Metallic material for foil thread, foil thread, and twisted yarn and fabric formed using foil thread

Abstract

To provide a metal material for a foil yarn and a foil yarn as well as a twist yarn and clothing formed with the foil yarn, capable of preventing or suppressing a flexure crack when winding to a core material, in particular a core material having a relatively small outer diameter (for example 1.0 mm or less).SOLUTION: A metal material 1 has a ribbon shape constituting a foil yarn 3 wound in spiral on a foil-shaped core material 2, the metal material 1 being made of aluminum or aluminum alloy, where a width direction cross-section of the metal material 1 roughly forms a rectangular shape, and in view of the width direction cross-section of the metal material 1, a thickness t1 of a width direction central portion 4 is 1.05 time or more and 1.20 time or less relative to a thickness t2 of a width direction end portion 5, and tensile strength is 270 MPa or more and 750 MPa or less.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a metal material for foil threads, and more particularly to a ribbon-shaped metal material for foil threads made of high-strength aluminum or an aluminum alloy, foil threads, and twisted yarns and fabrics formed using the foil threads. [Background technology]

[0002] The foil thread has a ribbon-shaped metal foil and a core material, and is constructed by spirally winding the ribbon-shaped metal foil around the core material. Therefore, compared to metal wire rods of the same outer diameter, the foil thread has advantages such as a longer fatigue life and a reduction in weight due to a reduction in the amount of metal used.

[0003] Because foil yarn has the advantages described above, for example, Patent Document 1 describes the use of foil yarn made by wrapping copper foil around a core material as lead wire (tinsel wire) for acoustic speakers. Furthermore, foil yarn is lighter than metal wire of the same outer diameter and has a superior flex fatigue life, so its use in applications where repeated bending is possible has been proposed. For example, Patent Document 2 describes the use of foil yarn made by wrapping copper alloy foil tape around a high-tensile fiber yarn for applications such as robot cables and sensor cables that require flex resistance.

[0004] Patent Document 3 describes a conductive thread that is constructed by spirally winding multiple conductive fibers around a core material, and also describes the use of conductive metal fibers such as copper, copper alloy, silver, iron, and stainless steel as the conductive fibers. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Unexamined Patent Publication No. 53-99479 [Patent Document 2] Japanese Utility Model Application Publication No. 5-53045 [Patent Document 3] Patent No. 5352795 [Patent Document 4] Patent No. 6430080 Summary of the Invention [Problem to be solved by the invention]

[0006] In recent years, the use of foil yarns in so-called wearable devices such as clothing heaters and cameras attached to clothing or hats has been considered. However, for such wearable devices that may come into contact with the skin, the use of the above-mentioned copper-based materials and iron-based materials as materials for constituting the foil yarns is undesirable in terms of the risk of metal allergies, discoloration of the foil yarn due to reaction with sweat, weight reduction, material costs, etc.

[0007] Therefore, if foil yarns could be made of aluminum or aluminum alloys instead of the above-mentioned copper-based or iron-based materials, it would be possible to solve the above-mentioned problems of the risk of metal allergies, discoloration, weight reduction, material costs, etc. However, as described in Patent Documents 1 to 3, known foil yarns are made of copper-based or iron-based materials, and currently there are no foil yarns made by spirally winding a metal foil made of aluminum or an aluminum alloy around a core material.

[0008] Furthermore, the present applicant proposed a ribbon-shaped aluminum alloy material with unprecedentedly increased strength by optimizing the composition of the aluminum alloy and setting the Vickers hardness within a predetermined range in Patent Document 4. However, Patent Document 4 does not describe a foil yarn formed by winding a ribbon-shaped aluminum alloy material around a fiber with a small wire diameter, and in particular does not consider bending cracks, wire breakage, etc. that may occur when a ribbon-shaped aluminum alloy material is wound around a core material with a small wire diameter.

[0009] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a metal material for foil thread and foil thread that can prevent or suppress bending cracks when wound around a core material, particularly a core material having a relatively small outer diameter (e.g., 0.1 mm or less), as well as a twisted yarn and cloth formed using the foil thread. [Means for solving the problem]

[0010] The inventors discovered that by constructing the metal material for foil thread from aluminum or an aluminum alloy having a tensile strength equal to or greater than that of copper and copper alloys, and by setting the thickness of the widthwise central part of the metal material for foil thread, when viewed in widthwise cross section, to be within a predetermined range relative to the thickness of the widthwise ends, bending cracks can be effectively suppressed, even when the metal material for foil thread is spirally wound around a core material having a relatively small outer diameter (for example, 0.1 mm or less) to form a foil thread, and thus completed the present invention.

[0011] In order to achieve the above object, the gist of the present invention is as follows. (1) A metal material for foil threads having a ribbon shape that is spirally wound around a thread-like core material to form a foil thread, the metal material being made of aluminum or an aluminum alloy, the widthwise cross section of the metal material being approximately rectangular, and when viewed in the widthwise cross section of the metal material, the thickness of the widthwise central part is 1.05 to 1.20 times the thickness of the widthwise end parts, and the tensile strength is 270 MPa to 750 MPa.

[0012] (2) The aluminum alloy is a metal material for foil thread described in (1) above, having an alloy composition containing 0.10% by mass or more and 1.80% by mass or less of magnesium, 0.20% by mass or more and 2.10% by mass or less of silicon, 0.01% by mass or more and 2.00% by mass or less of iron, with the remainder being aluminum and unavoidable impurities.

[0013] (3) The aluminum alloy is a metal material for foil yarn according to (1) above, having an alloy composition comprising 0.10% by mass or more and 1.80% by mass or less of magnesium, 0.20% by mass or more and 2.10% by mass or less of silicon, 0.01% by mass or more and 2.00% by mass or less of iron, and further comprising 0.02% by mass or more and 2.00% by mass or less of at least one component selected from the group consisting of titanium, boron, copper, silver, zinc, nickel, cobalt, gold, manganese, chromium, vanadium, zirconium and tin, with the remainder being aluminum and unavoidable impurities.

