JP2012087368A - Clad material excellent in workability and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a clad material with high productivity and excellent in terms of conductivity, softening temperature and surface quality, and to provide a method for manufacturing the same.SOLUTION: The clad material is obtained by bonding different metal materials, wherein at least one of the metal materials is a dilute copper alloy material comprising more than 2 mass ppm oxygen and an additive element chosen from the group consisting of Ti, Mg, Zr, Nb, Ca, V, Ni, Mn, and Cr and the balance being unavoidable impurities and copper. The method for manufacturing the dilute copper alloy material for the clad material comprises: manufacturing a wire rod from a pre-rolled material by a twin-roll continuous casting and rolling method or a Properzi continuous casting and rolling method employing a casting temperature of 1,100-1,320°C; and subjecting the wire rod to hot rolling wherein rolling by the first roll is carried out at ≤880°C and rolling by the final roll is carried out at ≥550°C.

Description

  The present invention relates to a novel clad material excellent in workability and a method for producing the same.

  In recent industrial products such as electronic devices and automobiles, copper wires are often used severely. In order to address these needs, a dilute copper alloy material that can be manufactured by a continuous casting and rolling method, etc., and has higher conductivity than pure copper while maintaining conductivity and elongation properties at pure copper level has been developed. .

  As a dilute copper alloy material, as a general-purpose soft copper wire and a soft copper material that requires softness, a soft conductor having an electrical conductivity of 98% or more and further 102% or more has been demanded. Substitutes for wiring materials for consumer solar cells, conductors for enameled wires for motors, soft copper materials for high temperatures used at 200-700 ° C, molten solder plating materials that do not require annealing, copper materials with excellent heat conduction, and high-purity copper alternatives It can be used as a material to meet these broad needs.

  The material used as a dilute copper alloy material is based on the technology that controls oxygen in copper to 10 mass ppm or less, and a small amount of metal such as Ti is added to the copper atom in the base. It is expected that a dilute copper alloy material having high productivity and excellent electrical conductivity, softening temperature and surface quality can be obtained by solid solution in atomic form.

  Conventionally, regarding softening, as shown in Non-Patent Document 1, a sample in which 4 to 28 mol ppm of Ti is added to electrolytic copper (99.996% by mass or more) has a faster softening than a sample in which Ti is not added. The results that occur are being obtained. We conclude that this is due to a decrease in solute S due to Ti sulfide formation.

  Patent Documents 1 to 3 propose that continuous casting is performed in a continuous casting apparatus using a dilute alloy obtained by adding a trace amount of Ti to oxygen-free copper.

  Here, methods for lowering oxygen by a continuous casting and rolling method are also known as shown in Patent Documents 4 and 5.

  In Patent Document 6, when a copper material is directly produced from a molten copper by a continuous casting and rolling method, a trace amount of metal such as Ti, Zr, and V is added to a molten copper having an oxygen content of 0.005% by mass or less (0.0. It has been proposed to lower the softening temperature by adding (0007 to 0.005 mass%). However, in Patent Document 6, the study on the electrical conductivity has not been made, and the manufacturing condition range in which the electrical conductivity and the softening temperature are compatible is unknown.

  On the other hand, Patent Document 7 proposes a method for producing an oxygen-free copper material having a low softening temperature and high conductivity, and in an upward pulling continuous casting apparatus, an oxygen amount of 0.0001% by mass or less. There has been proposed a method for producing a copper material from a molten copper obtained by adding a trace amount (0.0007 to 0.005 mass%) of a metal such as Ti, Zr, or V to copper.

  However, as described above, none of the patent documents discusses a material containing a small amount of oxygen, such as a base material of a diluted copper alloy material, that is, a material containing an oxygen concentration in the order of ppm.

  In addition, various investigations have been made on clad materials in which copper and dissimilar metals are integrated. For example, Cu and Al clad having both high conductivity and thermal conductivity of copper (Cu) and light weight characteristics of aluminum (Al). Application of the material to a heat sink used for cooling a semiconductor device, a case for an electronic device, and the like is being studied.

  As a modification of the Cu and Al clad material, a structure in which Ni or Ag is disposed as an intermediate layer between Cu and Al has been proposed (Patent Documents 8, 9, and 10).

  As a general method for producing Cu and Al clad material, there is a method by hot or cold rolling. In the case of hot rolling, heat applied at the time of bonding of Cu foil and Al foil, and Cu and Al clad. Due to the heat applied to soften the material after processing the material to a predetermined thickness, an intermetallic compound of Cu—Al is formed at the connection interface between Cu and Al. In the case of cold rolling, since a higher pressure (working degree) than hot rolling is required to bond Cu and Al, a material cured by bonding and processing to a predetermined thickness is used. In order to soften, a higher heat treatment temperature or a longer time is required. Since Cu and Al intermetallic compounds formed by these heat treatments have brittle properties, the thicker the material, the lower the strength reliability when using the material. In addition, the presence of this intermetallic compound causes a crack at the interface between Cu and Al during pressing, bending and deep drawing, and remarkably deteriorates the workability of the material.

  Patent Documents 8, 9, and 10 propose the structures of Cu and Ni and Al and Cu and Ag and Al in order to suppress the formation of Cu / Al intermetallic compounds. Since expensive Ni and Ag are used, the material cost increases. Also, for example, when Cu, Al, and CU with Cu disposed on both sides of Al are prepared, Cu, Ni, Al, Ni, Cu, Cu, Ag, Al, Ag, Cu, and five layers of clad or plating Therefore, the thickness control and connection stability of each layer are complicated, and the manufacturing cost is significantly increased.

JP 2001-264110 A JP 2002-104629 A JP 2002-163330 A JP 2002-120050 A JP 2001-314950 A JP 2006-274384 A JP 2008-255417 A JP 54-39342 A Japanese Patent Laid-Open No. 11-156995 JP 2004-1069 A

Suzuki, Hisashi, Mikihiro Kanno: Iron and Steel (1984) 15 1977-1983

  Therefore, in industrial products such as electronic devices and automobiles, it has been desired to study practical dilute copper alloy wires having high productivity and excellent electrical conductivity, softening temperature, and surface quality and their compositions.

