JP5469262B2 - Aluminum alloy conductor and method for producing the same - Google Patents

Description

  The present invention relates to an aluminum alloy conductor used as a conductor of an electric wiring body and a manufacturing method thereof.

2. Description of the Related Art Conventionally, a member in which a terminal (connector) made of copper or copper alloy (for example, brass) is mounted on 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, or 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 mass is still about half that of copper. Therefore, there is an advantage.
In addition, said% IACS expresses the electrical conductivity when the resistivity 1.7241 × 10 ⁻⁸ Ωm of universal standard annealed copper (International Annealed Copper Standard) is 100% IACS.

There are some problems in using the aluminum as a conductor of an electric wiring body of a moving body, and one of them is improvement in bending fatigue resistance. The reason why the aluminum conductor used for the electric wiring body of the moving body is required to have bending fatigue resistance is that the wire harness attached to the door or the like is repeatedly subjected to bending stress by opening and closing the door. When a metal material such as aluminum is repeatedly applied and removed such as opening and closing of a door even at a low load that does not break at a single load, fatigue failure that breaks at a certain number of repetitions occurs. When the aluminum conductor is used for an opening / closing portion, if the bending fatigue resistance is poor, there is a concern that the conductor may break during use, resulting in a problem of lack of durability and reliability.
Generally, it is said that a material having higher strength has better fatigue characteristics. Therefore, high-strength aluminum wire may be applied, but the wire harness is required to be easy to handle (installation work on the vehicle body) at the time of installation, and generally has an elongation of 10% or more. In many cases, a dull material (annealed material) that can be secured is used.

  Therefore, the aluminum conductor used for the electric wiring body of the moving body is a material having excellent bending fatigue resistance in addition to the strength required for handling and mounting, and the conductivity necessary for flowing a large amount of electricity. Is required.

  For such demanding applications, pure aluminum systems such as power transmission line aluminum alloy wires (JIS A1060 and JIS A1070) cannot sufficiently withstand repeated bending stresses that occur when doors are opened and closed. In addition, although alloyed materials with various additive elements are excellent in strength, they cause a decrease in conductivity due to a solid solution phenomenon of the additive elements in aluminum, and form excessive intermetallic compounds in aluminum. Therefore, there is a problem that wire breakage may be caused during wire drawing. Therefore, it is necessary to limit and select additive elements to prevent the decrease in conductivity and workability, and to improve the strength and the bending fatigue resistance.

Typical examples of the aluminum conductor used for the electric wiring body of the moving body include those described in Patent Documents 1 to 3. However, as described below, the inventions described in any of the patent documents have further problems to be solved.
The electric wire conductor described in Patent Document 1 has an excessively high tensile strength, and it may be difficult to perform the attachment work to the vehicle body.
The aluminum conductive wire specifically described in Patent Document 2 is not subjected to finish annealing. Moreover, since Cu is not contained, the elongation is low, and a higher flexibility is required for the mounting work on the vehicle body.
Patent Document 3 discloses an aluminum conductive wire that is lightweight, flexible, and excellent in bendability. However, there is an increasing demand for improving the characteristics of an electric wiring body of a moving body, and further improvement of characteristics is desired. Yes.

JP 2008-112620 A JP 2006-19163 A JP 2006-253109 A

The present invention provides an aluminum alloy conductor excellent in bending fatigue resistance , tensile strength (also referred to simply as strength in this document), tensile elongation at break (also referred to as elongation in this document), and a method for producing the same. Is an issue.

The present inventors have made various studies, satisfying the required bending fatigue resistance , tensile strength and tensile elongation at break, the components contained in the aluminum alloy conductor, as well as the casting cooling rate and finish annealing conditions of the conductor. By controlling the manufacturing process, etc., it was found that the characteristics can be improved by optimizing the crystal grain size of the conductor by utilizing the effect of the additive element, and the present invention has been completed based on this finding. It came to do.