[0014] (4) The metal material has an average thickness of 0.005 mm or more and 0.500 mm or less, an average width of 0.10 mm or more and 2.0 mm or less, and a cross-sectional area measured in the width direction of the metal material is 0.80 mm or less. 2 The metal material for foil thread according to any one of the above (1) to (3) is as follows:

[0015] (5) A foil thread formed by spirally winding the metal material for foil thread according to any one of (1) to (4) above around the core material.

[0016] (6) A metal material for foil thread according to (5) above, wherein the ratio (W / D) of the width (W) of the metal material to the outer diameter (D) of the core material is greater than 0.5 and less than 5.0.

[0017] (7) A twisted yarn formed by twisting together at least two or more foil yarns described in (6) above.

[0018] (8) A fabric formed by combining a plurality of foil yarns described in (6) above. [Effects of the Invention]

[0019] According to the present invention, it is now possible to provide a metal material for foil thread and foil thread that can prevent or suppress bending cracks when wound around a core material, particularly a core material having a relatively small outer diameter (e.g., 0.1 mm or less), as well as a twisted yarn and fabric formed using the foil thread. [Brief explanation of the drawings]

[0020] [Figure 1] 1 is a diagram showing an example of a metal material for foil thread according to an embodiment of the present invention. FIG. [Figure 2] FIG. 2 is a diagram showing an example of a thread-like core material constituting a foil yarn according to an embodiment of the present invention. [Figure 3] FIG. 1 is a diagram showing an example of a foil yarn according to an embodiment of the present invention. [Figure 4] FIG. 2 is an enlarged view showing a widthwise cross section of a metal material for foil thread. DETAILED DESCRIPTION OF THE INVENTION

[0021] Next, the metal material for foil yarn and the foil yarn using the same according to the embodiment of the present invention will be described below.

[0022] FIG. 1 is a diagram showing an example of a metal material for a foil thread according to an embodiment of the present invention, FIG. 2 is a diagram showing an example of a thread-like core material constituting a foil thread according to an embodiment of the present invention, FIG. 3 is a diagram showing an example of a foil thread according to an embodiment of the present invention, and FIG. 4 is a diagram showing an enlarged widthwise cross section of a metal material for a foil thread.

[0023] [Metallic materials for foil thread] The metal material for foil thread (hereinafter simply referred to as "metal material") 1 has a ribbon shape as shown in FIG. 1 and is spirally wound around a thread-like core material 2 as shown in FIG. 2 to form a foil thread 3. Here, "ribbon shape" refers to a flat thread shape, tape shape, band shape, etc. More specifically, the widthwise cross section of the metal material 1 is substantially rectangular as shown in FIG. 4. When viewed in its widthwise cross section, the thickness t1 of the widthwise central portion 4 (hereinafter simply referred to as "center portion") of the metal material 1 is set to be 1.05 to 1.20 times the thickness t2 of the widthwise end portion 5 (hereinafter simply referred to as "end portion") of the metal material 1. The metal material 1 shown in FIG. 4 is formed so that the thickness t gradually decreases from the central portion 4 toward both end portions 5.

[0024] The above-mentioned substantially rectangular shape includes, for example, a rectangular shape in which the four corners are smoothly curved and connected to each other, a flattened elliptical shape, a flattened oval shape, and the like. The metal material 1 of the embodiment shown in Figure 4 shows a case in which the end faces located at both ends in the width direction form convex curved surfaces. Note that the width direction of the metal material 1 refers to the direction in which the long sides of the substantially rectangular metal material 1 extend (the left-right direction in Figure 4), as shown in Figure 4, and the thickness refers to the length in the direction in which the short sides of the substantially rectangular metal material 1 extend (the up-down direction in Figure 4).

[0025] Furthermore, the widthwise central portion 4 of the metal material 1 refers to the portion of the widthwise cross section of the metal material 1 shown in FIG. 4 that is centered on the midpoint of the line segment connecting the vertices of both end faces forming the convex curved surface of the metal material 1, i.e., the width W of the metal material 1. Furthermore, the widthwise end portion 5 of the metal material 1 refers to the portion of the widthwise cross section of the metal material 1 that is centered at a position corresponding to 95% of the length from the widthwise central portion 4 to the vertex, when measured from the widthwise central portion 4 to the vertex. The widthwise end portion 5 of the metal material 1 refers to the outermost portion of the portion of the metal material 1 that contacts the core material 2 when the metal material 1 is spirally wound around the core material 2 to form the foil thread 3, as shown in FIG. 3. The widthwise end portion 5 of the metal material can be determined in advance by experiment or other means.

[0026] In an embodiment of the present invention, the ratio of the thickness t1 of the central portion 4 to the thickness t2 of the end portion 5 (t1 / t2 ratio) is set to be 1.05 or more and 1.20 or less, as described above. If the t1 / t2 ratio is less than 1.05, when the metal material 1 is spirally wound around the core material 2 as shown in FIG. 3, shear bands generated during thin rolling tend to fracture, resulting in linear fracture. If the t1 / t2 ratio exceeds 1.20, the central portion becomes thicker, and the bending conditions become more severe for the same bending diameter. This makes shear bands more likely to form, and bending cracks are more likely to occur from the shear bodies. For this reason, in the present invention, the ratio of the thickness t1 of the central portion 4 to the thickness t2 of the end portion 5 (t1 / t2 ratio) is set to be 1.05 or more and 1.20 or less. Linear fracture refers to fracture of the metal material 1 caused by being stretched beyond its tensile strength. Shear bands are thin, plate-like structures that are tilted at approximately 35 degrees to the longitudinal direction of the foil when localized strain is applied to the metal, such as during bending or rolling. They occur when large shear strain is applied to the localized deformation area due to bending or rolling. If the formation of these shear bands progresses due to fatigue during long-term use, many shear bands will form near the location where the shear bands were formed, leading to bending cracks or fractures at those locations.

