JP2012132073A - Conductive aluminum conductor material, aluminum electric wire and method for producing conductor for aluminum electric wire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide: a core wire for an aluminum electric wire, specifically suitable for an electric wire with a fine wire diameter, such as signal lines for automobiles, and having conductivity of 30% IACS or more and a tensile strength of 350 Pa or more; and a conductor for the aluminum electric wire.SOLUTION: A conductive aluminum conductor material includes 0.2-3 mass% of copper, 0.5-3.5 mass% of magnesium and 5-7.5 mass% of zinc, with the balance comprising aluminum and unavoidable impurities.

Description

  The present invention relates to a core wire for an aluminum electric wire that can be used for a signal line of an automobile, a conductive aluminum conductor material that enables such a core wire, and a method for manufacturing the core wire for an aluminum electric wire.

As a contribution to weight reduction of vehicles and reduction of environmental impact by improving fuel efficiency, it is possible to realize a thin wire having a core wire mainly made of a copper alloy, for example, a cross-sectional area of 0.13 mm ² or 0. There is a demand for a conductor applicable to the field of 35 mm ² electric wires.

  Here, since aluminum has a low conductivity, in order to pass the same current as copper, it is necessary to increase the conductor size (cross-sectional area) by 1.6 times, but the specific gravity is about 1/3 that of copper. Therefore, even when such a thick core wire is used, it is currently attracting attention because it is lighter than a conventional copper wire. Here, for example, when about 25 kg of aluminum conductors are substituted for all copper conductors in an automobile wire harness, a dramatic lightening effect of about 13 kg and about 50% can be obtained.

  However, assuming the replacement of a copper wire having a thin wire diameter level as described above, in a thin wire electric wire application used for a signal wire or the like of an automobile wire, the electrical conductivity is 30% IACS or more and the tensile strength is It is necessary to use a conductor of 350 Pa or higher.

  However, in the method proposed in Japanese Patent Application Laid-Open No. 2005-336549 (Patent Document 1) and the like, such a condition has not been achieved and has been a concern.

JP 2005-336549 A

  The present invention improves the above-mentioned conventional problems, that is, an aluminum electric wire having an electrical conductivity of 30% IACS or more and a tensile strength of 350 Pa or more, which is particularly suitable for a thin wire such as a signal wire for automobiles. It is an object of the present invention to provide a conductive aluminum conductor material for realizing the core wire and the aluminum wire conductor.

  In order to solve the above problems, the conductive aluminum conductor material of the present invention has a copper content of 0.2% by mass or more and 3% by mass or less, a magnesium content of 0.5% by mass or more and 3.5% by mass or less, as described in claim 1. And it contains 5 mass% or more and 7.5 mass% or less of zinc, and the remainder is comprised from aluminum and an unavoidable impurity, and is an aluminum conductor material for electroconductivity.

  The method for producing a conductor for an aluminum electric wire according to the present invention is a casting process for casting a rough drawn wire made of the conductive aluminum conductor material according to claim 1 at a temperature of 450 ° C to 500 ° C. Solution treatment process for solution treatment for not less than 10 hours but not more than 10 hours Cooling process for cooling at a cooling rate of 5 ° C./second or more, wire drawing process for drawing to a desired thickness, and 1 hour at 100 ° C. to 300 ° C. for 1 hour It is the manufacturing method of the conductor for aluminum electric wires provided with the aging treatment process which performs an aging treatment above for 50 hours or more in this order.

  As described in claim 3, the aluminum electric wire of the present invention is an aluminum electric wire comprising the aluminum electric wire conductor manufactured by the method for manufacturing an aluminum electric wire conductor according to claim 2. .

Furthermore, the aluminum electric wire of the present invention as described in claim 4, in an aluminum wire according to claim 3, the cross-sectional area of the conductor, characterized in that at 0.05 mm ² or more 2 mm ² or less.

  According to the conductive aluminum conductor material and the method for producing a conductor for an aluminum wire of the present invention, a conductor for an aluminum wire having an electrical conductivity of 30% IACS or higher and a tensile strength of 350 Pa or higher can be realized. Among the electric wires, it is possible to realize a lightweight electric wire that is particularly suitable for signal wire applications. At this time, it is possible to stretch 10% or more, and sufficient wire drawing workability and handleability as an electric wire used in a wire harness. can get.

  Since the aluminum electric wire of the present invention uses an aluminum electric wire conductor having an electrical conductivity of 30% IACS or higher and a tensile strength of 350 Pa or higher, it is particularly suitable for an electric wire for an automobile, particularly for a thin wire having a small diameter for use in a signal line. It is a conductor for aluminum electric wires.

FIG. 1 is a model diagram showing a cross section of a conductor for an aluminum electric wire according to the present invention manufactured in an example.

  In the conductive aluminum conductor material of the present invention, copper 0.2% by mass to 3% by mass, magnesium 0.5% by mass to 3.5% by mass, and zinc 5% by mass to 7.5% by mass. In addition, it is necessary that the balance is composed of aluminum and inevitable impurities. If these component ranges are not satisfied, sufficient tensile strength cannot be obtained when the wire core wire is formed.

  As for the content of inevitable impurities, silicon: 0.4 mass% or less, iron: 0.5 mass% or less, manganese: 0.3 mass% or less, chromium: 0.18 mass% to 0.28 mass%, titanium : 0.2% by mass or less, the sum of zircon and titanium is 0.25% by mass or less, and other components: 0.15% by mass or less.