That is, the present invention provides the following solutions.
(1) Cu contains 0.1 to 1 mass% and at least one element selected from the group consisting of Sn, Cd and In in a total amount of 0.01 to 0.5 mass%, from the remaining Al and inevitable impurities An aluminum alloy conductor having a tensile elongation at break of 10% or more , a tensile strength of 120 MPa or more, and a repeated number of breaks of 90000 or more .
(2) 0.1 to 1 mass% of Cu and 0.01 to 0.5 mass% in total of at least one element selected from the group consisting of Sn, Cd and In, and Fe0.01 mass% to 1 0.0 mass% and Mg 0.1 to 0.35 mass%, further containing Zr 0.001 to 0.1 mass%, the balance being Al and inevitable impurities, tensile elongation at break 10% or more , tensile An aluminum alloy conductor having a strength of 120 MPa or more and a repeated breaking number of 90000 times or more .
(3) An aluminum alloy conductor containing 0.001 to 0.1 mass% of Zr in addition to the aluminum alloy conductor according to (1).
(4) The mass ratio of the total content (W1) of at least one element selected from the group consisting of Sn, Cd, and In to the content (W2) of Zr is 0.6 to 2.6. The aluminum alloy conductor according to item (2) or (3).
(5) The aluminum alloy conductor according to any one of (1) to (4), wherein the conductor is used as a battery cable, a harness, or a motor wire in a moving body.
(6) The aluminum alloy conductor according to any one of (1) to (5), wherein the conductor is used in a vehicle, a train, or an aircraft.
(7) After melting the aluminum alloy component that gives the aluminum alloy composition according to any one of (1) to (4), continuous casting and rolling are performed to obtain a rough bar, and then cold drawn to rough drawn wire The method of manufacturing the aluminum alloy conductor according to any one of (1) to (4), further comprising a step of performing a heat treatment, performing a wire drawing process to obtain a wire, and further performing an annealing heat treatment. Then, the continuous casting and rolling is performed under the condition of a casting cooling rate of 1 to 20 ° C./second, and the cold drawing is performed with the wire cross-sectional area before processing as A ₀ and the wire cross-sectional area after processing as A _1. , Η = ln (A ₀ / A ₁ ), the degree of processing is 1 to 6 and the heat treatment is performed at a temperature of 300 to 450 ° C. for 10 minutes to 6 hours. Processing is performed at a processing degree of 1 to 6 and a drawing speed of 500 to 2000 m. The annealing heat treatment is a continuous heat treatment including rapid heating and rapid cooling steps, and is performed by performing either <1> or <2> below. Production method:
<1> Wire temperature y (° C.) and annealing time x (seconds)
0.03 ≦ x ≦ 0.55, and ^{26x -0.6 + 377 ≦ y ≦ 23.5x} -0.6 +423
Continuous energization heat treatment satisfying the relationship: or <2> annealing furnace temperature z (° C.) and annealing time x (seconds),
1.5 ≦ x ≦ 5, and −50x + 550 ≦ z ≦ −36x + 650
Continuous running heat treatment that satisfies the relationship.

The aluminum alloy conductor of the present invention has excellent tensile elongation at break, tensile strength, bending fatigue resistance (predetermined number of repeated fractures) and electrical conductivity, and is useful as a battery cable, harness or motor conductor mounted on a moving body. It can also be suitably used for doors, trunks, bonnets and the like that require excellent bending fatigue resistance.
Furthermore, the aluminum alloy conductor of the present invention is excellent in that the bending fatigue characteristics do not deteriorate even when exposed to a high temperature (for example, 120 ° C.), and is excellent in corrosion resistance.

  The above and other features and advantages of the present invention will become more apparent from the following description, with reference where appropriate to the accompanying drawings.

FIG. 1 is an explanatory diagram of a repeated fracture number test of an example.

