Aluminum alloy, aluminum alloy wire, and method of manufacturing aluminum alloy wire

Abstract

The aluminum alloy has a composition comprising 0.6 mass% or more and 1.5 mass% or less of silicon, 0.5 mass% or more and 1.3 mass% or less of magnesium, 0.1 mass% or more and 1.2 mass% or less of copper, and 0.2 mass% or more and 1.15 mass% or less of manganese, with the remainder being aluminum and unavoidable impurities, and in a state where solution treatment and aging treatment are performed, the average value of the orientation of the 111 planes obtained by X-ray diffraction of the entire cross-section is 50% or more, and the dispersion of the orientation of the 111 planes is 45% or less.

Description

Technology Field

[0001] The present disclosure relates to an aluminum alloy, an aluminum alloy wire, and a method for manufacturing an aluminum alloy wire.

[0002] The present application claims priority based on Japanese patent application No. 2021-089504 of May 27, 2021, and incorporates all contents described in said Japanese application. Background Technology

[0003] Patent Document 1 discloses an aluminum alloy wire having high tensile strength after solution treatment and aging treatment, as a wire rod comprising an aluminum alloy containing silicon and magnesium. The aluminum alloy wire can be used as a raw material for an aluminum alloy member. The aluminum alloy member is manufactured by performing solution treatment and aging treatment after a predetermined plastic processing is performed on the aluminum alloy wire. Prior art literature

[0004] Patent Document 1: Japanese Patent Publication No. 2015-124409 The problem to be solved

[0005] The aluminum alloy of the present disclosure has a composition comprising 0.6 mass% or more and 1.5 mass% or less of silicon, 0.5 mass% or more and 1.3 mass% or less of magnesium, 0.1 mass% or more and 1.2 mass% or less of copper, and 0.2 mass% or more and 1.15 mass% or less of manganese, with the remainder being aluminum and unavoidable impurities. In a state where solution treatment and aging treatment have been performed, the average value of the orientation of the 111 planes obtained by X-ray diffraction over the entire cross-section is 50% or more, and the dispersion of the orientation of the 111 planes is 45% or less.

[0006] The aluminum alloy wire of the present disclosure comprises the aluminum alloy of the present disclosure.

[0007] The method for manufacturing an aluminum alloy wire according to the present disclosure comprises: a process of manufacturing a processed material by performing plastic processing on a cast aluminum alloy having a composition comprising 0.6 mass% or more and 1.5 mass% or less of silicon, 0.5 mass% or more and 1.3 mass% or less of magnesium, 0.1 mass% or more and 1.2 mass% or less of copper, and 0.2 mass% or more and 1.15 mass% or less of manganese, with the remainder comprising aluminum and unavoidable impurities; a process of manufacturing a first drawn material by performing a first cold drawing process on the processed material; a process of manufacturing a softened material by performing a softening treatment on the first drawn material; and a process of manufacturing a second drawn material by performing a second cold drawing process on the softened material. The degree of processing in the second drawing process is 20% or more and is greater than the degree of processing in the first drawing process. Brief explanation of the drawing

[0008] FIG. 1 is a perspective view illustrating an example of an aluminum alloy wire of an embodiment. FIG. 2 is a diagram illustrating an example of the distribution of the orientation degree of 111 planes with respect to the cross-section of the aluminum alloy wire of Sample No. 3 of Test Example 1. Figure 3 is a diagram showing an example of the distribution of the orientation degree of 111 planes for the aluminum alloy wire of Sample No. 3 of Test Example 1 using contour lines. Figure 4 is a diagram illustrating an example of the distribution of the orientation degree of 111 planes with respect to the cross-section of the aluminum alloy wire of Sample No. 1 of Test Example 1. FIG. 5 is a diagram showing an example of the distribution of the orientation degree of 111 planes for the aluminum alloy wire of Sample No. 1 of Test Example 1 using contour lines. Figure 6 is a diagram illustrating a method for measuring the distribution of the orientation of 111 planes over the entire cross-section of a sample. Specific details for implementing the invention

[0009] [Problems to be solved by the present disclosure]

[0010] As mentioned above, further improvement in strength is desired for aluminum alloy components used after solution treatment and aging treatment. In addition, an aluminum alloy capable of forming such high-strength aluminum alloy components is desired.

[0011] Therefore, one of the objectives of the present disclosure is to provide a high-strength aluminum alloy in a state where solution treatment and aging treatment have been performed. Another objective of the present disclosure is to provide an aluminum alloy wire comprising the said aluminum alloy. Another objective of the present disclosure is to provide a method for manufacturing an aluminum alloy wire capable of manufacturing the said aluminum alloy wire.

[0012] [Effects of the present disclosure]

[0013] The aluminum alloy of the present disclosure and the aluminum alloy wire of the present disclosure have high strength when solution treatment and aging treatment are performed. The method for manufacturing the aluminum alloy wire of the present disclosure can manufacture the aluminum alloy wire of the present disclosure.

[0014] [Description of embodiments of the present disclosure]

[0015] For the first time, embodiments of the present disclosure are described in detail.

[0016] (1) An aluminum alloy according to one embodiment of the present disclosure has a composition comprising 0.6 mass% or more and 1.5 mass% or less of silicon, 0.5 mass% or more and 1.3 mass% or less of magnesium, 0.1 mass% or more and 1.2 mass% or less of copper, 0.2 mass% or more and 1.15 mass% or less of manganese, with the remainder being aluminum and unavoidable impurities. In this aluminum alloy, the average value of the orientation of the 111 planes obtained by X-ray diffraction of the entire cross-section in a state in which solution treatment and aging treatment are performed is 50% or more, and the dispersion of the orientation of the 111 planes is 45% or less.

[0017] In the present disclosure, the 111 plane refers to a crystal plane denoted as (111) in crystallography. The orientation of the 111 plane in the present disclosure is obtained by using the normalized values ​​of the following three diffraction intensities obtained by X-ray diffraction over the entire cross-section. The orientation of the 111 plane in the present disclosure is the ratio of the normalized value of the diffraction intensity of the 111 plane to the sum of the three normalized values. The three diffraction intensities are the diffraction intensity of the 111 plane, the diffraction intensity of the 200 plane, and the diffraction intensity of the 220 plane. The 200 plane and the 220 plane refer to crystal planes denoted as (200) and (220) in crystallography. The average value of the orientation of the 111 plane in the present disclosure is the average of the aforementioned ratios at each measurement point over the entire cross-section. The variance of the orientation of the 111 plane in the present disclosure is the value obtained from the average value. A method for measuring the average value and variance of the orientation degree of 111 planes in the present disclosure is described below. The measurement method described below can appropriately evaluate the orientation degree of 111 planes across the entire cross-section by making the entire cross-section the target of X-ray diffraction measurement and by specifying the orientation state of 111 planes using a value normalized from the diffraction intensity.

[0018] In the present disclosure, the cross-section of the aluminum alloy is, for example, the following cross-section. When the aluminum alloy has a somewhat long shape, such as a wire, pipe, or plate, the cross-section is a cross-section obtained by cutting with a plane perpendicular to the longitudinal direction of the aluminum alloy.

[0019] In the present disclosure, the conditions for solution treatment and aging treatment are as follows.

[0020] (Conditions for solution treatment)

[0021] The heating temperature is a temperature selected from a range of 530°C or higher and 580°C or lower. The heating time is a time selected from a range of 15 minutes or higher and 120 minutes or lower.

[0022] (Conditions for processing the statute of limitations)

[0023] The heating temperature is a temperature selected from a range of 150°C or higher and 180°C or lower. The heating time is a time selected from a range of 4 hours or higher and 100 hours or lower.

