, or a compound of additive elements, are solidified in a piece. Easy to generate immediately after. In order to suppress the formation of these inclusions, it is most important to adjust the cooling rate after solidification. As will be described later, solution treatment and Z or hot rolling are necessary to reduce the aspect ratio of the crystal grains of the copper base matrix to 5 or less in order to ensure isotropic properties. There is. However, as a result of research by the present inventors, it is clear that the formation and coarsening of the inclusions can be suppressed even if such a hot process is performed if the temperature of the flake is cooled to some extent. became

[0052] Therefore, in the method for producing a copper alloy according to the present invention, a copper alloy having the above chemical composition is melted, and the piece obtained by forging is at least from the piece temperature immediately after forging. In a temperature range up to 900 ° C, after cooling at a cooling rate of 1 ° CZs or higher, solution treatment and Z or hot rolling are performed, so that the aspect ratio of the crystal grains of the copper base matrix is 5 or less. However, among the precipitates and inclusions present in the alloy, the particle size of the particles having a particle size of Lm or more and the total number of precipitates and inclusions satisfy the following formula (1): did.

logN≤ 0.4742 + 17.629 X exp (-0.1133 X X)

[0053] After the above-mentioned solution treatment and Z or hot rolling, it is subjected to calorie in a temperature range of 600 ° C or lower, or heat treatment held in a temperature range of 150 to 750 ° C after this processing. I want it! It is more desirable to perform the processing in the temperature range of 600 ° C or less and the heat treatment held in the temperature range of 150 to 750 ° C multiple times. You may perform said process after the last heat processing.

[0054] (A) Cooling rate at least in the temperature range from the piece temperature immediately after fabrication to 900 ° C: 1 ° CZs or more Precipitates such as a compound of metal or copper and an additive element, or a compound of additive elements are formed in a temperature range of 280 ° C or higher. In particular, when the cooling rate in the temperature range from the piece temperature immediately after fabrication to 900 ° C is slow, inclusions such as metal oxides, metal carbides, and metal nitrides are coarsely formed, and the particle size is 20 m. In addition, it may reach several hundreds / zm. In addition, the above precipitates also become coarser than 20 m. In the state where such coarse precipitates and inclusions are formed, the precipitation hardening action of the precipitates in the aging process, which is not only likely to cause cracks and breaks during subsequent processing, is impaired. High strength cannot be achieved.

[0055] Therefore, at least in this temperature range, it is necessary to cool the piece at a cooling rate of 1 ° CZs or more. The higher the cooling rate, the more preferable the cooling rate is 2 ° CZs or more, and the more preferable is 5 ° CZs or more. If the strip is cooled at such a cooling rate, precipitates and inclusions will not be coarsened even if a solution solution treatment and Z or hot rolling are subsequently performed. In addition, there is no particular limitation on the upper limit of the cooling rate. Force To reduce the cooling rate in this temperature range to more than 100 ° C / s, it is necessary to reduce the thickness of the copper alloy, resulting in increased productivity. Getting worse. From this point of view, the cooling rate in this temperature range is preferably 100 ° C / s or less, more preferably 90 ° C / s or less. More desirable is 80 ° C / s or less.

[0056] (B) Solution treatment and Z or hot rolling conditions

Solution treatment and Z or hot rolling are effective for isotropic, homogenizing, and fine graining of crystal structures. As a result, high strength and excellent workability of the final product can be obtained uniformly and stably, and both the strength and the anisotropy of the characteristics can be reduced. In particular, bending workability can be improved and bending workability anisotropy can be reduced.

[0057] The solution treatment and Z or hot rolling are preferably performed in a temperature range of 600 ° C or higher and 1060 ° C or lower. If it is less than 600 ° C, the crystal structure may not be isotropic, homogeneous or fine grained, and the aspect ratio of the crystal grain of the copper base matrix in the final product cannot be reduced to 5 or less. In some cases, good characteristics cannot be obtained uniformly and the anisotropy of characteristics increases. On the other hand, if the temperature of the solution treatment and Z or hot rolling exceeds 1060 ° C, the grain boundaries melt and cracks occur during processing, or the coarsening of the grains causes the final product. Characteristics There is a possibility that problems such as reduction and anisotropy of characteristics increase.