  Further, when considering the production method, as described above, a method for softening copper by adding Ti to oxygen-free copper by continuous casting is known, but this is a hot process after producing a cast material as a cake or billet. Wire rods are made by extrusion and hot rolling. For this reason, the manufacturing cost is high, and there is a problem in economical efficiency for industrial use.

  In addition, a method of adding Ti to oxygen-free copper using an upward pulling continuous casting apparatus is known, but this also has a problem in terms of economy because of a slow production rate.

  Therefore, the inventors examined an SCR continuous casting and rolling system (South wire Continuous Rod System) excellent in economic efficiency.

  In the SCR continuous casting and rolling method, a base material is melted into a molten metal in a melting furnace of an SCR continuous casting and rolling apparatus, and a desired metal is added to the molten metal to be melted. (For example, φ8 mm) is prepared, and the rough drawing wire is drawn to, for example, φ2.6 mm by hot rolling. Further, it can be similarly processed to a size of φ2.6 mm or less, a plate material, and a deformed material. Further, it is effective to roll a round wire rod into a square shape or an irregular shape, and it is also possible to produce a deformed material by conform extrusion molding of a cast material.

  As a result of investigations by the present inventors, when using SCR continuous casting and rolling, surface scratches are likely to occur with tough pitch copper as the base material, and the softening temperature fluctuates and the formation of titanium oxide is unstable depending on the addition conditions. I found out that

  And when examined using oxygen-free copper of 0.0001% by mass or less, the conditions satisfying the softening temperature, electrical conductivity, and surface quality are in a very narrow range, and there is a limit to the lowering of the softening temperature. Therefore, a decrease in softening temperature comparable to that of high-purity copper was desired.

  An object of the present invention is to provide a clad material that solves the above-described problems, has high workability and productivity, and is excellent in conductivity, softening temperature, and surface quality, and a method for manufacturing the same.

  Another object of the present invention is to provide a dilute copper alloy material for clad capable of suppressing the formation of intermetallic compounds at the interface at a low cost, a dilute copper alloy plate and clad material using the same, and a method for producing the same. There is to do.

  The present invention provides a clad material formed by joining different metal materials, wherein one of the different metal materials is selected from the group consisting of Ti, Mg, Zr, Nb, Ca, V, Ni, Mn, and Cr. It is a dilute copper alloy material containing an element and oxygen in an amount exceeding 2 mass ppm, and the balance being an inevitable impurity and copper.

  The reason why the elements selected from the group consisting of Ti, Mg, Zr, Nb, Ca, V, Ni, Mn, and Cr are selected as the additive elements is that these elements are active elements that are easily combined with other elements. This is because S can be trapped because it is easily bonded to S, and the copper base material (matrix) can be highly purified. One or more additive elements may be included. Also, other elements and impurities that do not adversely affect the properties of the alloy can be included in the alloy.

  Further, in the preferred embodiment described below, it is explained that the oxygen content exceeds 2 mass ppm and is preferably 30 mass ppm or less, but depending on the addition amount of the additive element and the S content, In the range having the properties of the alloy, it can contain more than 2 mass ppm and 400 mass ppm.

  According to the present invention, one of the dissimilar metal materials contains 2 to 12 massppm of sulfur, 30 mass ppm or less exceeding 2 mass ppm of oxygen and 4 to 55 mass ppm of Ti, and a softening temperature of 130 to 148 with a thickness of 0.8 mm. It is preferable that it is ° C.

In the present invention, the sulfur and Ti mainly form compounds or aggregates in the form of TiO, TiO ₂ , TiS, and Ti—O—S, and a small amount of the sulfur and Ti form the diluted copper alloy material. In addition, the particle diameter of the compound or aggregate is 200 nm or less for the TiO, 1000 nm or less for the TiO ₂ , 200 nm or less for the TiS and 300 nm or less for the Ti—O—S, It is preferable that 90% or more of the particles having a size of 500 nm or less are distributed in the crystal grains of the diluted copper alloy material.

  In the present invention, the other metal material is preferably pure Al.

  The present invention contains an additive element selected from the group consisting of Ti, Mg, Zr, Nb, Ca, V, Ni, Mn and Cr, and oxygen in an amount exceeding 2 mass ppm, with the balance being inevitable impurities and A dilute copper alloy plate made of copper is made into a molten metal at a casting temperature of 1100 to 1320 ° C. by continuous casting and rolling, and a cast material is produced. A method of manufacturing a clad material, comprising: a step of bonding the dilute copper alloy plate and the dissimilar metal plate; and a heat treatment step of applying a heat treatment after the bonding.

  The hot rolling temperature is such that the rolling temperature at the first rolling roll is 880 ° C. or lower, the rolling temperature at the final rolling roll is 550 ° C. or higher, and the heating temperature in the heat treatment step is 130 to 190 ° C. It is preferable that the heating time is 0.5 to 5 hours, and that the dilute copper alloy sheet contains sulfur 2 to 12 massppm, oxygen exceeding 2 mass ppm and 30 mass ppm or less and Ti 4 to 55 mass ppm.

  In the present invention, the copper, which is the base of the dilute copper alloy material used as the clad material, is dissolved in a shaft furnace, and is then subjected to sulfur, a constituent element of the dilute alloy, under a reducing system such as a reducing gas (CO) atmosphere shield It can be manufactured by rolling after casting while controlling the concentration, Ti concentration and oxygen concentration.

  A dilute copper alloy material according to the present invention is manufactured by a twin roll type continuous casting rolling and a propelty type continuous casting rolling method at a casting temperature of 1100 to 1320 ° C. to produce a wire rod, and the wire rod is hot rolled and The hot rolling temperature can be produced by hot rolling with the temperature at the first rolling roll being 880 ° C. or lower and the temperature at the final rolling roll being 550 ° C. or higher.