Next, the present invention will be described.
The present invention contains 0.1 to 1 mass% of Cu and 0.01 to 0.5 mass% in total of at least one element selected from the group consisting of Sn, Cd and In, with the balance being Al and inevitable impurities An aluminum alloy conductor made of Here, inevitable impurities in the alloy composition of this aluminum alloy conductor are disclosed in JISH2110 (aluminum alloy base metal for electrical use), Fe0.25 mass% or less, Si0.1 mass% or less, Cu0.005 mass% or less, Mn0 0.005 mass% or less and Ti + V 0.005 mass% or less.
Moreover, inevitable impurities in bullion actually produced industrially are generally in the range of 0.05 to 0.15 mass% of Fe and 0.04 to 0.1 mass% of Si. In addition, although Fe and Si content less than 0.01 mass% is generally handled as high-purity aluminum, high-purity aluminum itself is included in this preferable range because the Fe and Si content is low. Absent.
The alloy composition of the aluminum alloy conductor may contain Mg 0.1 to 0.35 mass%. Fe may be contained in an amount of 1.0 mass% or less exceeding the content of the inevitable impurities.

In order to improve the bending fatigue resistance, Cu does not form second phase particles, but is in a solid solution state in aluminum. However, Cu easily forms Al and second-phase particles, and the amount of the second-phase particles increases as the amount of Cu added increases, and the formed second-phase particles deteriorate in bending fatigue characteristics. Bring.
The reason why Cu is 0.1 to 1 mass% is that when it is less than 0.1 mass%, the amount of solid solution is small and the bending fatigue resistance is not good, and when it is 1 mass% or more, the following specific manufacturing method is used. However, the formation of second phase particles of Cu and Al cannot be prevented, the corrosivity mediated by the particles becomes remarkable and the corrosion resistance is inferior, and the bending fatigue resistance is lowered by the particles. Because there is.
By the way, Sn, Cd, and In have a function of capturing vacancies in the aluminum alloy, that is, have a function of suppressing or delaying the diffusion action that proceeds along with the vacancies, thereby causing Al and Generation of second phase particles containing Cu as a component is suppressed. As a result, the bending fatigue resistance can be further improved by adding at least one element selected from the group consisting of Sn, Cd and In.
The content of at least one element selected from the group consisting of Sn, Cd, and In is 0.01 to 0.5 mass% in total. If it is less than 0.01 mass%, the effect of inhibiting the generation of second phase particles If the amount exceeds 0.5 mass%, the effect of inhibiting the generation is saturated and the elongation is lowered. If the total amount is too large, cracks are likely to occur during wire drawing, and industrial production cannot be realized. It is.

  However, the effect of suppressing the formation of second phase particles by the addition of at least one element selected from the group consisting of Sn, Cd and In is remarkable at a low temperature of 100 ° C. or lower, but at a high temperature exceeding 100 ° C. The higher the temperature is, the less effective the suppression is and the generation of precipitated particles may occur. Therefore, the phenomenon that the precipitation suppressing effect disappears can be canceled by further adding Zr. When Zr is added together with at least one element selected from the group consisting of Sn, Cd and In, the effect of suppressing the generation of second phase particles containing Al and Cu as components even at a high temperature exceeding 100 ° C. Have. If the amount of Zr added is 0.001 to 0.1 mass%, the effect is insufficient if it is less than 0.001 mass%, and if it exceeds 0.1 mass%, Al-Zr-based second phase particles. This is because the generation amount of is increased to reduce the bending fatigue resistance.

  In the mass ratio (W1 / W2) of the total content (W1) of at least one element selected from the group consisting of Sn, Cd, and In and the content (W2) of Zr (W1 / W2), a more preferable range is 0.6. ~ 2.6. In this range, even at a high temperature exceeding 100 ° C., it has an effect of further suppressing the generation of second phase particles containing Al and Cu as components.

  According to the aluminum alloy conductor of the present invention, an aluminum alloy conductor having desired excellent bending fatigue resistance, strength, and conductivity can be obtained by strictly controlling the manufacturing method in addition to the above components. .

(Tensile strength)
The tensile strength of the aluminum alloy conductor of the present invention is 120 MPa or more. This is because if the tensile strength is less than 120 MPa, the strength is insufficient including handling, and it is difficult to use as an industrial conductor. The tensile strength is preferably 120 to 160 MPa, more preferably 120 to 150 MPa.