[0058] Accordingly, the solution treatment and Z or hot rolling are preferably performed in a temperature range of 600 ° C or higher and 1060 ° C or lower. Preferably they are 650 degreeC or more and 1000 degrees C or less, More preferably, they are 700 degreeC or more and 900 degrees C or less. In the temperature range of 900 to 1,060 ° C., coarse precipitation of the inclusions and coarsening of the crystal grains of the copper base matrix are remarkable.

[0059] When the solution treatment time or the heating time before hot rolling is less than 3.0 seconds, the desired crystal structure cannot be obtained even if the solution treatment temperature or the heating temperature before hot rolling is set high. Accordingly, it is desirable that the solution treatment in the temperature range of 600 to 160 ° C. or the heating before hot rolling be performed for 3.0 seconds or more. This time is preferably 1 minute or longer and more preferably 5 minutes or longer. More desirable is 10 minutes or more. Although the upper limit of these times is not particularly defined, coarse precipitation of inclusions such as metal or a compound of copper and an additive element, a compound of additive elements, or a metal oxide, metal carbide, or metal nitride It is desirable to suppress it, suppress coarsening of crystal grains, and reduce the heating cost for 24 hours or less. When the solution treatment temperature and the heating temperature before hot rolling are high, the heating time can be shortened. It is desirable to hold for a short time in the temperature range of 900 to 160 ° C on the high temperature side.

[0060] The rolling reduction in hot rolling is not particularly defined, but is preferably 20% or more as the total rolling reduction from the viewpoints of isotropic, homogenizing, and refinement of the crystal structure. More preferred is 50% or more.

[0061] Solution treatment and cooling after Z or hot rolling are preferably performed at a cooling rate of 1 ° C Zs or more in order to suppress precipitation of the inclusions and precipitates. The larger the cooling rate, the more preferable the cooling rate is 2 ° CZs or more, and the more preferable is 5 ° CZs or more.

[0062] Solution treatment and heating prior to Z or hot rolling are 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 mating properties are also ensured by the treatment under such an atmosphere.

[0063] Solution treatment and Z or hot rolling may be performed after "processing in a temperature range of 600 ° C or lower" or "aging treatment holding in a temperature range of 150 to 750 ° C" described later. . In this case, in order to precipitate the above inclusions and precipitates finely, the solution solution treatment and Z or hot After rolling, it is desirable to further perform “processing in a temperature range of 600 ° C. or lower” or “aging treatment maintained in a temperature range of 150 to 750 ° C.”.

[0064] (C) Processing temperature after solution treatment and Z or hot rolling: temperature range of 600 ° C or lower In the method for producing a copper alloy of the present invention, After cooling under conditions, the final product is obtained by a combination of the above solution treatment and Z or hot rolling, processing and aging heat treatment.

[0065] Processing such as rolling and drawing may be performed at 600 ° C or lower. For example, when adopting continuous fabrication, these processes may be performed in the cooling process after solidification. If processing is performed in a temperature range exceeding 600 ° C, strain during processing cannot be accumulated sufficiently, so that precipitation of a compound of a metal or copper and an additive element, or a compound of additive elements, etc. is performed during subsequent aging treatment. The product cannot be finely precipitated, and the strength of the copper alloy becomes insufficient.

[0066] The lower the processing temperature, the higher the dislocation density at the time of processing, so finer precipitates such as a compound of a metal or copper and an additive element, or a compound of additive elements can be obtained in a subsequent aging treatment. It can be deposited. For this reason, higher strength can be imparted to the copper alloy. Accordingly, the preferred cache temperature is 600 ° C. or lower, and more preferably 450 ° C. or lower. Most preferred is 300 ° C or lower. It may be 25 ° C or less.

[0067] It should be noted 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, leading to refinement of the precipitates and shortening the time required for precipitation, thereby improving conductivity. Reduction of harmful solid solution elements can be realized early.