First, the present invention uses an SCR continuous casting equipment, has few surface scratches, has a wide manufacturing range, can be stably produced, and is softened at a processing degree of 90% for a wire rod (for example, diameter φ8 mm → φ2.6 mm). Temperature is 148 ° C or less and conductivity is 98% IACS (conductivity with 100% of Universal Anneld Copper Standard resistivity 1.7241 × 10 ⁻⁸ Ωm), 100% IACS, and further 102% IACS It is to obtain a dilute copper alloy material as a satisfactory soft copper material, and to obtain a manufacturing method thereof.

  At this time, for high-purity copper (6N, purity 99.9999%), the softening temperature at a processing degree of 90% is 130 ° C. Accordingly, a dilute copper alloy material capable of stably producing soft copper having a soft material having a softening temperature of 130 ° C. or higher and 148 ° C. or lower and having a conductivity of 98% IACS or more, 100% IACS or more, and a conductivity of 102% IACS or more. It is an object of the present invention to obtain the raw material and its manufacturing conditions.

  Here, high purity copper (4N) having an oxygen concentration of 1 to 2 mass ppm was used, and a small continuous casting machine (small continuous casting machine) was used in the laboratory, and the molten metal was manufactured from a molten metal with several mass ppm added to the molten metal. When the 8 mm rod is 2.5 mm t (working degree 90%) and the softening temperature is measured, it is 160 to 168 ° C., and the softening temperature is not lower than this. The conductivity is about 101.7% IACS. Therefore, it was found that even when Ti was added at a low oxygen concentration, the softening temperature could not be lowered, and the electrical conductivity of high purity copper (6N) was worse than 102.8% IACS.

  This is considered to be due to the fact that sulfur is contained in several mass ppm or more as an inevitable i impurity during the manufacture of molten metal, and the sulfide such as TiS is not sufficiently formed with this sulfur and titanium, so that the softening temperature does not decrease. .

Therefore, in the present invention, in order to lower the softening temperature and improve the electrical conductivity, the two measures have been studied and the two effects have been combined to achieve the goal.
(a) Increase the oxygen concentration of the material to an amount exceeding 2 mass ppm and add titanium. Thereby, it is considered that TiS, titanium oxide (TiO ₂ ) and Ti—O—S particles are first formed in the molten copper (see the SEM images in FIGS. 1 and 3 and the analysis results in FIGS. 2 and 4). ). In FIGS. 2, 4, and 6, Pt and Pd are vapor deposition elements for observation. The particle size of the TiS particles in FIG. 1 is about 150 nm, and the particle size of the TiO ₂ particles in FIG. 3 is about 1000 nm.
(b) Next, the hot rolling temperature is set lower than the normal copper production conditions (initial rolling temperature 950 ° C. to final rolling temperature 600 ° C.) (first rolling temperature 880 to final rolling temperature 550 ° C.). By doing so, dislocations are introduced into the copper so that S is easily deposited. As a result, precipitation of S on dislocations or precipitation of S with titanium oxide (TiO ₂ ) as nuclei, as an example, forms Ti—O—S particles, etc., similar to molten copper (SEM image of FIG. 5 and , See analysis results in FIG. 6). The particle diameter of the Ti—O—S particles in FIG. 5 is about 300 nm. FIGS. 1-6 evaluate the cross section of φ8 mm copper wire (wire rod) having the oxygen concentration, sulfur concentration, and Ti concentration shown in the third row from the top in Example 1 of Table 1 by SEM observation and EDX analysis. It was. The observation conditions were an acceleration voltage of 15 keV and an emission current of 10 μA.

  According to (a) and (b), a copper rod that crystallizes and precipitates sulfur in copper and satisfies the softening temperature and electrical conductivity after cold wire drawing can be obtained.

Next, in this invention, it is set as (1)-(4) as manufacturing conditions with SCR continuous casting rolling equipment.
(1) Alloy composition When obtaining a soft copper material having an electrical conductivity of 98% IACSS or more, it contains 3 to 12 mass ppm of sulfur, more than 2 mass ppm and not more than 30 mass ppm of oxygen, and 4 to 55 mass ppm of Ti, and the balance. However, a rod (rough-drawing material) is manufactured from a dilute copper alloy material composed of unavoidable impurities and copper (base material). Since oxygen exceeding 2 mass ppm and not more than 30 mass ppm is contained, this embodiment is directed to so-called low oxygen copper (LOC).

  Here, in order to obtain a soft copper material having an electrical conductivity of 100% IACS or higher, pure copper containing inevitable impurities is added to 2-12 mass ppm of sulfur, more than 2 mass ppm, less than 30 mass ppm of oxygen, and 4-37 mass ppm. A dilute copper alloy material containing Ti is preferably used as the rod.

  Furthermore, when obtaining a soft copper material having an electrical conductivity of 102% IACS or higher, pure copper containing inevitable impurities contains 2 to 12 mass ppm of sulfur, oxygen of more than 2 mass ppm, oxygen of 30 mass ppm or less, and Ti of 4 to 25 mass ppm. It is preferable to use a dilute copper alloy material containing a rod.

  Usually, in the industrial production of pure copper, sulfur is taken into copper when producing electrolytic copper, so it is difficult to make sulfur 3 mass ppm or less. The upper limit of the sulfur concentration of general-purpose electrolytic copper is 12 mass ppm.

As described above, if the amount of oxygen to be controlled is small, the softening temperature is unlikely to decrease, so it is set to 2 mass ppm or more. Further, if there is too much oxygen, surface scratches are likely to occur in the hot rolling process, so it is set to 30 mass ppm or less.
(2) Dispersed material It is desirable that the dispersed particles have a small size and are distributed a lot. The reason is that the size is small and the number is large because it functions as a sulfur deposition site.

Sulfur and titanium form compounds or aggregates in the form of TiO, TiO ₂ , TiS, Ti—O—S, and the remaining Ti and S are present in the form of a solid solution. In terms of particle size, TiO is 200 nm or less, TiO ₂ is 1000 nm or less, TiS is 200 nm or less, and Ti—O—S is 300 nm or less and is dispersed in the crystal grains of the copper alloy. A crystal grain means the crystal structure of copper.

