JP5365998B2 - Electric wire with terminal and terminal member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric wire with a terminal superior in corrosion resistance, and a terminal member suitable as a component member for the electric wire with the terminal. <P>SOLUTION: The electric wire with the terminal 1 includes an electric wire 10 made of an aluminum alloy conductor 11 covered with an insulating layer 12 around its periphery, and the terminal member 20 made of copper or a copper alloy and attached to an exposed region exposed by elimination of the insulating layer 12 on the conductor 11 at an end part of the electric wire 10. Of the terminal member 20, a contactless region is covered with an insulation coating except for the contact region with the exposed part of the conductor 11 and a contact region with an external terminal. The electric wire with the terminal 1 is superior in corrosion resistance, since at least a portion of the contactless region of the terminal member 20 is insulation coated, resulting in reduction of formation of an electric cell between the aluminum alloy constituting the conductor 11 and the copper or the copper alloy constituting the terminal member 20. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to an electric wire with a terminal including an electric wire having a conductor made of an aluminum alloy and a terminal member made of copper or a copper alloy, and a terminal member. In particular, the present invention relates to an electric wire with a terminal excellent in corrosion resistance.

  Conventionally, electric wires of transport equipment such as automobiles and airplanes, and industrial equipment such as robots are used in a state where the conductor is exposed by removing the insulating layer at the end and a terminal is attached to the exposed portion of the conductor. . Moreover, the wire harness which the terminal was attached to the edge part of several electric wires and was bundled is also utilized. The constituent materials of the conductors and terminals of the electric wires are mainly copper-based materials such as copper and copper alloys having excellent conductivity.

  In recent years, the performance and functionality of automobiles have been rapidly increased, and with the increase of various electric devices and control devices mounted on the vehicle, the number of electric wires used for these devices is also increasing. On the other hand, in recent years, in order to preserve the environment, it is desired to improve the fuel consumption of automobiles and aircraft. When the weight is reduced, fuel consumption can be improved. Therefore, in order to reduce the weight of the electric wire, use of aluminum having a specific gravity of about 1/3 of copper or an alloy thereof as a conductor has been studied (Patent Document 1).

Japanese Patent Laid-Open No. 2003-243058

  When the conductor is made of an aluminum alloy and the terminal is made of copper or a copper alloy, that is, when the constituent material of the conductor and the constituent material of the terminal are different metals, the conductor made of the aluminum alloy and the terminal made of copper, etc. A battery is formed between them, and the aluminum alloy is corroded. Therefore, it is desired to improve corrosion resistance for a terminal-attached electric wire having a conductor made of an aluminum alloy and a terminal made of copper or a copper alloy.

  Then, the objective of this invention is providing the electric wire with a terminal which is excellent in corrosion resistance. Moreover, the other object of this invention is to provide the terminal member suitable for the component of the said electric wire with a terminal.

  The present inventors examined the corrosion state of the conductor by attaching a terminal made of copper or a copper alloy to an electric wire made of an aluminum alloy. As a result, the part covered by the terminal in the exposed part of the conductor where the insulating layer is peeled off and the conductor is exposed is difficult to corrode because it is difficult to contact the atmosphere (especially dissolved oxygen of moisture in the atmosphere), A portion of the exposed conductor that was not covered with the terminal (hereinafter referred to as a fully exposed portion) was easily corroded. This is due to the exception of contact points that come into contact with exposed parts of conductors and contact points where external terminals (if the terminal is a female terminal: male terminal, if the terminal is a male terminal: female terminal). This is considered to be because a battery is formed between the region (hereinafter referred to as a non-contact region) and the completely exposed portion. In order to reduce the formation of this battery, it is effective to cover the non-contact region of the terminal with an insulating material. The present invention is based on the above findings.

  The electric wire with terminal of the present invention is an electric wire in which the outer periphery of a conductor made of an aluminum alloy is covered with an insulating layer, and a terminal attached to an exposed portion exposed by removing the insulating layer in the conductor at the end of the electric wire With a member. The terminal member is made of copper or a copper alloy. In this terminal member, at least a part of the non-contact area except for the contact portion with the exposed portion of the conductor and the contact portion with the external terminal is covered with an insulating coating. In particular, the area of the exposed portion of the conductor is Sd, the area of the uncovered portion of the terminal member that is not covered by the insulating coating is Sc, and the area of the exposed portion of the conductor with respect to the area Sc of the uncovered portion of the terminal member When the ratio of Sd is an area ratio (%) :( Sd / Sc) × 100, the area ratio is 4% or more.

