JP6534809B2 - Aluminum alloy wire, aluminum alloy stranded wire, coated electric wire, wire harness, and method of manufacturing aluminum alloy wire and aluminum alloy stranded wire - Google Patents

Description

  The present invention relates to an aluminum alloy wire used as a conductor of an electrical wiring body, an aluminum alloy stranded wire, a coated electric wire, a wire harness, a method of manufacturing an aluminum alloy wire, and a method of measuring an aluminum alloy wire. The present invention relates to an aluminum alloy wire material having high bending fatigue characteristics while securing high flexibility and conductivity even when used as an extremely thin wire having a diameter of 5 mm or less.

  Conventionally, a copper or copper alloy (for example, brass) terminal (for example, brass) on a wire including a conductor of copper or copper alloy as an electric wiring body of a mobile such as a car, train or aircraft, or an electric wiring of an industrial robot A member called a so-called wire harness equipped with a connector has been used. In recent years, the performance and functionality of automobiles have been rapidly advanced, and along with this, the number of electric devices and control devices to be mounted on a car increases, and they are used for these devices. The number of electrical wiring bodies tends to increase. On the other hand, in order to improve the fuel consumption of moving bodies such as automobiles for environmental protection, weight reduction of moving bodies is strongly desired.

As one of the means for achieving such weight reduction of the movable body, for example, the conductor of the electric wiring body is considered to be a lighter weight aluminum or aluminum alloy instead of the conventionally used copper or copper alloy. It is in progress. The specific gravity of aluminum is about 1/3 of the specific gravity of copper, and the conductivity of aluminum is about 2/3 of the conductivity of copper (based on 100% IACS for pure copper, about 66% IACS for pure aluminum), Although it is necessary to increase the cross-sectional area of the aluminum conductor wire to about 1.5 times the cross-sectional area of the copper conductor wire in order to flow the same current as the copper conductor wire to the aluminum conductor wire, Even if a conductor wire of aluminum having a large cross-sectional area is used, the weight of the conductor wire of aluminum is about half of the mass of the conductor wire of pure copper. It is advantageous from the viewpoint of The above% IACS represents the conductivity when the resistivity of the international annealed copper standard (International Annealed Copper Standard) is 1.7241 × 10 ⁻⁸ Ωm as 100% IACS.

  However, it is known that, in a pure aluminum wire represented by an aluminum alloy wire for power transmission line (A1060 or A1070 according to JIS), generally, the tensile strength, the impact resistance, the bending fatigue property and the like are inferior. Therefore, for example, a load which is unexpectedly applied by a worker or an industrial device at the time of attaching to a vehicle body, a tension at a crimped portion at a connecting portion of an electric wire and a terminal, a bending which is loaded at a bent portion such as a door I can not stand fatigue etc. Moreover, although it is possible to increase tensile strength and flexural fatigue properties of materials alloyed by adding various additive elements, it is possible to cause a decrease in conductivity due to the solid solution phenomenon of the additive elements in aluminum, and to make it hard As a result, there is a problem that the handling property is reduced at the time of attaching the wire harness and the productivity is reduced. Therefore, it has been necessary to limit or select the additive element within the range in which the conductivity is not reduced, and to further achieve both bending fatigue resistance and flexibility.

  Further, as a high-strength aluminum alloy wire, for example, an aluminum alloy wire containing Mg and Si is known, and as a typical example of this aluminum alloy wire, a 6000 series aluminum alloy (Al-Mg-Si alloy) wire Can be mentioned. In general, the 6000 series aluminum alloy wire can be strengthened by performing solution treatment and aging treatment. However, when manufacturing extremely thin wires with a wire diameter of 0.5 mm or less using 6000 series aluminum alloy wire rod, although high conductivity and high bending fatigue characteristics can be achieved by solution treatment and aging treatment, the yield strength (0 (0) .2% proof stress), plastic deformation requires a large force, and installation efficiency to the vehicle body tends to decrease.

  As a conventional 6000 series aluminum alloy wire used for an electrical wiring body of a mobile, it is indicated, for example in patent documents 1. Patent Document 1 is a patent application based on the results of research and development by the inventors, which defines the size of the average crystal grain size in the outer peripheral portion of the wire and in the inside, and is equal to or more than the conventional product. In addition to maintaining the extensibility and conductivity of the steel, it is a combination of an appropriate proof stress and a high bending fatigue resistance.

Patent No. 5607853

However, depending on the application of the aluminum alloy wire, there may be a need for further improvement of the bending fatigue characteristics, and a further technical improvement is required.
Moreover, even if it is an aluminum alloy wire material which has a characteristic equivalent to patent document 1, the technical improvement which can aim at ensuring of mass productivity by shortening of a manufacturing process time is calculated | required.
The object of the present invention is to ensure that even when used as an ultrafine wire having a wire diameter of 0.5 mm or less, while maintaining high tensile strength and high conductivity, bending fatigue properties are higher than before, 0. Abstract: Providing an aluminum alloy wire rod, an aluminum alloy stranded wire, a coated electric wire, and a wire harness used as a conductor of an electrical wiring body having a suitably low 2% proof stress and excellent mass productivity, and an aluminum alloy wire rod and an aluminum alloy twisted wire It is to provide a manufacturing method of

  The present inventors clarified the influence which the addition component and the manufacturing process have on the alloy structure, using the precipitation type Al-Mg-Si alloy which can obtain high strength and high conductivity which have been studied so far, We succeeded in precipitating the MgSi compound preferentially on the outer periphery. Based on this research result, when the aluminum alloy wire is bent and deformed, the MgSi compound is preferentially precipitated in a short time at the outer peripheral portion to which the largest stress is applied, and the outer peripheral portion is reinforced to improve the bending fatigue characteristics. It is found that the aluminum alloy wire rod according to the present invention can be improved compared to the prior art, and that the 0.2% proof stress can be kept appropriately low inside the wire rod, and furthermore, an aluminum alloy wire rod having both high tensile strength and high conductivity can be obtained. It came to complete.

