JP2010163675A - Aluminum alloy wire rod - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aluminum alloy wire excellent in bending fatigue resistance.
SO, Fe is 0.1 to 0.4 mass%, Cu is 0.1 to 0.3 mass%, Mg is 0.02 to 0.2 mass%, and Si is 0.02 to 0.2 mass%. Is an aluminum alloy wire composed of 0.001 to 0.01 mass% of Ti and V, the balance being Al and inevitable impurities, and is used by being mounted on a moving vehicle body. An aluminum alloy wire having a crystal grain size of 5 to 25 μm in a vertical cross section in the linear direction and a fatigue life of 50000 times or more when subjected to repeated fatigue at a strain amplitude of ± 0.15% at room temperature.
[Selection figure] None

Description

  The present invention relates to an aluminum alloy wire used as a conductor of an electric wiring body.

2. Description of the Related Art Conventionally, a member in which a terminal (connector) made of copper or copper alloy (for example, brass) is attached to an electric wire including a copper or copper alloy conductor called a wire harness as an electric wiring body of a moving body such as an automobile, a train, and an aircraft However, in light of the recent weight savings of moving bodies, studies are underway to use aluminum or aluminum alloys that are lighter than copper or copper alloys as conductors of electrical wiring bodies.
The specific gravity of aluminum is about 1/3 of copper, and the electrical conductivity of aluminum is about 2/3 of copper (pure aluminum is about 66% IACS when pure copper is used as the standard of 100% IACS). In order to pass the same current as that of a pure copper conductor wire, the cross-sectional area of the pure aluminum conductor wire needs to be about 1.5 times that of the pure copper conductor wire, but the weight is still about half that of copper. There are advantages.
In addition, said% IACS represents the electrical conductivity when the resistivity 1.7241 × 10 ⁻⁸ Ωm of universal standard soft copper (International Announced Copper Standard) is 100% IACS.

There are several problems in using the aluminum as a conductor of an electric wiring body of a moving body, and one of them is improvement of bending resistance (fatigue characteristics). This is because the movable body is generally accompanied by an openable door or door. For example, when the moving body is an automobile, the wire harness connecting the vehicle body and the door is repeatedly fatigued each time it is opened and closed. It is said that the number of times is from tens of thousands to hundreds of thousands of times. With this number of repetitions, pure copper (tough pitch copper) that has been conventionally used as a wire harness conductor is considered to have no problem because it has excellent fatigue characteristics, but it is a severe number for low-strength aluminum. For this reason, it is not possible to withstand a wire using pure aluminum as used in conventional overhead wires.
The amplitude of the strain applied to the opening and closing is a relatively loose strain amount of ± 0.1 to 0.2%, but the strain amount is several orders of magnitude higher than that of an overhead electric wire.
Therefore, unlike an installation environment such as an overhead wire or power cable, the electric wiring body of the mobile body often generates high bending strain, which strongly improves the characteristics of the electric wiring body for the mobile body itself. It is one of the required factors.

The aluminum conductor used in the electric wiring body of the moving body is required to have bending resistance in a portion that receives repeated bending stress such as a door. Metallic materials such as aluminum cause fatigue fracture. This is the same as fatigue failure that breaks a certain number of times when a sufficiently low load is repeatedly applied to a test piece made of a metal material.
Generally, it is said that a material having higher strength has better fatigue characteristics. Therefore, high-strength aluminum wire may be applied, but wire harnesses are generally required to be easy to handle (installation work on the vehicle body) at the time of installation. ) Is often used.
Further, as a method for increasing the strength, there is a solid solution strengthening method. However, this reduces the electrical conductivity, so that there is a limit to the amount of addition in order to obtain a large strengthening amount.
Therefore, an aluminum conductor used for an electric wiring body of a moving body is required to have a material excellent in bending fatigue characteristics in addition to strength and conductivity.