  The electric wire with terminal of the present invention is provided with an insulating coating in a specific range on the surface of the terminal member even if a part of the conductor made of aluminum alloy is exposed without being covered with the insulating layer or the terminal member made of copper or copper alloy. Therefore, it is difficult to form a battery between a conductor made of a different metal and the terminal member, and the corrosion resistance is excellent. Therefore, the electric wire with terminal of the present invention can be suitably used for automobile parts that are desired to be lightweight and excellent in corrosion resistance. Hereinafter, the present invention will be described in more detail.

[Electrical wire]
<Conductor>
"composition"
As the aluminum (Al) alloy constituting the conductor of the electric wire, various compositions having an additive element and the balance of Al and inevitable impurities can be used. Examples of the additive element include one or more selected from Fe, Mg, Si, Cu, Zn, Ni, Mn, Ag, Cr, and Zr. A preferable total content of additive elements is 0.005% by mass or more and 5.0% by mass or less, and more preferably 0.1% by mass or more and 2.0% by mass or less. The preferred content of each element is mass%, Fe: 0.005% to 2.2%, Mg: 0.05% to 1.0%, Mn, Ni, Zr, Zn, Cr, and Ag: 0.005% to 0.2% in total Cu: 0.05% to 0.5%, Si: 0.04% to 1.0%. These additive elements may be contained alone or in combination of two or more. Examples of such alloys include Al-Fe alloys, Al-Fe-Mg alloys, Al-Fe-Si alloys, Al-Fe-Mg- (Mn, Ni, Zr, Ag) alloys, and Al-Fe-Cu alloys. Al-Fe-Cu- (Mg, Si) alloy, Al-Mg-Si-Cu alloy, and the like.

Specific examples of the Al alloy include the following (1) to (6).
(1) By mass%, Fe is 0.90% or more and 1.20% or less, Mg is 0.10% or more and 0.25% or less, and the balance is Al and inevitable impurities.
(2) By mass%, Fe is 1.01% or more and 2.2% or less, Mg is 0.05% or more and 0.5% or less, and one or more elements selected from Mn, Ni, Zr, and Ag are combined in a total of 0.005% or more and 0.2%. Contains below, the balance being Al and inevitable impurities.
(3) By mass%, Fe contains 1.01% or more and 2.2% or less, Cu contains 0.05% or more and 0.5% or less, and the balance is Al and inevitable impurities.
(4) Containing at least one of Fe by 1.0% to 2.2%, Cu by 0.05% to 0.5%, Mg by 0.1% to 0.5%, and Si by 0.04% to 0.3% by mass. Contains, the balance being Al and inevitable impurities.
(5) By mass%, Mg is 0.2% to 1.0%, Si is 0.1% to 1.0%, Cu is 0.1% to 0.5%, the balance being Al and inevitable impurities.
(6) By mass%, Mg is 0.2% to 1.0%, Si is 0.1% to 1.0%, Cu is 0.1% to 0.5%, the balance being Al and inevitable impurities. However, the mass ratio Mg / Si of Mg and Si satisfies 0.8 ≦ Mg / Si ≦ 2.7.

  Fe increases the strength of the Al alloy, and the higher the content, the higher the strength of the Al alloy, but the electrical conductivity and toughness tend to decrease, and wire breakage is likely to occur during wire drawing, so Fe: 2.2 mass % Or less is preferable. Mn, Ni, Zr, and Cr are elements that have a high strength improvement effect, although the electrical conductivity of the Al alloy is greatly reduced. Ag and Zn are less likely to reduce the electrical conductivity of the Al alloy and have a strength improvement effect. Have some. Cu has little decrease in the electrical conductivity of the Al alloy and can improve the strength. Although Mg has a large decrease in electrical conductivity of the Al alloy, the effect of improving the strength is high, and the strength can be further improved by containing it together with Si. In addition, when aging is performed when Mg and Si are contained, an improvement in strength due to age hardening can be expected.