However, since the size of the formed particles changes depending on the holding time of the molten copper during casting and the cooling condition, it is necessary to set casting conditions.
(3) Continuous casting and rolling conditions The SCR continuous casting and rolling system melts the base material into a molten metal in the melting furnace of the SCR continuous casting and rolling apparatus, and puts the desired metal into the molten metal. The melted wire is added, melted, a rough drawn wire (for example, φ8 mm) is produced using the molten metal, and the roughed wire is drawn to, for example, φ2.6 mm by hot rolling. Further, it can be similarly processed to a size of φ2.6 mm or less, a plate material, and a deformed material. Further, it is effective to roll a round wire rod into a square shape or an irregular shape, and it is also possible to produce a deformed material by conform extrusion molding of a cast material.

By SCR continuous casting and rolling, a rod is manufactured with an ingot rod working degree of 90% (30 mm) to 99.8% (5 mm). As an example, a method of making a rod of 8 mmt with a working degree of 99.3% is used.
(A) Molten copper temperature in a melting furnace shall be 1120 degreeC or more and 1320 degrees C or less. When the temperature of the molten copper is high, blowholes increase, scratches are generated, and the particle size tends to increase. The reason why the temperature is set to 1120 ° C. or higher is that copper is easily solidified and the production is not stable, but the molten copper temperature is preferably as low as possible.
(B) As for the hot rolling temperature, the rolling temperature at the first rolling roll is preferably 880 ° C. or lower, and the rolling temperature at the final rolling roll is preferably 550 ° C. or higher.

  Unlike normal pure copper production conditions, crystallization of sulfur in molten copper and precipitation of sulfur during hot rolling are issues, so in order to reduce the solid solution limit that is the driving force, The temperature and the hot rolling temperature are preferably (a) and (b).

  The conventional hot rolling temperature is such that the rolling temperature at the first rolling roll is 950 ° C. or lower and the rolling temperature at the final rolling roll is 600 ° C. or higher. In order to reduce the solid solution limit, The rolling temperature at the first rolling roll is set to 880 ° C. or lower, and the rolling temperature at the final rolling roll is set to 550 ° C. or higher.

The reason why the temperature is set to 550 ° C. or higher is that the product is not a product because there are many rod scratches below this temperature. The hot rolling temperature is preferably as low as possible, with the rolling temperature at the first rolling roll being 880 ° C. or lower and the rolling temperature at the final rolling roll being 550 ° C. or higher. By doing so, the softening temperature (after processing to φ8 mm to φ6 mm) is infinitely close to high-purity copper (6N, softening temperature 130 ° C.).
(C) Conductivity of a wire rod of φ8 mm size is 98% IACS or more, 99% IACS or more, and further 102% IACS or more, and the softening temperature of the wire rod (for example, φ2.6 mm) after cold drawing is 130 ° C. A dilute copper alloy wire or plate-like material having a temperature of ˜148 ° C. can be obtained.

  In order to use it industrially, it is necessary to use 98% IACS or more in the industrially used soft copper wire produced from electrolytic copper, and the softening temperature is 148 ° C. or less in view of its industrial value. The softening temperature when Ti is not added is 160 to 165 ° C. Since the softening temperature of high-purity copper (6N) was 127 to 130 ° C., the limit value is set to 130 ° C. from the obtained data. This slight difference is in inevitable impurities not found in high purity copper (6N).

The conductivity is about 101.7% IACS at the level of oxygen-free copper, and 102.8% IACS for high-purity copper (6N), so that the conductivity is as close to high-purity copper (6N) as possible. Is desirable.
(4) Atmosphere and additive conditions in casting Copper was controlled so as to be in a reduced state after melting in the shaft furnace, that is, in the reducing gas (CO) atmosphere, the sulfur concentration of the constituent element of the dilute alloy, A method of stably producing a rod to be cast and rolled by controlling the Ti concentration and oxygen concentration is preferable. Since the copper oxide is mixed and the particle size is large, the quality is lowered.

Here, the reason for selecting Ti as an additive is as follows.
(A) Ti is easily bonded to sulfur in molten copper to form a compound.
(B) It can be processed and handled more easily than other additive metals such as Zr.
(C) It is less expensive than Nb or the like.
(D) It is because it is easy to precipitate using an oxide as a nucleus.

  As described above, the diluted copper alloy material for cladding according to the present invention has high productivity, and it is possible to obtain a practical diluted copper alloy material excellent in conductivity, softening temperature, and surface quality.

  In addition, the present invention does not require the formation of a so-called barrier layer that suppresses the formation of an intermetallic compound of Cu and Al as in the prior art, but as long as it does not adversely affect the alloy, plating between dissimilar metal materials is possible. It does not prevent the formation of an intermediate layer such as a layer.

  Moreover, in the above-mentioned this invention, although the rod was produced by the SCR continuous casting rolling method and the soft material was produced by hot rolling, it demonstrated by the twin roll type continuous casting rolling method or the propelty type continuous casting rolling method. Can be manufactured.

  According to the present invention, it is possible to provide a practical dilute copper alloy material for clad having high workability and productivity, excellent conductivity, softening temperature, and surface quality, and a clad material using the same and a method for producing the same. The effect is demonstrated.

  Further, according to the present invention, when different kinds of metal materials are joined to each other, the intermetallic compound formed at the interface can be controlled by an inexpensive method.

It is a figure which shows the SEM image of a TiS particle | grain. It is a figure which shows the analysis result of FIG. Is a view showing an SEM image of the TiO ₂ particles. It is a figure which shows the analysis result of FIG. It is a figure which shows the SEM image of Ti-O-S particle | grains. It is a figure which shows the analysis result of FIG. It is a cross-sectional schematic diagram of the clad material which concerns on this invention. It is a cross-sectional schematic diagram of the clad material which concerns on this invention.

Hereinafter, preferred embodiments of the present invention will be described in detail.
[Embodiment 1]
In the SCR continuous casting and rolling apparatus according to the present embodiment, combustion is performed in a reducing atmosphere, and the base material is melted into a molten metal in a melting furnace having a reducing atmosphere by CO gas or the like. The molten metal is added and melted, and this molten metal is stored in a tundish, and a roughing material (diameter φ8 mm) is produced by a mold formed between the casting wheel and the endless belt through the nozzle. Then, it was processed to a diameter of 2.6 mm by cold drawing, and a diluted copper alloy material for clad was manufactured. Further, it can be similarly processed to a size of φ2.6 mm or less, a plate material, and a deformed material. Furthermore, it is effective to roll the roughing material into a square shape or an irregular shape, and it is also possible to produce a deformed material by conform extrusion molding of the cast material.