That is, the gist configuration of the present invention is as follows.
(1) Mg: 0.1 to 1.0% by mass, Si: 0.1 to 1.2% by mass, Fe: 0.01 to 1.40% by mass, Ti: 0 to 0.100% by mass, B : 0 to 0.030 mass%, Cu: 0 to 1.00 mass%, Ag: 0 to 0.50 mass%, Au: 0 to 0.50 mass%, Mn: 0 to 1.00 mass%, Cr : 0 to 1.00 mass%, Zr: 0 to 0.50 mass%, Hf: 0 to 0.50 mass%, V: 0 to 0.50 mass%, Sc: 0 to 0.50 mass%, Co : 0 to 0.50 mass%, Ni: 0 to 0.50 mass%, balance: Al and unavoidable impurities
Aluminum characterized in that the number N _out of precipitates having a diameter of 1 μm or less containing Mg and / or Si at the outer peripheral portion is larger than the number N _in of precipitates having a diameter of 1 μm or less containing Mg and / or Si inside Alloy wire rod.
(2) The Vickers hardness of the outer peripheral portion is 60 to 130 Hv, the Vickers hardness of the inner portion is 50 to 120 Hv, and the ratio of the Vickers hardness of the outer peripheral portion to the Vickers hardness of the inner portion is greater than 1.0 1) The aluminum alloy wire rod as described above.
(3) The above (1), wherein the chemical composition contains one or two selected from the group consisting of Ti: 0.001 to 0.100% by mass and B: 0.001 to 0.030% by mass. ) Aluminum alloy wire rod described.
(4) The chemical composition is Cu: 0.01 to 1.00% by mass, Ag: 0.01 to 0.50% by mass, Au: 0.01 to 0.50% by mass, Mn: 0.01 to 50% 1.00 mass%, Cr: 0.01 to 1.00 mass%, Zr: 0.01 to 0.50 mass%, Hf: 0.01 to 0.50 mass%, V: 0.01 to 0. One or two selected from the group consisting of 50% by mass, Sc: 0.01 to 0.50% by mass, Co: 0.01 to 0.50% by mass and Ni: 0.01 to 0.50% by mass The aluminum alloy wire rod according to any one of the above (1) to (3), containing a species or more.
(5) The aluminum alloy wire rod according to any one of the above (1) to (4), wherein the chemical composition contains Ni: 0.01 to 0.50 mass%.
(6) In the above ((1), the total content of Fe, Ti, B, Cu, Ag, Au, Mn, Cr, Zr, Hf, V, Sc, Co, Ni is 0.01 to 2.00% by mass) The aluminum alloy wire rod in any one of 1)-(5).
(7) The aluminum alloy wire according to any one of the above (1) to (6), which is an aluminum alloy wire having a wire diameter of 0.1 to 0.5 mm.
(8) Mg: 0.1 to 1.0% by mass, Si: 0.1 to 1.2% by mass, Fe: 0.01 to 1.40% by mass, Ti: 0 to 0.100% by mass, B : 0 to 0.030 mass%, Cu: 0 to 1.00 mass%, Ag: 0 to 0.50 mass%, Au: 0 to 0.50 mass%, Mn: 0 to 1.00 mass%, Cr : 0 to 1.00 mass%, Zr: 0 to 0.50 mass%, Hf: 0 to 0.50 mass%, V: 0 to 0.50 mass%, Sc: 0 to 0.50 mass%, Co An aluminum alloy twisted wire constituted by twisting a plurality of aluminum alloy wire rods consisting of: 0 to 0.50 mass%, Ni: 0 to 0.50 mass%, balance: Al and unavoidable impurities,
Aluminum characterized in that the number N _out of precipitates having a diameter of 1 μm or less containing Mg and / or Si at the outer peripheral portion is larger than the number N _in of precipitates having a diameter of 1 μm or less containing Mg and / or Si inside Alloy stranded wire.
(9) A coated electric wire having a coating layer on the outer periphery of the aluminum alloy wire rod according to the above (1) or the aluminum alloy stranded wire according to the above (8).
(10) A wire harness comprising the coated electric wire according to the above (9) and a terminal of the coated electric wire attached to the end of the coated electric wire from which the cover layer has been removed.
(11) A method of manufacturing an aluminum alloy wire rod, which is subjected to hot working after melting and casting to form a rough drawn wire, and then at least each step of wire drawing, solution heat treatment, strain introduction treatment and aging heat treatment ,
The solution heat treatment is heated to a predetermined temperature within the range of 450 to 580 ° C., and then cooled to a temperature of at least 150 ° C. at an average cooling rate of 10 ° C./s or more,
The strain introduction process introduces strain to the outer peripheral portion of the wire after the solution heat treatment and before the aging heat treatment,
The said aging heat treatment heats at predetermined | prescribed temperature within the range of 20-250 degreeC, The manufacturing method of the aluminum alloy wire in any one of said (1)-(7) characterized by the above-mentioned.
(12) The method for producing an aluminum alloy wire according to (11), wherein the strain introducing process introduces strain to an outer peripheral portion of the wire by bending the wire.
(13) In the strain introducing process, the drawing process in which the working ratio per pass is 10% or less is performed one or more times, and the strain is introduced to the outer peripheral portion of the wire at a total working ratio of 10% or less 11) The manufacturing method of the aluminum alloy wire rod as described.
(14) After melting and casting, form a rough drawn wire through hot working, and then perform at least the steps of wire drawing, solution heat treatment, strain introduction treatment, and aging heat treatment sequentially, and further twist wire processing of wire rod A method for producing an aluminum alloy stranded wire, which is performed after the wire drawing and before the aging heat treatment,
The solution heat treatment is heated to a predetermined temperature in the range of 450 to 580 ° C., and then cooled to a temperature of at least 150 ° C. at an average cooling rate of 10 ° C./s or more. Introduce strain into the outer periphery of the wire or stranded wire after wire processing and before the aging heat treatment,
The said aging heat treatment heats to predetermined | prescribed temperature within the range of 20-250 degreeC, The manufacturing method of the aluminum alloy twisted wire as described in said (8) characterized by the above-mentioned.
(15) The method for producing an aluminum alloy stranded wire according to the above (14), wherein the strain introducing process introduces strain to an outer peripheral portion of the wire or the stranded wire by bending the wire.
(16) In the strain introduction process, drawing is performed one or more times at a processing rate of 10% or less per pass, and strain is introduced to the outer peripheral portion of the wire or stranded wire at a total processing rate of 10% or less The manufacturing method of the aluminum alloy twisted wire as described in said (14).
In addition, among the elements whose content ranges are listed in the above-mentioned chemical composition, any element whose lower limit value of the content range is described as “0 mass%” is an optional additional element optionally added as needed Means That is, when the predetermined additive element is “0 mass%”, it means that the additive element is not contained.

  The aluminum alloy wire rod according to the present invention is reinforced so as to be applicable to small diameter wires, and is flexible, easy to handle, light in weight, and has high bending fatigue characteristics. Therefore, a battery cable, a harness or a motor mounted on a moving body It is useful as a wire for wiring, and a wiring body of an industrial robot. Moreover, according to the manufacturing method of the present invention, an aluminum alloy wire having excellent bending fatigue characteristics can be manufactured in a short time, and mass productivity is excellent.

It is a figure explaining the method of introduce | transducing distortion into the outer peripheral part of the aluminum alloy wire material which concerns on embodiment of this invention, (a) and (b) is 1st distortion introduction process, (c) is 2nd distortion formation Indicates processing. BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing explaining the outer peripheral part and the inside of the aluminum alloy wire material which concerns on embodiment of this invention, and aluminum alloy twisted wire, (a) shows an aluminum alloy wire, (b) shows aluminum alloy twisted wire. (A)-(c) is a figure explaining the method to measure the Vickers hardness of the outer peripheral part and the inside in the aluminum alloy wire rod of Fig.2 (a). It is a figure explaining the method to measure the Vickers hardness of the outer peripheral part and the inside in the aluminum alloy wire rod of FIG.2 (b).

The reasons for limitation of the chemical composition etc. of the present invention will be shown below.
(1) Chemical composition <Mg: 0.10 to 1.00 mass%>
Mg (magnesium) has the effect of solid solution strengthening in the aluminum matrix, and a part thereof precipitates together with Si as a β ′ ′ phase (beta double prime phase) etc. and has tensile strength and bending fatigue resistance In addition, it is an element having the effect of improving tensile strength and elongation when Mg-Si clusters are formed as solute atom clusters, however, if the Mg content is less than 0.10 mass%. When the Mg content is more than 1.00% by mass, the possibility of forming a Mg-concentrated portion in the grain boundaries is increased, and the tensile strength and the elongation are lowered. The yield strength is increased and the winding performance is reduced, and the conductivity is also reduced by increasing the solid solution amount of the Mg element, therefore, the Mg content is 0.10 to 1.00 mass%. The Mg content is preferably 0.50 to 1.00% by mass in the case of placing importance on high strength, and 0.10 to 0.50 mass in the case of placing importance on conductivity. It is preferable to set it as%, and 0.30 to 0.70 mass% is generally preferable from such a viewpoint.