(conductivity)
The electrical conductivity of the aluminum alloy conductor of the present invention is 52% IACS or higher. Originally, when the electrical conductivity is less than 57% IACS, a high current of several tens of A (amperes) flows when used for a power line, and there is a concern that current loss becomes severe. Therefore, it is preferably 57 to 62% IACS conductivity. is there. However, for example, when applied to a communication line such as a battery cable or a wire harness in a moving body, the range is not limited to 57% IACS or more, and may be 52% IACS or more.

(Bending fatigue resistance)
The aluminum alloy conductor of the present invention has excellent bending fatigue resistance. The test is performed with a strain amplitude of ± 0.17% as a standard of the bending fatigue resistance. Bending fatigue resistance varies with strain amplitude. When the strain amplitude is large, the fatigue life is shortened, and when the strain amplitude is small, the fatigue life is lengthened. Since the strain amplitude can be determined by the wire diameter of the wire rod (aluminum alloy conductor) 1 shown in FIG. 1 and the curvature radii of the bending jigs 2 and 3, the wire diameter of the wire rod 1 and the curvature radii of the bending jigs 2 and 3 are arbitrary. It is possible to perform a bending fatigue test by setting to.
Next, assuming that the number of times of opening and closing per day is 10 and the use for 20 years is assumed, the number of times of opening and closing is 73,000 (calculated as 365 days a year). The actually used electric wire is not a single wire but has a stranded wire structure, and since the coating process is performed, the burden on the electric wire conductor becomes a fraction. The number of repeated fractures of 90000 times or more that can ensure sufficient bending fatigue resistance as an evaluation value for a single wire is the required level. Good Mashiku is at least 100000, further preferably at least 150,000 times. In automobile applications, electric wires may be exposed to high temperatures under harsh usage environments. In general, when 10 years of use is assumed, an accelerated test is applied in which exposure is performed at a high temperature of 120 ° C. for 120 hours. Therefore, 120 ° C., even after standing for 120 hours, it is demanding be repeated breaking number of more than 9 0000 times.

(Production method)
Next, the manufacturing method of the aluminum alloy conductor of this invention is demonstrated.
The aluminum alloy conductor of the present invention includes [1] melting, [2] casting, [3] hot or cold working (groove roll processing, etc.), [4] wire drawing, [5] heat treatment (intermediate annealing), It can be manufactured under predetermined manufacturing conditions through each step of [6] wire drawing and [7] heat treatment (finish annealing).

  In the melting, the alloy components having the above-mentioned aluminum alloy composition are melted in amounts so as to be the concentrations of the respective embodiments.

  Next, rolling is performed while continuously casting the molten metal in a water-cooled mold using a Properti-type continuous casting and rolling machine in which a casting wheel and a belt are combined to obtain a rough bar having a diameter of about 10 mm. The casting cooling rate at this time is 1 to 20 ° C./second. Casting and hot rolling may be performed by billet casting, extrusion, or the like.

Next, the surface is peeled to 9 to 9.5 mmφ, which is drawn to obtain a rough drawn wire. The degree of processing is 1 or more and 6 or less. Here working ratio eta is a wire sectional area before drawing A _0, when the wire cross-sectional area after drawing and A _1, represented by _{η = ln (A 0 / A} 1). If the degree of work at this time is too small, the recrystallized grains become coarse during the heat treatment in the next step, and the strength and elongation are remarkably lowered, which may cause disconnection. If it is too large, the wire drawing process becomes difficult, and there may be a problem in terms of quality such as disconnection during the wire drawing process. Although the surface is cleaned by carrying out the peeling of the surface, it may not be carried out.