  For such applications, the aluminum wires for power transmission lines 1060 and 1070 among commercially available pure aluminum (1000 series) cannot sufficiently withstand the amplitude fatigue caused by opening and closing of doors and the like. In addition, although alloying with various additive elements has been studied, it is a well-known fact that alloying causes a decrease in conductivity. Therefore, in consideration of conductivity, the 3000 series and 5000 series having excellent strength cannot be used, and other alloy systems are not good.

  On the other hand, as an aluminum conductor used for an electric wiring body of a moving body, Patent Documents 1 to 17 describe an example mainly used for an automobile wire harness.

When the aluminum conductor is used for an opening / closing part, if the bending fatigue characteristics are poor, there is a concern that the conductor may break during use, and in order to maintain its reliability, a conductor excellent in high bending characteristics is required. . For that purpose, improvement of strength is one method, but the alloys listed in Patent Documents 1 to 17 that have been improved in strength by alloying satisfy the characteristics and cost required for mobile applications. It couldn't be said.
In particular, in the alloys added with Zr described in Patent Documents 1, 4, 17, etc., the Zr addition method is difficult, and the Al ₃ Zr intermetallics whose properties are controlled by performing heat treatment for a long time. On the other hand, the process of forming a compound is necessary, and on the other hand, the conductor described in Patent Document 3 is a composite material.

JP 2004-311102 A JP 2006-12468 A Japanese Patent No. 3530181 JP 2005-336549 A JP 2006-12468 A JP 2004-134212 A JP 2005-174554 A JP 2006-19164 A JP 2006-4752 A JP 2006-79885 A JP 2006-19165 A JP 2006-19163 A Japanese Patent Laid-Open No. 2006-4760 JP 2006-253109 A JP 2006-4757 A JP 2006-79886 A JP 2000-357420 A

  An object of the present invention is to provide an aluminum alloy wire excellent in bending fatigue resistance.

  In view of such a situation, the present inventors have evaluated the desirable bending fatigue properties and the fatigue properties required in the test method as components contained in aluminum and in a vertical section in the drawing direction. Study the relationship between the crystal grain size, the particle size of intermetallic compound particles to be dispersed (compound particle diameter) and their dispersion density, as well as the properties of tensile strength and conductivity, and specify the particle size and dispersion density appropriately. As a result, the inventors have found that the above characteristics can be improved, and have further studied based on this finding to complete the present invention.

That is, the present invention
(1) 0.1 to 0.4 mass% Fe, 0.1 to 0.3 mass% Cu, 0.02 to 0.2 mass% Mg, 0.02 to 0.2 mass% Si, And an aluminum alloy wire comprising 0.001 to 0.01 mass% of Ti and V in combination, the balance being Al and unavoidable impurities, the crystal grain size in the vertical cross section in the wire drawing direction being 5 to 5. An aluminum alloy wire having a fatigue life of 50,000 times or more when subjected to repeated fatigue of 25 μm and a strain amplitude of ± 0.15% at room temperature,
(2) containing 0.3 to 0.8 mass% of Fe and one or more elements selected from the group consisting of Cu, Mg, and Si in total of 0.02 to 1.0 mass%, It is an aluminum alloy wire comprising 0.001 to 0.01 mass% of Ti and V in total, the balance being Al and inevitable impurities, the crystal grain size in the vertical cross section in the wire drawing direction is 5 to 30 μm, and at room temperature An aluminum alloy wire having a fatigue life of 50000 times or more when subjected to repeated fatigue with a strain amplitude of ± 0.15%,
(3) The distribution density of the second layer particles having a tensile strength of 80 MPa or more and an electrical conductivity of 55% IACS or more, and the size of the second phase particles dispersed in the wire rod is 50 to 500 nm in terms of particle size. features 1-10 is ^two / [mu] m ² (1) or (2) above, wherein the aluminum alloy wire, and (4) the wire is a mobile body, battery cable, harnesses or to be used as a motor for wire, The aluminum alloy wire according to any one of (1) to (3) is provided.