<Si: 0.10 to 1.20 mass%>
Si (silicon) has the action of solid solution in the aluminum matrix to strengthen it, and a part of it is precipitated together with Mg as a β ′ ′ phase etc. and has the action of improving the tensile strength and bending fatigue resistance properties In addition, Si is an element having an effect of improving tensile strength and elongation when Mg-Si clusters or Si-Si clusters are formed as solute atomic clusters, if the Si content is less than 0.10 mass% When the above-described effects and effects are insufficient and the Si content exceeds 1.00 mass%, the possibility of forming a Si-enriched portion in the crystal grain boundaries is increased, and the tensile strength and the elongation decrease, and the proof stress In addition, the conductivity decreases as the solid solution amount of Si element increases, so the Si content is 0.10 to 1.20% by mass. The amount is preferably 0.50 to 1.00% by mass when importance is given to high strength, and preferably 0.10 to 0.50% by mass when importance is attached to conductivity From such a point of view, 0.30 to 0.70 mass% is preferable as a whole.

<Fe: 0.01 to 1.40% by mass>
Fe (iron) is an element that contributes to the refinement of crystal grains by mainly forming an Al—Fe-based intermetallic compound and improves the tensile strength. Fe can only form a solid solution of 0.05 mass% in Al at 655 ° C. and is less at room temperature, so the remaining Fe that can not form a solid solution in Al is Al-Fe, Al-Fe-Si, Al-Fe Crystallized or precipitated as an intermetallic compound such as -Si-Mg. This intermetallic compound contributes to the refinement of the crystal grains and improves the tensile strength and the bending fatigue resistance. Further, Fe also has an effect of improving tensile strength and bending fatigue resistance by Fe dissolved in Al. If the Fe content is less than 0.01% by mass, these effects are insufficient, and if the Fe content is more than 1.40% by mass, wire drawing occurs due to coarsening of crystallized matter or precipitate. As the processability decreases, the yield strength increases and the manageability decreases. In addition, resistance to bending fatigue and conductivity also decrease. Therefore, the Fe content is 0.01 to 1.40% by mass, preferably 0.15 to 0.70% by mass, and more preferably 0.15 to 0.45% by mass.

  As described above, the aluminum alloy wire rod according to the present invention contains Mg, Si and Fe as essential components, but if necessary, it may further be one or two selected from the group consisting of Ti and B, Cu And one or more of Ag, Au, Mn, Cr, Zr, Hf, V, Sc, Co and Ni can be contained.

<Ti: 0.001 to 0.100% by mass>
Ti is an element having the function of refining the structure of the ingot during melt casting. If the structure of the ingot is coarse, disconnection occurs in the ingot cracking in the casting and in the wire processing step, which is not desirable industrially. If the Ti content is less than 0.001% by mass, the above-mentioned effects can not be sufficiently exhibited, and if the Ti content exceeds 0.100% by mass, the conductivity tends to decrease. It is. Therefore, the Ti content is 0.001 to 0.100 mass%, preferably 0.005 to 0.050 mass%, and more preferably 0.005 to 0.030 mass%.

<B: 0.001 to 0.030% by mass>
B, like Ti, is an element having the function of refining the structure of the ingot during melt casting. If the structure of the ingot is coarse, it is industrially undesirable because breakage tends to occur in the ingot cracking and wire rod processing steps during casting. If the B content is less than 0.001% by mass, the above-described effects can not be sufficiently exhibited, and if the B content exceeds 0.030% by mass, the conductivity tends to decrease. Therefore, the B content is 0.001 to 0.030 mass%, preferably 0.001 to 0.020 mass%, and more preferably 0.001 to 0.010 mass%.

<Cu: 0.01 to 1.00% by mass>, <Ag: 0.01 to 0.50% by mass>, <Au: 0.01 to 0.50% by mass>, <Mn: 0.01 to 1 .00 mass%>, <Cr: 0.01 to 1.00 mass%> and <Zr: 0.01 to 0.50 mass%>, <Hf: 0.01 to 0.50 mass%>, <V : 0.01 to 0.50 mass%>, <Sc: 0.01 to 0.50 mass%>, <Co: 0.01 to 0.50 mass%><Ni: 0.01 to 0.50 mass Containing one or more of%, Cu, Ag, Au, Mn, Cr, Zr, Hf, V, Sc, Co, and Ni all have the effect of refining crystal grains and abnormal coarse growth It is an element which suppresses the formation of grains, and further, Cu, Ag and Au are elements which also have the effect of enhancing grain boundary strength by precipitating in grain boundaries. If at least one of these elements is contained in an amount of 0.01% by mass or more, the above-described effects can be obtained, and tensile strength and elongation can be improved. On the other hand, when any of the contents of Cu, Ag, Au, Mn, Cr, Zr, Hf, V, Sc, Co and Ni exceeds the above upper limit, the compound containing the element becomes coarse. In order to deteriorate the drawability, wire breakage tends to occur, and the conductivity tends to decrease. Therefore, the ranges of the contents of Cu, Ag, Au, Mn, Cr, Zr, Hf, V, Sc, Co and Ni were set to the above ranges, respectively. In addition, it is preferable to contain especially Ni in this element group. When Ni is contained, the grain refining effect and the abnormal grain growth suppressing effect become remarkable, and the tensile strength and the elongation are improved. In addition, the decrease in conductivity and the disconnection during wire drawing can be more easily suppressed. Since this effect becomes remarkable, the content of Ni is more preferably 0.05 to 0.3% by mass.

  In addition, as the content of Fe, Ti, B, Cu, Ag, Au, Mn, Cr, Zr, Hf, V, Sc, Co and Ni increases, the conductivity tends to decrease and the wire drawability tends to deteriorate. There is a tendency for the handling property to decrease due to the increase in resistance. Therefore, the total content of these elements is preferably 2.00% by mass or less. Since Fe is an essential element in the aluminum alloy wire rod of the present invention, the total content of Fe, Ti, B, Cu, Ag, Au, Mn, Cr, Zr, Hf, V, Sc, Co and Ni is 0.01 It is 2.00 mass%. The content of these elements is more preferably 0.10 to 2.00% by mass. However, when these elements are added alone, the compound containing the element tends to be coarser as the content is larger, and the wire drawability is deteriorated and the wire tends to be broken. It was set as the content range of said prescription | regulation in an element.

  In order to lower the resistance value appropriately while maintaining high conductivity, the contents of Fe, Ti, B, Cu, Ag, Au, Mn, Cr, Zr, Hf, V, Sc, Co and Ni The total amount is particularly preferably 0.01 to 0.80% by mass, and more preferably 0.05 to 0.60% by mass. On the other hand, the conductivity slightly decreases, but in order to appropriately reduce the tensile strength, the elongation, and the proof stress value against the tensile strength, more than 0.80 to 2.00% by mass is particularly preferable, and 1.00 to 2. 00 mass% is more preferred.

<Remainder: Al and unavoidable impurities>
The balance other than the components described above is Al (aluminum) and unavoidable impurities. Unavoidable impurities here mean impurities of a content level that can be included inevitably in the manufacturing process. Since the unavoidable impurities can also be a factor to reduce the conductivity depending on the content, it is preferable to suppress the content of the unavoidable impurities to some extent in consideration of the decrease in the conductivity. As a component mentioned as an unavoidable impurity, Ga, Zn, Bi, Pb etc. are mentioned, for example.

Such an aluminum alloy wire can be realized by combining and controlling the alloy composition and the manufacturing process. Hereinafter, the suitable manufacturing method of the aluminum alloy wire rod of this invention is demonstrated.
(2) Manufacturing method of aluminum alloy wire rod of the present invention The aluminum alloy wire rod of the present invention is [1] melting, [2] casting, [3] hot working (groove rolling etc.), [4] first wire drawing Processing, [5] first heat treatment (intermediate heat treatment), [6] second wire drawing, [7] second heat treatment (solution heat treatment), [8] outer peripheral portion strain introduction treatment, and [9] third heat treatment It can manufacture by the manufacturing method including performing each process of (aging heat treatment) one by one. Before and after the second heat treatment, or after the aging heat treatment, a step of forming a stranded wire or a step of resin-coating a wire may be provided. The steps [1] to [9] will be described below.