  Intermediate annealing is performed on the cold drawn wire. The intermediate annealing is performed mainly to regain the flexibility of the wire that has been hardened by wire drawing. If the intermediate annealing temperature is too high or too low, the wire is broken in the subsequent wire drawing process, and the wire cannot be obtained. The intermediate annealing temperature is 300 to 450 ° C, preferably 350 to 450 ° C. The time for the intermediate annealing is 10 minutes or more and 6 hours or less. If it is less than 10 minutes, the time required for the formation and growth of recrystallized grains is insufficient, and the flexibility of the wire cannot be recovered. Preferably it is 1 to 6 hours. The average cooling rate from the heat treatment temperature during intermediate annealing to 100 ° C. is not particularly specified, but is preferably 0.1 to 10 ° C./min.

  Further, wire drawing is performed to obtain a wire. In order to obtain the recrystallized texture as described above, the degree of processing (degree of processing before continuous heat treatment) at this time is set to 1 or more and 6 or less. The degree of work greatly affects the formation and growth of recrystallized grains. If the degree of work is too small, the recrystallized grains become coarse during the heat treatment in the next step, and the strength and elongation are significantly reduced, which may cause disconnection. Further, there are cases where the driving force for moving the recrystallized grain boundary is insufficient and the desired recrystallized texture cannot be formed. If it is too large, the wire drawing process becomes difficult, and there may be a problem in terms of quality such as disconnection during the wire drawing process. The degree of processing is preferably 2 or more and 6 or less.

  The wire drawing speed is controlled in order to obtain a desired recrystallization texture. The drawing speed is 500 to 2000 m / min. If the drawing speed is less than 500 m / min, the target recrystallized texture may not be obtained at the time of final annealing in the next step. When the drawing speed exceeds 2000 m / min, the frictional force applied to the wire is large, and the target recrystallized texture may not be obtained during the final annealing of the next process, and the wire is broken during the drawing process. May cause problems in terms of quality. The drawing speed is preferably 800 to 1800 m / min.

A cold-drawn wire having a predetermined wire diameter is subjected to finish annealing by batch heat treatment or continuous heat treatment to obtain an aluminum alloy conductor.
The conditions for batch heat treatment as finish annealing are as follows.
As for the conditions of the finish annealing by the batch type annealing furnace, the temperature is 300 to 450 ° C. This is because when the temperature is lower than 300 ° C., non-recrystallized grains remain and sufficient flexibility cannot be secured. Moreover, when it exceeds 450 degreeC, a coarse recrystallized grain will be formed and tensile strength and elongation will fall remarkably. The time is 10 minutes to 6 hours. If it is less than 10 minutes, unrecrystallized grains remain and sufficient flexibility cannot be secured. Further, if it exceeds 6 hours, coarse recrystallized grains are formed depending on the heat treatment temperature, and the tensile strength and elongation are remarkably lowered. From the viewpoint of productivity, it is not good if it exceeds 6 hours. The conditions for finish annealing are preferably 300 to 450 ° C. and 30 minutes to 4 hours.
Of the finish annealing, the continuous heat treatment can be performed by one of two methods: continuous energization heat treatment and continuous running heat treatment.

The continuous energization heat treatment is performed by annealing with Joule heat generated from itself by passing an electric current through a wire passing through two electrode wheels. It includes the steps of rapid heating and quenching, and the wire can be annealed by controlling the wire temperature and annealing time. Cooling is performed by passing the wire continuously in water or a nitrogen gas atmosphere after rapid heating. If one or both of the wire temperature is too low and / or the annealing time is too short, the required flexibility for on-vehicle installation etc. will not be obtained, while the wire temperature is too high or the annealing time is too long In one or both of these cases, the crystal orientation is excessively rotated by over-annealing, the desired recrystallized texture cannot be obtained, and the bending fatigue resistance property is also deteriorated. Therefore, if it carries out on the conditions which satisfy | fill the following relationships, it can be set as said desired recrystallization texture.
In continuous energization heat treatment, if the wire temperature is y (° C.) and the annealing time is x (seconds),
0.03 ≦ x ≦ 0.55, and ^{26x -0.6 + 377 ≦ y ≦ 23.5x} -0.6 +423
To meet.
The wire temperature y (° C.) represents the temperature immediately before passing through the cooling step, at which the temperature of the wire becomes the highest. y (° C.) is usually in the range of 414 to 616 (° C.).