  Furthermore, when the Al alloy contains at least one of Ti and B, there is an effect of making the crystal structure of the Al alloy at the time of casting fine, and an improvement in strength due to the fine crystal structure can be expected. In order to sufficiently obtain this fine effect, it is preferable that Ti is contained in a mass ratio of 100 ppm to 500 ppm and B is contained in an amount of 10 ppm to 50 ppm.

《Conductor shape》
As for the said conductor, the single wire which consists of Al alloy which consists of the said composition is mentioned, for example. Various shapes can be cited for the cross-sectional shape of the single wire. A cross-sectional circular shape is typical, and other cross-sectional shapes such as an elliptical shape, a polygonal shape such as a rectangle or a hexagon are listed. Examples of other conductor forms include a stranded wire obtained by twisting a plurality of the above-mentioned single wires, a compressed wire material obtained by compression-molding a stranded wire, and the like. For example, a high-strength conductor can be obtained by twisting a plurality of single wires such as 7, 11, 19, and 37 wires. Moreover, if it is a compression wire, it can be set as the conductor whose wire diameter is smaller than the state twisted together.

"Characteristic"
The conductor preferably has electrical conductivity: 58% IACS or more and elongation: 10% or more, more preferably conductivity: 59% IACS or more, and elongation: 25% or more. By being excellent in toughness, the conductor hardly breaks in the vicinity of the boundary between the conductor and the terminal member. The conductor preferably has a tensile strength of 110 MPa or more and 200 MPa or less because both high toughness and high strength can be achieved. By appropriately adjusting additive elements (type and content), manufacturing conditions (working degree during wire drawing (cross-sectional reduction rate), softening conditions, etc.), conductivity, elongation, and tensile strength are within the above specified ranges. A satisfying conductor is obtained.

<Cross-sectional area>
When the cross-sectional area of the conductor is large, the completely exposed portion of the conductor tends to be large, and therefore the conductor tends to hardly corrode even if the terminal member does not have an insulating coating. For example, in the case of conductors for electric wires for automobiles, the conductor for power cables has the largest cross-sectional area, which is about 100 mm ² (100 sq). On the other hand, among the electric wires for automobiles, many of the conductors for signal wires have a cross-sectional area of 50 mm ² or less. If the cross-sectional area of the conductor is 8 mm ² (8 sq) or less, especially 3 mm ² (3 sq) or less, and the cross-sectional area is 1 mm ² (1 sq) or less, and the terminal member has an insulation coating, the corrosion resistance will be reduced. The improvement effect tends to be large.

"Production method"
The Al alloy wire constituting the conductor can be formed by, for example, a process of casting → hot rolling → (in the case of billet cast material: homogenization treatment) → cold drawing (→ softening treatment as appropriate). .

  The casting may be billet casting, but continuous casting is preferred in which a cast material having a microstructure is obtained by refining crystal grains and crystal precipitates by rapid solidification. By continuous casting, it is possible to improve strength by refining crystals and toughness by dispersing fine crystal precipitates. For rapid cooling, a water-cooled copper mold or a forced water cooling mechanism may be used. The cooling rate is preferably 20 ° C./sec or more at 600 to 700 ° C.

  When adding Ti or B, adding just before pouring the molten metal into the mold is preferable because it suppresses local sedimentation of Ti and the like and can produce a cast material in which Ti and the like are evenly mixed. .

  When the above casting process and rolling process are carried out continuously, it is possible to easily perform hot rolling using the heat accumulated in the cast material, and it is energy efficient and compared with a batch casting method. In addition, it is excellent in productivity of cast rolled material.

  In the wire drawing step, the degree of processing can be appropriately selected according to the desired wire diameter. As for the obtained wire drawing material, a desired number can be prepared and twisted together to make a stranded wire or a compression wire.

