JP5293996B2 - Dispersion strengthened copper, dispersion strengthened copper manufacturing method, and conductor for electric wire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a dispersion-strengthening copper and a producing method thereof which disperses carbide material and boride material in a basic material and provides the strength and the electric conductivity in good balance, and to provide a conductor for electric wire composed of the dispersion-strengthening copper. <P>SOLUTION: Molten material mixing Cu or Cu alloy as the basic material, compound-forming element, such as Ti, and carbon and boron sources, are heated at the melting point or higher of the carbon-boron source and the above compound-formed elements and C and B of the carbon-boron source, are reacted to produce the carbide and the boride materials. The molten material is stirred and the generated carbide material and the boride material are uniformly dispersed in the molten material and solidified. In this way, the dispersion-strengthening copper, dispersing fine carbide grains and boride grains in the basic material is obtained. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to dispersion-strengthened copper in which carbide particles and boride particles are dispersed in a base material, a method for producing the dispersion-strengthened copper, and a conductor for electric wires made of the dispersion-strengthened copper. In particular, the present invention relates to dispersion strengthened copper having a good balance between strength and electrical conductivity.

  Conventionally, copper or a copper alloy has been used as a conductor material for electric wires. In order to improve strength, dispersion strengthened copper in which ceramic particles such as alumina are dispersed in a base material has been developed. Dispersion strengthened copper is typically mixed and sintered with the above ceramic powder and base metal powder (sintering method), or mixed and cast with ceramic powder in the base metal melt (melting method). Manufactured. In addition, Patent Document 1 discloses a dispersion in which Zr carbide and Zr boride are dispersed by mixing and melting boron and carbon source powder, Zr powder, and copper powder and then cooling (powder metallurgy method). Disclosed reinforced copper.

Japanese Patent Laid-Open No. 11-100625

  However, in the melting method, the ceramic particles are likely to aggregate, so that even if they are stirred, it is difficult to uniformly disperse them, and unevenness in characteristics due to uneven distribution of the particles tends to occur. On the other hand, the sintering method and the powder metallurgy method are not suitable for continuous production, and it is difficult to efficiently produce a material for a conductor for electric wires.

Moreover, although the conductor for electric wires is desired to have high electrical conductivity and high strength, it has not been sufficiently studied for this requirement. In particular, even if the conductor diameter and subdivisions for weight reduction, the development of the wire conductor is a high strength is desired.

  Accordingly, one of the objects of the present invention is to provide dispersion strengthened copper having a good balance between conductivity and strength. Another object of the present invention is to provide a production method capable of continuously producing dispersion strengthened copper. Furthermore, the other object of this invention is to provide the conductor for electric wires which provides electrical conductivity and intensity | strength with sufficient balance.

  The present inventors did not add the ceramic powder as a dispersion material as it is to the molten base metal, but produced it by melting the raw material of the compound as a dispersion material (compound forming element and carbon boron source) together with the raw material of the base material. It was found that by using a molten metal to produce a dispersion material during the manufacturing process, it is possible to continuously produce dispersion-strengthened copper having high electrical conductivity and high strength. Based on this knowledge, the present invention defines a method for producing dispersion strengthened copper by a casting method.

The present invention is a manufacturing method for manufacturing dispersion strengthened copper in which compound particles are dispersed in a base material, and includes the following steps.
(1) A step of preparing a molten metal in which pure Cu or a Cu alloy composed of pure Cu and an additive element, and the following compound forming element and a carbon boron source containing C and B are mixed. The compound forming element is at least one element selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W.
(2) A step of setting the molten metal to be equal to or higher than the melting point of the carbon boron source and reacting a compound-forming element with C and B in the carbon boron source to generate carbides and borides and stirring the molten metal.
(3) A step of cooling and solidifying the molten metal in which the carbide and boride are generated and stirred.