[0027] Furthermore, it is preferable to set the width W of the metal material 1 so that the ratio (W / D ratio) of the width W to the outer diameter D of the core material 2 around which the metal material 1 is wound is greater than 0.5 and less than 5.0. That is, if the W / D ratio is 0.5 or less, the width W of the metal material 1 becomes relatively narrow, or the outer diameter D of the core material 2 becomes relatively thick. Therefore, the winding amount or twist ratio of the metal material 1 wound per unit length of the core material 2 increases, which can lead to concerns about increased resistance when electricity is applied, an increase in the weight of the foil thread 3 per unit length, and breakage of the metal material 1 due to unwinding of the metal material 1 due to bending or twisting. In the worst case scenario, a short circuit may occur during electrical current application. Furthermore, material costs may increase.

[0028] On the other hand, if the W / D ratio is 5.0 or more, the width W of the metal material 1 becomes relatively wide, or the outer diameter of the core material 2 becomes relatively narrow. As a result, the bending diameter when the metal material 1 is wound around the core material 2 becomes small, which may cause bending cracks during processing into the foil thread 3 or during manufacturing. Furthermore, if the bending diameter when the foil thread 3 is bent is small, not only the part of the core material 2 exposed from the gaps 6 in the metal material but also the part of the metal material 1 wound around the core material 2 may be bent together, which may cause bending cracks or breakage in the metal material 1. Therefore, it is preferable to set the W / D ratio to be greater than 0.5 and less than 5.0.

[0029] The metal material 1 can be made of, for example, (pure) aluminum or an aluminum alloy, and its tensile strength must be 270 MPa or more and 750 MPa or less. That is, when the metal material 1 is wound onto, for example, a bobbin or roll (not shown), a predetermined tension is applied to the metal material 1 to prevent it from unwinding. Therefore, to prevent the metal material 1 from breaking during winding, the tensile strength must be 270 MPa or more. Furthermore, if the tensile strength exceeds 750 MPa, the metal material 1 will unwind when wound onto a bobbin or roll, making it difficult to wind.

[0030] An example of pure aluminum is 1000-series aluminum containing 99% or more by mass of aluminum. Furthermore, in order to perform wire drawing or rolling to a desired small diameter without causing processing defects such as wire breakage or cracking, the parent phase and aluminum alloy must have a structure that can withstand deformation during these processes. Based on this, in an embodiment of the present invention, the aluminum alloy is preferably a 6000-series aluminum alloy or an 8000-series aluminum alloy, and of these aluminum alloys, 6000-series aluminum is more preferred in terms of strength and processability.

[0031] [Aluminum alloy composition] To specifically explain the composition of the aluminum alloy that constitutes the metal material 1, the ratio of the added elements needs to be adjusted based on the compositions of clusters, intermetallic compounds, and precipitates. Based on this, the aluminum alloy material that constitutes the metal material 1 preferably has an alloy composition that contains 0.10% by mass to 1.80% by mass of magnesium, 0.20% by mass to 2.10% by mass of silicon, and 0.01% by mass to 2.00% by mass of iron, with the balance being aluminum and unavoidable impurities. In the following description, each of the above-mentioned elements will be represented by its element symbol.

[0032] <Magnesium: 0.10% by mass or more and 1.80% by mass or less> Magnesium (Mg) dissolves in the aluminum matrix to strengthen it, and also improves tensile strength through a synergistic effect with Si. However, if the Mg content is less than 0.10% by mass, the above effects are insufficient. If the Mg content exceeds 1.80% by mass, crystallized deposits are formed, reducing workability (wiredrawability, bending workability, etc.). Therefore, the Mg content is set to 0.10 to 1.80% by mass, and preferably 0.40 to 1.40% by mass.

[0033] <Silicon: 0.20% by mass or more and 2.10% by mass or less> Silicon (Si) dissolves in the aluminum matrix to strengthen it, and also improves tensile strength and flexural fatigue resistance through a synergistic effect with magnesium. However, if the Si content is less than 0.20% by mass, the above effects are insufficient. If the Si content exceeds 2.10% by mass, crystallized deposits are formed, reducing workability. Therefore, the Si content is set to 0.20 to 2.10% by mass, and preferably 0.40 to 1.40% by mass.

[0034] <Iron: 0.01% by mass or more and 2.00% by mass or less> Iron (Fe) is an element that contributes to grain refinement and improves tensile strength by forming intermetallic compounds, primarily Al-Fe. Here, intermetallic compounds refer to compounds composed of two or more metals. Fe can only dissolve in Al at 655°C (0.05% by mass), and even less at room temperature. Therefore, the remaining Fe that cannot dissolve in Al crystallizes or precipitates as intermetallic compounds, such as Al-Fe, Al-Fe-Si, and Al-Fe-Si-Mg. These intermetallic compounds primarily composed of Fe and Al are referred to as Fe-based compounds in this specification. These intermetallic compounds contribute to grain refinement and improve tensile strength. Fe content less than 0.01% by mass results in insufficient effects. Fe content greater than 2.00% by mass results in increased crystallization and reduced workability. Here, crystallization refers to intermetallic compounds that form during the casting and solidification of the alloy. Therefore, the Fe content is set to 0.01 to 2.00 mass%, preferably 0.05 to 0.28 mass%, and more preferably 0.05 to 0.23 mass%. If the cooling rate during casting is slow, the dispersion of Fe-based compounds becomes sparse, increasing the degree of adverse effects.

[0035] Furthermore, it is preferable that the aluminum alloy material constituting the metal material 1 has an alloy composition that contains 0.10% by mass or more and 1.80% by mass or less of magnesium, 0.20% by mass or more and 2.10% by mass or less of silicon, and 0.01% by mass or more and 2.00% by mass or less of iron, and further contains a total of 0.02% by mass or more and 2.00% by mass or less of at least one component selected from the group consisting of titanium, boron, copper, silver, zinc, nickel, cobalt, gold, manganese, chromium, vanadium, zirconium, and tin, with the remainder being aluminum and unavoidable impurities.