  The softening treatment is performed in order to increase the toughness of the wire by softening without extremely reducing the strength of the wire that has been increased by refinement of the crystal structure and work hardening. The conditions for the softening treatment may be appropriately selected. For example, the softening treatment is performed under such conditions that the elongation of the wire material (single wire, stranded wire, etc.) after the treatment is 10% or more. For the softening treatment, either continuous treatment or batch treatment can be used. In the case of a stranded wire or a compressed wire, the softening treatment may be performed only on the wire before twisting, may be performed both before and after the twisting, or not on the wire drawing material before the twisting. Or may be applied only to the compressed wire.

[Coating layer]
Corrosion resistance can be further improved by providing a metal coating layer so as to cover at least the outer periphery of the exposed portion of the conductor. It is preferable that at least the outermost layer of the metal coating layer is made of one selected from tin (Sn), tin alloy, nickel (Ni), nickel alloy, zinc (Zn), and zinc alloy.

  Sn is a noble metal than Al. When Sn is present between Al alloy and copper or copper alloy, the corrosion current of Al is reduced, and the electric current between Al alloy and copper or copper alloy is reduced. Eating can be reduced. Examples of the tin alloy include a Cu—Sn alloy, and the corrosion current tends to be reduced more easily than Sn. Ni has a small potential difference from copper or copper alloy, and it is difficult to make a battery with copper or copper alloy, so that electrolytic corrosion between Al alloy and copper or copper alloy can be reduced. Examples of the nickel alloy include Ni-P alloy, Ni-B alloy, Ni-Zn alloy and the like. Zn is more easily corroded than Al and Cu. When Zn is present on the surface of the Al alloy, the corrosion of the inner Al alloy can be delayed by causing Zn to corrode at the sacrifice. Examples of the zinc alloy include a Zn—Al alloy, which tends to delay the corrosion of the Al alloy more than Zn.

  The metal coating layer may be a single layer made of only Sn or the like, or a multilayer having an intermediate layer made of a material different from the outermost layer between the outermost layer made of Sn and the surface of the conductor. Good. Examples of the constituent material of the intermediate layer include at least one metal selected from Sn, Sn alloy, Ni, Ni alloy, copper (Cu), copper alloy, Zn, and Zn alloy. The intermediate layer may be one layer or two or more layers. Examples of the copper alloy include a Cu—Sn alloy and a Cu—Zn alloy. By providing the intermediate layer, the adhesion between the conductor and the outermost layer can be enhanced, and the corrosion resistance can be enhanced.

  The metal coating layer may be provided not only on the completely exposed portion of the conductor but also on the entire exposed portion of the conductor, and further on the entire conductor. Moreover, when a conductor is a strand wire or a compression wire, the metal coating layer may be provided in the outer periphery of each strand which comprises a conductor, and may be provided in the outer periphery of a strand wire or a compression wire. In particular, when the metal coating layer is provided not only on the peripheral surface of the conductor but also on the end surface, the corrosion resistance can be further improved.

  Even if the total thickness of the metal coating layer is very thin, such as 15 μm or less, it is sufficiently effective for improving the corrosion resistance. When it is thicker than 15 μm, the metal coating layer is easily peeled off when the terminal member is attached. The total thickness of the metal coating layer is more preferably 10 μm or less.

  The metal coating layer can be formed by various methods such as a plating method, a vapor deposition method such as a CVD method and a PVD method. Plating methods such as electroplating, electroless plating, and hot dipping can easily form a metal coating layer. Moreover, when forming an intermediate | middle layer with Zn, a zincate process, a double zincate process, etc. can be utilized suitably. A forming method may be appropriately selected according to the constituent material of the metal coating layer. When the softening treatment is performed and the constituent material of the metal coating layer has a melting point lower than the heating temperature during the softening treatment, the metal coating layer is formed after the softening treatment. When the constituent material of the metal coating layer has a melting point higher than the heating temperature during the softening treatment, the metal coating layer can be formed either before or after the softening treatment.

<Insulating layer>
Examples of the constituent material of the insulating layer provided on the outer periphery of the conductor include polyvinyl chloride (PVC), a non-halogen resin, and an insulating material having excellent flame retardancy. The material and thickness of the insulating layer can be appropriately selected in consideration of desired insulating strength, and are not particularly limited.