[0024] The aluminum alloy of the present disclosure, by having the specific composition described above, possesses high tensile strength due to precipitation hardening when solution treatment and aging treatment are performed. In particular, in the aluminum alloy of the present disclosure, the orientation of the 111 planes of the crystal grains occurs throughout the entire cross-section, not just in a part of the cross-section. The aluminum alloy of the present disclosure having such a cross-section is difficult to fracture when, for example, the direction perpendicular to this cross-section is the tensile direction. In this respect as well, the aluminum alloy of the present disclosure possesses high tensile strength. Preferably, the aluminum alloy of the present disclosure has higher tensile strength than the aluminum alloy described in Patent Document 1. In the above respects, the aluminum alloy of the present disclosure is high strength when solution treatment and aging treatment are performed.

[0025] Furthermore, when the aluminum alloy of the present disclosure is subjected to solution treatment and aging treatment, it possesses a good balance of heat resistance, corrosion resistance, and strength, similar to the alloy known as the 6000 series alloy by international alloy symbol. This aluminum alloy of the present disclosure can be suitably used as a raw material for aluminum alloy members or aluminum alloy members requiring even higher strength in addition to heat resistance and corrosion resistance. Aluminum alloy members are, for example, automotive parts or various structural members. Automotive parts or various structural members may take the form of wires, rods, pipes, etc. The above raw materials are, for example, aluminum alloy wires or aluminum alloy plates.

[0026] (2) The aluminum alloy of the present disclosure may also include one or more elements selected from the group consisting of iron, chromium, zinc, titanium, and zirconium. The iron content is greater than 0 mass% and less than or equal to 0.8 mass%. The chromium content is greater than 0 mass% and less than or equal to 0.35 mass%. The zinc content is greater than 0 mass% and less than or equal to 0.5 mass%. The titanium content is greater than 0 mass% and less than or equal to 0.2 mass%. The zirconium content is greater than 0 mass% and less than or equal to 0.2 mass%.

[0027] The above-mentioned aluminum alloy is likely to have higher tensile strength.

[0028] (3) The aluminum alloy of (2) above may have a composition comprising 1.0 mass% or more and 1.3 mass% or less of silicon, 0.5 mass% or more and 1.2 mass% or less of magnesium, 0.3 mass% or more and 0.8 mass% or less of iron, 0.1 mass% or more and 0.4 mass% or less of copper, 0.2 mass% or more and 0.5 mass% or less of manganese, more than 0 mass% and 0.3 mass% or less of chromium, 0.001 mass% or more and 0.1 mass% or less of titanium, with the remainder being aluminum and unavoidable impurities. This aluminum alloy may also contain 0.001 mass% or more and 0.2 mass% or less of zirconium.

[0029] The above-mentioned aluminum alloy is likely to have higher tensile strength.

[0030] (4) The aluminum alloy of (2) above may have a composition comprising 0.6 mass% or more and 1.5 mass% or less of silicon, 0.7 mass% or more and 1.3 mass% or less of magnesium, 0.02 mass% or more and 0.4 mass% or less of iron, 0.5 mass% or more and 1.2 mass% or less of copper, 0.5 mass% or more and 1.1 mass% or less of manganese, more than 0 mass% and 0.3 mass% or less of chromium, 0.005 mass% or more and 0.5 mass% or less of zinc, 0.01 mass% or more and 0.2 mass% or less of titanium, and 0.05 mass% or more and 0.2 mass% or less of zirconium, with the remainder being aluminum and unavoidable impurities.

[0031] The above-mentioned aluminum alloy is likely to have higher tensile strength.

[0032] (5) The aluminum alloy of the present disclosure may have a tensile strength of more than 425 MPa when solution treatment and aging treatment are performed.

[0033] The aforementioned aluminum alloy is high-strength due to its high tensile strength.

[0034] (6) An aluminum alloy wire according to one embodiment of the present disclosure comprises an aluminum alloy described in any one of (1) to (5).

[0035] The aluminum alloy wire of the present disclosure has high strength when solution treatment and aging treatment are performed by including the aluminum alloy of the present disclosure. Such an aluminum alloy wire of the present disclosure can be used as a raw material for high-strength aluminum alloy members.

[0036] (7) A method for manufacturing an aluminum alloy wire according to one embodiment of the present disclosure comprises: a process of manufacturing a processed material by performing plastic processing on a cast aluminum alloy having a composition comprising 0.6 mass% or more and 1.5 mass% or less of silicon, 0.5 mass% or more and 1.3 mass% or less of magnesium, 0.1 mass% or more and 1.2 mass% or less of copper, and 0.2 mass% or more and 1.15 mass% or less of manganese, with the remainder being aluminum and unavoidable impurities; a process of manufacturing a first drawn material by performing a first cold drawing process on the processed material; a process of manufacturing a softened material by performing a softening treatment on the first drawn material; and a process of manufacturing a second drawn material by performing a second cold drawing process on the softened material. The degree of processing in the second drawing process is 20% or more and is greater than the degree of processing in the first drawing process.

[0037] The method for manufacturing an aluminum alloy wire according to the present disclosure can produce a high-strength aluminum alloy wire in a state where solution treatment and aging treatment have been performed. The reason for this will be explained later.

[0038] (8) In the method for manufacturing an aluminum alloy wire of the present disclosure, the aluminum alloy may also include one or more elements selected from the group consisting of iron, chromium, zinc, titanium, and zirconium. The iron content is greater than 0 mass% and less than or equal to 0.8 mass%. The chromium content is greater than 0 mass% and less than or equal to 0.35 mass%. The zinc content is greater than 0 mass% and less than or equal to 0.5 mass%. The titanium content is greater than 0 mass% and less than or equal to 0.2 mass%. The zirconium content is greater than 0 mass% and less than or equal to 0.2 mass%.

[0039] The above-described method for manufacturing an aluminum alloy wire can produce an aluminum alloy wire having higher tensile strength.

[0040] [Details of embodiments of the present disclosure]

[0041] Hereinafter, embodiments of the present disclosure will be described in detail with appropriate reference to the drawings.

[0042] [Aluminum Alloy]

[0043] (outline)

[0044] The aluminum alloy of the embodiment has the following composition and the following cross-sectional structure. The composition of the aluminum alloy of the embodiment includes silicon, magnesium, copper, and manganese within the ranges described below, respectively, and the remainder includes aluminum and unavoidable impurities. The aluminum alloy of the embodiment may also include one or more elements selected from the group consisting of iron, chromium, zinc, titanium, and zirconium within the range described below. In the cross-sectional structure of the aluminum alloy of the embodiment, the 111 planes of the crystal grains are oriented in the direction normal to the cross section when solution treatment and aging treatment are performed. In particular, the 111 planes are oriented in the direction normal to the cross section for most of the crystal grains constituting the cross section of the aluminum alloy. The composition and structure will be described in order below.

[0045] In the following description, there are cases where it is written as follows.

[0046] Silicon, magnesium, copper, and manganese are combined and referred to as the first element. Iron, chromium, zinc, titanium, and zirconium are combined and referred to as the second element.

[0047] Each element is represented by its element symbol. Si stands for silicon. Mg stands for magnesium. Cu stands for copper. Mn stands for manganese. Al stands for aluminum. Fe stands for iron. Cr stands for chromium. Zn stands for zinc. Ti stands for titanium. Zr stands for zirconium.

[0048] The state of an aluminum alloy after solution treatment and aging treatment is referred to as the state after heat treatment.

[0049] (furtherance)

[0050] In the aluminum alloy of the embodiment, the first element is an essential element, and the second element is an optional element. Quantitatively, the aluminum alloy of the embodiment has a composition comprising silicon at 0.6 mass% or more and 1.5 mass% or less, magnesium at 0.5 mass% or more and 1.3 mass% or less, copper at 0.1 mass% or more and 1.2 mass% or less, manganese at 0.2 mass% or more and 1.15 mass% or less, iron at 0 mass% or more and 0.8 mass% or less, chromium at 0 mass% or more and 0.35 mass% or less, zinc at 0 mass% or more and 0.5 mass% or less, titanium at 0 mass% or more and 0.2 mass% or less, zirconium at 0 mass% or more and 0.2 mass% or less, with the remainder being aluminum and unavoidable impurities. In the aluminum alloy of the embodiment containing one or more second elements, the iron content is greater than 0 mass% and less than or equal to 0.8 mass%. The chromium content is greater than 0 mass% and less than or equal to 0.35 mass%. The zinc content is greater than 0 mass% and less than or equal to 0.5 mass%. The titanium content is greater than 0 mass% and less than or equal to 0.2 mass%. The zirconium content is greater than 0 mass% and less than or equal to 0.2 mass%.