[0036] <At least one component selected from the group consisting of rare earth elements, titanium, boron, copper, silver, zinc, nickel, cobalt, gold, manganese, chromium, vanadium, zirconium, and tin: 0.02% by mass or more and 2.00% by mass or less in total> Rare earth elements (RE), Cu (copper), Ag (silver), Zn (zinc), Ni (nickel), Co (cobalt), Au (gold), Mn (manganese), Cr (chromium), V (vanadium), Zr (zirconium), Sn (tin), Ti (titanium), and B (boron) are all elements that refine the grain size during casting, reduce the number of specific voids, and improve strength and heat resistance. These optional elements can be added as needed. The mechanisms by which these elements improve heat resistance include reducing the energy of grain boundaries due to the large difference between the atomic radii of these elements and aluminum, reducing grain boundary mobility when they penetrate into grain boundaries due to their large diffusion coefficients, and slowing the diffusion phenomenon by trapping vacancies due to their strong interaction with vacancies. These mechanisms are thought to work synergistically. RE stands for rare earth elements, and includes 17 elements such as lanthanum, cerium, and yttrium. These 17 elements have similar effects, and since it is difficult to extract each element chemically, they are defined as the total amount in this invention.

[0037] RE, B, Cu, Ag, Zn, Ni, Ti, Co, Au, Mn, Cr, V, Zr, and Sn are all elements that particularly improve heat resistance. To fully exert these effects, it is preferable that the total content of these optional additive components be 0.02% by mass or more. However, if the total content of these components exceeds 2.00% by mass, workability may be reduced. Therefore, when one or more elements selected from the group consisting of RE, Cu, Ag, Zn, Ni, Co, Au, Mn, Cr, V, Zr, Sn, Ti, and B are contained, the total content thereof is 2.00% by mass or less, preferably 0.06 to 2.00% by mass, and more preferably 0.30 to 1.20% by mass. These elements may be contained alone or in combination of two or more elements. In particular, considering corrosion resistance when used in a corrosive environment, it is preferable that one or more elements selected from Zn, Ni, Co, Mn, Cr, V, Zr, Sn, Ti, and B are contained.

[0038] <Ti: 0.00 mass% or more and 2.00 mass% or less> Ti is an element that has the effect of refining crystal grains during casting, reducing the number of specific voids, and further improving heat resistance and corrosion resistance when used in a corrosive environment. To sufficiently exert the effect of refining crystal grains during casting and improving heat resistance, the Ti content is preferably 0.005 mass% or more. In addition to this, to sufficiently exert the effect of improving corrosion resistance when used in a corrosive environment, the Ti content is more preferably 0.06 mass% or more, and even more preferably 0.30 mass% or more. On the other hand, when the Ti content exceeds 2.000 mass%, the workability deteriorates. Therefore, the Ti content is preferably 2.000 mass% or less, more preferably 1.500 mass% or less, and even more preferably 1.200 mass% or less. Note that since Ti is an optional additive element component, when Ti is not added, considering the content of impurities, the lower limit value of the Ti content is 0.00 mass%.

[0039] <B: 0.00 mass% or more and 2.00 mass% or less> B is an element that has the effect of refining crystal grains during casting, reducing the number of specific voids, and further improving heat resistance and corrosion resistance when used in a corrosive environment. To sufficiently exert the effect of refining crystal grains during casting and improving heat resistance, the B content is preferably 0.005 mass% or more. In addition to this, to sufficiently exert the effect of improving corrosion resistance when used in a corrosive environment, the B content is more preferably 0.06 mass% or more, and even more preferably 0.30 mass% or more. On the other hand, when the B content exceeds 2.000 mass%, the workability deteriorates. Therefore, the B content is preferably 2.000 mass% or less, more preferably 1.500 mass% or less, and even more preferably 1.200 mass% or less. Note that since B is an optional additive element component, when B is not added, considering the content of impurities, the lower limit value of the B content is 0.00 mass%.

[0040] <Cu: 0.00 mass% or more and 2.00 mass% or less> Cu is an element that has the effect of refining crystal grains during casting, reducing the number of specific voids, and further improving heat resistance. To fully exhibit such an effect, the content of Cu is preferably 0.02% by mass or more, and more preferably 0.30% by mass or more. On the other hand, when the content of Cu exceeds 2.00% by mass, the workability deteriorates and the corrosion resistance deteriorates. Therefore, the content of Cu is preferably 2.00% by mass or less, more preferably 1.50% by mass or less, and even more preferably 1.20% by mass or less. Note that since Cu is an optional additive element component, when Cu is not added, the lower limit value of the Cu content is 0.00% by mass in consideration of the content of impurities.

[0041] <Ag: 0.00% by mass or more and 2.00% by mass or less> Ag is an element that has the effect of refining crystal grains during casting, reducing the number of specific voids, and further improving heat resistance. To fully exhibit such an effect, the content of Ag is preferably 0.02% by mass or more, and more preferably 0.30% by mass or more. On the other hand, when the content of Ag exceeds 2.00% by mass, the workability deteriorates. Therefore, the content of Ag is preferably 2.00% by mass or less, more preferably 1.50% by mass or less, and even more preferably 1.20% by mass or less. Note that since Ag is an optional additive element component, when Ag is not added, the lower limit value of the Ag content is 0.00% by mass in consideration of the content of impurities.

[0042] <Zn: 0.00% by mass or more and 2.00% by mass or less> Zn is an element that has the effect of refining crystal grains during casting, reducing the number of specific voids, and further improving heat resistance and corrosion resistance when used in a corrosive environment. In order to fully exhibit such an effect, it is preferable that the Zn content is 0.02% by mass or more, and more preferably 0.30% by mass or more. On the other hand, when the Zn content exceeds 2.00% by mass, the workability deteriorates. Therefore, the Zn content is preferably 2.00% by mass or less, more preferably 1.50% by mass or less, and still more preferably 1.20% by mass or less. Note that since Zn is an optional additive element component, when Zn is not added, the lower limit value of the Zn content is 0.00% by mass in consideration of the content of impurities.

[0043] <Ni: 0.00% by mass or more and 2.00% by mass or less> Ni is an element that has the effect of refining crystal grains during casting, reducing the number of specific voids, and further improving heat resistance and corrosion resistance when used in a corrosive environment. From the viewpoint of fully exhibiting such an effect, it is preferable that the Ni content is 0.02% by mass or more, and more preferably 0.30% by mass or more. On the other hand, when the Ni content exceeds 2.00% by mass, the workability deteriorates. Therefore, the Ni content is preferably 2.00% by mass or less, more preferably 1.50% by mass or less, and still more preferably 1.20% by mass or less. Note that since Ni is an optional additive element component, when Ni is not added, the lower limit value of the Ni content is 0.00% by mass in consideration of the content of impurities.