  The aluminum alloy wire of the present invention has excellent bending fatigue resistance and is useful as a battery cable, harness or motor conductor mounted on a moving body, and is particularly suitable for doors, trunks, bonnets and the like that require excellent flexibility. It can be used suitably.

It is explanatory drawing of the repetition break frequency test of an Example.

  The aluminum alloy wire according to the first preferred embodiment of the present invention has Fe of 0.1 to 0.4 mass%, Cu of 0.1 to 0.3 mass%, and Mg of 0.02 to 0.2 mass%. An aluminum alloy wire containing Si in an amount of 0.02 to 0.2 mass%, further including 0.001 to 0.01 mass% of Ti and V in combination, the balance being Al and inevitable impurities, A wire rod mounted on and used for a wire having a crystal grain size of 5 to 25 μm in a vertical cross section in the wire drawing direction and a fatigue life of 50000 when subjected to repeated fatigue with a strain amplitude of ± 0.15% at 20 ° C. It is an aluminum alloy wire that is 10,000 times or more.

  In this embodiment, the content of Fe is 0.1 to 0.4 mass%. Fe is dissolved in aluminum only at 0.05 mass% at 655 ° C. in the aluminum, and the rest is Al—Fe, This is because crystallization occurs as an intermetallic compound such as Al-Fe-Si, Al-Si-Mg, and Al-Fe-Cu-Si. Since this crystallized substance improves the strength and controls the crystal grain size, the Fe content is not sufficient if it is less than 0.1 mass%. Moreover, when it exceeds 0.4 mass%, the effect is saturated and is not industrially desirable. The content of Fe is preferably 0.15 to 0.3 mass%, more preferably 0.18 to 0.25 mass%.

  In the present embodiment, the reason why the Cu content is 0.1 to 0.3 mass% is because Cu is solid-solved and strengthened in the aluminum base material. In that case, if the Cu content is less than 0.1 mass%, the effect cannot be exerted, and if the Cu content exceeds 0.3 mass%, the conductivity decreases. Moreover, when there is much content of Cu, other elements will form an intermetallic compound, and malfunctions, such as generation | occurrence | production of the noro (slag) at the time of melt | dissolution, will arise. The Cu content is preferably 0.15 to 0.25 mass%, more preferably 0.18 to 0.22 mass%.

  In this embodiment, the content of Mg is 0.02 to 0.2 mass% because Mg is strengthened by solid solution in the aluminum base material, and part of it forms precipitates with Si. Strength can be improved. If the Mg content is less than 0.02 mass%, there is no effect, and if it exceeds 0.2 mass%, the conductivity is lowered and the effect is saturated. Moreover, when there is much content of Mg, other elements will form an intermetallic compound, and malfunctions, such as generation | occurrence | production of the noro at the time of melt | dissolution, will arise. The Mg content is preferably 0.05 to 0.15 mass%, more preferably 0.08 to 0.12 mass%.

  In the present embodiment, the Si content is set to 0.02 to 0.2 mass%, as described above, Si forms a compound with Mg to improve the strength. If the Si content is less than 0.02 mass%, there is no effect, and if it exceeds 0.2 mass%, the conductivity is lowered and the effect is saturated. Moreover, when there is much content of Si, other elements will form an intermetallic compound, and malfunctions, such as generation | occurrence | production of the noro at the time of melt | dissolution, will arise. The Si content is preferably 0.05 to 0.15 mass%, more preferably 0.08 to 0.12 mass%.

  In this embodiment, both Ti and V act as ingot refining materials during melt casting. If the structure of the ingot is coarse, cracks are generated in the next processing step, which is not industrially desirable. Therefore, Ti and V are added to refine the ingot structure. When the total content of Ti and V is less than 0.001 mass%, the effect of miniaturization is not observed. When the content exceeds 0.01 mass%, the conductivity is greatly reduced and the effect is saturated. The total content of Ti and V is preferably 0.05 to 0.08 mass%, more preferably 0.06 to 0.08 mass%. Moreover, when using together Ti and V, the ratio is Ti: V (mass ratio), Preferably it is 10: 1-10: 3.