[0051] Since the content ratio of the first element is greater than or equal to the aforementioned lower limit, compounds containing the first element are precipitated in the state after heat treatment. As the precipitates of the aforementioned compounds exist in a dispersed manner, an effect of strength improvement through precipitation hardening is obtained. If a portion of the first element is dissolved in aluminum, which is the main component of the matrix phase, an effect of strength improvement through solid solution strengthening is also obtained. Since the content ratio of the first element is less than or equal to the aforementioned upper limit, grain boundary embrittlement caused by the segregation of the first element is suppressed, or it becomes difficult for compounds containing the first element to coarse. Particles of coarse compounds can serve as crack initiation points. If the aforementioned coarse particles are few, it is difficult for cracks caused by said coarse particles to occur. In these respects, the aluminum alloy of the embodiment has high tensile strength in the state after heat treatment. During the manufacturing process, since cracks caused by said coarse particles are difficult to occur, cold plastic processing such as cold drawing can be performed well. In this respect, the aluminum alloy of the embodiment also has excellent manufacturability.

[0052] When a second element is included in addition to the first element, one or more effects selected from the group consisting of precipitation hardening, solid solution strengthening, suppression of intergranular embrittlement, and suppression of grain coarsening can be expected. Due to these effects, the aluminum alloy of the embodiment containing the second element in addition to the first element is likely to have higher tensile strength in the state after heat treatment. By satisfying the aforementioned upper limit range for the content ratio of the second element, it is difficult for compounds containing the second element to coarsen. Furthermore, depending on the type of the second element, the cast material can have a fine structure. In these respects, the aluminum alloy of the embodiment containing the second element in addition to the first element has excellent workability when plastic deformation is included in the manufacturing process. Depending on the type of the second element, the pouring temperature can be lowered. In these respects, the aluminum alloy of the embodiment containing the second element in addition to the first element has superior manufacturability.

[0053] Specific examples of a composition including a second element in addition to a first element include the following first composition, second composition, and third composition.

[0054] 〈First Composition〉

[0055] The first composition comprises silicon at 1.0 mass% or more and 1.3 mass% or less, magnesium at 0.5 mass% or more and 1.2 mass% or less, iron at 0.3 mass% or more and 0.8 mass% or less, copper at 0.1 mass% or more and 0.4 mass% or less, manganese at 0.2 mass% or more and 0.5 mass% or less, chromium at more than 0 mass% and 0.3 mass% or less, titanium at 0.001 mass% or more and 0.1 mass% or less, zirconium at 0 mass% or more and 0.2 mass% or less, and the remainder comprises aluminum and unavoidable impurities.

[0056] 〈Second Composition〉

[0057] The second composition comprises silicon in an amount of 0.6 mass% or more and 1.5 mass% or less, magnesium in an amount of 0.7 mass% or more and 1.3 mass% or less, iron in an amount of 0.02 mass% or more and 0.4 mass% or less, copper in an amount of 0.5 mass% or more and 1.2 mass% or less, manganese in an amount of 0.5 mass% or more and 1.1 mass% or less, chromium in an amount greater than 0 mass% and 0.3 mass% or less, zinc in an amount of 0.005 mass% or more and 0.5 mass% or less, titanium in an amount of 0.01 mass% or more and 0.2 mass% or less, zirconium in an amount of 0.05 mass% or more and 0.2 mass% or less, and the remainder comprises aluminum and unavoidable impurities. The second composition may also comprise strontium in an amount of 0.005 mass% or more and 0.05 mass% or less.

[0058] 〈Third Composition〉

[0059] The third composition comprises silicon in an amount of 0.9 mass% or more and 1.3 mass% or less, magnesium in an amount of 0.8 mass% or more and 1.2 mass% or less, iron in an amount of more than 0 mass% and 0.4 mass% or less, copper in an amount of 0.65 mass% or more and 1.1 mass% or less, manganese in an amount of 0.55 mass% or more and 1.15 mass% or less, chromium in an amount of more than 0 mass% and 0.35 mass% or less, zinc in an amount of 0.12 mass% or more and 0.25 mass% or less, titanium in an amount of more than 0 mass% and 0.075 mass% or less, zirconium in an amount of 0.05 mass% or more and 0.17 mass% or less, and the remainder comprises aluminum and unavoidable impurities. The third composition is approximately equivalent to the composition of the alloy represented by the international alloy symbol A6056.

[0060] Hereinafter, the content range of the first element and the content range of the second element in the first, second, and third compositions are exemplified.

[0061] 〈First Composition〉

[0062] The silicon content may be greater than 1.0 mass% and less than or equal to 1.3 mass%, or greater than or equal to 1.1 mass% and less than or equal to 1.3 mass%.

[0063] The magnesium content may be 0.6 mass% or more and 1.1 mass% or less, or 0.7 mass% or more and 1.0 mass% or less.

[0064] The iron content may be 0.3 mass% or more and 0.7 mass% or less, or 0.3 mass% or more and 0.6 mass% or less.

[0065] The copper content may be 0.2 mass% or more and 0.4 mass% or less.

[0066] The manganese content may be 0.2 mass% or more and 0.4 mass% or less, or 0.2 mass% or more and 0.3 mass% or less.

[0067] The chromium content may be 0.005 mass% or more and 0.20 mass% or less, or 0.01 mass% or more and 0.10 mass% or less.

[0068] The titanium content may be 0.005 mass% or more and 0.05 mass% or less, or 0.01 mass% or more and 0.05 mass% or less.

[0069] In the case of containing zirconium, the zirconium content may be 0.001 mass% or more and 0.20 mass% or less, or 0.005 mass% or more and 0.10 mass% or less.

[0070] The total content ratio of titanium and zirconium may be 0.01 mass% or more and 0.10 mass% or less.

[0071] 〈Second Composition〉

[0072] The silicon content may be 0.8 mass% or more and 1.4 mass% or less, or 1.1 mass% or more and 1.3 mass% or less.

[0073] The magnesium content may be 0.8 mass% or more and 1.3 mass% or less, or 0.8 mass% or more and 1.0 mass% or less.

[0074] The iron content may be 0.05 mass% or more and 0.40 mass% or less.

[0075] The copper content may be 0.8 mass% or more and 1.2 mass% or less.

[0076] The manganese content may be 0.7 mass% or more and 1.1 mass% or less.

[0077] The chromium content may be 0.01 mass% or more and 0.30 mass% or less, or 0.05 mass% or more and 0.30 mass% or less.

[0078] The zinc content may be 0.05 mass% or more and 0.25 mass% or less.

[0079] The titanium content may be 0.01 mass% or more and 0.15 mass% or less.

[0080] The zirconium content may be 0.08 mass% or more and 0.2 mass% or less.

[0081] The total content ratio of titanium and zirconium may be 0.10 mass% or more and 0.20 mass% or less.

[0082] In the case of containing strontium, the strontium content may be 0.005 mass% or more and 0.04 mass% or less.

[0083] 〈Third Composition〉

[0084] The silicon content may be 0.9 mass% or more and 1.2 mass% or less.

[0085] The magnesium content may be 0.8 mass% or more and 1.0 mass% or less.

[0086] The iron content may be 0.10 mass% or more and 0.25 mass% or less.

[0087] The copper content may be 0.65 mass% or more and 0.85 mass% or less.

[0088] The manganese content may be 0.55 mass% or more and 0.80 mass% or less, or 0.55 mass% or more and 0.65 mass% or less.