In the continuous running heat treatment, the wire is continuously passed through an annealing furnace kept at a high temperature and annealed. It includes the steps of rapid heating and rapid cooling, and the wire can be annealed under the control of the annealing furnace temperature and annealing time. Cooling is performed by passing the wire continuously in water or a nitrogen gas atmosphere after rapid heating. If one or both of the annealing furnace temperature is too low or the annealing time is too short, the necessary flexibility for on-vehicle installation etc. will not be obtained, while the annealing furnace temperature is too high or the annealing time is long. In the case of one or both of them, the crystal orientation is excessively rotated by over-annealing, the desired recrystallized texture cannot be obtained, and the bending fatigue resistance property is also deteriorated. Therefore, if it carries out on the conditions which satisfy | fill the following relationships, it can be set as said desired recrystallization texture.
In continuous running heat treatment, if the annealing furnace temperature is z (° C.) and the annealing time is x (seconds),
1.5 ≦ x ≦ 5, and −50x + 550 ≦ z ≦ −36x + 650
To meet.
The annealing furnace temperature z (° C.) represents the temperature immediately before passing through the cooling step, at which the temperature becomes the highest as a wire. z (° C.) is usually in the range of 300 to 596 (° C.).
In addition to the above two methods, the finish annealing by continuous heat treatment may be induction heating in which a wire continuously passes through a magnetic field and is annealed.

  As described in detail above, the aluminum alloy conductor of the present invention produced by appropriately performing heat treatment has a recrystallized structure in addition to having the predetermined alloy composition. The recrystallized structure is a structure state composed of crystal grains with few lattice defects such as dislocations introduced by plastic working. By having a recrystallized structure, tensile elongation at break and electrical conductivity are recovered, and sufficient flexibility can be obtained.

  The invention is explained in more detail on the basis of the following examples. In addition, this invention is not limited to the Example shown below.

Example No. 201-212, Comparative Example No. 213-218
As shown in Table 1 described later, each component was used in a predetermined amount ratio (mass%) to obtain an alloy. Here, about Al, it was JIS-H4040 alloy number 1070 and content of an inevitable impurity shall not exceed the value of Table 1.
This alloy was rolled using a Properti type continuous casting and rolling machine while continuously casting it in a mold in which the molten metal was cooled with water to obtain a rough bar having a diameter of about 10 mm. The casting cooling rate at this time was 1 to 20 ° C./second.
Next, the surface was peeled to 9 to 9.5 mmφ, which was drawn to obtain a 2.6 mmφ rough drawn wire. Next, as shown in Table 1, this cold-drawn workpiece was subjected to intermediate annealing at a temperature of 300 to 450 ° C. for 0.5 to 4 hours.
In this example, the wire drawing speed was 1500 m / min, the workability η was 2.1, and the final wire diameter was 0.31 mm. Moreover, as shown in Table 1, the heat treatment as finish annealing was performed under the conditions described in Table 1 by continuous energization heat treatment or batch heat treatment.
In this way, an aluminum alloy conductor was prepared.
About the produced aluminum alloy conductor of each Example and a comparative example, each characteristic was measured as follows.

(B) Tensile strength (TS) and flexibility (tensile elongation at break, El)
Three each were tested according to JIS Z 2241 and the average value was determined. The flexibility was evaluated using the tensile elongation at break, and the tensile elongation at break was 10% or more.
(C) Conductivity (EC)
Three specific resistances were measured using a four-terminal method in a constant temperature bath holding a 300 mm long test piece at 20 ° C. (± 0.5 ° C.), and the average conductivity was calculated. The distance between the terminals was 200 mm.
(D) Number of repeated fractures Using a double-bending bending fatigue testing machine manufactured by Fujii Seiki Co., Ltd. (currently Fujii Co., Ltd.), a jig that gives a bending strain of ± 0.17% to the wire (aluminum alloy conductor) is used. Then, the number of repeated fractures was measured by repeatedly bending. The number of repeated ruptures was measured four by four and the average value was determined. As shown in the explanatory view of FIG. 1, the wire 1 was inserted with a gap of 1 mm between the bending jigs 2 and 3, and repeatedly moved in such a manner as to be along the jigs 2 and 3. One end of the wire was fixed to a holding jig 5 so that it could be bent repeatedly, and a weight 4 of about 10 g was hung from the other end. Since the holding jig 5 moves during the test, the wire 1 fixed to the holding jig 5 also moves and can be bent repeatedly. The repetition is performed under the condition of 1.5 Hz (1.5 reciprocations per second), and when the wire specimen 1 breaks, the weight 4 falls and stops counting.
Further, the number of repeated breaks was also measured for the characteristics after being left at 120 ° C. for 120 hours.