[0068] (D) Aging treatment condition: Maintain in a temperature range of 150 to 750 ° C

The aging treatment is performed by depositing a metal or a compound of copper and an additive element, or a precipitate such as a compound of the additive elements to increase the strength of the copper alloy and, at the same time, a solid solution element (Cr, It is effective to improve conductivity by reducing Ti and the like. However, if the treatment temperature is less than 150 ° C, it takes a long time for the diffusion of the precipitated elements, which reduces productivity. On the other hand, if the treatment temperature exceeds 750 ° C, the precipitates become too coarse and not only can not be strengthened by precipitation hardening, but also have low ductility, bending workability, impact resistance and fatigue properties. I will give you. For this reason, it is desirable to perform the aging treatment in a temperature range of 150 to 750 ° C. Desirable aging temperature is 200-650 ° C, more preferably 250-550 ° C.

[0069] When the aging treatment time is less than 30 seconds, the desired precipitation amount cannot be secured even if the aging treatment temperature is set high. Therefore, it is desirable to perform an aging treatment in the temperature range of 150 to 750 ° C for 30 seconds or more. This treatment time is preferably 5 minutes or more, and more preferably 10 minutes or more. Most desirable is 15 minutes or more. There is no upper limit on the processing time, but it is desirable that it be 72 hours or less from the viewpoint of processing costs. When the aging treatment temperature is high, the treatment time can be shortened.

[0070] It should be noted that the aging treatment is preferably performed in a reducing atmosphere, an inert gas atmosphere, or a vacuum of 20 Pa or less in order to prevent the generation of scale due to surface oxidation. Excellent mating properties are also ensured by processing in such an atmosphere.

[0071] There is no limitation on the order in which the solution treatment, hot rolling, processing, and aging treatment are performed. For example, the processing may be performed after the solution treatment, or the solution treatment may be performed after the processing. Also good. Moreover, you may repeat these as needed. If it is repeated, the desired amount of precipitation can be obtained in a shorter time than with a single treatment (force and aging treatment), and a compound of metal or copper and an additive element, or a compound of additive elements. The precipitates such as can be deposited more finely.

[0072] (E) Other

In the method for producing a copper alloy of the present invention, conditions other than the above production conditions, for example, conditions such as melting and forging are not particularly limited, but may be carried out as follows, for example.

[0073] The dissolution is preferably performed in a non-acidic or reducing atmosphere. This is also a force that causes so-called hydrogen disease, in which water vapor is generated and blisters are generated in the subsequent process when the amount of dissolved oxygen in the molten copper increases. In addition, solid solution elements that easily oxidize, such as Ti, Cr, Zr, Mg, Li, Ca and rare earth elements, Al, Si, etc. If this remains in the final product, ductility, bending workability and fatigue properties are significantly reduced.

[0074] As a method for obtaining a piece, continuous forging is preferred in terms of productivity and solidification rate, but other methods such as an ingot method may be used as long as the method satisfies the above conditions. Also preferred The filling temperature is 1250 ° C or higher. More preferred is 1350 ° C or higher. At this temperature, Cr, Ti, Zr, etc. can be sufficiently dissolved, inclusions such as metal oxides, metal carbides, metal nitrides, etc., compounds of metal or copper and additive elements, or the same additive elements. This is because a precipitate such as a chemical compound is not generated.

[0075] In the case of obtaining pieces by continuous forging, 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 that does not easily react with the main alloying elements such as Ti, Cr, Zr, etc., for example, zirconia may be used.

Example 1

[0076] A copper alloy having the chemical composition shown in Table 1 was vacuum-melted in a high-frequency melting furnace, and was poured into a zirconia mold to a depth of 20 mm to obtain a flake. For rare earth elements, single elements or misch metals were added.

[0077] The obtained piece was cooled by spray cooling from 900 ° C, which was the temperature immediately after fabrication (the temperature immediately after removal from the mold). The temperature change of the vertical shape at a given location was measured by a thermocouple embedded in the vertical shape, and the surface temperature after the piece exited the vertical shape was measured with a contact thermometer. By using these results in combination with heat transfer analysis, the average cooling rate on the surface of the flakes up to 900 ° C was calculated. The solidification start point was obtained by thermal analysis during continuous cooling at a predetermined rate after preparing 0.2 g of molten metal for each component. A rolled material having a thickness of 15 mm, a width of 150 mm, and a length of 200 mm was produced from the obtained piece by cutting and cutting.