  In a second preferred embodiment of the present invention, Fe is 0.3 to 0.8 mass%, and one or more elements selected from the group consisting of Cu, Mg, and Si are 0.02 to 1.0 mass% in total. Is an aluminum alloy wire composed of 0.001 to 0.01 mass% of Ti and V in combination, and the balance Al and inevitable impurities, and is a wire rod mounted on a moving vehicle body, An aluminum alloy wire having a crystal grain size of 5 to 30 μm in a vertical cross section in the wire drawing direction and a fatigue life of 50000 times or more when subjected to repeated fatigue with a strain amplitude of ± 0.15% at 20 ° C.

In the second embodiment, among the alloy compositions of the first embodiment described above, by controlling the total amount of Cu, Mg, and Si added to 0.02 to 1.0 mass%, the inexpensive Fe is reduced to 0. Fe also has the effect of compensating for the weight loss by increasing to 3 to 0.8 mass%. However, even when Cu, Mg, and Si are controlled, there is no effect at 0.3 mass% or less, and at 0.8 mass% or more, the amount of crystallized substances increases and the effect is saturated. In addition, if the addition amount is large, an intermetallic compound is formed with other elements, and problems such as generation of noro during melting occur.
In the second embodiment, Fe is preferably 0.4 to 0.8 mass%, more preferably 0.5 to 0.7 mass%. The total of elements selected from one or more elements among Cu, Mg, and Si is preferably 0.4 to 0.8 mass%, more preferably 0.5 to 0.7 mass%.
Other alloy compositions are the same as those in the first embodiment described above.

In the aluminum alloy wire of the present invention, the crystal grain size other than the above components is strictly defined. Further, the fatigue life (flexural characteristics) when cyclic fatigue with a strain amplitude of ± 0.15% at room temperature is specified.
Here, normal temperature refers to about 20 ° C. (20 ° C. ± 5 ° C.).

(Crystal grain size)
The crystal grain size in the vertical cross section in the wire drawing direction of the aluminum alloy wire of the first embodiment of the present invention is 5 to 25 μm, preferably 8 to 15 μm, more preferably 10 to 12 μm. Moreover, the crystal grain diameter in the vertical cross section of the wire drawing direction of the wire of the aluminum alloy wire of a 2nd embodiment is 5-30 micrometers, Preferably it is 8-15 micrometers, More preferably, it is 10-12 micrometers. If the crystal grain size is too small, the partially recrystallized structure remains and the elongation is remarkably reduced. If the crystal grain size is too large, the deformation behavior becomes non-uniform, and the elongation is similarly reduced. This is because a problem occurs when joining (fitting).
In the present invention, the crystal grain size means an average grain size.

(Bending characteristics)
In the present invention, the fatigue life when subjected to repeated fatigue with a strain amplitude of ± 0.15% at room temperature (about 20 ° C.) is 50000 times or more, preferably 70000 times or more, more preferably 80000 times or more. It is.
The reason for the vibration having a strain amplitude of ± 0.15% at room temperature as a standard for flexibility is ε = 0.2 to 0.25% when the strain of the door portion of an existing moving vehicle body (car) is measured. . Therefore, if the fatigue test data is acquired under more severe conditions of ± 0.15%, that is, the amplitude width is doubled to 0.3%, the bending characteristics can be sufficiently evaluated.
Further, if the fatigue life is 50000 times or more, when considering the use of a car, the number of times of opening and closing per day is 10 times, and it can be used even for 10 years. If the wire diameter is increased, the amount of strain increases even if the bending radius is the same, and the fatigue life until fracture is deteriorated. Conversely, if the wire diameter is reduced, the fatigue life is improved.