  The dispersion-strengthened copper of the present invention having a structure in which compound particles, specifically, carbide particles and boride particles are uniformly dispersed in a base material made of Cu or a Cu alloy is obtained by the production by the casting method. More specifically, the dispersion strengthened copper of the present invention contains 0.001 to 1.0 mass% of C, 0.001 to 2.0 mass% of B, and 0.004 to 16 mass% of the compound forming element. In the base material, carbide particles substantially composed of C and the compound forming element, and boride particles substantially composed of B and the compound forming element are dispersed. In particular, the dispersion strengthened copper of the present invention includes carbides and borides in which the compound-forming element in the carbide and the compound-forming element in the boride are the same element.

The dispersion-strengthened copper of the present invention having the above configuration has high conductivity and high strength. As described above, since the conductivity and strength are well-balanced, the dispersion-strengthened copper of the present invention can be suitably used as a material for electric wire conductors. In particular, the dispersion-strengthened copper of the present invention is excellent in strength even if it is thinned, and therefore can be suitably used as a conductor material for electric wires that is desired to have a small diameter for the purpose of weight reduction. Further, according to the present invention production process, the present invention dispersion strengthened copper because it is continuously producible, for example, can be produced with good productivity a long material such as a material for electric wire conductor. Hereinafter, the present invention will be described in more detail.

[Dispersion strengthened copper]
<Composition>
《Base material》
The dispersion strengthened copper of the present invention contains pure Cu or a Cu alloy obtained by adding an additive element to pure Cu as a main component (base material). Examples of the additive element include Sn, Ni, Si, Fe, P, Ag, and Cr. For example, a Cu—Sn alloy, Cu—Ni—Si alloy, Cu—Fe—P alloy, Cu—Ag alloy, Cu—Cr alloy, or Cu—Si alloy having a known composition can be used as a base material. Since the strength of the dispersion-strengthened copper of the present invention can be increased by forming a carbide and boride dispersion structure, the content of additive elements can be reduced as compared with the Cu alloys having the known compositions listed above. The dispersion-strengthened copper of the present invention has a composition containing C, B, and a compound-forming element in a base material made of pure Cu or a Cu alloy. Specific compositions are listed below.
Composition (I) 0.001% to 1.0% by mass of C, 0.001% to 2.0% by mass of B, 0.004% to 16% by mass of a compound-forming element, and the balance consisting of Cu and inevitable impurities Composition (II) C contains 0.001% to 1.0% by mass, B contains 0.001% to 2.0% by mass, compound forming elements contain 0.004% to 16% by mass, and further contains a predetermined amount of additive elements And the balance consists of Cu and inevitable impurities

The composition in dispersion strengthened copper is, for example, inductively coupled plasma (ICP: Inductively
Coupled Plasma) Emission spectroscopic analysis and X-ray photoelectron spectroscopy (XPS). The presence of carbides and borides in the dispersion strengthened copper is examined by, for example, X-ray diffraction (XRD) or energy dispersive X-ray analysis (EDX).

《C (carbon) and B (boron)》
Most or all of C and B in the dispersion-strengthened copper of the present invention exists as carbides and borides dispersed in the base material. In the present invention, a part of C and B is allowed to be dissolved in Cu or a Cu alloy or to be precipitated at a grain boundary. The contents of C and B are respectively the total of carbides dispersed in the base material, those forming borides, those dissolved in Cu or Cu alloy, and precipitated in Cu or Cu alloy. To do. When C is less than 0.001% by mass or B is less than 0.001% by mass, carbides and borides are not sufficiently present in the base material, and the effect of improving the characteristics due to dispersion of compound particles cannot be obtained. If C is more than 1.0 mass% or B is more than 2.0 mass%, a large amount of the element is deposited alone at the grain boundary, and conversely, the characteristics are deteriorated. A more preferable content of C is 0.01% by mass or more and 0.5% by mass or less, and a more preferable content of B is 0.1% by mass or more and 1.5% by mass or less.