[0078] Thereafter, the inventive examples 1 to 9 and comparative examples 10 to 12 were subjected to the solution treatment and Z or hot rolling under the conditions shown in Table 2, and the comparative examples 13 to 20 were subjected to solution heat treatment and heat treatment. No hot rolling was performed. These rolled materials are rolled at a reduction rate of 73 to 94% at room temperature (first rolling) to form a 0.8 mm thick plate, and subjected to aging treatment (first aging) under specified conditions. Produced. Further, rolling at a reduction rate of 75% (second rolling) was performed at room temperature to a thickness of 0.2 mm, and an aging treatment (second aging) was performed under predetermined conditions.

[0079] With respect to the specimens thus prepared, the following methods were used to determine the particle diameter and total number of precipitates and inclusions per unit area, tensile strength, electrical conductivity, heat resistance temperature, and bending calorieability. . These results are shown in Table 3.

[0080] <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 liquid in which ammonia and hydrogen peroxide solution are mixed at a volume ratio of 9: 1, and then optical microscope is used. A 1 mm x 1 mm field of view was observed with a microscope at a magnification of 100 times. After that, the value obtained by measuring the major axis of the precipitates and inclusions (the length of the straight line in the grain that is the longest in the grain without touching the grain boundary in the middle) is defined as the grain size. In the formula (1), when the measured particle size of precipitates and inclusions is 1.0 / zm or more and less than 1.5 m, substitute X = l and (α− 0.5) m or more (α + 0.5) μ m If it is less than X, substitute X = a (a is an integer of 2 or more). Further, for each particle size, 1Z2 crosses the lmm X lmm field of view, and 1 within the frame, and calculates the total number n, and the number 任意 (= η + η + · · · + η) average value (ΝΖ

1 1 2 10

10) is defined as the total number of all precipitates and inclusions according to the particle size of each sample.

[0081] <Tensile strength and ductility>

In addition, a No. 13B tensile test piece specified in JIS Z 2201 was sampled from 0 ° and 90 ° with respect to the rolling direction, and subjected to a tensile test at room temperature (25 ° C) to obtain a tensile strength (TS). The fracture ductility (EL) was measured.

[0082] <Conductivity>

Take a test piece of width 10mm x length 60mm from the above specimen so that the longitudinal direction and the rolling direction are parallel, and pass a current in the longitudinal direction of the test piece to measure the potential difference at both ends 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 [from the ratio of the resistivity of 1.72 Ω 'cm of the standard sample annealed with polycrystalline pure copper [ IACS (%;)] was determined.

[0083] <Heat-resistant temperature>

A specimen having a width of 10 mm and a length of 10 mm is taken from the direction of 0 ° and 90 ° with respect to the rolling direction, and a cross section perpendicular to the rolling surface and parallel to the rolling direction is mirror-polished, A square pyramid diamond indenter was pushed into the test piece with a load of 50 g, and 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. [0084] Bending workability>

Samples with a width of 10 mm and a length of 60 mm were taken so that the longitudinal direction and the rolling direction were parallel to the direction at 0 ° and 90 ° with respect to the rolling direction, and the curvature radius of the bent part ( A 90 ° bend test was performed with different inner diameters. The bending part of the test piece after the test was observed from the outer diameter side using an optical microscope. Then, the ratio B (= RZt) with the thickness t of the test piece was determined using the minimum radius of curvature at which no cracks occurred.

[0085] [Table 1]

§§ [

Table 1 Chemical composition (mass, balance Gu and impurities)

* Means out of the chemical composition defined in the present invention.

S30083 Table 2

# Means that the chemical composition is outside the range defined in the present invention.

* Means that the manufacturing conditions are outside the range defined in the present invention.

¾ gall.

As shown in Table 23, in the present invention example 19, the chemical composition, production conditions, crystal structure of the copper base matrix, and the total number of precipitates and inclusions are within the range specified by the present invention. In addition to satisfying the formulas (1) to (3), high values were obtained for conductivity, strength, workability (ductility, bendability), and heat resistance temperature. Furthermore, the anisotropy of their characteristics is very small, and has excellent features! [0089] On the other hand, Comparative Examples 10 to 20 are defined by the present invention in terms of chemical composition, production conditions, the total number of precipitates and inclusions, the average crystal grain size of the copper base matrix, and the difference in aspect ratio. Since it was out of the range, the characteristics were inferior to those of the examples of the present invention, and their anisotropy was strong.