(Dimension and distribution density of the second phase)
The second phase is a particle such as a crystallized product or a precipitate that exists in the crystal grains. The crystallized material is mainly formed during melt casting, and the precipitate is formed by intermediate heat treatment, for example, particles such as Al—Fe, Al—Fe—Si, and Si—Mg.
The second phase particles are distributed with a size of several nm to several μm. In the present invention, the size and density of the second phase particles having high effect on the bending life characteristics are defined. that is,
The dimension of the second phase particles is 50 to 500 nm, preferably 100 to 300 nm, in terms of particle size. In the present invention, the dimension of the second phase particles means an average dimension. The particle diameter in terms of particle diameter is an equivalent volume sphere equivalent diameter.

By controlling the size and density of the second phase, desired bending characteristics (fatigue characteristics) can be obtained. Various crystallized substances are formed in the aluminum alloy at the time of melting and casting, but if they are coarse, there are many occurrences of noro and there is an industrial problem at the time of melting and casting. Further, if it is fine, there is a concern that the strength is increased and the conductivity is lowered. Therefore, when the second phase whose particle size is smaller than 50 nm in terms of particle size increases, the strength increases, and the wire drawing process becomes difficult. On the other hand, even if the second phase larger than 500 nm increases, it causes disconnection and makes wire drawing difficult.
In the present invention, the dimensions of the second phase particles are measured by controlling the cooling rate during melt casting, the temperature of the intermediate heat treatment, and the cooling rate.

Furthermore, the distribution of two-phase particles (dispersion) density of 1-10 ² / [mu] m ^2, preferably 10 to 50 / [mu] m ^2. If the dispersion density of the second phase particles is less than 1 particle / μm ² , it is difficult to obtain a desired number of bendings, and if it is greater than 10 ² particles / μm ² , the drawing process becomes difficult.
In the present invention, the dispersion density of the second phase particles is measured by controlling the cooling rate during melt casting, the temperature of the intermediate heat treatment, and the cooling rate.

  The size and density of the second phase can be controlled by the component (addition amount) of the additive element and the cooling rate during solidification. If it is in the additive component range of the present application, the cooling rate at the time of melt casting is 0.1 to 100 ° C./second, more preferably 5 to 50 ° C./second, so that a desired distribution state of the second phase can be obtained. it can. This cooling rate is an average cooling rate from the start of solidification to 200 ° C. Examples of the method for changing the cooling rate include the following methods. (1) Change the size (wall thickness) of the iron mold. (2) A water-cooled mold is provided on the lower surface of the mold and forcedly cooled. (Cooling rate also changes by changing the amount of water). (3) Reduce the amount of molten metal cast.

(Tensile strength and conductivity)
The aluminum alloy wire of the present invention has a tensile strength (TS) of 80 MPa or more and a conductivity of preferably 55% IACS or more, and more preferably a tensile strength of 80 to 150 MPa and a conductivity of 55 to 65%. IACS, more preferably, the tensile strength is 100 to 120 MPa and the conductivity is 58 to 62% IACS.
Tensile strength and electrical conductivity have contradictory properties. The higher the tensile strength, the lower the electrical conductivity, and conversely, pure aluminum with a low tensile strength has a higher electrical conductivity. Therefore, when an aluminum conductor is considered, if the tensile strength is 80 MPa or less, it is weak including handling and difficult to use as an industrial conductor. Further, the conductivity is preferably 55% IACS or more because a high current of several tens of A (amperes) flows when used for a power line.

  The aluminum wire of the present invention can be easily manufactured through each process of melting, hot or cold processing (groove roll processing, etc.), wire drawing and heat treatment (annealing) according to a conventional method.

  For example, the aluminum alloy wire of the first embodiment can be produced as follows. Fe 0.1-0.4 mass%, Cu 0.1-0.3 mass%, Mg 0.02-0.2 mass%, Si 0.02-0.2 mass%, Ti and V in total 0.001 to 0.01 mass% and the remaining aluminum are melted and cast to produce an ingot. The ingot is subjected to hot groove roll rolling to obtain a bar. Next, the surface can be peeled, the workpiece obtained by cold drawing is subjected to heat treatment, further drawn, and finally subjected to annealing heat treatment.