《Carbide forming element》
The dispersion-strengthened copper of the present invention is a periodic table elements 4A, 5A, and 6A, specifically Ti,
At least one element selected from the group consisting of Hf, V, Cr, Mo, and W is contained as a compound forming element. The compound forming element may be one type or two or more types. When a plurality of types are used, the total content satisfies 0.004% by mass to 16% by mass. Compound-forming elements are elements that are more likely to form carbides and borides than Cu, and most or all of them are present in the matrix as carbides and borides formed by reaction with C and B, respectively. To do. In the present invention, a part of the compound forming element is allowed to be dissolved or precipitated in Cu or Cu alloy. The content of the compound-forming element is the sum of the compound-forming element, the solid-dissolved element, and the precipitated element. When the compound forming element is less than 0.004% by mass, the carbide and boride are not sufficiently present in the base material, and the effect of improving the characteristics due to the dispersion of the compound particles cannot be obtained. When the compound forming element exceeds 16% by mass, the electrical conductivity decreases. A more preferable content of the compound forming element is 0.01% by mass or more and 4.0% by mass or less, and a more preferable element is Ti. Ti has a great effect of improving strength. The preferred content varies depending on the type of compound-forming element. Table 1 shows preferred upper and lower limits for each element. When containing multiple types of compound-forming elements, for example, when using three types of elements, the content of each element is 1/3 of the average value in the range shown in Table 1 for each element. The optimum content of each element may be obtained by conducting an experiment. The content is appropriately adjusted by adjusting the addition amount. When the base material is a Cu alloy, some of the additive elements can be compound forming elements. As a general tendency, the strength increases as the content of the compound-forming element and B, C increases, and the conductivity increases as the content decreases.

<Organization>
<< Carbides and borides >>
In the dispersion strengthened copper of the present invention, a carbide substantially composed of C and the compound forming element and a boride substantially composed of B and the compound element are dispersed in the base material. The carbide is typically composed of C and the compound-forming element, specifically, one or more of TiC, HfC, VC, Cr ₃ C ₂ , Mo ₂ C, and WC. The compound is typically composed of B and the above compound-forming elements, specifically TiB ₂ ,
_{HfB 2, VB 2, CrB,} CrB 2, MoB 2, Mo 2 B 5, MoB, 1 or more W ₂ B ₅ and the like. In addition to the carbides and borides, the carbides and borides are allowed to contain compound forming elements such as Ti as they are, or elements contained in the base material such as Cu and P are allowed to be contained.

  In particular, the dispersion strengthened copper of the present invention includes carbides and borides composed of the same compound forming elements. All carbides and borides may be composed of common compound-forming elements. Since these carbides and borides are higher in hardness and higher in strength than Cu, the dispersion-strengthened copper of the present invention having a structure in which they are dispersed in the matrix is reinforced. In other words, the dispersion-strengthened copper of the present invention has a compound particle-dispersed structure, and it is effective while suppressing the decrease in conductivity without adding the kind of additive element to be dissolved in the base material and increasing the content. The strength is improved. In addition, when the base material of the dispersion-strengthened copper of the present invention is a Cu alloy, a solid solution type alloy (with a small content of additive elements) or an aging type alloy with insufficient strength can be obtained by forming a compound particle dispersed structure. The characteristics of can be improved.

  The total content of the carbide and boride is preferably 0.006 to 19% by mass, and is appropriately adjusted depending on the types of the carbide and boride. The content can be adjusted by adjusting the addition amount of the compound forming element and the addition amount of C or B. Table 2 shows preferable upper limit values and lower limit values of carbides and borides.

  The dispersion-strengthened copper obtained by the production method of the present invention has no coarse compound particles, and both the carbide particles and boride particles are fine. Specifically, the average particle diameter of the carbide particles is 3 μm or less, and the average particle diameter of the boride particles is 5 μm or less. These fine particles are maintained even in a state of a plastic working material (for example, a wire drawing material) obtained by subjecting the dispersion strengthened copper of the present invention to plastic working such as rolling or wire drawing from the state of a solidified material.