[Terminal materials]
A terminal member made of copper or a copper alloy is attached to the conductor at the end of the electric wire. This terminal member is a member interposed in order to electrically connect the electric wire to an external terminal connected to an external device or the like, and is typically a contact portion with an exposed portion of the conductor of the electric wire on one end side. A male terminal or a female terminal having a contact portion with the external terminal on the other end side. The terminal member may be attached to only one electric wire or may be attached to a plurality of electric wires. Such a terminal member is preferably a crimp terminal that can be attached by crimping (crimping) to the end of the electric wire. In the case of copper, the conductivity is high, and in the case of copper alloy, the mechanical properties such as strength are excellent. Examples of the copper alloy include brass (Cu—Zn alloy), Cu—Sn alloy, Cu—Fe alloy, Cu—Ni—Sn alloy, Cu—Fe—P alloy, and the like. As the basic structure of the terminal member, a known one can be used. And in the electric wire with a terminal of the present invention, at least a part of the terminal member, specifically, a contact part with the exposed part of the conductor and a contact part with the external terminal, at least part of the non-contact area is as follows. Insulating insulation.

[Insulation coating]
<Material>
Insulating coatings are composed of insulating synthetic resins such as acrylic resin, acrylonitrile-styrene (AS) resin, acrylonitrile-butadiene-styrene (ABS) resin, polyurethane resin, melamine resin, epoxy resin, phenol resin, polyethylene resin. Polypropylene resin, vinyl chloride resin, polystyrene resin, polyethylene terephthalate (PET) resin, vinylidene chloride resin, fluorine resin, and the like.

<Characteristic>
The insulating coating preferably has excellent insulating properties so as to reduce battery formation, and satisfies at least one of a volume resistivity of 10 ⁸ Ω · cm or more and a dielectric breakdown strength of 200 V / mm or more. preferable. The insulating coating preferably has a breakdown voltage value of 10 V or more. It is advisable to select the material and thickness of the insulation coating so as to achieve the desired insulation characteristics.

<Method for forming insulating coating>
The insulation coating can be applied by using various coating methods such as electrodeposition coating, powder coating, electrostatic coating, and baking coating, or by applying a liquid material such as paint, or tape. It can be formed by pasting (masking) a band-like body on the surface. The insulation coating may be formed either before or after the terminal member is attached to the electric wire. That is, the terminal member of the present invention (described later) in which an insulating coating is previously formed on the terminal member may be used. The formation method of the insulating coating may be appropriately selected depending on the type of material, the formation time, and the like.

<Coating area>
The insulating coating is such that the area ratio (Sd / Sc) × 100 of the area Sd of the exposed portion exposed from the insulating layer in the conductor and the area Sc of the non- coated portion of the terminal member is 4% or more. By comprising, the electric corrosion between the conductor and terminal member which consist of a dissimilar metal can be reduced. The area ratio is preferably as high as possible, 9% or more, and more preferably 14% or more. More preferably, an insulating coating is provided over the entire non-contact area. Predetermined insulation characteristics (e.g., insulating fracture 壊強 Saga 200V / mm or more) and an insulating coating having a and the covering region is increased to be to increase the area ratio, it is possible to improve the corrosion resistance.

[Terminal member with insulation coating]
The terminal member of the present invention having an insulating coating can be used as the terminal member. The terminal member of the present invention is a member that is attached to an exposed portion of a conductor exposed by removing an insulating layer at an end portion of an electric wire whose conductor is made of an aluminum alloy, and is made of copper or a copper alloy. In this terminal member, at least a part of the non-contact area except for the contact portion with the exposed portion of the conductor and the contact portion with the external terminal is covered with an insulating coating. This insulating coating is Sd as the area of the exposed portion of the conductor to which the terminal member is attached, Sc as the area of the uncovered portion that is not covered by the insulating coating on the terminal member, and the area Sc of the uncovered portion as described above. When the ratio of the area Sd of the exposed portion of the conductor is an area ratio (%) :( Sd / Sc) × 100, the area ratio is provided so as to satisfy 4% or more.