[0089] The chromium content may be 0.01 mass% or more and 0.10 mass% or less, or 0.02 mass% or more and 0.05 mass% or less.

[0090] The zinc content may be 0.13 mass% or more and 0.25 mass% or less.

[0091] The titanium content may be 0.001 mass% or more and 0.075 mass% or less, or 0.01 mass% or more and 0.075 mass% or less.

[0092] The zirconium content may be 0.10 mass% or more and 0.17 mass% or less.

[0093] The total content ratio of titanium and zirconium may be 0.11 mass% or more and 0.20 mass% or less.

[0094] Other Elements

[0095] In the case of including titanium, the aluminum alloy of the embodiment may also include boron in a range of 50 mass ppm or less.

[0096] (group)

[0097] The inventors have found that it is desirable for an aluminum alloy having high tensile strength in the state after heat treatment to have the following microstructure. It is desirable that the 111 planes of the grains are oriented more than other planes in the grains across the entire cross-section of the aluminum alloy. That is, it is desirable that the 111 planes are oriented in most of the grains among the grains constituting the cross-section of the aluminum alloy. Quantitatively, in the aluminum alloy of the embodiment, the average value of the degree of orientation of the 111 planes obtained by X-ray diffraction across the entire cross-section in the state after heat treatment is 50% or more. Furthermore, the dispersion of the degree of orientation of the 111 planes is 45% or less. An aluminum alloy having multiple such cross-sections and arranged in a direction perpendicular to a single cross-section is difficult to fracture even when subjected to tension with the perpendicular direction as the tensile direction.

[0098] If the average value of the orientation degree of the 111 planes is 50% or more, the 111 planes are oriented in the direction normal to the cross-section in more than half of the grains constituting the cross-section of the aluminum alloy. If the dispersion of the orientation degree of the 111 planes is 45% or less, the distribution of oriented crystal planes among the grains constituting the cross-section of the aluminum alloy becomes a distribution concentrated on the 111 planes. The aluminum alloy of this embodiment has a high orientation of the 111 planes of the grains. In general, the tensile strength of an aluminum alloy tends to increase as the orientation of the 111 planes of the grains increases. Therefore, the aluminum alloy of this embodiment has high tensile strength in the state after heat treatment. The tensile strength tends to increase as the average value of the orientation degree of the 111 planes increases and as the dispersion of the orientation degree of the 111 planes decreases. In terms of improving strength, the average value of the orientation of the 111 planes may be 55% or more, and furthermore, 60% or more. The variance of the orientation of the 111 planes may be 40% or less, and furthermore, 38% or less.

[0099] In addition, the average value of the orientation of the 111 planes is 50% or more and 100% or less. The variance of the orientation of the 111 planes is greater than 0% and less than or equal to 45%. Considering manufacturability, the average value of the orientation of the 111 planes may be 99% or less, and the variance of the orientation of the 111 planes may be 1% or more.

[0100] In the aluminum alloy of the embodiment, the orientation of the 111 planes of the crystal grains is evaluated over the entire cross-section, not just a part of the cross-section. In this respect, the aluminum alloy of the embodiment certainly has a higher strength structure than when only a part of the cross-section is evaluated in the state after heat treatment.

[0101] In the case where the aluminum alloy of the embodiment is a wire, the cross-section subjected to measuring the orientation degree of the 111 planes is a cross-section cut with a plane perpendicular to the length direction at any position along the length direction of the wire. Hereinafter, a cross-section cut with a plane perpendicular to the length direction of the wire containing the aluminum alloy of the embodiment, i.e., the aluminum alloy wire (1) of the embodiment, may be represented as a cross-section. In the wire, the 111 planes of the crystal grains are oriented more than other crystal planes throughout each cross-section as described above. The orientation direction of the 111 planes in each cross-section is the normal direction of the cross-section, that is, the direction following the length direction of the wire. Such a wire is difficult to fracture even when subjected to tension with the length direction of the wire as the tension direction.

[0102] In addition, in the aluminum alloy of the embodiment, even when only solution treatment is performed and aging treatment is not performed, the average value of the orientation of the 111 planes is 50% or more, and the variance of the orientation of the 111 planes is 45% or less. That is, it is thought that the orientation of the 111 planes of the grains does not substantially change before and after aging treatment.

[0103] (tensile strength)

[0104] The aluminum alloy of the embodiment has a tensile strength of 425 MPa at room temperature, for example, in the state after heat treatment. Here, room temperature is 5°C or higher and 35°C or lower. The aluminum alloy of the embodiment with a tensile strength of 425 MPa or higher has excellent strength. The aluminum alloy of the embodiment with a tensile strength of 427 MPa or higher, 430 MPa or higher, and furthermore 440 MPa or higher has even better strength. Depending on the composition or manufacturing conditions, the aluminum alloy of the embodiment has a high tensile strength of 450 MPa or higher, 460 MPa or higher, and furthermore 470 MPa or higher.

[0105] There is no specific upper limit for tensile strength. Considering manufacturability, the tensile strength at room temperature may be, for example, greater than 425 MPa and less than or equal to 550 MPa.

[0106] (Usage type)

[0107] The aluminum alloy of the embodiment may have various shapes. For example, the aluminum alloy of the embodiment has a somewhat elongated shape. The aluminum alloy of such an embodiment has an end surface including a plane perpendicular to its length direction and an elongated portion extending in the length direction. The length along the length direction in the elongated portion is longer than the diameter of a circle having an area equal to the area of ​​the outer contour of the end surface. In the aluminum alloy of the embodiment having the elongated portion, the cross-section to which the orientation degree of the aforementioned 111 plane is measured is obtained by cutting the elongated portion with a plane perpendicular to the length direction.

[0108] The aluminum alloy of the embodiment having an elongated portion is, for example, a wire, a pipe, a plate, etc. That is, the elongated portion may be a solid body such as a wire or a plate, or a hollow body such as a pipe.

[0109] <Seonjae>

[0110] The aluminum alloy wire (1) of the embodiment comprises the aluminum alloy of the embodiment. The aluminum alloy wire (1) of the embodiment has an end surface (10) and an elongated portion (11) as shown in FIG. 1. The end surface (10) is a plane perpendicular to the longitudinal direction of the aluminum alloy wire (1). The elongated portion (11) extends in the longitudinal direction. The aluminum alloy wire (1) of the embodiment typically has a uniform outer contour and a uniform wire diameter over the entire length of the elongated portion (11), as shown in FIG. 1. The wire diameter here is the diameter of a circle having an area equal to the area of ​​the end surface (10) or the area of ​​a cross-section cut by a plane perpendicular to the longitudinal direction. FIG. 1 illustrates a case where the outer contour of the end surface (10) and the outer contour of any cross-section cut by a plane perpendicular to the longitudinal direction are circular. The outer contour of the end surface (10) and the outer contour of the cross section may be polygonal shapes such as squares or curved shapes such as ellipses. The wire diameter of the aluminum alloy wire (1) of the embodiment is not particularly required. The wire diameter is, for example, about 3 mm or more and 15 mm or less.

[0111] In the aluminum alloy wire (1) of the embodiment, the cross section to be measured for the orientation degree of the aforementioned 111 planes is a cross section. In the aluminum alloy wire (1) of the embodiment, the average value of the orientation degree of the 111 planes obtained by X-ray diffraction over the entire cross section is 50% or more. In addition, the dispersion of the orientation degree of the 111 planes is 45% or less. In the aluminum alloy wire (1) of the embodiment, such cross sections are arranged in the longitudinal direction. The aluminum alloy wire (1) of this embodiment has a high tensile strength of more than 425 MPa in the state after heat treatment.