  Table 1 shows the oxygen concentration, S concentration, Ti concentration, semi-softening temperature, electrical conductivity, dispersed particle size, and overall evaluation of these materials of the present invention and the comparative material.

先ず、実験材として、表１に示した酸素濃度、硫黄濃度、Ｔｉ濃度で、φ８ｍｍｔの銅の荒引き材(ロッド):加工度９９.３％をそれぞれ作製した。φ８ｍｍの銅線は、ＳＣＲ連続鋳造圧延により、熱間圧延加工を施したものである。Ｔｉは、シャフト炉で溶解された銅溶湯を還元ガス雰囲気で樋に流し、樋に流した銅溶湯を同じ還元ガス雰囲気の鋳造ポットに導き、この鋳造ポットにて、Ｔｉを添加した後、これをノズルを通して鋳造輪と無端ベルトとの間に形成される鋳型にて鋳塊ロッドを作成した。この鋳塊ロッドを熱間圧延加工してφ８ｍｍの銅線を作成したものである。その実験材を冷間圧延して、φ２.６ｍｍのサイズにおける半軟化温度と導電率を測定し、またφ８ｍｍの銅材における分散粒子サイズを評価した。

First, as an experimental material, copper roughing material (rod) of φ8 mmt with the oxygen concentration, sulfur concentration, and Ti concentration shown in Table 1 was prepared. The φ8 mm copper wire is hot-rolled by SCR continuous casting and rolling. Ti flows the molten copper melted in the shaft furnace into the reed in the reducing gas atmosphere, guides the molten copper flowing in the reed to the casting pot of the same reducing gas atmosphere, and after adding Ti in this casting pot, An ingot rod was made with a mold formed between the cast ring and the endless belt through the nozzle. This ingot rod is hot-rolled to produce a φ8 mm copper wire. The experimental material was cold-rolled, the semi-softening temperature and conductivity at a size of φ2.6 mm were measured, and the dispersed particle size at a copper material of φ8 mm was evaluated.

  The oxygen concentration was measured with an oxygen analyzer (Leco ™ oxygen analyzer). Each concentration of sulfur and Ti is the result of analysis with an ICP emission spectroscopic analyzer.

  The measurement of the semi-softening temperature in the size of φ2.6 mm was obtained from the result of quenching in water after holding each temperature for 1 hour at 400 ° C. or less and conducting a tensile test. Semi-softening the temperature corresponding to the strength showing half the difference in tensile strength, using the result of tensile test at room temperature and the result of tensile test of soft copper heat-treated for 1 hour at 400 ° C. Determined as temperature.

It is desirable that the dispersed particles have a small size and are distributed a lot. The reason is that the size is small and the number is large because it functions as a sulfur deposition site. That is, the case where the number of dispersed particles having a diameter of 500 nm or less was 90% or more was regarded as acceptable. Here, the “size” is the size of the compound and means the size of the major axis of the major axis and minor axis of the shape of the compound. Further, “particles” refer to the TiO, TiO ₂ , TiS, and Ti—O—S. “90%” indicates the ratio of the number of corresponding particles to the total number of particles.

  The comparative material 1 is the result of trial production of a φ8 mm copper material in an Ar atmosphere in Table 1 in Table 1, and is obtained by adding 0 to 18 mass ppm of Ti to the molten copper.

  With the addition of Ti, the addition of 13 mass ppm decreases to 160 ° C. and becomes minimum with the addition of zero mass at a semi-softening temperature of 215 ° C., increases with the addition of 15, 18 mass ppm, and the desired softening temperature of 148 ° C. It did not become the following. However, although the industrially required electrical conductivity was 98% IACS or more and satisfied, the overall evaluation was x.

  Therefore, a comparative material 2 of φ8 mm copper material (rod) was manufactured by trial using the SCR continuous casting and rolling method and adjusting the oxygen concentration to 7 to 8 mass ppm.

  The comparative material 2 is one having a low Ti concentration (0, 2 mass ppm) among prototyping by the SCR continuous casting and rolling method, and the conductivity is 102% IACS or more, but the semi-softening temperature is 164 ° C, 157 ° C. Yes, because the required temperature of 148 ° C. or lower was not satisfied, the overall evaluation was x.

  The execution material 1 is the result of the prototype material in which the oxygen concentration and sulfur are substantially constant (7 to 8 mass ppm, 5 mass ppm) and the Ti concentration is different (4 to 55 mass ppm).

  When the Ti concentration is in the range of 4 to 55 mass ppm, the softening temperature is 148 ° C. or less, the conductivity is 98% IACS or more, 102% IACS or more, and the dispersed particle size is 500% or less of the particles of 90% or more. is there. And the surface of the rod is also clean, and both are satisfied as product performance (overall evaluation ○).

  Here, the case where the electrical conductivity satisfies 100% IACS or higher is when the Ti concentration is 4 to 37 mass ppm, and the case where the electrical conductivity satisfies 102% IACS or higher is when the Ti concentration is 4 to 25 mass ppm. When the Ti concentration was 13 mass ppm, the conductivity was 102% IACS, which was the maximum value, and the conductivity was slightly lower around this concentration. This is because when Ti is 13 mass ppm, the sulfur content in copper is captured as a compound, thereby exhibiting a conductivity close to that of high-purity copper (6N).

  Therefore, both the semi-softening temperature and the conductivity can be satisfied by increasing the oxygen concentration and adding Ti.

  Comparative material 3 is a prototype material having a Ti concentration as high as 60 mass ppm. In this comparative material 3, the electrical conductivity satisfies the request, but the semi-softening temperature is 148 ° C. or higher, and the product performance is not satisfied. Furthermore, there were many surface scratches on the rod, making it difficult to produce a product. Therefore, the addition amount of Ti is preferably less than 60 mass ppm.