  In the method for producing a conductor for an aluminum electric wire of the present invention, first, a rough drawn wire having the above composition is cast (a casting process). Casting can be performed by continuous casting, and rough drawing is performed by hot drawing. The thickness of the rough drawn wire can be freely selected, but in the case of a thin wire, the diameter is particularly preferably 0.1 mm or more and 1 mm or less.

  The rough drawn wire cast in such a casting process is subjected to a solution treatment (solution treatment process) at a temperature of 450 ° C. to 500 ° C. for 5 hours to 10 hours. Specifically, the coiled rough wire drawn is subjected to a solution treatment in a heating furnace (in the atmosphere).

  At this time, if the temperature is lower than 450 ° C., sufficient strength cannot be obtained, and if the temperature is higher than 500 ° C., sufficient strength cannot be obtained. Further, if the treatment time of the solution treatment step is less than 10 hours, sufficient strength cannot be obtained, and the effect of the present invention cannot be obtained.

  Here, the effect of the present invention can be obtained if the treatment time of the solution treatment is 10 hours or more, but even if the solution treatment is performed for a longer time beyond that, an effect commensurate with the long-time treatment is obtained. Therefore, the processing time is usually about 8 hours or less.

  After the solution treatment step, cooling is performed at a cooling rate of 5 ° C./second or more (cooling step). Such a cooling process can be realized by cooling in air.

  The rough drawn wire after the cooling step is drawn to a desired thickness using a wire drawing die or the like in the same manner as the copper electric wire (wire drawing step). Next, the drawn wire is subjected to an aging treatment at 100 ° C. or more and 300 ° C. or less for 1 hour or more and 50 hours or more using a heating furnace or the like (aging treatment step).

  If the aging treatment temperature is less than 100 ° C. or more than 300 ° C., sufficient strength cannot be obtained. Further, when the aging treatment is performed for a treatment time of less than 1 hour or over 50 hours, sufficient strength cannot be obtained. In this aging treatment step, continuous treatment wound in a coil shape or batch treatment is possible.

  By carrying out such a series of steps, an aluminum wire core wire having an electrical conductivity of 30% IACS or higher and a tensile strength of 350 Pa or higher is obtained, and if necessary, several wires are combined. Then, an insulating layer is formed by extrusion molding or the like from an olefin resin or a vinyl chloride resin as a conductor to obtain an insulated wire.

  The aluminum electric wire which concerns on this invention can be used suitably for a motor vehicle use, especially a thin wire diameter electric wire use, especially a signal wire.

  EXAMPLES Examples of the conductive aluminum conductor material of the present invention and the method for producing an aluminum electric wire conductor will be specifically described below.

  Copper, magnesium, and zinc were each blended with aluminum so as to have a blending amount (mass%) shown in Tables 1 to 3, and continuously cast to obtain a rough drawn wire having a diameter of 0.375 mm. In addition, inevitable impurities in aluminum and the abundance thereof were 0.01 to 0.05% by mass of silicon, and trace amounts of titanium, nickel, manganese, and zinc were detected by emission spectroscopic analysis.

These 22 types of roughing wires were subjected to a solution treatment in a heating furnace in air at 475 ° C. for 8 hours. Then, it was allowed to cool in air to cool to room temperature at a cooling rate of 5 ° C./second (however, in the example of Alloy No. 17, it was cooled to room temperature at a cooling rate of 20 ° C./second in water). After that, using a wire drawing die, the wire was drawn to a diameter of 0.375 mm, wound into a bobbin in a coil shape, and subjected to aging treatment at 200 ° C. for 30 hours in air in a heating furnace to obtain a core wire. Then, seven core wires were twisted to form a conductor for an aluminum electric wire having a cross section (see FIG. 1) of 1.5 mm ² .

  The 26 types of conductors for aluminum electric wires thus obtained were measured for electrical conductivity (% IACS) and tensile strength according to JIS C3002. The results are also shown in Tables 1 to 3.

  From Tables 1 to 3, it can be seen that the conductor for an aluminum electric wire according to the present invention has a conductivity of 30% IACS or more and a tensile strength of 350 Pa or more.

1 Conductor for aluminum wire 1a Core wire for aluminum wire

Claims (4)

  Contains 0.2% to 3% by weight of copper, 0.5% to 3.5% by weight of magnesium, and 5% to 7.5% by weight of zinc, with the balance being aluminum and inevitable impurities A conductive aluminum conductor material characterized by comprising:   A casting process for casting a rough drawn wire comprising the conductive aluminum conductor material according to claim 1, a solution treatment process for solution treatment at a temperature of 450 ° C to 500 ° C for 5 hours to 10 hours, 5 ° C / second or more A cooling step of cooling at a cooling rate of 1, a drawing step of drawing to a desired thickness, and an aging treatment step of performing an aging treatment at 100 to 300 ° C. for 1 to 50 hours in this order. A method for producing a conductor for an aluminum electric wire.   An aluminum electric wire comprising the aluminum electric wire conductor manufactured by the method for manufacturing an aluminum electric wire conductor according to claim 2. The aluminum electric wire according to claim 3, wherein a cross-sectional area for the aluminum electric wire is 0.05 mm ² or more and 2 mm ² or less.

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