[0044] <Co: 0.00% by mass or more and 2.00% by mass or less> Co is an element that has the effect of refining crystal grains during casting, reducing the number of specific voids, and further improving heat resistance and corrosion resistance when used in a corrosive environment. To fully exhibit such an effect, the Co content is preferably 0.02% by mass or more, and more preferably 0.30% by mass or more. On the other hand, when the Co content exceeds 2.00% by mass, the workability deteriorates. Therefore, the Co content is preferably 2.00% by mass or less, more preferably 1.50% by mass or less, and still more preferably 1.20% by mass or less. Note that since Co is an optional additive element component, when Co is not added, the lower limit of the Co content is 0.00% by mass in consideration of the content of impurities.

[0045] <Au: 0.00% by mass or more and 2.00% by mass or less> Au is an element that has the effect of refining crystal grains during casting, reducing the number of specific voids, and further improving heat resistance. To fully exhibit such an effect, the Au content is preferably 0.02% by mass or more, and more preferably 0.30% by mass or more. On the other hand, when the Au content exceeds 2.00% by mass, the workability deteriorates. Therefore, the Au content is preferably 2.00% by mass or less, more preferably 1.50% by mass or less, and still more preferably 1.20% by mass or less. Note that since Au is an optional additive element component, when Au is not added, the lower limit of the Au content is 0.00% by mass in consideration of the content of impurities.

[0046] <Mn: 0.00% by mass or more and 2.00% by mass or less> Mn is an element that has the effect of refining crystal grains during casting, reducing the number of specific voids, and further improving heat resistance and corrosion resistance when used in a corrosive environment. To fully exhibit such an effect, the content of Mn is preferably 0.02% by mass or more, and more preferably 0.30% by mass or more. On the other hand, when the content of Mn exceeds 2.00% by mass, the workability deteriorates. Therefore, the content of Mn is preferably 2.00% by mass or less, more preferably 1.50% by mass or less, and still more preferably 1.20% by mass or less. Incidentally, since Mn is an optional additive element component, when Mn is not added, the lower limit value of the Mn content is 0.00% by mass in consideration of the content of impurities.

[0047] <Cr: 0.00% by mass or more and 2.00% by mass or less> Cr is an element that has the effect of refining crystal grains during casting, reducing the number of specific voids, and further improving heat resistance and corrosion resistance when used in a corrosive environment. To fully exhibit such an effect, the content of Cr is preferably 0.02% by mass or more, and more preferably 0.30% by mass or more. On the other hand, when the content of Cr exceeds 2.00% by mass, the workability deteriorates. Therefore, the content of Cr is preferably 2.00% by mass or less, more preferably 1.50% by mass or less, and still more preferably 1.20% by mass or less. Incidentally, since Cr is an optional additive element component, when Cr is not added, the lower limit value of the Cr content is 0.00% by mass in consideration of the content of impurities.

[0048] <V: 0.00% by mass or more and 2.00% by mass or less> V is an element that has the effect of refining crystal grains during casting, reducing the number of specific voids, and further improving heat resistance and corrosion resistance when used in a corrosive environment. To fully exhibit such an effect, the content of V is preferably 0.02% by mass or more, and more preferably 0.30% by mass or more. On the other hand, when the content of V exceeds 2.00% by mass, the workability deteriorates. Therefore, the content of V is preferably 2.00% by mass or less, more preferably 1.50% by mass or less, and still more preferably 1.20% by mass or less. Note that since V is an optional additive element component, when V is not added, the lower limit value of the V content is 0.00% by mass in consideration of the content of impurities.

[0049] <Zr: 0.00% by mass or more and 2.00% by mass or less> Zr is an element that has the effect of refining crystal grains during casting, reducing the number of specific voids, and further improving heat resistance and corrosion resistance when used in a corrosive environment. To fully exhibit such an effect, the content of Zr is preferably 0.02% by mass or more, and more preferably 0.30% by mass or more. On the other hand, when the content of Zr exceeds 2.00% by mass, the workability deteriorates. Therefore, the content of Zr is preferably 2.00% by mass or less, more preferably 1.50% by mass or less, and still more preferably 1.20% by mass or less. Note that since Zr is an optional additive element component, when Zr is not added, the lower limit value of the Zr content is 0.00% by mass in consideration of the content of impurities.

[0050] <Sn: 0.00% by mass or more and 2.00% by mass or less> Sn is an element that refines crystal grains during casting, reduces the number of specific voids, and improves heat resistance and corrosion resistance when used in a corrosive environment. To fully utilize these effects, the Sn content is preferably 0.02% by mass or more, and more preferably 0.30% by mass or more. On the other hand, if the Sn content exceeds 2.00% by mass, workability decreases. Therefore, the Sn content is preferably 2.00% by mass or less, more preferably 1.50% by mass or less, and even more preferably 1.20% by mass or less. Note that Sn is an optional element, so if Sn is not added, the lower limit of the Sn content is set to 0.00% by mass, taking into account the impurity level.

[0051] <Remainder: Aluminum and inevitable impurities> The remainder other than the above-mentioned components is Al and unavoidable impurities. The term "unavoidable impurities" refers to impurities that may be unavoidably present during the manufacturing process. Depending on their content, unavoidable impurities may also cause a decrease in the electrical conductivity of the aluminum alloy. Therefore, it is preferable to limit the content of unavoidable impurities to some extent, taking into account the decrease in electrical conductivity of the aluminum alloy caused by unavoidable impurities. Examples of unavoidable impurities include Bi (bismuth), Pb (lead), Ga (gallium), and Sr (strontium). The content of each of these elements is preferably 0.05% by mass or less for each element, and 0.15% by mass or less in total for each of the elements.