Further, in addition to these tests, a salt spray test was performed on the electric wire (aluminum alloy conductor). The produced aluminum alloy conductor was cut into a length of about 1 m and exposed to a neutral 5% salt spray test (JISH8502) for 96 hours. When the cross section of the sample after the test is filled with resin and observed with an optical microscope, pitting corrosion having a length of 1/5 or more of the wire diameter or depth from the surface of the aluminum alloy conductor is observed on the surface of the aluminum alloy conductor. When the aspect of intergranular corrosion was detected to a depth of 1/5 or more of the wire diameter in the direction, it was determined as x. On the other hand, even if there was pitting corrosion or intergranular corrosion, the length was 1/5. Those less than were judged as ◯, and those hardly seen were judged as ◎.
The results are shown in Table 1.

表１より、Ｎｏ．２０１〜２１２のＳｎ、Ｃｄ、Ｉｎ、Ｚｒを含有するアルミニウム合金導体における、繰り返し破断回数は、いずれも１０万回を超えており、優れた屈曲特性であることが分かり、また、１２０℃放置後においても破断回数の低下はわずかであり、繰り返し破断回数は９万５千回を超えた。また、引張強度、引張破断伸び、耐食性（円錐噴霧試験での評価）も良好であった。
これに対し、Ｃｕ添加の少なすぎたＮｏ．２１３、２１４のアルミニウム合金導体は、引張強度が不足し、繰り返し破断回数が９万回を大きく下回り、さらに１２０℃放置後に低下が顕著であった。また、Ｃｕ過剰のＮｏ．２１５、２１６のアルミニウム合金導体は、１２０℃放置後の繰り返し破断回数低下が顕著であるとともに、塩水噴霧試験における劣化が悪かった。さらに比較例Ｎｏ．２１５のアルミニウム合金導体では引張破断伸びも不足し、比較例Ｎｏ．２１６のアルミニウム合金導体では繰り返し破断回数も不足する。また、比較例Ｎｏ．２１７、２１８のアルミニウム合金導体は、どちらも引張破断伸びが本発明の規定を満たさずに劣り、さらに比較例Ｎｏ．２１８のアルミニウム合金導体では引張強度及び繰り返し破断回数も不足する。これらの比較例Ｎｏ．２１７、２１８は、製造条件が本発明の規定範囲外となる例である。

From Table 1, No. In the aluminum alloy conductor containing Sn, Cd, In, and Zr of 201 to 212, the number of repeated breaks exceeds 100,000, and it is found that the bending property is excellent, and after leaving at 120 ° C. Also, the decrease in the number of breaks was slight, and the number of repeated breaks exceeded 95,000. Further, the tensile strength, the tensile elongation at break, and the corrosion resistance (evaluation in a cone spray test) were also good.
On the other hand, No. with too little Cu addition. The aluminum alloy conductors Nos. 213 and 214 had insufficient tensile strength, the number of repeated breaks was significantly less than 90,000, and the decrease was remarkable after standing at 120 ° C. Further, Cu-excess No. The aluminum alloy conductors Nos. 215 and 216 had a remarkable decrease in the number of repeated breaks after standing at 120 ° C., and the deterioration in the salt spray test was bad. Further, Comparative Example No. The aluminum alloy conductor of 215 also lacks tensile elongation at break. 216 aluminum alloy conductors also lack the number of repeated breaks. Comparative Example No. The aluminum alloy conductors Nos. 217 and 218 are both inferior in tensile elongation at break not satisfying the provisions of the present invention. In 218 aluminum alloy conductor of insufficient tensile strength and return Shi breaking number Ri Repetitive. These Comparative Examples No. Reference numerals 217 and 218 are examples in which the manufacturing conditions are outside the specified range of the present invention.