  The implementation material 2 is a prototype material in which the sulfur concentration is set to 5 mass ppm, the Ti concentration is set to 13 to 10 mass ppm, and the oxygen concentration is changed to examine the influence of the oxygen concentration.

  With respect to the oxygen concentration, prototype materials having greatly different concentrations from 2 mass ppm to 30 mass ppm or less were used. However, when oxygen is less than 2 mass ppm, production is difficult and stable production cannot be performed, so the overall evaluation is Δ. It was also found that even when the oxygen concentration was increased to 30 mass ppm, both the semi-softening temperature and the conductivity were satisfied.

  As shown in the comparative material 4, when the oxygen was 40 mass ppm, there were many scratches on the rod surface, and the product was not a product.

  Therefore, by setting the oxygen concentration in the range of more than 2 mass ppm and less than 30 mass ppm, the characteristics of semi-softening temperature, electrical conductivity of 102% IACS or more, and dispersed particle size can be satisfied, and the surface of the rod is clean. Yes, both can satisfy product performance.

  The implementation material 3 is an example of a prototype material in which the oxygen concentration and the Ti concentration are relatively close to each other and the sulfur concentration is changed to 4 to 20 mass ppm. In this material 3, the prototype material with less than 2 mass ppm of sulfur could not be realized from the raw material side, but by satisfying both the semi-softening temperature and the conductivity by controlling the concentrations of Ti and sulfur. Can do.

  When the sulfur concentration of the comparative material 5 was 18 mass ppm and the Ti concentration was 13 mass ppm, the semi-softening temperature was high at 162 ° C. and the required characteristics could not be satisfied. Moreover, since the surface quality of the rod was particularly poor, it was difficult to produce a product.

  From the above, when the sulfur concentration is 2 to 12 mass ppm, the properties of semi-softening temperature, conductivity of 102% IACS or more, and dispersed particle size are satisfied, and the surface of the rod is clean and satisfies all product performance. I found out that

  Although the comparative material 6 showed the examination result using high purity copper (6N), it is a semi-softening temperature 127-130 degreeC, and electrical conductivity is 102.8% IACS, and dispersion particle size is also 500 micrometers or less. No particles were observed.

表２は、製造条件としての、溶融銅の温度及び圧延温度と半軟化温度、導電率、表面品質、分散粒子サイズ及び総合評価との関係を示したものである。

Table 2 shows the relationship between the molten copper temperature, rolling temperature, semi-softening temperature, electrical conductivity, surface quality, dispersed particle size, and comprehensive evaluation as manufacturing conditions.

  Comparative material 7 shows the result of trial production of a rod having a diameter of 8 mm at a molten metal temperature of 1330 to 1350 ° C. and a rolling temperature of 950 to 600 ° C.

  Although this comparative material 7 satisfies the semi-softening temperature and the electrical conductivity, some of the dispersed particles have a size of about 1000 nm, and the particles of 500 nm or more exceeded 10%. Therefore, this is unsuitable.

  The execution material 4 shows the result of trial manufacture of a rod of φ8 mm at 880 ° C. to 550 ° C. with a molten copper temperature of 1200 to 1320 ° C. and a low rolling temperature. With respect to this Example 4, the rod surface quality and the dispersed particle size were also good, and the overall evaluation was good.

  Comparative material 8 shows the result of trial manufacture of a rod of φ8 mm at 880 ° C. to 550 ° C. with a molten copper temperature of 1100 ° C. and a lower rolling temperature. Since this comparative material 8 had a low molten copper temperature, there were many surface scratches on the rod and it was not suitable for the product. This is because scratches are likely to occur during rolling because the molten copper temperature is low.

  Comparative material 9 shows the result of trial production of a rod of φ8 mm at 950 ° C. to 600 ° C. with a molten copper temperature of 1300 ° C. and a higher rolling temperature. Since this comparative material 9 has a high hot rolling temperature, the surface quality of the rod is good, but some of the dispersed particles are large, and the overall evaluation is x.

  Comparative material 10 shows the result of trial manufacture of a rod of φ8 mm at 880 ° C. to 550 ° C. with a molten copper temperature of 1350 ° C. and a lower rolling temperature. Since this comparative material 10 has a high molten copper temperature, some of the dispersed particles have a large size, and the overall evaluation is x.

表３は、ＳＣＲ連続鋳造圧延により、鋳造温度と圧延温度を変化させ、幅２００ｍｍ×厚さ８ｍｍの板材を作製したときの、製造条件としての、溶融銅の溶解温度及び圧延温度と半軟化温度、導電率、表面品質、分散粒子サイズ及び総合評価との関係を示したものである。半軟化温度及び導電率は、厚さ８ｍｍから０.８ｍｍまで冷間圧延したものを試料として評価した。

Table 3 shows the melting temperature, rolling temperature, and semi-softening temperature of molten copper as manufacturing conditions when the casting temperature and rolling temperature were changed by SCR continuous casting and rolling to produce a plate having a width of 200 mm and a thickness of 8 mm. , Conductivity, surface quality, dispersed particle size, and overall evaluation. The semi-softening temperature and electrical conductivity were evaluated using a sample that was cold-rolled from a thickness of 8 mm to 0.8 mm.

  The comparative material 11 shows the result of trial manufacture of a flat plate at a molten copper temperature of 1330 to 1350 ° C. and a rolling temperature of 950 to 600 ° C. Although this comparative material 11 satisfied the semi-softening temperature and the electrical conductivity, the size of the dispersed particles was about 1000 nm, and the particles of 500 nm or more exceeded 10%. Therefore, this comprehensive evaluation was x.

  The implementation material 5 shows the result of trial manufacture of a flat plate having a molten copper temperature of 1200 to 1320 ° C. and a lower rolling temperature of 880 to 550 ° C. and a width of 20 mm and a thickness of 1.0 mm. About this implementation material 5, the surface quality of the board | plate material and the dispersed particle size were also favorable, and the comprehensive evaluation was (circle).