[0052] The metal material 1 of this embodiment is a metal material 1 used for spirally winding around a core material, particularly a core material 2 having a relatively small outer diameter (for example, 1.0 mm or less), to form a foil thread 3. For this reason, the metal material 1 has an average thickness of 0.005 mm or more and 0.500 mm or less, an average width of 0.10 mm or more and 2.00 mm or less, and a cross-sectional area measured in the width direction of the metal material 1 of 0.80 mm or less. 2 It is preferable that:

[0053] The foil thread 3 in the embodiment of the present invention is assumed to have a small outer diameter of, for example, 1.0 mm or less, so it is necessary to minimize the influence of the metal material 1 on the dimensions of the foil thread 3 and ensure the bending characteristics, i.e., ease of winding, of the metal material 1. Based on these considerations, in the embodiment of the present invention, the cross-sectional area of ​​the metal material 1 is set to 0.8 mm 2 The lower limit of the cross-sectional area of ​​the metal material 1 is not particularly limited, but is preferably 0.001 mm or less, taking into consideration that the metal material 1 can be wound without breaking during the production of foil yarn. 2 It is set to above.

[0054] Furthermore, since the metal material 1 of this embodiment was developed as a metal material used to form the foil thread 3, it must be wound around a core material primarily composed of fibers. The aluminum alloy material described in Patent Document 4 has a larger width and thickness than the metal material 1 of this embodiment. However, in order to wind the aluminum alloy material around a commercially available resin core material containing fibers, the width and thickness of the foil must be determined taking into account the diameter of the core material. The metal material 1 of this embodiment was developed with the intention of forming the foil thread 3 with a small outer diameter as described above, and the ranges of the thickness t and width W of the metal material 1 are specified. Specifically, the average thickness t of the metal material 1 is preferably 0.005 mm or more and 0.500 mm or less, and more preferably 0.005 mm or more and 0.250 mm or less. The average width W is preferably 0.10 mm or more and 2.00 mm or less, and more preferably 0.10 mm or more and 1.0 mm or less. The width W, thickness t, and cross-sectional area of ​​the metal material 1 can be calculated based on an image of the cross section of the metal material 1 photographed using, for example, an optical microscope or an electron microscope.

[0055] Since both ends of the metal material 1 form convex curved surfaces, the width W and thickness t were measured at five locations at 2.00 mm intervals along the longitudinal direction of the metal material 1, and the arithmetic average values ​​thereof are recorded as the width W and thickness t. Specifically, "average thickness" refers to the sum of the thickness t1 of the central portion 4 and the thickness t2 of each of the end portions 5, and then dividing the sum by the number of these to obtain the arithmetic average value, which is then calculated as the average value of the five locations along the longitudinal direction. Furthermore, "average width" refers to the average value of the width W of the five locations along the longitudinal direction.

[0056] In the metal material 1 of this embodiment, the ratio (t1 / t2 ratio) of the thickness t1 of the widthwise central portion 4 to the thickness t2 of the widthwise end portions 5 is set to be within the range of 1.05 to 1.20. If the average width W is less than 0.10 mm, the amount of metal material 1 wound around the core material 2 per unit length increases, which may increase the weight of the foil thread 3 per unit length and the material cost. On the other hand, if the average width W is greater than 2.00 mm, bending the foil thread 3 makes the metal material 1 wound around the core material 2 more likely to bend, which may cause so-called bending cracks in the metal material 1.

[0057] Furthermore, the metal material 1 according to the embodiment of the present invention preferably has a Vickers hardness HV of 90 or more and 250 or less. Vickers hardness is generally proportional to tensile strength. During wire drawing or a forming process in which the metal material 1 is wound around a core material 2 to form a foil thread 3, a certain tension is generated in the metal material 1. To prevent breakage due to this tension, a Vickers hardness of 90 or more is preferred. A Vickers hardness of 90 is equivalent to the hardness of copper-based and iron-based materials. Therefore, the metal material 1 according to the embodiment of the present invention has a hardness equal to or greater than that of copper-based and iron-based materials. The Vickers hardness of the metal material 1 is preferably 105 or more, more preferably 115 or more, even more preferably 130 or more, even more preferably 150 or more, and most preferably 220 or more. Furthermore, if the Vickers hardness exceeds 250, the metal material 1 may become unwound when wound onto a bobbin or the like, making it difficult to wind. The Vickers hardness is measured in accordance with the method specified in JIS Z2244-1:2020, and the tensile strength is measured in accordance with the method specified in JIS Z2241:2011.

[0058] Furthermore, the ratio of the outer diameter D of the core material 2 to the thickness t of the metal material 1 (D / t ratio) is set to a value greater than 1.0. If the D / t ratio is 1.0 or less, when the metal material 1 is wound around the core material 2, the bending diameter of the metal material 1 at the portion where the metal material 1 is wound around the core material 2 (hereinafter referred to as the bent portion) becomes small. As a result, the strain generated in the metal material 1 at the bent portion becomes large. In that case, shear bands or bending cracks may occur at the bent portion, which may become the starting point of fracture, and this is to be avoided.

[0059] [Core material] Next, the core material 2 constituting the foil yarn 3 of the present invention will be described. The core material 2 is wound around the metal material 1. The core material 2 is formed by bundling or twisting together multiple fibers made of, for example, a synthetic resin material, and is configured in a so-called solid or hollow wire shape. Examples of synthetic resin materials include polyolefin resins such as polyethylene and polypropylene, polyester resins, and polyurethane resins. The core material 2 may also be formed from high-strength fibers such as Kevlar (registered trademark) and Zylon (registered trademark), or fibers made of resins that harden or denature when exposed to heat or ultraviolet light. Alternatively, the core material 2 may be formed by impregnating thread-like or linear fibers with a thermosetting resin or a thermoplastic resin. Furthermore, the core material 2 may be formed from solder or flux formed into a thread shape. The core material 2 is not particularly limited as long as it is configured in a thread-like or linear shape around which the metal material 1 can be wound. For example, when the average width W of the metal material 1 is set to 0.10 mm or more and 2.00 mm or less, the outer diameter D of the core material 2 is preferably set to 0.02 mm or more and 4.0 mm or less so that the W / D ratio is greater than 0.5 and less than 5.0.