[1] Melting Melting is carried out by adjusting the amount of each component so as to obtain the above-described aluminum alloy composition.

[2] Casting and [3] hot working (groove rolling etc.)
Then, using a properch type continuous casting and rolling machine combining casting wheels and a belt, the molten metal is cast with a water-cooled mold and continuously rolled, for example, a rod material having a diameter of 5 to 13 mm in diameter and a suitable thickness. Do. The cooling rate at the time of casting at this time is preferably 1 to 20 ° C./s from the viewpoint of preventing coarsening of the Fe-based crystallized product and prevention of conductivity decrease due to forced solid solution of Fe. It is not limited. Casting and hot rolling may be performed by billet casting and extrusion methods and the like.

[4] First wire drawing Next, peeling of the surface is carried out to make a bar with a diameter of, for example, 5 to 12.5 mmφ, which is then cold drawn. The processing degree η is preferably in the range of 1 to 6. Here, when the wire cross-sectional area before wire drawing is A ₀ and the wire cross-sectional area after wire drawing is A ₁ , the working degree η is represented by η = ln (A ₀ / A ₁ ). If the degree of processing η is less than 1, the recrystallized grains become coarse during the heat treatment of the next step, and the tensile strength and the elongation significantly decrease, which may cause disconnection. If the degree of processing 度 is more than 6, wire drawing becomes difficult, and problems may occur in terms of quality such as breakage during wire drawing. Peeling of the surface may, but does not have to, clean the surface.

[5] First heat treatment (intermediate heat treatment)
Next, a first heat treatment is performed on the cold drawn material to be processed. The first heat treatment of the present invention is performed in order to recover the flexibility of the workpiece and to improve the drawability. The first heat treatment may not be performed if the wire drawing processability is sufficient and no disconnection occurs.

[6] Second wire drawing processing After the first heat treatment, wire drawing processing is further performed cold. The processing degree η at this time is preferably in the range of 1 to 6. The degree of processing η affects the formation and growth of recrystallized grains. When the processing degree η is smaller than 1, the recrystallized grains tend to be coarsened, and the tensile strength and the elongation tend to be significantly reduced during the heat treatment of the next step, and when the processing degree η is larger than 6, wire drawing This is because it tends to cause problems in terms of quality such as breakage during wire drawing. When the first heat treatment is not performed, the first wire drawing and the second wire drawing may be performed continuously.

[7] Second heat treatment (solution heat treatment)
A second heat treatment is performed on the drawn material. The second heat treatment of the present invention is a solution heat treatment which is carried out to dissolve the compound of Mg and Si contained at random into the aluminum matrix. The solution treatment can smooth out (homogenize) the concentrated portions of Mg and Si during processing, and leads to suppression of grain boundary segregation of the compound of Mg and Si after final aging heat treatment. Specifically, the second heat treatment is heating to a predetermined temperature in the range of 450 to 580 ° C., and after holding for a predetermined time, cooled to at least a temperature of 150 ° C. at an average cooling rate of 10 ° C./s or more It is. When the predetermined temperature at the time of heating in the second heat treatment is higher than 580 ° C., the crystal grain size becomes coarse and abnormally grown grains are formed, and when the predetermined temperature is lower than 450 ° C., Mg ₂ Si is sufficiently dissolved I can not do it. Therefore, although the predetermined temperature at the time of heating in the second heat treatment changes depending on the contents of Mg and Si, it is in the range of 450 to 580 ° C., preferably 480 to 520 ° C.

  As a method of performing the second heat treatment, for example, batch heat treatment, a salt bath (salt bath), or continuous heat treatment such as high frequency heating, electric current heating, and inter-run heating may be used.

  However, when high frequency heating or electric current heating is used, the temperature of the wire rises with the passage of time because the current is normally supplied to the wire. Therefore, if the current continues to flow, the wire may be melted, so it is necessary to perform the heat treatment in an appropriate time range. Even in the case of using inter-heating, since the annealing is performed for a short time, the temperature of the inter-heating annealing furnace is usually set higher than the wire temperature. In the heat treatment for a long time, since the wire may be melted, it is necessary to carry out the heat treatment in an appropriate time range. Further, in all heat treatments, it is necessary to have a predetermined time or more for dissolving Mg and Si compounds randomly contained in the workpiece into the aluminum matrix. The heat treatment according to each method will be described below.

  The continuous heat treatment by high frequency heating is a heat treatment by Joule heat generated from the wire itself by the induction current when the wire continuously passes through the magnetic field by high frequency. The wire can be heat treated by controlling the temperature of the wire and the heat treatment time including the rapid heating and quenching steps. Cooling is performed by passing the wire continuously through water or nitrogen gas atmosphere after rapid heating. The heat treatment time is 0.01 to 2 s, preferably 0.05 to 1 s, more preferably 0.05 to 0.5 s.

  In the continuous current heat treatment, heat treatment is performed by Joule heat generated from the wire itself by passing an electric current through the wire continuously passing through the two electrode wheels. The wire can be heat treated by controlling the temperature of the wire and the heat treatment time including the rapid heating and quenching steps. Cooling is performed by passing the wire continuously through water, air, or a nitrogen gas atmosphere after rapid heating. The heat treatment time is 0.01 to 2 s, preferably 0.05 to 1 s, more preferably 0.05 to 0.5 s.

  During the continuous running heat treatment, the wire is continuously passed through the heat treatment furnace maintained at a high temperature for heat treatment. The wire material can be heat treated by controlling the temperature in the heat treatment furnace and the heat treatment time including the rapid heating and quenching steps. Cooling is performed by passing the wire continuously through water, air, or a nitrogen gas atmosphere after rapid heating. The heat treatment time is preferably 0.5 to 30 seconds.

When one or both of the wire temperature and the heat treatment time are lower than the conditions defined above, the solution atomization becomes incomplete and the solute atomic cluster, the β "phase and the Mg ₂ Si precipitate formed during the aging heat treatment in the subsequent step Decrease in tensile strength, impact resistance, resistance to bending fatigue, and improvement in conductivity Decreases grain size when one or both of wire temperature and annealing time are higher than the conditions specified above At the same time, partial melting (eutectic melting) of the compound phase in the aluminum alloy wire occurs, tensile strength and elongation decrease, and breakage easily occurs during handling of the conductor.

[8] Outer peripheral part distortion introduction processing A distortion introduction processing is performed to the outer peripheral part of the wire which performed the solution treatment. This strain introduction process is a process performed between the solution treatment and the aging heat treatment. This treatment is performed for the purpose of introducing a strain of 1 to 10% to the outer peripheral portion of the wire and promoting the precipitation of the Mg, Si compound or solute atomic cluster at the outer peripheral portion during the aging treatment described later. If the strain at the outer peripheral portion is less than 1%, high bending fatigue characteristics can not be obtained, and if it exceeds 10%, 0.2% proof stress becomes excessive.

For example, as shown in FIGS. 1 (a) and 1 (b), this outer peripheral portion strain introduction can be carried out by pressing the aluminum alloy wire 1 against the outer surface 10a of the jig 10 to perform bending. Specifically, a strain of 1% is introduced to the outer peripheral portion in the bending process using a round bar type jig with a diameter of 30 mm and a strain of 10% in a bending process using a round bar type jig with a diameter of 3 mm. The strain ε as the following equation (1) is multiplied by 100 to a value obtained by dividing the difference between the length l ₀ of the undeformed length l after deformation length l ₀ before deformation.
ε = (l−l ₀ ) / l ₀ * 100 (1)
Further, as shown in FIG. 1C, the outer peripheral portion can also be strained by passing the aluminum alloy wire 1 ′ through the hole 20a of the die 20. Specifically, drawing is performed one or more times using a die having a processing rate of 10% or less per pass, and strain is preferentially introduced to the outer peripheral portion at a total processing rate of 10% or less.