  The comparative material 12 shows the result of trial manufacture of a flat plate having a molten copper temperature of 1100 ° C. and a lower rolling temperature of 880 ° C. to 550 ° C. and a width of 20 mm and a thickness of 1.0 mm. Since this comparative material 12 had a low molten copper temperature, there were many surface scratches on the plate material and it was not suitable for the product. This is because scratches are likely to occur during rolling because the molten copper temperature is low.

  The comparative material 13 shows the result of trial manufacture of a flat plate having a molten copper temperature of 1300 ° C. and a high rolling temperature of 950 ° C. to 600 ° C. and a width of 20 mm and a thickness of 1.0 mm. Since this comparative material 13 had a high hot rolling temperature, the surface quality of the plate material was good, but there were also large dispersed particle sizes, and the overall evaluation was x.

The comparative material 14 shows the result of trial manufacture of a flat plate having a molten copper temperature of 1350 ° C. and a rolling temperature of 880 ° C. to 550 ° C. and a width of 20 mm and a thickness of 1.0 mm. Since this comparative material 14 had a high molten copper temperature, some of the dispersed particles had a large size, and the overall evaluation was x.
[Embodiment 2]
FIG. 7 is a cross-sectional view showing the clad material of the present invention. In the clad material of the present invention, a layer made of aluminum or an aluminum alloy and a copper layer are combined and integrated. An example of the composite integration method is a cold rolling method. The Cu and Al clad material produced by cold rolling is rolled to a predetermined thickness according to the product, and then heat treated at 130 to 190 ° C. so that subsequent pressing, bending and deep drawing can be performed.

  The Cu layer of the clad material of the present invention is composed of the aforementioned diluted copper alloy material. Further, the clad material of the present invention is not limited to the two-layer structure, and the same effect can be obtained with a structure of three or more layers as shown in FIG.

  Furthermore, the clad material of the present invention is not limited to the combination of Cu and Al, and the same applies to metals and alloy materials such as Fe, ferrite, and austenitic stainless steel that form intermetallic compounds by heating in combination with Cu. The effect is obtained.

  The clad material according to the present invention has a heat treatment temperature or heating time for softening a material hardened by joining different metals to Cu and subsequent rolling in the production of a normal clad material by cold working. It can be greatly reduced. Therefore, the growth of brittle intermetallic compounds formed at the Cu and dissimilar metal interface is suppressed, and the cracking at the Cu / dissimilar metal interface, which significantly reduces the material strength, is suppressed. Workability can be remarkably improved.

  In addition, the present invention applies the diluted copper alloy material of the present invention in place of the conventional Cu, thereby achieving this characteristic, by adding a third expensive material or being complicated by the clad laminated structure There is no increase in material or manufacturing costs.

  The third material from the top of the implementation material 1 is obtained by obtaining a cast material having a molten copper temperature of 1320 ° C. and a hot rolling temperature of the first rolling roll temperature of 880 ° C. to the final rolling roll temperature of 550 ° C. and a thickness of 8 mm, Further, this was cold-rolled to obtain a copper alloy plate having a width of 200 mm and a thickness of 0.8 mm. This copper alloy strip and pure aluminum (thickness 0.8 mm) were combined and integrated by cold rolling. Further, the Cu and Al clad material was rolled to a thickness of 0.4 mm, and then heat-treated at 130 ° C. × 1 h.

  A copper alloy plate was obtained in the same manner as in Example 1, and this and pure aluminum (thickness 0.8 mm) were combined and integrated by cold rolling. Further, the Cu and Al clad material was rolled to a thickness of 0.4 mm, and then heat-treated at 190 ° C. × 1 h.

The upper and lower surfaces of aluminum (thickness 0.8 mm) were sandwiched between copper alloy strips (thickness 0.8 mm) obtained by the same method as in Example 1, and were combined and integrated by a pure cold rolling method. Further, the Cu, Al, and Cu clad material were rolled to a thickness of 0.4 mm, and then heat-treated at 190 ° C. × 1 h.
[Comparative Example 1]
A copper alloy strip (thickness 0.8 mm) obtained by the same method as in Example 1 and pure aluminum (thickness 0.8 mm) were combined and integrated by cold rolling. Further, the Cu and Al clad material was rolled to a thickness of 0.4, and then heat-treated at 120 ° C. × 1 h.
[Comparative Example 2]
A copper alloy strip (thickness 0.8 mm) obtained by the same method as in Example 1 and pure aluminum (thickness 0.8 mm) were combined and integrated by cold rolling. Further, the Cu and Al clad material was rolled to a thickness of 0.4 mm, followed by heat treatment at 200 ° C. × 1 h.
[Comparative Example 3]
A copper strip (thickness 0.8 mm) having a purity of 99.99% and pure aluminum (thickness 0.8 mm) were combined and integrated by cold rolling. Further, the Cu and Al clad material was rolled to a thickness of 0.4 mm, and then heat-treated at 130 ° C. × 1 h.
[Comparative Example 4]
A copper strip (thickness 0.8 mm) having a purity of 99.99% and pure aluminum (thickness 0.8 mm) were combined and integrated by cold rolling. Further, the Cu and Al clad material was rolled to a thickness of 0.4 mm, and then heat-treated at 190 ° C. for 1 h.
[Comparative Example 5]
A copper strip (thickness 0.8 mm) having a purity of 99.99% and pure aluminum (thickness 0.8 mm) were combined and integrated by cold rolling. Further, the Cu and Al clad material was rolled to a thickness of 0.4 mm, followed by heat treatment at 200 ° C. × 1 h.
[Conventional example 1]
One side of a 99.99% pure copper strip (thickness 0.8 mm) was subjected to Ni plating (10 μm) treatment, and pure aluminum (thickness 0.8 mm) was combined and integrated by cold rolling. Further, the Cu, Ni, and Al clad materials were rolled to a thickness of 0.4 mm, and then heat-treated at 130 ° C. × 1 h.
[Conventional example 2]
One side of a 99.99% pure copper strip (thickness 0.8 mm) was subjected to Ni plating (10 μm) treatment, and pure aluminum (thickness 0.8 mm) was combined and integrated by cold rolling. Further, the Cu, Ni, and Al clad materials were rolled to a thickness of 0.4 mm, and then heat-treated at 190 ° C. × 1 h.
[Conventional Example 3]
One side of a 99.99% pure copper strip (thickness 0.8 mm) was subjected to Ni plating (10 μm) treatment, and pure aluminum (thickness 0.8 mm) was combined and integrated by cold rolling. Further, the Cu, Ni, and Al clad materials were rolled to a thickness of 0.4 mm, and then heat-treated at 200 ° C. × 1 h.