[0060] [Foil thread] Then, as shown in Figure 3, the foil thread 3 is formed by spirally winding the metal material 1 around the core material 2 thus constructed so as to form gaps 6 at regular intervals in the longitudinal or axial direction of the core material 2. The gaps 6 are the portions that will bend when an external force that causes bending deformation of the foil thread 3 is applied to the foil thread 3, and the size or width of the gaps 6 can be determined in advance by experiment. This also reduces the amount of metal material 1 wound around the core material 2, thereby reducing the weight of the foil thread 3 per unit length and cutting material costs.

[0061] Therefore, according to an embodiment of the present invention, the strength of the ribbon-shaped metal material 1 can be made approximately the same as that of a ribbon-shaped metal material for foil threads made of a copper-based material, an iron-based material, or the like, because the aluminum or aluminum alloy constituting the metal material 1 is processed to a large extent. Furthermore, as shown in FIG. 4 , the ratio of the thickness t1 of the central portion 4 to the thickness t2 of both end portions 5 (t1 / t2 ratio) is within the range of 1.05 to 1.20. Therefore, when the metal material 1 is spirally wound around the core material 2 to produce the foil thread 3, contact between the core material 2 and both end faces can be suppressed. Therefore, when the metal material 1 is wound around the core material 2, stress concentration at both end faces can be suppressed, thereby preventing or suppressing damage to the metal material 1.

[0062] Furthermore, because the W / D ratio is greater than 0.5 and less than 5.0, it is possible to prevent or suppress an excessive increase in the amount of the metal material 1 wound around the core material 2. As a result, it is possible to prevent or suppress an increase in the weight of the foil thread 3 per unit length and in material costs. Furthermore, it is possible to prevent or suppress an excessive decrease in the so-called bending diameter of the metal material 1 when winding the metal material 1 around the core material 2, thereby preventing or suppressing the occurrence of shear bands or so-called bending cracks in the metal material 1 during winding. Furthermore, when the foil thread 3 is bent, bending occurs mainly in the above-mentioned gap 6, so it is possible to prevent or suppress bending of the metal material 1 wound around the core material 2. As a result, it is possible to obtain a foil thread 3 that is resistant to damage even when repeatedly subjected to bending deformation by external force, is lightweight, and has low material costs.

[0063] [Metal material 1 manufacturing method] A method for manufacturing a metal material 1 according to an embodiment of the present invention will be described. In this embodiment of the present invention, a linear processing material, i.e., a rough wire, made of pure aluminum or an aluminum alloy having the above-described alloy composition is prepared, and the rough wire is subjected to wiredrawing and rolling to manufacture the metal material 1. The aluminum alloy constituting the rough wire is not particularly limited as long as it has the above-described alloy composition. That is, the rough wire may be, for example, an extruded material, an ingot material, a hot-rolled material, or a cold-rolled material. The rough wire is then subjected to wiredrawing to form a thin wire of a predetermined thickness. The wiredrawing may be, for example, a conventionally known wiredrawing process known as drawing or a wiredrawing process using a deformed die. Note that the method for manufacturing a metal material 1 according to an embodiment of the present invention does not involve the aging precipitation heat treatment that is conventionally performed before wiredrawing.

[0064] The degree of working η of the wiredrawing is preferably 5 or more, more preferably 6 or more, and even more preferably 7 or more. There is no particular upper limit to the degree of working η, but it is usually 15. The degree of working η is the logarithmic ratio of the cross-sectional area s1 of the rough wire before wiredrawing to the cross-sectional area s2 of the rough wire after wiredrawing (s1>s2), and can be expressed by the following formula (1). Machining degree η (dimensionless) = ln(s1 / s2) ·····(1)

[0065] In the manufacturing method of the metal material 1 according to the embodiment of the present invention, the wiredrawing processing ratio R is preferably 98.2% or more, and more preferably 99.8% or more. The processing ratio R can be expressed by the following formula (2) based on the above-mentioned cross-sectional areas s1 and s2. Machining rate R(%)={(s1-s2) / s1}×100 (2)

[0066] Next, the thin wire formed by the wiredrawing process is rolled into the ribbon shape described above. This rolling process may be conventional roll rolling, flat wire rolling, satellite mill rolling, or the like. The rolling process is performed so that the t1 / t2 ratio (t1 / t2) of the thickness t1 of the central portion 4 to the thickness t2 of the end portions 5 is 1.05 to 1.20, as described above. A t1 / t2 ratio (t1 / t2) of the thickness t2 of the end portions 5 of the central portion 4 of 1.05 or more is preferable for the rolling process to prevent defects such as cracks during the rolling process. The difference between the thickness t1 of the central portion 4 and the thickness t2 of the end portions 5 can be adjusted, for example, by appropriately modifying the shape of the mill rolls that crush the thin wire. Specifically, the portion of the mill roll that forms the central portion 4 is recessed relative to the portion that forms the end portions 5. Alternatively, when crushing the thin wire by passing it between a pair of rolls, pressure is applied to both sides of the central portion of the thin wire in the radial direction of the thin wire, more than to the central portion. By doing so, it is possible to form the metal material 1 in which the thickness of the central portion 4 is greater than that of the end portions 5 in the cross-sectional views shown in FIGS.

[0067] In the above-mentioned rolling process, the width expansion ratio S is preferably 1.4 to 6.0, more preferably 1.7 to 5.0, even more preferably 2.0 to 4.0, and most preferably 2.3 to 3.5. The width expansion ratio S can be expressed by the following formula (3), where W1 is the diameter of the thin wire after wiredrawing and W2 is the width of the ribbon-shaped thin wire after rolling. Width expansion ratio S=W2 / W1 (3)

[0068] Note that wire drawing may be performed after rolling. Essentially, it is sufficient that the ratio (t1 / t2) of the thickness t1 of the central portion 4 to the thickness t2 of the end portion 5 of the metal material 1 (t1 / t2) is within the above-mentioned range, and that a ribbon-shaped thin wire of the specified diameter or width is obtained. Furthermore, temper annealing may be performed after rolling or wire drawing to relieve residual stress and improve elongation. Temper annealing is preferably performed at a temperature of 50°C to 160°C and a holding time of 1 hour to 48 hours. If the treatment temperature is below 50°C, it is difficult to achieve the effects of releasing residual stress and improving elongation. If the treatment temperature exceeds 160°C, grain growth due to recovery and recrystallization occurs, tending to reduce strength. The conditions for such heat treatment can be adjusted appropriately depending on the type and amount of inevitable impurities and the solid solution / precipitation state of the aluminum alloy material used.