[9] Third heat treatment (aging heat treatment)
Then, a third heat treatment is performed. This third heat treatment is an aging heat treatment performed to form Mg, Si compounds or solute atom clusters. The aging heat treatment is preferably performed at a predetermined temperature in the range of 20 to 250 ° C. If the heating temperature in the aging heat treatment is less than 20 ° C., the formation of solute atom clusters is slow and it takes time to obtain the necessary tensile strength and elongation, which is disadvantageous in mass production. When the heating temperature is higher than 250 ° C., coarse Mg ₂ Si precipitates are formed and strength is lowered in addition to the Mg ₂ Si needle-like precipitates (β ′ ′ phase) most contributing to the strength. The heating temperature in the heat treatment is preferably 20 to 70 ° C. in order to form solute atom clusters more effective in improving elongation. The β ′ ′ phase is also precipitated simultaneously, and a balance between tensile strength and 0.2% proof stress is obtained. 100 to 150 ° C. is more preferable for taking.

  In the present embodiment, as described above, the strain introduction treatment is performed on the outer peripheral portion before the third heat treatment (aging heat treatment), so that the Mg, Si compound and / or solute atomic cluster in the outer peripheral portion during the main aging heat treatment. Precipitation is promoted, and the aging time until securing a desired amount of precipitation can be significantly shortened.

  The wire diameter of the aluminum alloy wire of this embodiment is not particularly limited and can be appropriately determined depending on the application, but in the case of a small diameter wire, 0.1 to 0.5 mmφ, in the case of a medium small diameter wire 0.8 to 1.5 mmφ is preferable. The aluminum alloy wire of the present embodiment is advantageous in that it can be used as an aluminum alloy wire by narrowing it with a single wire, but it is an aluminum alloy stranded wire obtained by bundling a plurality of strands and twisting them together, or an aluminum alloy compressed stranded wire It can also be used as In this case, among the steps [1] to [9] of the production method of the present invention, the aluminum alloy wire rod obtained by sequentially performing each step of [1] to [7] is bundled into a plurality of strands and twisted together An aluminum alloy stranded wire or an aluminum alloy compressed stranded wire may be produced, and after the twisting step, a [8] outer peripheral portion strain introduction step may be performed, and then a [9] aging heat treatment step may be performed (intermediate annealing → elongation Wire → solution treatment → strain introduction → (twisted wire) → aging → (coating)). Further, among the steps of [1] to [9], the aluminum alloy wire rod obtained by sequentially performing each of the steps [1] to [6] is bundled into a plurality of strands and twisted to form an aluminum alloy stranded wire or aluminum An alloy compression stranded wire may be prepared, and after the twisting step, [7] solution treatment may be performed, and thereafter, [8] outer peripheral portion strain introduction step and [9] aging heat treatment step may be sequentially performed (intermediate annealing → Wire drawing → stranded wire → solutionizing → strain introduction → aging → (coating)). By these manufacturing methods, distortion can be introduced also to the aluminum stranded wire or the aluminum alloy compression alloy stranded wire.

  Further, in the present embodiment, as an additional step, it is possible to carry out a homogenizing heat treatment as performed in the conventional method after continuous casting and rolling. Since the homogenization heat treatment can disperse the additive elements uniformly, it becomes easy to form solute atom clusters and β ′ ′ precipitate phase uniformly in the crystallized matter and the subsequent third heat treatment, and tensile strength and bending fatigue resistance The homogenization heat treatment is preferably performed at a heating temperature of 450 ° C. to 600 ° C., more preferably 500 ° C. to 600 ° C. In cooling in the homogenization heat treatment, Slow cooling at an average cooling rate of 0.1 to 10 ° C./min is preferable in that uniform compounds can be easily obtained.

(3) Structural characteristics of the aluminum alloy wire rod and the aluminum alloy stranded wire according to the present embodiment The aluminum alloy wire rod of the present embodiment manufactured by the above manufacturing method is included in a predetermined volume at the outer peripheral portion When the number of precipitates having a diameter of 1 μm or less containing Mg and / or Si is N _out and the number of precipitates having a diameter of 1 μm or less containing Mg and / or Si contained in the same volume inside is N _in It is characterized in that the number N _out of precipitates at N is greater than the number M _in of precipitates internally. For example, the number M _out of precipitates _in the outer peripheral portion with respect to the number N _in of precipitates in the inside is larger than one.

Here, in the present invention, the above "peripheral portion" and "inside" are defined as portions as shown in FIG. 2 (a). That is, the center position of the radial cross section of the aluminum alloy wire rod 1 is taken as the center X, and a portion having a substantially circular cross section having a radius of half the length r of the radius 2r of the aluminum alloy wire rod is taken as the inside 1a. The portion of the cross-sectional substantially toroidal shape located in the is the outer peripheral portion 1 b (gray scale portion).
Further, as another embodiment, the present invention can be applied to an aluminum alloy stranded wire or an aluminum alloy compressed stranded wire. For example, as shown in FIG. 2 (b), in the aluminum alloy compressed stranded wire 5, the compressed stranded wire in which the strands 6 located at the central portion are not substantially plastically deformed and the strands 7 located at the outer peripheral portion are plastically deformed. It is. Also in this case, as in the case of the aluminum alloy wire rod 1, a cross section having a radius r of half the length r of the radius 2r of the aluminum alloy compressed stranded wire with the center position of the radial cross section of the aluminum alloy compressed stranded wire 5 as the center X A substantially circular portion is an inner portion 5a, and a substantially donut-shaped portion located radially outward of the inner portion 5a is an outer peripheral portion 5b. Then, the number N _out of precipitates in the outer peripheral portion 5 b is larger than the number M _in of precipitates in the inner portion 5 a.

The “precipitate” may be a compound containing at least one of Mg and Si, and representative compounds are Mg ₂ Si, AiFeSi, AlFeMnSi, and AlNiSi. Although Mg-Si clusters are also generated simultaneously with these, they are excluded from the count of the number of the precipitates because clear measurement is difficult in TEM.

Based on such a definition, in the present invention, the number N _out of precipitates having a diameter of 1 μm or less consisting of Mg and Si in the outer peripheral portion is configured to be larger than the number N _in of the precipitates inside. When the wire is subjected to bending deformation, stress is concentrated preferentially to the outer peripheral portion rather than the inner portion, so that a large number of precipitates are present on the outer peripheral portion where stress concentration occurs preferentially, so that bending fatigue characteristics can be obtained. It can be improved.
Here, even when the characteristics are equivalent to those of Patent Document 1, as described above, by using the configuration of the present embodiment, it is possible to significantly reduce the deposition time at the aging heat treatment than before. There are merits, and it is significantly superior to the conventional one in that a large amount of wire can be manufactured in a short period of time particularly when manufacturing a wire harness for mass-produced vehicles.

(4) Characteristics of the aluminum alloy wire rod of this embodiment The aluminum alloy wire rod of this embodiment has a Vickers hardness of 60 to 130 Hv at the outer peripheral portion, a Vickers hardness of 50 to 120 Hv inside, and an outer periphery with respect to Vickers hardness inside The ratio of Vickers hardness of part ((Vickers hardness of outer peripheral part) / (Vickers hardness of inner part)) is greater than 1.0. Thereby, the frequency | count of bending | flexion to the fracture | rupture by the test mentioned later will be 200,000 times or more, and 0.2% proof stress can be made into 250 or less MPa.