表４は、実施例、比較例及び従来例のそれぞれのクラッド材について、加工性、経済性(材料コスト、製造コスト)を判定し、総合評価を行った結果を示すものである。加工性については、ＪＩＳ−Ｚ−２２４７に準じてエリクセン試験を実施し、エリクセン値が１０ｍｍ以上を合格(○）、７ｍｍ以上〜１０ｍｍ未満を可(△)、７ｍｍ未満を不可(×)とした。

Table 4 shows the results of comprehensive evaluation by determining workability and economy (material cost, manufacturing cost) for each of the clad materials of Examples, Comparative Examples, and Conventional Examples. For workability, an Erichsen test was conducted in accordance with JIS-Z-2247, and an Erichsen value of 10 mm or more was accepted (◯), 7 mm or more but less than 10 mm was acceptable (Δ), and less than 7 mm was unacceptable (x). .

  As shown in Table 4, Examples 1 to 3 according to the present invention could be evaluated as excellent characteristics in both processability and economy. In Comparative Example 1, work hardening due to rolling could not be sufficiently removed by the corresponding heat treatment, and the elongation of the material could not be obtained. On the other hand, in Comparative Example 2 where the heat treatment temperature was higher, formation of a brittle intermetallic compound at the interface between Cu and Al became the starting point of fracture, and good characteristics could not be obtained. Similarly to Comparative Example 1, Comparative Examples 3 and 4 did not obtain the elongation required for processing in the corresponding heat treatment. Conversely, Comparative Example 5 tried to obtain the elongation necessary for processing by increasing the heat treatment temperature. Then, as in Comparative Example 2, it was found that a brittle metal compound was formed at the Cu / Al interface, leading to early fracture.

  In the conventional example 1 and the conventional example 2, the workability was poor, but in the conventional example 3 in which the heat treatment temperature was further increased, the workability was improved. This is considered to be because the formation of an intermetallic compound of Cu and Al is suppressed in this structure. However, it is clear that the conventional examples 1 to 3 having a complicated layer structure increase the material cost and the manufacturing cost.

  From the above results, it was possible to evaluate that the clad materials excellent in workability and economy are Examples 1 to 3 according to the present invention. And it turned out that the cladding material of Cu and Al implemented by this examination shows the outstanding workability on the heat treatment conditions of temperature 130-190 degreeC and 1 h.

  In addition to the combination of Cu and Al of the clad materials of Examples 1 to 3, in combination with Cu, pure iron that forms an intermetallic compound by heating, SUS405 ferritic stainless steel, and SUS304 austenitic stainless steel A clad material can be obtained in the same manner as in Examples 1 to 3, and similar effects are also obtained.

  The Cu and Al clad materials of Examples 1 to 3 are particularly low in softening temperature and excellent in surface quality, so that they can be used for heat sinks used for cooling semiconductor devices, cases for electronic devices, battery cases, etc. It is applied and has an excellent effect.

  DESCRIPTION OF SYMBOLS 1 ... Copper layer, 2 ... Al layer, Al alloy layer, the metal layer which forms an intermetallic compound with Cu, or its alloy layer.

Claims (10)

In the clad material formed by joining dissimilar metal materials,
One of the dissimilar metal materials contains an additive element selected from the group consisting of Ti, Mg, Zr, Nb, Ca, V, Ni, Mn and Cr, and oxygen in an amount exceeding 2 mass ppm, with the balance being A clad material which is a dilute copper alloy material made of inevitable impurities and copper.   2. The clad material according to claim 1, wherein one of the different metal materials contains sulfur of 2 to 12 mass ppm, oxygen of 2 mass ppm to 30 mass ppm or less, and Ti of 4 to 55 mass ppm.   3. The clad material according to claim 1, wherein the diluted copper alloy material has a softening temperature of 0.8 mm and a temperature of 130 to 148 ° C. 3. In claim 1, said sulfur and Ti are mainly, _TiO, to form a TiO 2, compounds in the form of TiS and TiO-S or aggregates, and a small amount of the sulfur and Ti Is a solid solution in the diluted copper alloy material. 5. The particle diameter of the compound or aggregate according to claim 4, wherein the TiO is 200 nm or less, the TiO ₂ is 1000 nm or less, the TiS is 200 nm or less, and the Ti—O—S is 300 nm or less. A clad material characterized in that 90% or more of particles having a size of 500 nm or less are distributed in crystal grains.   6. The clad material according to claim 1, wherein the other metal material is pure Al.   Contains an additive element selected from the group consisting of Ti, Mg, Zr, Nb, Ca, V, Ni, Mn, and Cr and oxygen in an amount exceeding 2 mass ppm, with the remainder being an inevitable impurity and copper. A step of making a copper alloy material into a molten metal at a casting temperature of 1100 to 1320 ° C. by continuous casting and rolling, and a step of producing a dilute copper alloy plate by hot rolling and cold rolling the casting material And a method for producing a clad material, comprising: a step of joining the diluted copper alloy plate and the dissimilar metal plate; and a heat treatment step of applying a heat treatment after the joining.   8. The production of a clad material according to claim 7, wherein the hot rolling temperature is 880 ° C. or lower at the first rolling roll and 550 ° C. or higher at the final rolling roll. Method. The method for producing a clad material according to claim 7 or 8, wherein the heating temperature in the heat treatment step is 130 to 190 ° C and the heating time is 0.5 to 5 hours.   The method for producing a clad material according to any one of claims 7 to 9, wherein the dilute copper alloy plate contains 2 to 12 mass ppm of sulfur, 30 mass ppm or less exceeding 2 mass ppm of oxygen and 4 to 55 mass ppm of Ti. .

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