  Each particle exists in various shapes such as a spherical shape (circular cross section), an elliptical cross section, and a rectangular cross section. The average particle diameter is obtained by analyzing the image of a micrograph of 3000 μm square of 35 μm square in the cross section of the dispersion strengthened copper of the present invention, measuring the diameter of all particles in this cross section, and taking the average value. As for the diameter of each particle, the diameter of a circle (equivalent circle diameter) equal to this area is calculated from the area of the particle in the cross section, this equivalent circle diameter is taken as the diameter, and the average particle diameter is obtained based on this diameter. In the test examples described later, the average particle diameter is obtained by this method.

[Production method]
<Production of molten metal>
The dispersion-strengthened copper of the present invention is prepared by melting a raw material and preparing a molten metal in which pure Cu or Cu alloy as a base material, the compound forming element, and a carbon boron source containing C and B are mixed. The molten metal may be prepared by mixing all the raw materials and then melting them, or by first preparing a molten metal of Cu or Cu alloy and adding a compound forming element or a carbon boron source to the molten metal. May be. The compound-forming element may be added alone or in a compound containing this element, for example, an alloy with Cu. As the carbon boron source, one that can react with a compound-forming element in the molten metal to form a carbide and a boride is used. The carbon boron source may be a plurality of types in which the carbon source and the boron source are separated, for example, C simple substance (for example, graphite), an alloy or compound containing C (for example, Fe-C alloy, SiC, CaC ₂ etc. Carbides), B alone, alloys and compounds containing B (for example, borides such as Cu-B alloy and B ₄ C) can be used. Yield increases and the variation tends to be smaller when added as an alloy or compound than when added alone. In particular, when boron carbide (B ₄ C) is used as a carbon boron source, it is not necessary to prepare a carbon source and a boron source separately, and no extra elements are contained. It is possible to prevent adverse effects such as melting and lowering the conductivity. Of the carbon boron source dissolved in the base material, elements other than B and C are preferably precipitated in order to prevent a decrease in conductivity.

  The molten metal may be produced in an air atmosphere. However, if the molten metal is produced in an inert gas atmosphere such as nitrogen gas or argon gas, generation of slag (oxide) in the molten metal can be suppressed. When the mixed gas atmosphere is obtained by adding 5 to 15% by volume of hydrogen gas to the inert gas, unavoidable oxygen can be removed.

<Heating of molten metal>
The produced molten metal is heated to a temperature equal to or higher than the melting point of the carbon boron source (if there are a plurality of carbon boron sources, the melting point of the highest melting point). By heating to the said temperature, a carbon boron source can be melt | dissolved completely, C and B in a carbon boron source can fully react with a compound formation element, and a carbide | carbonized_material and a boride can be formed. However, in order to prevent coarsening due to grain growth of the formed carbide and boride, the temperature of the molten metal preferably does not exceed the melting point of the formed carbide and boride. Usually, the melting point of the carbon boron source is higher than the melting point of Cu or Cu alloy as the base material, and therefore the base material is in a molten state by heating to a temperature higher than the melting point of the carbon boron source.

<Agitating molten metal>
The molten metal is stirred with a stirring fin or the like together with the above heating. Stirring can promote the reaction between C and B and compound-forming elements, and the carbides and borides formed in the molten metal are uniformly dispersed in the base material, so that the carbide particles and the boride particles are uniform in the base material. The dispersion-strengthened copper according to the present invention can be produced.

<Solidification of molten metal>
The heated and stirred molten metal is solidified to produce a solidified material. Rapid cooling by increasing the cooling rate during solidification, specifically 100 ° C / sec or higher, especially 150 ° C / sec or higher, suppresses the growth of the generated compound particles and prevents the appearance of coarse particles. And the compound particles can be made finer. And by rapidly cooling, the molten metal in which the compound particles are uniformly dispersed by stirring can be solidified almost as it is. Therefore, a dispersion strengthened copper having a structure in which fine carbide particles and boride particles are uniformly dispersed is obtained. Rapid cooling satisfying the above cooling rate can be realized by performing forced cooling, for example, water cooling or blowing cold air.