  While this invention has been described in conjunction with its embodiments, we do not intend to limit our invention in any detail of the description unless otherwise specified and are contrary to the spirit and scope of the invention as set forth in the appended claims. I think it should be interpreted widely.

  This application claims the priority based on Japanese Patent Application No. 2010-163416 for which it applied for a patent in Japan on July 20, 2010, and this is referred to here for the contents of this description. Capture as part.

1 Test piece (wire, aluminum alloy conductor)
2, 3 Bending jig 4 Weight 5 Holding jig

Claims (7)

It contains 0.1 to 1 mass% of Cu and 0.01 to 0.5 mass% in total of at least one element selected from the group consisting of Sn, Cd and In, and is composed of the balance Al and inevitable impurities, An aluminum alloy conductor having a breaking elongation of 10% or more , a tensile strength of 120 MPa or more, and a repeated breaking number of 90000 times or more .
It contains 0.1 to 1 mass% of Cu and 0.01 to 0.5 mass% in total of at least one element selected from the group consisting of Sn, Cd and In, and Fe 0.01 mass% to 1.0 mass% And Mg 0.1 to 0.35 mass%, further containing Zr 0.001 to 0.1 mass%, the balance consisting of Al and inevitable impurities, tensile elongation at break of 10% or more , and tensile strength of 120 MPa. An aluminum alloy conductor having a number of repeated breaks of 90000 times or more .
  The aluminum alloy conductor according to claim 1, further comprising 0.001 to 0.1 mass% of Zr.   The mass ratio of the total content (W1) of at least one element selected from the group consisting of Sn, Cd and In to the content (W2) of Zr is 0.6 to 2.6. The aluminum alloy conductor according to claim 2 or 3.   The aluminum alloy conductor according to any one of claims 1 to 4, wherein the conductor is used as a battery cable, a harness, or a wire for a motor in a moving body.   The aluminum alloy conductor according to any one of claims 1 to 5, wherein the conductor is used in a vehicle, a train, or an aircraft. The aluminum alloy component that gives the aluminum alloy composition according to any one of claims 1 to 4 is melted, then subjected to continuous casting and rolling to form a rough bar, cold drawn to a rough drawn wire, and subjected to heat treatment. The method for producing an aluminum alloy conductor according to any one of claims 1 to 4, further comprising a step of performing wire drawing to obtain a wire, and further performing an annealing heat treatment. carried out under the conditions of the casting cooling rate is 1 to 20 ° C. / sec, the cold wire drawing, the wire cross-sectional area before processing a _0, the wire cross-sectional area after working as _{a 1, η = ln (a} 0 / A ₁ ) is performed under the condition of a workability represented by 1 or more and 6 or less, the heat treatment is performed at a temperature of 300 to 450 ° C. for 10 minutes to 6 hours, and the wire drawing is performed with a workability of 1 More than 6 and the drawing speed is 500 to 2000 m / min. Performed, the annealing heat treatment, rapid heating, a continuous heat treatment comprising rapid cooling step, the following <1> or <2> aluminum alloy conductor fabrication method, which comprises carrying out by applying one of:
<1> Wire temperature y (° C.) and annealing time x (seconds)
0.03 ≦ x ≦ 0.55, and ^{26x -0.6 + 377 ≦ y ≦ 23.5x} -0.6 +423
Continuous energization heat treatment satisfying the relationship: or <2> annealing furnace temperature z (° C.) and annealing time x (seconds),
1.5 ≦ x ≦ 5, and −50x + 550 ≦ z ≦ −36x + 650
Continuous running heat treatment that satisfies the relationship.

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