In addition, the aluminum alloy wire rod of the present embodiment has such characteristics that the 0.2% proof stress, the bending fatigue property, the conductivity and the tensile strength fall within the following ranges, respectively.
The 0.2% proof stress is preferably 250 MPa or less, more preferably 200 MPa or less, in order to prevent the workability at the time of attaching the wire harness from being lowered.
The bending fatigue property is preferably at least 200,000 times, more preferably at least 400,000 times, in order to withstand repeated bending at the door portion.
The conductivity is preferably 40% IACS or more in order to prevent heat generation due to Joule heat. Further, the conductivity is more preferably 45% IACS or more, further preferably 50% IACS or more, and in this case, it is possible to further reduce the diameter of the wire.
The tensile strength is preferably 200 MPa or more in order to prevent breakage by tensile stress at the time of attachment of the wire harness even when the diameter of the wire is reduced. Further, the tensile strength is more preferably 250 MPa or more, and in this case, the wire can be further reduced in diameter.

  The aluminum alloy wire rod of the present embodiment can be used as an aluminum alloy wire or as an aluminum alloy twisted wire obtained by twisting a plurality of aluminum alloy wires together, and further, an aluminum alloy wire or an aluminum alloy twisted wire It can also be used as a coated electric wire having a coating layer on the outer periphery, and additionally, as a wire harness (combined electric wire) comprising a coated electric wire and a terminal attached to the end of the coated electric wire from which the coating layer is removed. It is also possible to use.

The present invention will be described in detail based on the following examples. The present invention is not limited to the examples shown below.
<Aluminum alloy wire rod>
(Example, Reference Example, Comparative Example)
The contents (% by mass) shown in Table 1 of Mg, Si, Fe and Al and selectively added Ti, B, Cu, Ag, Au, Mn, Cr, Zr, Hf, V, Sc, Co and Ni The melt was subjected to rolling while continuously casting under the conditions shown in Table 2 using a properch-type continuous casting-rolling machine so as to obtain a rod of 9 mm in diameter. Next, this was subjected to a first wire drawing process so as to obtain a predetermined degree of processing. Next, a first heat treatment (intermediate heat treatment) is performed on the processed material subjected to the first wire drawing processing under the conditions shown in Table 2, and further, a predetermined processing degree can be obtained up to a wire diameter of φ 0.3 mm. 2 Wire drawing was done. Next, second heat treatment (solution heat treatment) was performed under the conditions shown in Table 1. In both of the first and second heat treatments, in the batch heat treatment, a wire was wound with a thermocouple to measure the wire temperature. In continuous electric heat treatment, it is difficult in terms of equipment to measure at the part where the temperature of the wire becomes the highest, so it is located in front of the part where the temperature of the wire becomes the highest with a fiber type radiation thermometer (made by Japan Sensor) The temperature was measured, and the maximum temperature reached was calculated in consideration of Joule heat and heat dissipation. In high frequency heating and heat treatment during continuous running, the temperature of the wire near the exit of the heat treatment section was measured. After the second heat treatment, strain was introduced to the outer peripheral portion under the conditions shown in Table 2, and then the third heat treatment (aging heat treatment) was performed under the conditions shown in Table 2 to produce an aluminum alloy wire.

Each characteristic was measured by the method shown below about the manufactured aluminum alloy wire of the Example , the reference example, and the comparative example.

(A) Measurement of 0.2% proof stress and tensile strength In accordance with JIS Z 2241, a tensile test was performed on each of the three test materials (aluminum alloy wire), and the average value was determined. The 0.2% proof stress passes 250MPa or less that does not reduce the work efficiency at the time of wire harness installation, and the tensile strength is to maintain the tensile strength of the crimped portion at the connection of the wire and the terminal. In order to withstand the load applied to the load, the pass level was set to 200 MPa or more.

(B) Conductivity (EC)
Using a four-terminal method, measure the specific resistance of each of the three test materials (aluminum alloy wire) in a constant temperature oven holding a test piece of 300 mm in length at 20 ° C (± 0.5 ° C), The average conductivity was calculated. The distance between the terminals was 200 mm. Conductivity made a passing level 40% IACS or more.

(C) Measurement Method of Flexural Fatigue Properties As a standard of flexural fatigue resistance, strain amplitude at normal temperature was ± 0.17%. Flexural fatigue resistance changes with strain amplitude. When the strain amplitude is large, the fatigue life is short, and when the strain amplitude is small, the fatigue life is long. Since the strain amplitude can be determined by the wire diameter of the wire and the curvature radius of the bending jig, it is possible to set the wire diameter of the wire and the curvature radius of the bending jig arbitrarily to carry out the bending fatigue test. Conduct repeated bending using a jig that gives a bending strain of 0.17% using an omnidirectional bending fatigue tester (apparatus name “repeated bending tester” manufactured by Fujii Seiki (now Fujii), equipment name) Thus, the number of repetitions until breakage was measured. In this example, the number of repetitions until breakage was 200,000 or more.

(D) Measurement method of dispersion density of precipitates composed of Mg and Si compounds Photographs obtained by forming aluminum alloy wires of Examples , Reference Examples and Comparative Examples into thin films by the FIB method and using a transmission electron microscope (TEM) The composition analysis is performed by EDX (Energy Dispersive X-ray Spectroscopy, energy dispersive X-ray spectroscopy) based on the above to identify the constituent elements, and the detected strengths of Mg and Si are in solid solution in the matrix phase The compound which is 10% or more and 1 μm or less with respect to the strength was subjected to counting. The dispersion density of the compound was calculated using the formula of dispersion density of the compound (pieces / μm ² ) = number of compounds (pieces) / counting target range (μm ² ) by setting a range capable of counting 40 or more. . In some cases, a plurality of photographs were used for the counting range. When the number of compounds was so small that 40 or more could not be counted, 1 μm ² was specified and the dispersion density in that range was calculated.

Then, the dispersion density of the compound to be counted was calculated in the outer peripheral portion and in the inside. The sample thickness of the thin film was calculated using 0.15 μm as a reference thickness. When the sample thickness is different from the reference thickness, the sample thickness is converted to the reference thickness, that is, (reference thickness / sample thickness) is multiplied by the area ratio calculated based on the photographed photograph, Area ratio can be calculated. In the present example , the reference example and the comparative example, the sample thickness was set to about 0.15 μm in all samples by the FIB method.

(E) Measurement Method of Vickers Hardness Measurement was performed according to JIS Z 2244: 2009. Specifically, as shown in FIG. 3A, the aluminum alloy wire 2 of a predetermined wire diameter manufactured by the above method is filled with a resin, and thereafter, a cylindrical embedded resin 30 is formed using a wet abrasive paper or the like. The lower surface 30a of the above was polished to obtain a cross section (FIG. 3 (b)). Then, using a Vickers hardness tester (manufactured by Mitutoyo Co., Ltd., device name “HM-125”), measurement was performed at a test force of 0.1 to 1.0 N and a holding time of 15 seconds. As shown in FIG. 3C, the measurement points are three points (positions L1, L2 and L3 in the figure) in the outer peripheral portion 2b of one sample in the cross section of the aluminum alloy wire 2, and one point And the middle position L4). When sufficient space was not able to be ensured, it measured using two or more equivalent samples.