<Heat treatment>
After the solidification step, heat treatment may be appropriately performed. For example, heat treatment is performed on the solidified material, or a plastic processed material obtained by subjecting the solidified material to plastic processing such as wire drawing (the drawn material after drawing or the processed material during drawing). When performing multi-pass wire drawing after solidification before wire drawing, the following effects (1) to (3) can be obtained by performing at least one heat treatment either during wire drawing or after wire drawing. can get. The obtained solidified material has a structure in which fine compound particles are uniformly dispersed in the base material, so that when the heat treatment is performed after solidification, during wire drawing, or after wire drawing, the pin of particles The stopping effect can prevent the coarsening of the crystal grains that make up the base metal, causing the coarse crystal grains to become the starting point of cracking and breaking during wire drawing, and the toughness of the wire drawing material to decrease due to the coarse crystal grains. Can be prevented.

(1) When carbon, boron, and a compound-forming element are dissolved in the solidified material, the formation of the compound can be promoted by heat treatment to increase the compound particles that contribute to dispersion strengthening.
(2) When the base material is an aging type alloy or a two-phase type alloy, the heat treatment promotes the precipitation of the additive element dissolved in the base material, thereby increasing the conductivity and strength of the base material itself.
(3) When heat treatment is performed on a wire drawing material or a work piece in the middle of wire drawing, distortion due to wire drawing can be removed and elongation of the wire drawing material can be recovered.

  The heating temperature for the heat treatment is preferably 250 ° C. or higher. If it is less than 250 degreeC, the movement of the atom in a heating object material is slight, and the said effect is not fully acquired. More preferably, it is 250-650 degreeC. The holding time is preferably 0.1 to 10 hours.

  By the manufacturing method described above, the dispersion strengthening of the base material can be effectively performed, and the dispersion-strengthened copper of the present invention having a balance between strength and electrical conductivity can be manufactured. Specifically, a dispersion strengthened copper having a tensile strength of 550 MPa or more and an electrical conductivity of 40% IACS or a dispersion strengthened copper having a tensile strength of 520 MPa or more and an electrical conductivity of 90% IACS or more can be produced.

  In the production method of the present invention, Zr, Nb, Ta can also be used as a compound forming element. The preferable content of each element is, in mass%, Zr: 0.008 to 7.6, Nb: 0.008 to 7.7, Ta: 0.015 to 15.1. Further, specific forms when these elements are added include Cu-Zr alloy ingots (Zr content: 30% by mass), Nb flakes, and Ta grains.

<Application>
Since the dispersion-strengthened copper of the present invention has high electrical conductivity and high strength, it can be suitably used as a conductor material for electric wires. The drawn material obtained by drawing the solidified material made of the dispersion-strengthened copper of the present invention to have a desired diameter is used as a conductor. This conductor for electric wire has high strength even if it has a small diameter of φ0.2 mm or less, and satisfies tensile strength: 550 MPa or more and conductivity: 40% IACS or more. Such a conductor for electric wires can be used, for example, as a conductor for electric wires for wire harnesses.

  The dispersion-strengthened copper of the present invention and the conductor for electric wires made of this dispersion-strengthened copper have a good balance between strength and electrical conductivity. In addition, the production method of the present invention can produce the dispersion-strengthened copper of the present invention having a good balance between strength and electrical conductivity with good productivity.

[Test example]
Dispersion strengthened copper in which carbide and boride were dispersed in a base material made of pure copper was prepared, and the electrical conductivity and tensile strength were examined.