[0112] Aluminum alloy component

[0113] The aluminum alloy of the embodiment may constitute an aluminum alloy member. For example, the aluminum alloy member comprises the aluminum alloy of the embodiment and has undergone solution treatment and aging treatment. A specific example is an aluminum alloy member in which solution treatment and aging treatment are performed after plastic processing is carried out on the aluminum alloy wire (1) of the embodiment. Another example is an aluminum alloy member in which solution treatment and aging treatment are performed after plastic processing is carried out on a plate material containing the aluminum alloy of the embodiment. The plastic processing here is performed so that the cross-section of the aluminum alloy member has the aforementioned specific orientation after solution treatment and aging treatment. Yet another example is an aluminum alloy member in which solution treatment and aging treatment are carried out on the aluminum alloy wire (1) of the embodiment. That is, the aluminum alloy member may be linear or rod-shaped. In addition, the aluminum alloy member may be tubular.

[0114] For example, the aluminum alloy member includes an extruded material formed by extruding an aluminum alloy wire (1) with the longitudinal direction of the aluminum alloy wire (1) of the embodiment as the extrusion direction. This aluminum alloy member is extended along the extrusion direction. In this aluminum alloy member, the cross-section to which the orientation degree of the aforementioned 111 planes is measured is obtained by cutting the aluminum alloy member with a plane perpendicular to the extrusion direction. The average value of the orientation degree of the 111 planes obtained by X-ray diffraction over the entire cross-section is 50% or more. In addition, the dispersion of the orientation degree of the 111 planes is 45% or less.

[0115] The aforementioned aluminum alloy member is of high strength because it comprises an aluminum alloy having the aforementioned specific composition and the aforementioned specific structure. Furthermore, this aluminum alloy member is lightweight compared to metal members containing iron-based alloys such as steel. Such an aluminum alloy member can be used in applications where lightweight and high strength are required, such as automotive parts and various structural members.

[0116] (Method for manufacturing aluminum alloy)

[0117] The inventors examined a method for manufacturing an aluminum alloy having excellent strength when solution treatment and aging treatment are performed on an aluminum alloy having the specific composition described above. As a result, the inventors found that it is preferable for the plastic deformation performed immediately before the solution treatment to be cold working and to have a large degree of deformation. Based on this finding, when manufacturing the aluminum alloy of the embodiment, for example, the following method for manufacturing an aluminum alloy may be used.

[0118] A method for manufacturing an aluminum alloy comprises a process for manufacturing a cold-worked material by performing cold working on a material containing an aluminum alloy. The aluminum alloy has a composition in which the aforementioned first element is included within the aforementioned range, and the remainder consists of aluminum and unavoidable impurities.

[0119] The above material is a processed material that has undergone a first plastic processing. The above cold working is a second plastic processing with a degree of processing of 20% or more.

[0120] The above aluminum alloy may have a composition that includes a second element within the aforementioned range in addition to the first element mentioned above.

[0121] Compared to cold working, dislocations are easily released during hot working and warm working. In contrast, since the second plastic working is cold working, the deformation, or dislocations, associated with the second plastic working are more likely to accumulate in the aluminum alloy compared to the case of warm working or hot working. As dislocations accumulate, the 111 planes of the grains are more likely to be oriented during the subsequent solution treatment. As a result, as described above, when solution treatment and aging treatment are performed, a structure in which the 111 planes of the grains are highly oriented across the entire cross-section of the aluminum alloy is obtained.

[0122] The manufacturing method of the aforementioned aluminum alloy is described in detail below.

[0123] <subject matter>

[0124] The material containing the aforementioned aluminum alloy is a cast material that has undergone a first plastic deformation process. The first plastic deformation process is, for example, rolling. The first plastic deformation process is, for example, hot working.

[0125] Early Lotus

[0126] The aforementioned material may be subjected to a softening treatment under the following conditions. Hereinafter, the softening treatment performed on the material may be referred to as an initial softening treatment.

[0127] Conditions for Softening Treatment

[0128] The heating temperature is a temperature selected from a range of 250°C or higher and less than 500°C. The holding time is a time selected from a range of 1 hour or higher and 100 hours or less. The atmosphere during softening is, for example, an air atmosphere or a non-oxidizing atmosphere. Non-oxidizing atmospheres are, for example, a reduced pressure atmosphere, an inert gas atmosphere, a reducing gas atmosphere, etc.

[0129] The heating temperature may be 300°C or higher and 480°C or lower, and furthermore, 300°C or higher and 460°C or lower.

[0130] By performing an initial softening treatment on the material, the plastic workability of the aluminum alloy after the initial softening treatment is enhanced. Consequently, the degree of processing in the second plastic deformation can be significantly increased. If the material is not subjected to an initial softening treatment, dislocations introduced by the first plastic deformation accumulate in the aluminum alloy. As a result, it is easy to obtain an aluminum alloy with a high accumulation of dislocations.

[0131] <Second Plastic Processing>

[0132] The second plastic processing performed on the material is cold working, as previously mentioned. The second plastic processing includes, for example, drawing, rolling, and extrusion. If the second plastic processing is drawing, a wire rod is obtained. If the second plastic processing is rolling, a sheet is typically obtained. If the second plastic processing is extrusion, a wire rod, sheet, pipe, etc., are obtained depending on the shape of the extrusion die.

[0133] Processed drawing

[0134] The greater the degree of processing in the second plastic deformation, the higher the orientation of the 111 planes. From the perspective of improving strength, the degree of processing in the second plastic deformation may be 30% or more, 40% or more, or 60% or more. The degree of processing here is the ratio of the difference between the cross-sectional area before the second plastic deformation and the cross-sectional area after the second plastic deformation to the cross-sectional area before the second plastic deformation.

[0135] <Middle Lotus>

[0136] A softening treatment may be performed during the second plastic deformation process. Hereinafter, the softening treatment performed during the second plastic deformation process may be referred to as an intermediate softening treatment. The conditions for the intermediate softening treatment can be determined by referring to the conditions for the initial softening treatment described above. By performing cold working before and after the intermediate softening treatment, dislocations tend to accumulate more easily in the aluminum alloy compared to cases where warm working or hot working is performed, as described above. Furthermore, by performing the intermediate softening treatment, the degree of cold working after the intermediate softening treatment can be increased. Therefore, dislocations can be accumulated in the aluminum alloy through cold working after the intermediate softening treatment. The greater the degree of cold working after the intermediate softening treatment, the higher the orientation of the 111 planes. Additionally, when performing the intermediate softening treatment, it is desirable that the degree of cold working after the intermediate softening treatment be greater than the degree of cold working before the intermediate softening treatment. In particular, the degree of deformation in cold working after intermediate softening treatment may be 30% or more, 40% or more, or even 60% or more.

[0137] (Method for manufacturing aluminum alloy wire)

[0138] The inventors have found that it is desirable to satisfy the following conditions in order to manufacture the aluminum alloy wire (1) of the embodiment. From this finding, the method for manufacturing the aluminum alloy wire of the embodiment comprises the following first, second, third, and fourth processes.

[0139] <condition>

[0140] Cold drawing is performed. Softening treatment is performed during the drawing process. The degree of processing of the drawing process after the softening treatment is 20% or more and is greater than the degree of processing of the drawing process before the softening treatment.

[0141] The first process is a process for manufacturing a processed material by performing plastic deformation on a cast aluminum alloy that includes the aforementioned first element within the aforementioned range and the remainder being aluminum and unavoidable impurities. The aluminum alloy constituting the cast material may also include a second element within the aforementioned range in addition to the first element.

[0142] The second process is a process for manufacturing a first wired material by performing a first wired processing on the above-mentioned processed material in a cold manner.

[0143] The third process is a process for manufacturing a softened material by performing a softening treatment on the first fresh material.

[0144] The fourth process is a process for manufacturing a second fresh material by performing a second cold fresh processing on the above-mentioned softening material.

[0145] In the method for manufacturing an aluminum alloy wire of the embodiment, the degree of processing in the second drawing process is 20% or more. In addition, the degree of processing in the second drawing process is greater than the degree of processing in the first drawing process.

[0146] The plastic deformation of the first process corresponds to the aforementioned first plastic deformation. The softening treatment of the third process corresponds to the aforementioned intermediate softening treatment. The first drawing process and the second drawing process correspond to the aforementioned second plastic deformation.