Example 2

[0090] A Cu alloy having the chemical composition shown in Table 4 was vacuum-melted in a high-frequency melting furnace and placed in a pig iron mold to obtain a piece having a thickness of 150 mm x width 170 mm x length 500 mm. Rare earth elements were added in the form of individual elements or misch metal. In some tests, the temperature history during cooling after pouring was measured with a thermocouple embedded in the bottom of the saddle, and the cooling curve at the center of the alloy lump was estimated in combination with heat transfer calculations. The average cooling rate up to 900 ° C after the start of solidification was 2 ± 0.3 ° C / s.

[0091] The hot metal portion of the obtained piece is cut off and hot forged to give a thickness of 50mm x width of 200mm

An alloy lump with an X length of 1200 mm was prepared. These were heated to 950 ° C and then hot rolled to a thickness of 10 mm. Note that the rolling end temperature was about 750 to 400 ° C., and cooling was performed in water after the end of rolling. Some were heat-treated by solution heat treatment and surface grinding to produce a rolled material with a thickness of 9 mm. These rolled materials were rolled at room temperature (first rolling) to form a plate with a thickness of 0.6 mm, and a second solution treatment was performed at 800 ° C for 30 seconds.

[0092] Thereafter, rolling to a thickness of 0.4 mm or 0.2 mm (second rolling) was performed at room temperature, and an aging treatment (first aging) was performed under predetermined conditions. Furthermore, rolling (third rolling) was performed at room temperature to a thickness of 0.2 mm or 0.1 mm, and aging treatment (second aging) was performed under predetermined conditions. Table 5 shows these manufacturing conditions.

[0093] For the test materials thus prepared, the total number of particles and inclusions per unit area, average crystal grain size, aspect ratio, electrical conductivity, tensile strength, ductility, and The bending strength was determined. These results are shown in Table 6.

[0094] [Table 4]

Table 4

* Means that the chemical composition is outside the range defined in the present invention.

REM (rare earth element): added in the form of misch metal.

Table 5 sffis [009

Rminj of Γ time J means minutes and rhj means hours.

? ¾sl @ (Θ! ”, :: τΘχ〜.

[0097] As shown in Table 6, in Example 2130 of the present invention, the tensile strength, ductility and bending workability were all good. Since the value of the good way B is equal to or more than that of the bad way (below it in terms of the value of B), only the bad way is shown in Table 6. .

[0098] On the other hand, in Comparative Example 31 37, any one of the chemical composition, the average crystal grain size of the copper base matrix and the aspect ratio is out of the range defined in the present invention, and the electrical conductivity, tensile strength, ductility and bending work are performed. Sexuality! / Inferior performance! / Example 3

[0099] Continuous forging and pulling were performed for Alloy No. 14 shown in Table 4, and a mold was forged for Alloy No. 16 by the Darville forging method. The melting was performed in a high-frequency furnace, and charcoal grains were added to cover the entire molten metal for the purpose of preventing oxidation.

[0100] (1) In the horizontal continuous forging of Example 38 of the present invention, the melting furnace power is the pouring power to the holding furnace by pouring, and then charcoal is added in the same manner to prevent acidification, An 80 × 250 mm cross-section piece was obtained by intermittent drawing using a mold. The average drawing speed was 50 mm / min.

[0101] (2) In the drawing method of Example 39 of the present invention, after pouring into the tundish, the acid is prevented with charcoal. The molten metal was poured continuously through the layer covered with. As the saddle type, a water-cooled copper type made of copper alloy was used and continuously drawn at an average speed of 70 mm to obtain a piece having a cross-sectional force of 100 mm × 400 mm.

[0102] (3) In the Darville forging method of Invention Example 40, the mold is held in the state shown in Fig. 2 (a), and after pouring into the mold while ensuring a reducing atmosphere with charcoal powder, This was tilted as shown in Fig. 2 (b) and solidified in the state shown in Fig. 2 (c) to produce a piece having a thickness of 100mm x width 400mm x height 600mm.