[Method of manufacturing electric wire with terminal]
By stripping the insulating layer at the end of the electric wire described above to expose a part of the conductor, and attaching the terminal member to this exposed location, forming an insulating coating, or attaching the above-described terminal member of the present invention, The electric wire with a terminal of the present invention is obtained. When forming the insulation coating after attaching the terminal member to the electric wire, a commercially available product can be used as it is as the terminal member. When the terminal member of the present invention is used, the electric wire with terminal of the present invention can be easily obtained and an insulating coating can be easily formed. In addition, the resin coating has good elongation compared to metal plating and the like, and it is difficult to peel off when attaching the terminal member of the present invention to the end of the wire. Corrosion of the conductor can be reduced. When it is a form including the electric wire group which shares one terminal member with respect to a some electric wire, it will be excellent in handling property, if a several insulated electric wire is bundled together with a binding tool.

[Usage]
The electric wire with terminal of the present invention can be suitably used in various fields where weight reduction is desired, particularly in automobiles where further weight reduction is desired in order to improve fuel consumption.

  The electric wire with terminal of the present invention is excellent in corrosion resistance. By using the terminal member of the present invention, a terminal-attached electric wire having excellent corrosion resistance can be obtained.

FIG. 1 is a partial configuration diagram showing an outline of a terminal-attached electric wire.

  A terminal-attached electric wire with a crimp terminal (terminal member) attached to the end portion of the electric wire using an Al alloy wire as a conductor was prepared, and a corrosion test was performed to evaluate the corrosion resistance.

  Among the samples, the electric wire was produced by the procedure of casting → rolling → drawing → twisting wire → softening → insulating layer formation. Specifically, pure aluminum (99.7% by mass or more Al) is prepared and melted as a base, and additive elements (here, Fe, Mg) are added to the obtained molten metal (molten aluminum) to obtain molten Al alloy. Make it. It is desirable that the Al alloy molten metal whose components have been adjusted is appropriately subjected to a hydrogen gas removal treatment or a foreign matter removal treatment.

  Using a belt-wheel type continuous casting and rolling machine, the prepared molten Al alloy is continuously cast and hot-rolled to produce a φ9.5 mm wire rod (continuously cast rolled material).

The wire rod is subjected to cold wire drawing to produce wire drawing materials having various wire diameters. A plurality of the obtained wire drawing materials are prepared, and an appropriate number is twisted to produce a stranded wire. For example, for a sample with a wire size of 0.75 mm ² , 11 wire drawing materials having a wire diameter of φ0.3 mm are prepared and twisted so that 3 wire wires are arranged inside and 8 wire wires are arranged outside.

  The obtained stranded wire is subjected to softening treatment (batch treatment, reducing gas atmosphere) at 350 ° C. for 3 hours to obtain a soft material. The obtained soft material is a conductor (1.05% Fe-0.15% Mg-Al, the unit is mass%). When the electrical conductivity, elongation, and tensile strength of each wire constituting the obtained soft material were examined, the electrical conductivity: 58% IACS or more, elongation: 10% or more, and tensile strength: 110 It was ~ 200MPa. An insulating layer (thickness 0.2 mm) is formed on the outer periphery of the obtained conductor with an insulating material (here, a halogen-free insulating material) to produce an electric wire. The insulating layer is removed at the end of the insulated wire to expose the conductor, and a crimp terminal is attached to the exposed portion of the conductor to produce the terminal-attached wire shown in FIG.

  The electric wire with terminal 1 includes an electric wire 10 including a conductor 11 formed by twisting a plurality of Al alloy wires, and an insulating layer 12 covering the outer periphery of the conductor 11, and an insulating layer 12 on one end side of the conductor 11 is peeled off. And a terminal member (crimp terminal) 20 attached to the exposed portion exposed. The terminal member 20 is a general female terminal formed by bending a piece formed by appropriately making cuts on both edge sides of the copper alloy plate, and is suitably bent so that the edges of both the pieces 22a and 22b on one end side are in contact with each other. A rectangular cylindrical female terminal portion 22 is formed. Further, both the segments 21a and 21b on the other end side of the terminal member 20 are bent so as to sandwich the insulating layer 12 near the exposed portion of the conductor 11 in the electric wire 10. In the terminal member 20, the exposed portion of the conductor 11 is vertically attached to the intermediate portion between the sandwiched portion of the insulating layer portion and the female terminal portion 22, and both pieces 23a, so as to sandwich the exposed portion of the conductor 11. 23b is bent. Most of the exposed portions of the conductor 11 are covered with the pieces 23a and 23b, and the end face and the vicinity thereof and the vicinity of the insulating layer 12 are exposed from the pieces 23a and 23b.