[0147] As described above, the method for manufacturing an aluminum alloy wire of the embodiment involves performing cold drawing before and after the softening treatment, which makes it easier for dislocations to accumulate in the aluminum alloy compared to cases where warm or hot working is performed. Additionally, by performing the softening treatment, the degree of processing of the second drawing after the softening treatment can be increased as described above. Therefore, dislocations can be accumulated in the aluminum alloy through the second drawing after the softening treatment. The method for manufacturing an aluminum alloy wire of this embodiment can manufacture the aluminum alloy wire (1) of the embodiment. Furthermore, as described above, a material containing an aluminum alloy having a specific composition has excellent cold drawing performance. The method for manufacturing an aluminum alloy wire of the embodiment using such a material can mass-produce the aluminum alloy wire (1) of the embodiment.

[0148] Each process is described below. Additionally, regarding the basic operations in the method for manufacturing an aluminum alloy wire of the embodiment, a known method for manufacturing an aluminum alloy wire may be referenced.

[0149] Process 1

[0150] In the first process, the casting material is manufactured using, for example, a die casting method, a continuous casting method, etc. In the first process, the plastic processing is, for example, hot rolling, and the processed material is, for example, a continuously cast rolled material. If the processed material is a continuously cast rolled material, a continuous long aluminum alloy wire can be manufactured. In this respect, when the processed material is a continuously cast rolled material, the aluminum alloy wire (1) of the embodiment can be mass-produced.

[0151] The aforementioned initial softening treatment may be performed on the processed material. When the initial softening treatment is performed, the degree of processing in the subsequent first drawing process can be significantly increased, as previously mentioned. If the initial softening treatment is not performed, as previously mentioned, it is easy to obtain an aluminum alloy wire with a large accumulation of dislocations at the end.

[0152] Process 2

[0153] In the second process, it is preferable that the degree of processing of the first drawing process be 30% or more. If the degree of processing of the first drawing process is 30% or more, dislocations introduced by the first drawing process are likely to remain to some extent after the softening treatment. As a result, it is easy to obtain an aluminum alloy wire with a large accumulation of dislocations. The degree of processing of the first drawing process may be 35% or more, or 40% or more. The degree of processing of the first drawing process varies depending on the final wire diameter, but for example, it is selected within the range of 30% or more and 80% or less. The degree of processing of the first drawing process is the ratio of the difference between the cross-sectional area before the first drawing process and the cross-sectional area after the first drawing process to the cross-sectional area before the first drawing process.

[0154] Process 3

[0155] The conditions for the softening treatment in the third process can be determined by referring to the conditions for the initial softening treatment described above. By performing the softening treatment in the third process, the workability of the softened material after the softening treatment is enhanced. Consequently, the degree of processing of the second drawing process in the fourth process can be increased. In particular, the degree of processing of the second drawing process in the fourth process can be made greater than the degree of processing of the first drawing process in the second process. As a result, dislocations can be accumulated in the aluminum alloy through the second drawing process.

[0156] Process 4

[0157] The greater the degree of processing of the second drawing process in the fourth process, the higher the orientation of the 111 planes. If the degree of processing of the second drawing process is 20% or more, it is easy to obtain an aluminum alloy wire with a large accumulation of dislocations in the end. It is also easy to obtain an aluminum alloy wire with a large accumulation of dislocations in the end when the degree of processing of the second drawing process is greater than the degree of processing of the first drawing process. As mentioned above, since it is desirable for the degree of processing of the first drawing process to be 30% or more, the degree of processing of the second drawing process may exceed 30%, 40% or more, and even 60% or more. The degree of processing of the second drawing process is selected within the range of 20% or more and 99.9% or less so that a second drawing material having a predetermined final wire diameter is obtained. The degree of processing of the second drawing process is the ratio of the difference between the cross-sectional area before the second drawing process and the cross-sectional area after the second drawing process to the cross-sectional area before the second drawing process.

[0158] (Method for manufacturing aluminum alloy components)

[0159] The method for manufacturing the aforementioned aluminum alloy member comprises, for example, the following processing and heat treatment processes.

[0160] The processing process is a process for manufacturing a third processed material by performing a third plastic processing on the second plastic processed material or the second wired material described above, on which the second plastic processing described above has been performed.

[0161] The heat treatment process is a process for manufacturing an aged material by sequentially performing solution treatment and aging treatment on the third processed material.

[0162] The third plastic deformation process includes, for example, extrusion, forging, and drawing. The conditions for solution treatment and aging treatment are as described above.

[0163] [Main effects of the embodiment]

[0164] The aluminum alloy of the embodiment and the aluminum alloy wire (1) of the embodiment have high tensile strength when solution treatment and aging treatment are performed. In Test Example 1 below, the above-mentioned effect is specifically explained using the aluminum alloy wire (1) of the embodiment as an example.

[0165] The method for manufacturing an aluminum alloy wire of the embodiment can produce an aluminum alloy wire (1) of the embodiment having high tensile strength in a state where solution treatment and aging treatment are performed.

[0166] [Test Example 1]

[0167] The microstructure was observed and the tensile strength was investigated in the aluminum alloy wire having the composition shown in Table 1 after solution treatment and aging treatment. The manufacturing conditions of the aluminum alloy wire and the results of the investigation are shown in Tables 2 to 4.

[0168]

[0169] (Preparation of samples)

[0170] The aluminum alloy wire of each sample is basically manufactured by cold drawing on continuously cast rolled material. The continuously cast rolled material can be manufactured, for example, by a known Properzi type continuous casting mill. With the exception of some of the samples, softening treatment is performed during the drawing process.

[0171] The first, second, and third compositions in the composition items of Tables 2 to 4 correspond to the first, second, and third compositions shown in Table 1, respectively.

[0172] In Tables 2 to 4, the items for softening treatment indicate the heating temperature (°C) and holding time (hours). For example, “380°C × 10 h” means that the heating temperature is 380°C and the holding time is 10 hours.

[0173] In Tables 2 to 4, samples are described in which conditions are listed in three items: degree of processing (%) of the first drawing process, softening treatment, and degree of processing (%) of the second drawing process. The aluminum alloy wires of these samples are manufactured by performing a cold first drawing process, softening treatment, and a cold second drawing process in sequence on a continuously cast rolled material. The aluminum alloy wires of these samples are not subjected to an initial softening treatment.

[0174] In Tables 2 to 4, a hyphen "-" is indicated in the degree of processing (%) of the first drawing process, and conditions are described in two items: the degree of processing (%) of the softening treatment and the degree of processing (%) of the second drawing process. The aluminum alloy wires of these samples are manufactured by performing a softening treatment on a continuously cast rolled material, followed by performing cold drawing with the degree of processing (%) of the second drawing process. The aluminum alloy wires of these samples are continuously cold drawn after an initial softening treatment is performed on a continuously cast rolled material, and no intermediate softening treatment is performed.

[0175] In Tables 2 to 4, the samples described are those in which conditions are listed in the two items of the degree of processing of the first drawing process (%) and the degree of processing of the second drawing process (%), and a hyphen "-" is listed for the softening treatment. The aluminum alloy wires of these samples are manufactured by performing cold drawing on a continuously cast rolled material with the degree of processing of the first drawing process (%), followed by performing cold drawing with the degree of processing of the second drawing process (%) without performing an intermediate softening treatment. In other words, the aluminum alloy wires of these samples are continuously cold drawn on a continuously cast rolled material, and neither the initial softening treatment nor the intermediate softening treatment is performed. The total degree of processing in this cold drawing is greater than the degree of processing listed in the item of the degree of processing of the second drawing process (%) in Tables 2 to 4.

[0176] The wire diameter of the continuous casting rolled material is selected from a range of 5 mm or more and 30 mm or less. The wire diameter of the second drawn material produced after the second drawing process is a value selected from a range of approximately 1.0 mm or more and 21 mm or less depending on the degree of processing.