[0069] In the embodiment of the present invention, as described above, a high degree of processing is performed on the rough wire. As a result, a high-strength metal material 1 having a long ribbon shape can be obtained. The length of the metal material 1 is at least 10 m or more. There is no particular upper limit on the length of the metal material 1 during manufacturing, but considering workability, it is preferable to set it to about 6000 m.

[0070] [Application] The metal material 1 and foil thread 3 according to the embodiment of the present invention have strengths similar to those of ribbon-shaped foil thread metal materials and foil threads made of copper-based or iron-based materials, and can therefore be used in place of such foil thread metal materials and foil threads. Specifically, examples include twisted yarns or twisted wires made by twisting together at least two foil threads 3, or fabrics made by combining or knitting multiple foil threads 3. They can also be used in wearable devices such as clothing heaters, sensors attached to clothing, and cameras. Furthermore, the foil thread 3 according to the embodiment of the present invention can be used for conductive components such as electric wires and cables, conductive materials such as aluminum conductors and wiring, shielding materials, wearable products, windings for motors, linear magnets, myoelectric prosthetic hands and limbs, prepregs, and tinsel wire.

[0071] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, but includes all aspects encompassed by the concept of the present invention and the scope of the claims, and can be modified in various ways within the scope of the present invention.

[0072] [Example] The present invention will be described below based on examples. (Examples 1 to 6 and Comparative Examples 1 to 6) A rough wire of aluminum or aluminum alloy having the alloy composition shown in Table 1 was prepared and used to carry out the above-mentioned wire drawing and rolling processes to produce a ribbon-shaped metal material 1 having the t1 / t2 ratio, average thickness t, average width W, cross-sectional area S, tensile strength, and Vickers hardness shown in Table 1. Then, as shown in Figure 3, the metal material 1 was spirally wound around a core material 2 made of aramid fiber with an outer diameter of 0.06 mm to produce a foil thread 3.

[0073] [Performance evaluation method] <Method for evaluating the presence or absence of line breakage> When the foil thread 3 was produced, the presence or absence of wire breakage was evaluated by observing whether or not breakage occurred in the metal material 1.

[0074] <Method for evaluating the presence or absence of shear bands> The surface of the metal material 1 wound around the core material 2 was observed under an optical microscope or an electron microscope at a magnification of about 300 times to evaluate the presence or absence of shear band formation.

[0075] [Table 1]

[0076] [evaluation] As shown in Table 1, in all of Examples 1 to 6, no linear breakage or shear band formation was observed in the metal material 1 constituting the foil yarn 3.

[0077] In contrast, in Comparative Examples 1 and 2, the tensile strength was outside the appropriate range of the present invention, and therefore linear fracture occurred in the metal material 1.

[0078] In Comparative Examples 3 and 4, the t1 / t2 ratio and the tensile strength were outside the appropriate ranges of the present invention, and therefore, linear fracture occurred in the metal material 1.

[0079] In Comparative Example 5, the t1 / t2 ratio was greater than the appropriate range of the present invention, and therefore not only did linear fractures occur in the metal material 1, but the formation of shear bands was also observed. Note that, in Comparative Example 3, similar to Comparative Example 5, the t1 / t2 ratio was greater than the appropriate range of the present invention, but the tensile strength was smaller than the appropriate range of the present invention and the material was softer, so no shear bands were formed.

[0080] In Comparative Example 6, the t1 / t2 ratio was smaller than the appropriate range of the present invention, and therefore, linear fracture occurred in the metal material 1. [Explanation of symbols]

[0081] 1 Metal material 2 Core material 3. Foil thread 4 Center part in width direction 5 Width end 6. Gap

Claims

1. A metal material for foil threads having a ribbon shape that is spirally wound around a thread-like core material to form a foil thread, The metal material is Made of aluminum or an aluminum alloy, The metal material has a width direction cross section that is substantially rectangular, and When viewed in a width direction cross section of the metal material, the thickness of the width direction central portion is 1.05 times or more and 1.20 times or less the thickness of the width direction end portion, The tensile strength is 270 MPa or more and 750 MPa or less, The average thickness is 0.005 mm or more and 0.500 mm or less, The average width is 0.10 mm or more and 2.00 mm or less, and The metal material for foil threads is characterized in that the cross-sectional area measured in the width direction is 0.80 mm 2 or less.

2. The aluminum alloy has an alloy composition containing 0.10% by mass or more and 1.80% by mass or less of magnesium, 0.20% by mass or more and 2.10% by mass or less of silicon, 0.01% by mass or more and 2.00% by mass or less of iron, and the remainder being aluminum and inevitable impurities. The metal material for foil thread according to claim 1.

3. The aluminum alloy contains 0.10% by mass or more and 1.80% by mass or less of magnesium, 0.20% by mass or more and 2.10% by mass or less of silicon, and 0.01% by mass or more and 2.00% by mass or less of iron, and further contains 0.02% by mass or more and 2.00% by mass or less of at least one component selected from the group consisting of titanium, boron, copper, silver, zinc, nickel, cobalt, gold, manganese, chromium, vanadium, zirconium, and tin, in a total amount of 0.02% by mass or more and 2.00% by mass or less, with the remainder being aluminum and unavoidable impurities. The metal material for foil yarn according to claim 1, having an alloy composition consisting of:

4. A foil thread formed by spirally winding the metal material for foil thread according to any one of claims 1 to 3 around the core material.

5. The foil yarn according to claim 4, wherein the ratio (W / D) of the width (W) of the metal material to the outer diameter (D) of the core material is greater than 0.5 and less than 5.

0.

6. A twisted yarn formed by twisting together at least two or more foil yarns according to claim 5.

7. A cloth formed by combining a plurality of the foil yarns according to claim 5.

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