<Sample Nos. 1 to 4>
Pure Cu (OFC) grains, sponge Ti grains as a compound forming element, and boron carbide grains (B ₄ C) as a carbon boron source were prepared, put in a crucible, and melted in an arc melting furnace. Melting was performed in an argon atmosphere to prevent oxidation of the raw material. The obtained molten metal was heated to a melting point of boron carbide (about 2350 ° C.) or higher and stirred with a stirring fin. This mixed molten metal was cast into a water-cooled Cu mold and solidified by quenching at a cooling rate of 100 ° C./sec or higher (180 ° C./sec) to obtain a solidified material having a width of 40 mm × thickness 20 mm × length 70 mm. Different amounts of Ti and B ₄ C were added to obtain solidified materials having different compositions (Sample Nos. 1 to 4). The obtained solidified material was subjected to surface cutting to obtain a rod-like body having a diameter of φ12 mm, and this rod-like body was swaged to φ6 mm. The obtained processed material having a diameter of 6 mm was drawn to a diameter of 0.2 mm. Sample No. 1 was subjected to a heat treatment (aging treatment) at 450 ° C. for 8 hours (cooling: furnace cooling), and Samples No. 2 to 4 were kept as the wire drawing material.

<Sample No.100>
Pure Cu (OFC) grains, sponge Ti grains as a compound forming element, and graphite as a carbon source were prepared and placed in a crucible, and melted in an arc melting furnace in the same manner as in Samples Nos. 1 to 4. The obtained molten metal was heated to 2300 ° C. and stirred with a stirring fin, and then a solidified material having the same size was obtained as in Samples Nos. 1 to 4 (Sample No. 100). The obtained solidified material was used in the same manner as in Samples Nos. 1 to 4 to produce a wire drawing material having a diameter of 0.2 mm, and the same aging treatment as in Sample No. 1 was performed.

<Sample No. 101>
Prepare pure Cu (OFC) grains, sponge Ti grains as compound-forming elements, and Cu-B alloy (B content: 2% by mass) as boron source, put them in a crucible, and arc as in Sample Nos. 1 to 4 Melting was performed in a melting furnace. The obtained molten metal was brought to 1150 ° C. and stirred with a stirring fin, and then a solidified material having the same size was obtained in the same manner as in Samples Nos. 1 to 4 (Sample No. 101). The obtained solidified material was made into a wire drawing material having a diameter of 0.2 mm in the same manner as in Samples Nos. 1 to 4.

  The composition of each obtained solidified material was examined by ICP emission spectroscopic analysis. The results are shown in Table 3.

Further, the cross section of each obtained solidified material was observed with a scanning electron microscope (SEM) attached with EDX. FIG. 1 shows micrographs (35 μm square, 3000 times) of cross sections of the solidified materials of Sample Nos. 1 to 4. In FIG. 1, the light gray portion (relatively bright portion as a background) is a base material, and the granular dark gray portion (relatively dark portion) is carbide (TiC) and boride (TiB ₂ ). The presence of the compound was confirmed by EDX. As can be seen from FIG. 1, in any of the solidified materials of Sample Nos. 1 to 4, fine carbides and borides are uniformly dispersed in the base material. Further, FIG. 1 shows that C, B, and Ti contained in the base material are substantially present as carbide (TiC) and boride (TiB ₂ ). Further, the average particle size of carbide particles and boride particles was measured for sample Nos. 1 to 4, for example, sample No. 3 was carbide particles: 0.5 μm, boride particles: 1.2 μm, other The sample also had carbide particles of 3 μm or less and boride particles of 5 μm or less.

  The tensile strength (MPa) and electrical conductivity (% IACS) of the wire Nos. 1 to 4 and 100, 101 and the heat-treated materials were examined. The results are shown in Table 4.

  As shown in Table 4, Samples Nos. 1 to 4 have high electrical conductivity and tensile strength. In particular, Sample Nos. 2 to 4 have very high electrical conductivity and high strength. Since Sample No. 1 has a large amount of Ti, although its conductivity is lower than that of Sample Nos. 2 to 4, a decrease in conductivity is reduced by applying an aging treatment. It can also be seen that Sample No. 1 is higher in strength than Sample No. 100 having the same conductivity.