[0103] In Examples 38, 39 and 40 of the present invention, the average cooling rates up to 900 ° C after the start of solidification are 2.8 ± 0.3 ° C / s, 2.5 ± 0.3 ° C / s and 2.4 ± 0.2 ° C / s, respectively. s. The cooling rate at the center of the slab during solidification and cooling during continuous fabrication was calculated by the combined use of the temperature history measured on the surface after exiting the saddle and the heat transfer calculation. The cooling rate at the time of darvil fabrication was the same as in Example 1 by using both temperature measurement and heat transfer calculation with thermocouple embedded in the vertical side

[0104] The obtained flakes were surface ground and subjected to hot forging and hot rolling as necessary, and then subjected to solution treatment, cold rolling, solution treatment, cold rolling and cold rolling under the conditions shown in Table 7. Heat treatment was performed, and finally a ribbon with a thickness of 0.2 mm was obtained.

[0105] Using the obtained ribbon, the conductivity, tensile strength, ductility and bending workability were investigated in the same manner as described above. These results are shown in Table 8.

[0106] [Table 7] Table 7 s01c

Γ time J fminj means minutes and fhj means hours.

[0108] As shown in Table 8, high electrical conductivity, tensile strength, elongation and bending workability were obtained in any of the forging methods of Invention Examples 38 to 40, and the method of the present invention was applied to an actual forging machine. I found it applicable.

Example 4

[0109] Alloys Νο.14, 16 and 20 shown in Table 4 were vacuum-melted in a high-frequency melting furnace and placed in a pig iron mold to obtain a piece having a thickness of 150 mm x width 170 mm x length 500 mm . For rare earth elements, elemental elements or misch metals were added. The average cooling rate up to 900 ° C after the start of solidification is 2.0 ± 0.3 ° C./s. After that, rods with a diameter of 20 mm were produced by hot forging and hot rolling. Some were treated with a solution, then surface ground, cold-rolled to a diameter of 10 mm, and heat-treated under specified conditions. Some were further drawn at room temperature to a diameter of 5 mm and heat-treated under specified conditions. Table 9 shows the results of investigations on tensile tests, electrical conductivity, elongation, and heat resistance.

[Table 9]

i * f ¾ ^ ¾ [] QL0111 ^ "

Table 9

Rminj for “hour” means minutes and “hour” means hours.

“◎” in ① means satisfying equation (3).

Excellent lance, excellent strength and heat resistance.

Industrial applicability

[0112] According to the present invention, the balance of tensile strength, formability and electrical conductivity is excellent. However, it is excellent in high-temperature strength, and further, performance required for safety tool materials, that is, thermal conductivity. It is possible to provide a copper alloy excellent in wear resistance and spark resistance, and a method for producing the same.

Brief Description of Drawings

[0113] FIG. 1 is a diagram showing the relationship between electrical conductivity and thermal conductivity.

FIG. 2 is a schematic diagram showing a forging method by the Darville method.

Claims

The scope of the claims

[1] Zn, Sn, Ag, Mn, Fe, Co, Al, Ni, Si, Mo, V, Nb, Ta, W, Ge, Te and Se The total amount is 0.1 to 20% by mass, the balance is copper and impurities, the aspect ratio of the copper-based matrix phase is 5 or less, and the grain size of the precipitates and inclusions present in the alloy is A copper alloy characterized in that the particle size of those having a size of 1 μm or more and the total number of precipitates and inclusions satisfy the following formula (1).

logN≤ 0.4742 + 17.629 X exp (-0.1133 XX)

[2] Mass ^{_{0/0, Ti: 0.01~5%}} , Zr: 0.01~5% and Hf: containing displacement force one to be chosen 0.01% to 5% of Churyoku et al, further, Zn, Sn, Ag, Mn, Fe, Co, Al, Ni ゝ Si ゝ Mo, V, Nb, Ta, W, Ge, Te and Se The balance is copper and impurity power, and the aspect ratio of the crystal grains of the copper base matrix is 5 or less, and among the precipitates and inclusions present in the alloy, the grain size is 1 μm or more. And a total number of precipitates and inclusions satisfying the following formula (1).