  In this test, sample Nos. 1 to 10 having an insulating coating on a part of the surface of the terminal member and sample Nos. 101 and 102 having no insulating coating were prepared. Table 1 shows the material and method of forming the insulation coating. A known method was used for coating and electrodeposition. For masking, an insulating coating was formed by attaching a commercially available tape having an adhesive layer to a predetermined location. Sample Nos. 1 to 10 are the above-mentioned terminal member 20 in contact with the exposed portion of the conductor 11, and in the female terminal portion 22 in contact with an external terminal (here, a male terminal (not shown)) (here. Table 1 shows the substantially whole area of the non-contact area (except the inner peripheral surface of the rectangular cylindrical female terminal portion 22), mainly the outer peripheral surface of the female terminal portion 22, and the outer peripheral surfaces of the sections 21a, 21b, 23a, 23b. A sample having an insulating coating in the range shown in Table 1. In particular, Samples Nos. 1 to 4 and 7 to 9 are samples using a terminal member in which an insulation coating has been formed in advance. This is a sample.

Further, in Table 1, the area Sd (mm ² ) of the exposed portion exposed by peeling off the insulating layer in the conductor, the area Sc (mm ² ) of the non-coated portion where the insulating coating is not applied to the terminal member, and the area Ratio (%): (Sd / Sc) × 100. Here, the area Sd of the exposed portion of the conductor is the total area of the outer peripheral surface of each strand constituting the conductor. In addition, the thickness (μm) of the insulation coating and the breakdown voltage (V) were measured. The results are also shown in Table 1. The thickness of the insulation coating is measured by observing a cross section of the sample with a microscope and using this observation image, and the breakdown voltage is measured by bringing a gold wire probe into contact with the insulation coating of each sample with zero load. The voltage at the start of energization due to the voltage rise was measured.

  The corrosion resistance of the prepared electric wires with terminals was evaluated as follows. The salt spray test is known as a corrosion resistance test. However, if the salt spray test is applied to a sample that is composed of dissimilar metals and can undergo electrolytic corrosion, such as the sample in this test, the sample may be damaged by electrolytic corrosion. It is too large to evaluate the corrosion resistance substantially. Therefore, in order to appropriately evaluate the corrosion resistance of a sample in which such electrolytic corrosion can occur, the following test method simulating an environment where the progress of corrosion is performed relatively slowly was adopted.

First, NaCl (electrolyte) is dissolved in ultrapure water (solvent) to prepare a neutral aqueous solution (200 g) having a concentration of 26% by mass. Further, 100 g of silica (SiO ₂ ) powder having an average particle diameter of about 100 μm is prepared. The electrolyte, solvent, and silica powder used are all commercially available products.

The prepared silica powder is placed on a filter paper, and the prepared aqueous solution (26% NaCl) is dropped from above the silica powder, then placed in a thermostatic chamber heated to 150 ° C., dried, and the NaCl adheres. the obtained (Cl ^- deposition amount: 35,000 ppm). Sprinkle the obtained powder evenly on the sample (especially the joint between the conductor and the terminal member) so that a part of the sample can be visually confirmed (thickness of 1 mm or less), and set to 60 ° C and 95% RH. Put in a thermo-hygrostat and hold for 6 days (144 hours). Six days later, the sample was taken out from the thermo-hygrostat and the corrosion state was examined. Specifically, in FIG. 1, the exposed portion of the conductor 11 and the vicinity of the portion sandwiched between the sections 23a and 23b are cut (BB cut), and this cross section is observed, and the residual rate (%) = {(Area of remaining Al alloy wire) / (Area of fabricated Al alloy wire)} × 100 is determined, and corrosion resistance is evaluated based on the residual rate. The area can be easily obtained by performing image processing or the like on the cross-sectional photograph. It can be said that the higher the residual ratio, the higher the corrosion resistance. The results are shown in Table 1. In addition, when the salt spray test was performed, the samples No. 101 and 102 were so damaged that the measurement of the area of the remaining Al alloy wire was difficult, but the samples No. 1 to 10 were the remaining Al alloy wires. Was slightly confirmed.