  The reason for such a result is presumed that the wire drawing material and the heat treatment material of Sample Nos. 1 to 4 maintain a structure in which fine carbide particles and boride particles are uniformly dispersed. In addition, it is presumed that during the heat treatment after wire drawing, the growth of crystal grains constituting the base material could be suppressed by the pinning effect of these fine carbides and borides. Thus, it is considered that Samples Nos. 1 to 4 having a good balance of strength and conductivity can be suitably used for the conductor for electric wires. In the above test example, a short material was produced for the test, but a long material can also be produced by continuous casting.

  In the above test example, each raw material can be changed as follows.

《Base material》
When the base material is a Cu alloy, instead of the pure Cu (OFC) grains, a Cu-Cr alloy ingot (Cr content: 5 mass%), a Cu-Si alloy ingot (Si content: 11) Mass%), Cu—Sn alloy ingots (Sn content: 0.3 mass%), and the like.

<Compound-forming elements>
Instead of the sponge Ti particles or in addition to the sponge Ti particles, for example, sponge Hf particles, vanadium flakes, Cr particles, Mo powder (particle size of about 300 μm), W powder (particle size of about 150 μm) is used. it can. Since metals having a high melting point such as Mo and W are difficult to melt, it is desirable to heat them over time using a powder having a small particle size.

  The above-described embodiment can be appropriately changed without departing from the gist of the present invention, and is not limited to the above-described configuration. For example, the content of carbon and boron and the type and content of compound forming elements can be changed.

  The dispersion-strengthened copper of the present invention can be suitably used as a material for electric wire conductors that require high strength and high electrical conductivity. The manufacturing method of dispersion strengthened copper of this invention can be utilized suitably for manufacture of the said high intensity | strength and high conductivity dispersion strengthened copper. This invention conductor for electric wires can be utilized suitably for the conductor of the electric wire for wire harnesses, for example.

It is a micrograph of a cross section of dispersion strengthened copper in which carbide and boride are dispersed in a base material, (I) is sample No. 1, (II) is sample No. 2, (III) is sample No. 3, (IV ) Shows Sample No.4.

Claims (6)

A dispersion strengthened copper in which compound particles are dispersed in a base material,
The base material is made of Cu or Cu alloy,
C 0.001 wt% to 1.0 wt% or less, the B 0.001 wt% 2.0 wt% or less, Ti, Hf, V, Cr, Mo, and W and at least one compound forming element selected from the group consisting of 0.004 contains more mass% 16 mass% or less,
Substantially of carbides consisting of C and the compound forming element particles, substantially B and the compound forming elements consisting of boride particles are dispersed in said base material,
Look containing a carbide and boride and the compound forming element in said carbide compound forming element in said borides are the same element,
The carbide particles have an average particle size of 3 μm or less,
The average particle size of the boride particles is 5 μm or less,
Dispersion strengthened copper with a tensile strength of 520 MPa or more . The same compound forming element, the dispersion strengthened copper according to 請 Motomeko 1 Ru Ti der. 3. The dispersion strengthened copper according to claim 1, wherein a content of the compound forming element is 0.67% by mass or less. Claims 1 to one Kana that conductive line conductor a dispersion strengthened copper according to one of claims 3. A dispersion-strengthened copper manufacturing method for manufacturing dispersion-strengthened copper in which compound particles are dispersed in a base material,
Pure Cu, or a Cu alloy composed of pure Cu and an additive element, and at least one compound forming element selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W, Preparing a molten metal mixed with a carbon boron source containing C and B;
A step of reacting a compound-forming element and C and B in the carbon boron source to make the molten metal above the melting point of the carbon boron source to produce carbides and borides, and stirring the molten metal;
The carbides and produce and a method of manufacturing process and the comprises that distributed strengthened copper to solidify by cooling with molten metal 100 ° C. / sec or more cooling rate went agitation of the boride.   Further comprising a heat treatment step after the solidification step,
  6. The method for producing dispersion strengthened copper according to claim 5, wherein the heat treatment is performed at a heating temperature of 250 ° C. or higher and 650 ° C. or lower and a holding time of 0.1 hour or longer and 10 hours or shorter.