logN≤ 0.4742 + 17.629 X exp (-0.1133 XX)

[3] Mass ^_0/0, Cr: contains 0.01 to 5%, more, ZnゝSnゝAgゝMnゝFeゝCo, Al, NiゝSiゝMo, V, Nb, Ta, W, Ge , Te and Se are also selected and contain 0.01-20% in total of one or more selected ones, the balance consists of copper and impurities, and the aspect ratio of the crystal grains of the copper base matrix is 5 or less The particle size of the precipitates and inclusions present in the alloy having a particle size of 1 μm or more and the total number of precipitates and inclusions satisfy the following formula (1): Copper alloy.

logN≤ 0.4742 + 17.629 X exp (-0.1133 XX)

[4] In the copper alloy according to any one of claims 1 to 3, instead of a part of copper, one or more of Mg, Li, Ca and rare earth elements are also selected. A copper alloy containing 0.001 to 2 mass% in total.

[5] In the copper alloy according to any one of claims 1 to 4, in place of a part of copper, P, B, Bi ゝ Tl, Rb, Cs, Sr, Ba, Tc, Re, Medium strength of Os, Rh, In, Pd, Po, Sb, Au, Ga, S, Cd, As and Pb It is characterized by containing 0.0001-3 mass% in total of one or more selected Copper alloy.

[6] The copper alloy according to any one of [1] to [5], wherein the crystal grain size is 0.01 to 35 μm.

[7] A copper alloy having the chemical composition according to any one of claims 1 to 5 is melted and formed, and at least a temperature range from the temperature of the piece immediately after forging to 900 ° C is obtained. The aspect ratio of the crystal grains of the copper base matrix is 5 or less, characterized by performing solution treatment and Z or hot rolling after cooling at a cooling rate of 1 ° C Zs or higher. The method for producing a copper alloy in which the grain size of the precipitates and inclusions present in the alloy with a grain size of 1 μm or more and the total number of precipitates and inclusions satisfy the following formula (1) .

logN≤ 0.4742 + 17.629 X exp (-0.1133 XX)

[8] A piece obtained by melting and forging a copper alloy having the chemical composition according to any one of claims 1 to 5, at least in a temperature range from the piece temperature immediately after forging to 900 ° C. In addition, after cooling at a cooling rate of 1 ° C Zs or higher, solution treatment and Z or hot rolling are performed, and then caulking in a temperature range of 600 ° C or lower. In addition, the aspect ratio of the crystal grains of the copper-based matrix is 5 or less, and among the precipitates and inclusions present in the alloy, the grain size is 1 μm or more, and the precipitates and inclusions. A copper alloy manufacturing method in which the total number of objects satisfies the following formula (1).

logN≤ 0.4742 + 17.629 X exp (-0.1133 XX)

However, N means the total number of precipitates and inclusions per unit area (pieces Zmm ² ), and X means the grain size (μm) of the precipitates and inclusions. A copper alloy having a chemical composition according to any one of claims 1 to 5 is melted and formed, and at least a piece obtained in the temperature range from the piece temperature immediately after the production to 900 ° C is obtained. ! After cooling at a cooling rate of 1 ° C Zs or higher, solution treatment and Z or hot rolling are performed, and then it is checked in a temperature range of 600 ° C or lower, and further 150 to 750 ° C. The aspect ratio of the crystal grains of the copper base matrix is 5 or less, and the grain size of precipitates and inclusions present in the alloy is 1 μm or more. A method for producing a copper alloy in which the particle size of the material and the total number of precipitates and inclusions satisfy the following formula (1).

logN≤ 0.4742 + 17.629 X exp (-0.1133 XX)

The copper according to claim 9, wherein solution treatment and Z or hot rolling, processing in a temperature range of 600 ° C. or lower, and heat treatment held in a temperature range of 150 to 750 ° C. are performed a plurality of times. Alloy manufacturing method.

11. The method for producing a copper alloy according to claim 9, wherein processing is performed in a temperature range of 600 ° C. or less after the last heat treatment.