  As shown in Table 1, it can be seen that if the wire size is large to some extent, the area ratio is large even if the terminal member does not have an insulating coating, and a conductor made of an Al alloy remains to some extent. However, in particular, when the wire size is small, it can be seen that the corrosion resistance can be effectively enhanced by having the terminal member with the insulating coating in a specific range. More specifically, a sample in which the non-contact region of the terminal member is provided with an insulating coating and the area ratio is 4% or more has a high residual ratio of the aluminum alloy constituting the conductor, and the conductor (Al alloy) and the terminal member It can be seen that even when (copper) is made of a different metal, the corrosion resistance is excellent. It turns out that it is further excellent in corrosion resistance as the said area ratio is 9% or more. In addition, the sample using a terminal member having an insulating coating does not peel off when the terminal member is attached to the electric wire, and is approximately the same as the sample in which the insulating coating is formed after the terminal member is attached to the electric wire. It turns out that it has corrosion resistance of.

  The above-described embodiment can be appropriately changed without departing from the gist of the present invention, and is not limited to the above-described configuration. For example, the composition of the conductor, the cross-sectional area of the conductor, and the composition of the terminal member may be changed as appropriate. Moreover, when making a conductor into a strand wire, you may change the magnitude | size and shape of a wire to twist together, and the number of twists. Furthermore, it is good also as a form which provided the metal coating layer which consists of Sn, Ni, Zn, and its alloy in the outer periphery of a conductor.

  The electric wire with terminal of the present invention is excellent in corrosion resistance and lightweight, and therefore can be suitably used for wiring of automobiles, other transportation equipment such as aircraft, and wiring of industrial equipment such as robots. This invention terminal member can be suitably utilized for the component of the said electric wire with a terminal of this invention.

1 Wire with terminal 10 Wire 11 Conductor 12 Insulation layer 20 Terminal material
21a, 21b, 22a, 22b, 23a, 23b Section 22 Female terminal

Claims (5)

An electric wire with a terminal comprising: an electric wire having an outer periphery of a conductor made of an aluminum alloy covered with an insulating layer; and a terminal member attached to an exposed portion of the conductor exposed by removing the insulating layer at an end of the electric wire Because
The terminal member is
Consists of copper or copper alloy,
In the terminal member, at least a part of the non-contact region excluding the contact point with the exposed portion of the conductor and the contact point with the external terminal is covered with an insulating coating ,
The wire is
The exposed portion of the conductor is not covered with the insulating coating,
The area of the exposed portion of the conductor is Sd, the area of the non-covered portion of the terminal member that is not covered with the insulating coating is Sc, and the area of the exposed portion of the conductor is Sd relative to the area Sc of the non-covered portion of the terminal member. when the ratio of the area ratio (%) and :( Sd / Sc) × 100, Ru der the area ratio of 4% or more ends of the terminal with the wire. An electric wire with terminal according to Der Ru請 Motomeko 1 wherein the area ratio of 9% or more. The wire with terminals is an electric wire with terminal according to 請 Motomeko 1 or claim 2 that is used in an automobile. A terminal member attached to the exposed portion of the conductor exposed by removing the insulating layer at the end of the electric wire made of an aluminum alloy conductor,
Consists of copper or copper alloy,
In the terminal member , at least a part of a non-contact region except for a contact portion with the exposed portion of the conductor and a contact portion with an external terminal is covered with an insulating coating, and the exposed portion of the conductor in the electric wire is covered with the insulation. Not covered by a coating,
The insulation coating has an area Sd of the exposed portion of the conductor to which the terminal member is attached, Sc an uncovered area of the terminal member that is not covered by the insulation coating, and the area Sc of the non-covered portion. A terminal member provided so that the area ratio satisfies 4% or more when the ratio of the area Sd of the exposed portion of the conductor is an area ratio (%) :( Sd / Sc) × 100 . 2. The insulating coating is formed by one method selected from electrodeposition coating, powder coating, electrostatic coating, baking coating, liquid coating, and application of a strip-shaped body such as a tape. The electric wire with a terminal according to any one of claims 3 to 4.

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