(F) Method of calculating strain amount introduced to outer peripheral portion Assuming that the elongation amount in the longitudinal direction on the outer peripheral portion surface is the strain amount introduced to the outer peripheral portion, the strain amount was calculated by the following equation.
(Amount of distortion) = (R + 2r) / (R + r) × 100-100
(Where R is the bending radius and r is the radius of the aluminum alloy wire)

  The results measured by the above method are shown in Table 1. In Table 1, “A” has a 0.2% proof stress of 200 MPa or less, a bending fatigue frequency of 400,000 or more, a conductivity of 45% IACS or more, and a tensile strength of 250 MPa or more. In addition, “B” has a 0.2% proof stress of 250 MPa or less, a bending fatigue frequency of 200,000 or more, a conductivity of 40% IACS or more, and a tensile strength of 200 MPa or more. In addition, “C” is a case where 0.2% proof stress satisfies at least one of 250 MPa or more, bending fatigue frequency less than 200,000 times, conductivity less than 40% IACS, and tensile strength less than 200 MPa. .

From the results of Table 2, the following is clear. All of the aluminum alloy wires of Reference Example 1 and Examples 1 to 3 had high tensile strength and conductivity, low 0.2% proof stress, and were superior in bending fatigue properties to the prior art.

On the other hand, in Comparative Example 1, no strain is applied to the outer peripheral surface, and the number N _out of precipitates in the outer peripheral portion is the same as the number M _in of precipitates inside, and the number of bending fatigue is out of the range of the present invention Met. In Comparative Example 2, the strain amount on the surface of the outer peripheral portion is 0.1%, but the number N _out of precipitates in the outer peripheral portion is the same as the number M _in of precipitates in the inside, and the number of bending fatigue times of the present invention is It was out of range. In Comparative Example 3, the strain amount of the outer peripheral surface was 20%, and the 0.2% proof stress was outside the range of the present invention.

<Aluminum alloy stranded wire>
The contents (mass%) shown in Table 3 are Mg, Si, Fe and Al, and selectively added Ti, B, Cu, Ag, Au, Mn, Cr, Zr, Hf, V, Sc, Co and Ni. The melt was subjected to rolling while continuously casting under the conditions shown in Table 4 using a properch-type continuous casting-rolling machine so as to obtain a rod of φ 9 mm. Next, this was subjected to a first wire drawing process so as to obtain a predetermined degree of processing. Next, a first heat treatment (intermediate heat treatment) is performed on the processed material subjected to the first wire drawing processing under the conditions shown in Table 4, and further, a predetermined processing degree is obtained up to a wire diameter of φ 0.3 mm. 2 Wire drawing was done. Next, after a 7-twist stranding step, the strand was compressed to obtain a compressed strand. The second heat treatment (solution heat treatment) was performed under the conditions shown in Table 4, and in both the first and second heat treatments, a thermocouple was wound around the wire in the batch heat treatment to measure the wire temperature. In continuous electric heat treatment, it is difficult in terms of equipment to measure at the part where the temperature of the wire becomes the highest, so it is located in front of the part where the temperature of the wire becomes the highest with a fiber type radiation thermometer (made by Japan Sensor) The temperature was measured, and the maximum temperature reached was calculated in consideration of Joule heat and heat dissipation. In high frequency heating and heat treatment during continuous running, the temperature of the wire near the exit of the heat treatment section was measured. After the second heat treatment, strain was introduced to the outer peripheral portion under the conditions shown in Table 4, and then the third heat treatment (aging heat treatment) was performed under the conditions shown in Table 4 to produce an aluminum alloy wire.
Each characteristic was measured by the method similar to the above about the produced aluminum alloy compression twisted wire of the Example , the reference example, and the comparative example. In addition, about the measuring method of Vickers hardness, as a measurement location, as shown in FIG. 4, in the cross section of aluminum alloy compression twisted wire 5, one sample 3 points (per position L1, L2, in the figure per 1 sample) L3), one point (position L4 in the figure) in the inside 5a. When sufficient space was not able to be ensured, it measured using two or more equivalent samples. The results are shown in Table 4.

From the results of Table 4, the following is clear. All of the aluminum alloy compressed stranded wires of Examples 5 to 7 had high tensile strength and conductivity, low 0.2% proof stress, and were superior in bending fatigue properties to the conventional ones.

On the other hand, in Comparative Example 4, the Mg content is out of the range of the present invention, the strain amount of the surface of the outer peripheral portion is 2%, and the number N _out of the precipitates in the outer peripheral portion is more than the number M _in of the precipitates inside Although many, the conductivity was out of the scope of the present invention. In Comparative Example 5, the Si content is outside the range of the present invention, the strain amount of the surface of the outer peripheral portion is 2%, and the number N _out of the precipitates in the outer peripheral portion is larger than the number M _in of the precipitates inside The conductivity is out of the scope of the present invention. In Comparative Example 6, the Si content was out of the range of the present invention, and the distortion amount of the outer peripheral surface was 2%, but the solution treatment temperature was out of the range of the present invention and the wire was broken during wire drawing.

  The aluminum alloy wire rod of the present invention is premised on using an aluminum alloy containing Mg and Si, and high tensile strength and high tensile strength even when used as a thin wire having a wire diameter of 0.5 mm or less. It is possible to improve the wire handling property while securing the conductivity. Therefore, it is useful as a battery cable mounted on a mobile body, a wire harness or a lead for a motor, and a wiring body of an industrial robot. Furthermore, since the aluminum alloy wire of the present invention has high bending fatigue properties, the wire diameter can be made smaller than that of the conventional wire, and a wire having such characteristics or a wire harness using the wire It is extremely useful as a component for mass-produced vehicles and the like in that it can shorten the manufacturing process time and improve the mass productivity.

DESCRIPTION OF SYMBOLS 1 aluminum alloy wire rod 1 'aluminum alloy wire rod 2 aluminum alloy wire 1a internal 1b outer peripheral part 5 aluminum alloy compression twisted wire 6 strand 7 strand 5a internal 5b outer peripheral part 10 jig 10a outer surface 20 dice 20a hole 30 embedded resin 30a lower surface

Claims (17)