[0177] (Tissue observation)

[0178] <Orientation Diagram of 111 Faces>

[0179] A heat-treated wire is manufactured by performing solution treatment and aging treatment on the aluminum alloy wire of each obtained sample under the aforementioned conditions. A disc-shaped sample is obtained by cutting the obtained heat-treated wire in a plane perpendicular to the longitudinal direction of the heat-treated wire. The sample has two circular cross-sections. The entire surface of one of the two cross-sections is smoothed by mechanical polishing. The surface roughness of the cross-section after polishing is approximately 0.2 μm in arithmetic mean roughness Ra. For example, 2000 grit water-resistant paper can be used for mechanical polishing. The entire surface of the polished cross-section is X-ray diffracted as follows.

[0180] As illustrated in FIG. 6, a sample (3) is placed on a surface (51f) including a plane provided on a movable stage (51). This placement is performed so that the aforementioned mechanically polished cross-section (30) in the sample (3) is parallel to the surface (51f), and so that X-rays (6) are irradiated from a predetermined direction (D) with respect to the cross-section (30). The predetermined direction (D) is a direction corresponding to a predetermined plane index (F). The predetermined plane index (F) is a crystal plane specified by a mirror index. Here, the plane index (F) is one of three crystal planes: plane 111, plane 200, and plane 220. Additionally, FIG. 6 shows X-rays (6) from an X-ray source not illustrated and diffracted X-rays (60) as dashed lines.

[0181] By irradiating the cross section (30) of the sample (3) with X-rays (6) from a predetermined direction (D), X-rays (60) diffracted from the cross section (30) are detected by a detector (52). The detection of X-rays (60) is performed repeatedly while moving the sample (3) in two dimensions within a plane parallel to the cross section (30) by a movable stage (51) so that the entire cross section (30) is measured. By doing this, the distribution of diffraction intensity over the entire cross section (30) is obtained. Also, when the sample (3) is moved in two dimensions, the X-rays (6) do not move. Additionally, a calculation device (53) described later is set up to exclude diffraction intensity from a position where the cross section (30) does not exist.

[0182] By changing the angle (θ) and angle (2θ) according to the plane index (F), the distribution of diffraction intensity of 111 planes, the distribution of diffraction intensity of 200 planes, and the distribution of diffraction intensity of 220 planes are obtained. Angle (θ) is the angle formed by the plane index (F) and the X-ray (6). Angle (2θ) is the angle formed by the diffracted X-ray (60) and a predetermined direction (D). Using a theoretical value based on the predetermined direction (D), a value normalized for each of the above-mentioned diffraction intensities is calculated. The above-mentioned normalized value is a value obtained by dividing each diffraction intensity by the theoretical value of the peak intensity of the diffraction intensity of the X-ray diffraction. Using the above-mentioned normalized value, a normalized distribution is calculated from the distribution of each diffraction intensity. That is, the normalized distribution of 111 planes, the normalized distribution of 200 planes, and the normalized distribution of 220 planes are calculated. The above theoretical values ​​can be obtained from the database of the Powder Diffraction File (PDF) released by the International Centre for Diffraction Data (ICDD). Additionally, regarding the peak intensity, instead of the peak intensity of the raw data, the X-ray profile data at each measurement point may be fitted, and the maximum or integral value of the fitting curve may be used. The fitting functions used for the above fitting are, for example, the Lorentz function or the Gauss function.

[0183] For each measurement point, the normalized value of the diffraction intensity of 111 planes, the normalized value of the diffraction intensity of 200 planes, and the normalized value of the diffraction intensity of 220 planes are obtained. In addition, the sum of these three normalized values ​​is obtained. Furthermore, the ratio of the normalized value of the diffraction intensity of 111 planes to the sum is obtained. This ratio is the orientation degree of 111 planes. The average value of the orientation degree of 111 planes is the average of the orientation degrees of 111 planes at all measurement points. The variance of the orientation degree of 111 planes is obtained from the average value above.

[0184] The X-ray (6) can be BL16, for example, located at the synchrotron facility SAGA-LS. The beam line can use X-rays with a wavelength of, for example, λ = 0.0919 nm. The slit width can be, for example, 0.5 mm square. The detector (52) can be, for example, a commercially available two-dimensional detector such as the PILATUS 100K from Dectris. The distance from the cross-section (30) of the sample (3) to the two-dimensional detector is 0.512 m. The computing device (53) can be a commercially available computer.

[0185] The angle (θ, 2θ) is selected according to the aforementioned wavelength. The angle (θ, 2θ) is, for example, the following value when λ is 0.0919 nm.

[0186] When the predetermined plane index (F) is 111 planes, the angle (θ) formed between the 111 planes of the sample (3) and the X-ray (6) is 11.3 degrees. The angle (2θ) formed between the predetermined direction (D) and the diffracted X-ray (60) is 22.6 degrees. Additionally, FIG. 6 shows θ and 2θ as larger than their actual values.

[0187] When the predetermined plane index (F) is 200 planes, the angle (θ) formed between the 200 planes of the sample (3) and the X-ray (6) is 13 degrees. The angle (2θ) formed between the predetermined direction (D) and the diffracted X-ray (60) is 26 degrees.

[0188] When the predetermined plane index (F) is 220 planes, the angle (θ) formed between the 220 planes of the sample (3) and the X-ray (6) is 18.6 degrees. The angle (2θ) formed between the predetermined direction (D) and the diffracted X-ray (60) is 37.2 degrees.

[0189] <tensile strength>

[0190] Tensile strength (MPa) is measured in accordance with JIS Z 2241:2011. Here, tensile strength at room temperature is measured.

[0191] <Component Analysis>

[0192] The composition of the aluminum alloy wire of each obtained sample is the same as the composition in Table 1. That is, the aluminum alloy constituting the aluminum alloy wire of each sample contains the elements shown in Table 1 within the range shown in Table 1, and the remainder consists of Al and unavoidable impurities. Known methods can be used for the analysis of the composition of the aluminum alloy wire. For example, an energy dispersive X-ray analyzer can be used for the analysis of the composition.

[0193]

[0194]

[0195]

[0196] In the following description, samples No. 1 through No. 9, No. 11 through No. 19, and No. 21 through No. 29 are sometimes combined and referred to as the first sample group. Samples No. 101 through No. 104 are sometimes combined and referred to as the second sample group.

[0197] As shown in Tables 2 to 4, the aluminum alloy wires of the first sample group have higher tensile strength compared to the aluminum alloy wires of the second sample group. Quantitatively, the aluminum alloy wires of the first sample group have a tensile strength of more than 425 MPa. Most samples have a tensile strength of 440 MPa or more. Depending on the composition, there are also samples with a high tensile strength of 470 MPa or more.

[0198] One of the reasons for the results obtained as described above is thought to be the difference in the degree of orientation of the 111 planes. In the aluminum alloy wires of the first sample group, the average value of the degree of orientation of the 111 planes is higher and the variance of the degree of orientation of the 111 planes is smaller compared to the aluminum alloy wires of the second sample group. Quantitatively, in the aluminum alloy wires of the first sample group, the average value of the degree of orientation of the 111 planes is 50% or higher, and the variance of the degree of orientation of the 111 planes is 45% or lower. For most samples, the average value of the degree of orientation of the 111 planes is 60% or higher, and the variance of the degree of orientation of the 111 planes is 35% or lower. Depending on the composition, the average value of the degree of orientation of the 111 planes is 70% or higher, and the variance of the degree of orientation of the 111 planes is 30% or lower. This will be visually explained with reference to FIGS. 2 to 5.

[0199] Figures 2 and 3 illustrate the distribution of the orientation of the 111 planes for the aluminum alloy wire of sample No. 3. Figures 4 and 5 illustrate the distribution of the orientation of the 111 planes for the aluminum alloy wire of sample No. 1.