  Moreover, the aluminum alloy wire of the second embodiment can be produced, for example, as follows. Fe is 0.3 to 0.8 mass%, further, elements selected from one or more elements among Cu, Mg, and Si are 0.02 to 1.0 mass% in total, and Ti and V are 0.001 in total. The remaining aluminum is melted and cast to produce an ingot, containing ~ 0.01 mass%. This ingot is subjected to hot groove roll rolling to obtain a bar of about 10 mmφ. Next, the surface can be peeled, and the cold drawn material obtained by cold drawing can be subjected to heat treatment, further drawn, and finally subjected to annealing heat treatment.

  Hereinafter, the present invention will be described in detail with reference to examples. In addition, this invention is not limited to the Example shown below.

Examples 1-22 and Comparative Examples 1-20
Fe, Cu, Mg, Si, Ti, V, and Al were dissolved in a silicon crucible using a graphite crucible in the amounts (mass%) shown in Tables 1 and 2, and this was cooled at a cooling rate of 10 to 300 ° C./second. And an inch bar ingot of 25 × 25 mm × 300 mm was manufactured. At this time, a K-type thermocouple was set inside the mold so that the temperature could be continuously monitored every 0.5 seconds, and an average cooling rate from solidification to 200 ° C. was obtained later. This ingot was subjected to hot groove roll rolling to obtain a bar of about 10 mmφ. Next, the surface is peeled to 9 to 9.5 mmφ, and this is cold drawn to 2.6 mmφ. This cold-drawn workpiece is subjected to an intermediate heat treatment at a temperature of 300 to 400 ° C. for 1 to 4 hours, further drawn to 0.3 mmφ, and finally at a temperature of 300 to 400 ° C. for 1 to 4 hours. The aluminum or aluminum alloy wire was produced. In addition, the cooling rate at the time of intermediate heat processing shall be 1-20 degrees C / min. This cooling rate is an average rate from the heat treatment temperature to 100 ° C., and can be controlled to some extent by a program for controlling the furnace body, for example.

  Each characteristic was measured by the method described below about the produced wire of each Example and a comparative example. The results are shown in Tables 1-2.

(A) Crystal grain size The cross section of the specimen cut out from the wire drawing direction was filled with resin, and after mechanical polishing, electrolytic polishing was performed. The electrolytic polishing conditions were an ethanol solution containing 20% perchloric acid, a liquid temperature of 0 to 5 ° C., a current of 10 mA, a voltage of 10 V, and a time of 30 to 60 seconds. This structure was observed and photographed with an optical microscope of 200 to 400 times, and the particle size was measured by a crossing method. Specifically, the photographed photograph was stretched about 4 times, a straight line was drawn, and the number of intersections of the straight line and the grain boundary was measured to obtain the average particle diameter. The grain boundaries were evaluated by changing the length and number of straight lines so that 100 to 200 grains could be counted.
(B) Second phase particle size (particle diameter) and distribution density (particle density)
The wire rods of the examples and comparative examples were made into thin films by the electrolytic polishing thin film method (twin jet polishing method), and an arbitrary field of view was observed at a magnification of 2000 to 10,000 using a transmission electron microscope (TEM), and arbitrarily three sheets It was obtained by taking a photo of and analyzing the photo. At this time, (111) or (200) was used as the incident azimuth angle.
The size (PPT: Particle of Precipitation) and distribution density (PPT × 10 ² ) were calculated by counting about 50 to 1000 second phase particles. When the size of the particles is large, the number of particles decreases. When the particle size is extremely small, the field of view is added with three more fields. The photograph taken was analyzed by an image analyzer, and the number of second phase particles and the average size were calculated.
(C) Tensile strength (TS)
Three test pieces cut out from the wire drawing direction were tested in accordance with JIS Z 2241, and the average value was obtained.
(D) Conductivity (EC)
A test piece having a length of 350 mm cut out from the wire drawing direction was immersed in a constant temperature bath maintained at 20 ° C. (± 0.5 ° C.), and its specific resistance was measured using a four-terminal method to calculate conductivity. The distance between terminals was 300 mm.
(E) Number of repeated fractures Repeated bending using a double-bending bending fatigue tester manufactured by Ishikawa Gear Industry Co., Ltd. (currently F-Techno Co., Ltd.) using a jig that gives a bending strain of 0.15%. By repeating the above, the number of repeated breaks was measured. The repeated bending angle is set to ± 35 ° (full angle 70 °) in consideration of the opening / closing angle of the door of the automobile. As shown in the explanatory diagram of FIG. (Bending jig) It was sandwiched between 2 and 3 and repeatedly moved, and the other was suspended by a weight 4 of about 10 g. The repetition is performed under the condition of 3 Hz (3 repetitions per second), and when the wire specimen 1 breaks, the weight 4 falls and stops counting.