Mg: 0.1 to 1.0% by mass, Si: 0.1 to 1.2% by mass, Fe: 0.01 to 1.40% by mass, Ti: 0 to 0.100% by mass, B: 0 to 0 0.030 mass%, Cu: 0 to 1.00 mass%, Ag: 0 to 0.50 mass%, Au: 0 to 0.50 mass%, Mn: 0 to 1.00 mass%, Cr: 0 to 1.00 mass%, Zr: 0 to 0.50 mass%, Hf: 0 to 0.50 mass%, V: 0 to 0.50 mass%, Sc: 0 to 0.50 mass%, Co: 0 to 0 0.50 mass%, Ni: 0 to 0.50 mass%, balance: Al and chemical composition consisting of unavoidable impurities,
The chemical composition is Cu: 0.01 to 1.00% by mass, Ag: 0.01 to 0.50% by mass, Au: 0.01 to 0.50% by mass, Mn: 0.01 to 1.00 Mass%, Cr: 0.01 to 1.00 mass%, Zr: 0.01 to 0.50 mass%, Hf: 0.01 to 0.50 mass%, V: 0.01 to 0.50 mass% And Sc: 0.01 to 0.50 mass%, Co: 0.01 to 0.50 mass%, and Ni: 0.01 to 0.50 mass%. One or more selected from the group consisting of Contains
Mg and / or diameter 1μm following precipitation the number Nout containing Si in the outer peripheral portion is rather multi than Mg and / or diameter 1μm following precipitation the number Nin containing Si inside,
Tensile strength is 200 MPa or more, conductivity is 40% IACS or more, 0.2% proof stress is 250 MPa or less,
Some of Mg and Si, and wherein the precipitation child as a beta double prime phase together, the aluminum alloy wire. Mg: 0.1 to 1.0% by mass, Si: 0.1 to 1.2% by mass, Fe: 0.01 to 1.40% by mass, Ti: 0 to 0.100% by mass, B: 0 to 0 0.030 mass%, Cu: 0 to 1.00 mass%, Ag: 0 to 0.50 mass%, Au: 0 to 0.50 mass%, Mn: 0 to 1.00 mass%, Cr: 0 to 1.00 mass%, Zr: 0 to 0.50 mass%, Hf: 0 to 0.50 mass%, V: 0 to 0.50 mass%, Sc: 0 to 0.50 mass%, Co: 0 to 0 0.50 mass%, Ni: 0 to 0.50 mass%, balance: Al and chemical composition consisting of unavoidable impurities,
The chemical composition contains Ni: 0.01 to 0.50 mass%,
The number Nout of precipitates having a diameter of 1 μm or less containing Mg and / or Si at the outer peripheral portion is larger than the number Nin of precipitates having a diameter of 1 μm or less containing Mg and / or Si inside;
An aluminum alloy wire characterized by having a tensile strength of 200 MPa or more, a conductivity of 40% IACS or more, and a 0.2% proof stress of 250 MPa or less. Vickers hardness of the outer peripheral portion is 60～130Hv, an internal Vickers hardness 50～120Hv, and is greater than 1.0 the ratio of the Vickers hardness of the outer peripheral portion to the interior of the Vickers hardness, according to claim 1 or 2 Aluminum alloy wire rod as described. The said chemical composition contains 1 type or 2 types selected from the group which consists of Ti: 0.001-0.100 mass% and B: 0.001-0.030 mass% . aluminum alloy wire mounting serial to any one. The aluminum alloy wire rod according to claim 1, wherein the chemical composition contains Ni: 0.01 to 0.50 mass%.   The total content of Fe, Ti, B, Cu, Ag, Au, Mn, Cr, Zr, Hf, V, Sc, Co, Ni is 0.01 to 2.00% by mass. Aluminum alloy wire according to any one of the above.   The aluminum alloy wire according to any one of claims 1 to 6, which is an aluminum alloy wire having a wire diameter of 0.1 to 0.5 mm. Mg: 0.1 to 1.0% by mass, Si: 0.1 to 1.2% by mass, Fe: 0.01 to 1.40% by mass, Ti: 0 to 0.100% by mass, B: 0 to 0 0.030 mass%, Cu: 0 to 1.00 mass%, Ag: 0 to 0.50 mass%, Au: 0 to 0.50 mass%, Mn: 0 to 1.00 mass%, Cr: 0 to 1.00 mass%, Zr: 0 to 0.50 mass%, Hf: 0 to 0.50 mass%, V: 0 to 0.50 mass%, Sc: 0 to 0.50 mass%, Co: 0 to 0 An aluminum alloy twisted wire constituted by twisting a plurality of aluminum alloy wires having a chemical composition consisting of 0.50 mass%, Ni: 0 to 0.50 mass%, balance: Al and unavoidable impurities,
The chemical composition is Cu: 0.01 to 1.00% by mass, Ag: 0.01 to 0.50% by mass, Au: 0.01 to 0.50% by mass, Mn: 0.01 to 1.00 Mass%, Cr: 0.01 to 1.00 mass%, Zr: 0.01 to 0.50 mass%, Hf: 0.01 to 0.50 mass%, V: 0.01 to 0.50 mass% And Sc: 0.01 to 0.50 mass%, Co: 0.01 to 0.50 mass%, and Ni: 0.01 to 0.50 mass%. One or more selected from the group consisting of Contains
Mg and / or diameter 1μm following precipitation the number Nout containing Si in the outer peripheral portion is rather multi than Mg and / or diameter 1μm following precipitation the number Nin containing Si inside,
Tensile strength is 200 MPa or more, conductivity is 40% IACS or more, 0.2% proof stress is 250 MPa or less,
Aluminum alloy stranded wire characterized in that Mg and part of Si precipitate together as a beta double prime phase . Mg: 0.1 to 1.0% by mass, Si: 0.1 to 1.2% by mass, Fe: 0.01 to 1.40% by mass, Ti: 0 to 0.100% by mass, B: 0 to 0 0.030 mass%, Cu: 0 to 1.00 mass%, Ag: 0 to 0.50 mass%, Au: 0 to 0.50 mass%, Mn: 0 to 1.00 mass%, Cr: 0 to 1.00 mass%, Zr: 0 to 0.50 mass%, Hf: 0 to 0.50 mass%, V: 0 to 0.50 mass%, Sc: 0 to 0.50 mass%, Co: 0 to 0 An aluminum alloy twisted wire constituted by twisting a plurality of aluminum alloy wires having a chemical composition consisting of 0.50 mass%, Ni: 0 to 0.50 mass%, balance: Al and unavoidable impurities,
The chemical composition contains Ni: 0.01 to 0.50 mass%,
The number Nout of precipitates having a diameter of 1 μm or less containing Mg and / or Si at the outer peripheral portion is larger than the number Nin of precipitates having a diameter of 1 μm or less containing Mg and / or Si inside;
An aluminum alloy twisted wire characterized by having a tensile strength of 200 MPa or more, a conductivity of 40% IACS or more, and a 0.2% proof stress of 250 MPa or less. A coated wire having a coating layer on the outer periphery of the aluminum alloy wire rod according to claim 1 or 2 or the aluminum alloy stranded wire according to claim 8 or 9 . A wire harness comprising: the coated electric wire according to claim 10 ; and a terminal attached to the end of the coated electric wire from which the cover layer is removed. Dissolved, after casting, after hot working to form a wire rod, then at least drawing, solution heat treatment, according to any one of claims 1 to 7 for performing the steps of the strain introduction treatment and aging heat treatment A method of manufacturing an aluminum alloy wire rod of
The solution heat treatment is heated to a predetermined temperature within the range of 450 to 580 ° C., and then cooled to a temperature of at least 150 ° C. at an average cooling rate of 10 ° C./s or more. Introduce strain into the outer periphery of the wire after the annealing heat treatment and before the aging heat treatment,
The aging heat treatment comprises heating to a predetermined temperature in the range of 100 ~ 0.99 ° C., and wherein the Rukoto was also deposited at the same time the beta double prime phase, A aluminum production process of the alloy wire. The method for producing an aluminum alloy wire according to claim 12 , wherein the strain introducing process introduces strain to an outer peripheral portion of the wire by bending the wire. The strain introduction process 1 performs processing rate per pass of 10% or less is drawing process one or more times, to introduce distortion to the outer peripheral portion of the wire at a total working ratio of 10% or less, according to claim 12, wherein Method of manufacturing aluminum alloy wire rod After melting and casting, a rough wire is formed through hot working, and then at least the steps of wire drawing, solution heat treatment, strain introduction treatment and aging heat treatment are sequentially carried out, and wire drawing of the wire is further carried out A manufacturing method of an aluminum alloy stranded wire which is performed after wire processing and before the aging heat treatment,
The solution heat treatment is heated to a predetermined temperature in the range of 450 to 580 ° C., and then cooled to a temperature of at least 150 ° C. at an average cooling rate of 10 ° C./s or more. Introduce strain into the outer periphery of the wire or stranded wire after wire processing and before the aging heat treatment,
The aging heat treatment comprises heating to a predetermined temperature in the range of 100 ~ 0.99 ° C., and wherein the Rukoto was also deposited at the same time the beta double prime phase, the production method according to claim 8 or 9, wherein the aluminum alloy stranded wire. The method for manufacturing an aluminum alloy stranded wire according to claim 15 , wherein the strain introducing process introduces strain to an outer peripheral portion of the wire rod or the stranded wire by bending the wire rod. The strain introduction processing is performed by performing drawing once or a plurality of times in which the processing rate per pass is 10% or less, and introducing a strain to the outer peripheral portion of the wire or stranded wire with a total processing rate of 10% or less Item 16. A method for producing an aluminum alloy stranded wire according to item 15 .

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