[0200] FIGS. 2 and FIGS. 4 are drawings in which the orientation of the 111 planes at each of the aforementioned measurement points across the entire cross-section of an aluminum alloy wire is converted into shades of grayscale. The shades shown on the right side of FIG. 2 and FIG. 4 represent shades according to the count number. The orientation of the 111 planes at each measurement point is converted to a count number, for example, from zero to 100. Black indicates a count number of zero. White indicates a count number of 100. The greater the orientation of the 111 planes, the larger the count number becomes, that is, the closer it gets to white.

[0201] FIGS. 3 and 5 illustrate the distribution of orientation degrees of plane 111 using contour lines. Each contour line connects measurement points with the same orientation degree of plane 111. FIGS. 3 and 5 illustrate the following four types of contour lines. Thin solid lines are contour lines connecting measurement points with an orientation degree of 20% of plane 111. Thin dashed lines are contour lines connecting measurement points with an orientation degree of 40% of plane 111. Thin dotted lines are contour lines connecting measurement points with an orientation degree of 60% of plane 111. Thick solid lines are contour lines connecting measurement points with an orientation degree of 80% of plane 111.

[0202] In the aluminum alloy wire of Sample No. 3, which has a high tensile strength of 470 MPa, as shown in Fig. 2, there are many white measurement points, a few light gray measurement points, and almost no black measurement points. In other words, there are many measurement points with a large count, and the variation in the count is small. The large number of measurement points with a large count is also supported by the fact that the area enclosed by the thick solid line has a large area, as shown in Fig. 3. Here, the shape and size of the area enclosed by the thick solid line are considerably close to the shape and size of the cross-section of the aluminum alloy wire of Sample No. 3. Furthermore, within this large area, there are almost no areas enclosed by other contour lines. The small variation is also supported by the fact that the areas enclosed by the four types of contour lines mentioned above draw approximately the same shape, as shown in Fig. 3. In this aluminum alloy wire of Sample No. 3, 111 planes are oriented in the direction of the normal of the cross-section equally throughout the entire cross-section. It is believed that the aluminum alloy wire of sample No. 3 has high tensile strength due to having such an oriented 111-plane structure.

[0203] In the aluminum alloy wire of Sample No. 1, which has lower tensile strength than Sample No. 3, dark gray and black measurement points are more frequently observed than in Sample No. 3, as shown in Fig. 4. Additionally, dark gray measurement points are scattered. In other words, it includes measurement points with a small count, and the variation in the count is somewhat large. The inclusion of measurement points with a small count is supported by the presence of multiple areas enclosed by thin solid lines, as shown in Fig. 5. The somewhat large variation is also supported by the fact that the shape and size of the areas enclosed by the four types of contour lines mentioned above are all different, as shown in Fig. 5. Additionally, although there are multiple areas enclosed by thick solid lines, the total area is small. From this, it is believed that the aluminum alloy wire of the second sample group, which has lower tensile strength than Sample No. 1, contains many measurement points with a small count compared to Sample No. 1, and also has a large variation in the count.

[0204] In addition, the following is shown from this test.

[0205] (1) Aluminum alloy wires having the first and second compositions have a larger average value of the orientation of the 111 planes and a smaller dispersion of the orientation of the 111 planes compared to aluminum alloy wires having the third composition. In this respect, aluminum alloy wires having the first and second compositions have higher strength.

[0206] (2) An aluminum alloy wire in which the average value of the orientation degree of the 111 plane is large and the dispersion of the orientation degree of the 111 plane is small in the state in which solution treatment and aging treatment are performed can be manufactured by a manufacturing method that satisfies the aforementioned <conditions>. In the aluminum alloy wire of the first sample group, it is thought that dislocations are accumulated in the state after the second drawing process by satisfying the aforementioned <conditions>. In contrast, in the aluminum alloy wire of the second sample group, the degree of processing of the second drawing process is smaller compared to the aluminum alloy wire of the first sample group. Furthermore, in the aluminum alloy wire of the second sample group, the degree of processing of the second drawing process is smaller than the degree of processing of the first drawing process, or is the same as the degree of processing of the first drawing process. From these points, it is thought that dislocations are not sufficiently accumulated in the aluminum alloy wire of the second sample group in the state after the second drawing process.

[0207] The present disclosure is not limited to these examples, but is defined by the claims, and is intended to include all modifications within the meaning and scope of equivalents to the claims. For example, the composition of the aluminum alloy in Test Example 1 may be changed, or manufacturing conditions such as the degree of processing of the drawing process and the conditions of the softening treatment may be changed. Explanation of the symbols

[0208] 1: Aluminum alloy wire 3: Sample 10: Danbu-myeon 11: Yeonsinbu 30: Cross section 6, 60: X-ray 51: Operating stage 51f: Surface 52: Detector 53: Arithmetic Unit D: Direction F: Surface index θ, 2θ: Angle

Claims

Claim 1 An aluminum alloy having a composition comprising 1.0 mass% or more and 1.3 mass% or less of silicon, 0.5 mass% or more and 1.2 mass% or less of magnesium, 0.3 mass% or more and 0.8 mass% or less of iron, 0.1 mass% or more and 0.4 mass% or less of copper, 0.2 mass% or more and 0.5 mass% or less of manganese, more than 0 mass% and 0.3 mass% or less of chromium, more than 0.001 mass% and 0.1 mass% or less of titanium, more than 0 mass% and 0.2 mass% or less of zirconium, with the remainder being aluminum and unavoidable impurities; wherein, in a state where solution treatment and aging treatment are performed, the average value of the orientation degree of 111 planes obtained by X-ray diffraction of the entire cross-section is 50% or more and the dispersion of the orientation degree of 111 planes is 45% or less, and the tensile strength in a state where solution treatment and aging treatment are performed is 466 MPa or more. Claim 2 A composition comprising silicon at 0.6 mass% or more and 1.5 mass% or less, magnesium at 0.7 mass% or more and 1.3 mass% or less, iron at 0.02 mass% or more and 0.4 mass% or less, copper at 0.5 mass% or more and 1.2 mass% or less, manganese at 0.5 mass% or more and 1.1 mass% or less, chromium at more than 0 mass% and 0.3 mass% or less, zinc at 0.005 mass% or more and 0.5 mass% or less, titanium at 0.01 mass% or more and 0.2 mass% or less, zirconium at 0.05 mass% or more and 0.2 mass% or less, with the remainder being aluminum and unavoidable impurities; wherein, in a state where solution treatment and aging treatment have been performed, the average value of the orientation degree of the 111 planes obtained by X-ray diffraction over the entire cross-section is 50% or more, and the dispersion of the orientation degree of the 111 planes is 45% or less, and the solution treatment and aging Aluminum alloy having a tensile strength of 487 MPa or more in a treated state. Claim 3 A composition comprising 0.9 mass% or more and 1.3 mass% or less of silicon, 0.8 mass% or more and 1.2 mass% or less of magnesium, greater than 0 mass% and less than or equal to 0.4 mass% of iron, greater than 0.65 mass% and less than or equal to 1.1 mass% of copper, greater than 0.55 mass% and less than or equal to 1.15 mass% of manganese, greater than 0 mass% and less than or equal to 0.35 mass% of chromium, greater than 0 mass% and less than or equal to 0.25 mass% of zinc, greater than 0 mass% and less than or equal to 0.075 mass% of titanium, and greater than 0.05 mass% and less than or equal to 0.17 mass% of zirconium, wherein the remainder is aluminum and unavoidable impurities, wherein, in a state in which solution treatment and aging treatment are performed, the average value of the orientation degree of 111 planes obtained by X-ray diffraction over the entire cross-section is 50% or more, and the dispersion of the orientation degree of said 111 planes is 45% or less, and the solution treatment and Aluminum alloy having a tensile strength of 447 MPa or higher in an aged state. Claim 4 An aluminum alloy wire made of an aluminum alloy as described in any one of paragraphs 1 to 3. Claim 5 delete Claim 6 delete Claim 7 delete Claim 8 delete

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