As is clear from Tables 1 and 2, Comparative Example 1 made of pure Al and Comparative Examples 2 to 6 having too little Fe content were inferior in bending fatigue resistance. Further, in Comparative Examples 7 to 11 in which the amount of Ti + V was too large, the conductivity was inferior. In Comparative Example 12, where the amount of Cu was too small, the bending fatigue resistance was inferior. In Comparative Example 13 where the amount of Cu was too large, the conductivity was inferior. In Comparative Example 14 where the amount of Mg was too small, the bending fatigue resistance was inferior. Even in Comparative Example 15 where the amount of Mg was too large, the bending fatigue resistance was inferior. In Comparative Example 16, where the amount of Si was too small, the bending fatigue resistance was inferior. Comparative Example 17 having too much Si was also inferior in bending fatigue resistance. In Comparative Example 18 in which the total amount of Cu, Mg, and Si was too small, the bending fatigue resistance was inferior. In Comparative Example 19 in which the particle size of the second phase was too large and the distribution density was too small, the bending fatigue resistance was inferior. In Comparative Example 20, a sample could not be prepared due to cracking.
In contrast, in Examples 1 to 22, the aluminum alloy wire material is excellent in bending fatigue resistance, excellent in tensile properties and conductivity, and suitable for use in wire harnesses used for doors, trunks, bonnets and the like of moving vehicle bodies. Met.

1 Test piece (wire)
2,3 Bending jig 4 Weight

Claims (4)

  0.1 to 0.4 mass% Fe, 0.1 to 0.3 mass% Cu, 0.02 to 0.2 mass% Mg, 0.02 to 0.2 mass% Si, In addition, it is an aluminum alloy wire comprising 0.001 to 0.01 mass% of Ti and V in combination, the balance Al and inevitable impurities, the crystal grain size in the vertical cross section in the wire drawing direction is 5 to 25 μm, and An aluminum alloy wire having a fatigue life of 50,000 times or more when subjected to repeated fatigue with a strain amplitude of ± 0.15% at room temperature.   Fe in an amount of 0.3 to 0.8 mass% and one or more elements selected from the group consisting of Cu, Mg, and Si in total of 0.02 to 1.0 mass%, and further, Ti and V Is an aluminum alloy wire comprising the balance Al and inevitable impurities, the crystal grain size in the vertical cross section in the wire drawing direction is 5 to 30 μm, and the strain amplitude at room temperature ± An aluminum alloy wire having a fatigue life of 50000 times or more when subjected to repeated fatigue of 0.15%. The tensile strength is 80 MPa or more, the electrical conductivity is 55% IACS or more, and the size of the second phase particles dispersed in the wire is 50 to 500 nm in terms of particle size, and the distribution density of the second phase particles is 1 to 10 ² / [mu] m ² a is claim 1 or 2, aluminum alloy wire according.   The aluminum alloy wire according to any one of claims 1 to 3, wherein the wire is used as a battery cable, a harness, or a motor conductor in a moving body.

Images