JPS6024217A - Manufacture of aluminum wire rod - Google Patents

Abstract

PURPOSE:To prevent the breaking of a wire rod during drawing and to improve the workability in bending of the drawn wire rod by drawing a rough drawn wire rod consisting of various kinds of Al wire rods especially high tensile Al alloy by using a roll die having a diameter not less than the specific times the diameter of the wire rod. CONSTITUTION:In a method for drawing a rough drawn wire rod consisting of Al, Al alloy, or high tensile Al alloy, the drawing is performed by using a roll die having a diameter of >=5 times the diam. of a wire rod to be drawn. In this case, the diameter of roll die means the inner diameter of groove, and a pair or more of roll dies are used for drawing. Further, in case of drawing a rough drawn wire rod consisting of high tensile Al alloy of >=15kg/mm.<2> tensile strength, its tensile strength is elevated to >=23kg/mm.<2>. In this way, the breaking of wire rod during drawing is prevented, and the workability in bending of the obtained wire rod is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing aluminum wire rods used for electric wires, etc., and in particular, to prevent wire breakage during expansion and contraction processing and to improve bending workability of the obtained wire rods.

Conventionally, aluminum wire rods have been manufactured by drawing aluminum, aluminum alloys, or high-strength aluminum alloys using ordinary drawing dies from rough drawn wires made by stretching, extrusion, or continuous VI forming and rolling methods. It is used for various purposes including electric wires. In recent years, as the demand for electricity has increased, overhead power transmission lines have shown a tendency to increase in capacity.At the same time, it has become difficult to secure land for towers and power transmission routes, and power transmission routes have moved to mountainous areas and the number of long-span power transmission sections has increased. There is.

In addition, power plants are being built on remote islands due to environmental concerns, and the number of long-span power transmission sections, such as across straits, is increasing.

High-strength conductive aluminum alloys have conventionally been used in such long-span power transmission sections, but aluminum wires generally tend to have poor bendability as their strength increases. On the other hand, in applications where the wire is subject to bending deformation, such as overhead power line work, the bendability of the wire is an important characteristic.

As with wire rods made of ordinary conductive aluminum (IE CΔ()), even wire rods with relatively low strength tend to have poor bending properties as they become more susceptible to cold wire drawing. It is known that as the strength increases, the bending workability deteriorates.In particular, high-strength aluminum alloys (Δ(- to 4a-st) called No.
When the wire is expanded and contracted using a die during normal drawing, a crack called an arrow-shaped cupping occurs in the center of the drawn wire, and wire breakage is likely to occur.

In view of this, the present invention is based on the results of various studies regarding the wire drawing pressurization of various aluminum wire rods, especially high-strength aluminum alloy wires.
By drawing the wire using a roller die, wire breakage during the stretching process can be reduced, and the resulting wire can be bent easily.
The present invention has developed a method for producing an aluminum wire rod according to the present invention based on the findings that it is possible to improve the first two L- The wire drawing process is performed using a roller die having a diameter of five times or more the diameter of the wire rod.

That is, the present invention is for drawing a rough drawn wire produced by a conventional method through one or more sets of roller dies having a diameter of five times or more the diameter of the wire to be processed. In the invention, aluminum refers to ordinary electrical aluminum and various types of pure aluminum, and aluminum alloys are referred to as A, f'! -7r series heat-resistant aluminum alloy and various aluminum alloys, and high-strength aluminum alloys include 5005 alloy, No.
M(1-C1l-"e alloy, AJ!-Zr-Fe-C
High-strength aluminum alloys for conductivity such as U alloy, and even 201
These are high-strength aluminum alloys for drawing such as 7 alloy, 2024 alloy, 5052 alloy, and 5056 alloy.

The present invention is for drawing the rough drawn wires of the above-mentioned various aluminum, aluminum alloys, or high-strength aluminum alloys through a roller die having a diameter of five times or more the wire diameter of the wire to be processed. It prevents wire breakage due to cupping during wire processing and improves the bending workability of the obtained wire, especially the strength of 1η1! iKD/
From this high-strength aluminum alloy, add a rough wire of /7 to the middle line]', and then add a strong 1σ23K<1/#III+
2 or more) Prevents cupping breakage when using aluminum wire material
This method has notable effects such as improving the bending properties v1 of the obtained wire.

In the present invention, the roller die is a known one consisting of a pair of grooved rolls placed above and below or on the right, and for wire drawing, a known one-head wire drawing machine or a continuous It is more efficient and economical to use a wire drawing machine, especially a continuous wire drawing machine.The diameter of the roller die is the diameter of the inner diameter of the groove, and the diameter of the roller die is the diameter of the wire being drawn. The reason why the diameter is set to be 5 times or more is because if it is less than 5 times, cupping breakage tends to occur and bending workability cannot be obtained.
It is most effective at a magnification of ~20 times, and the effect reaches saturation even when the magnification is increased to 20 times or more. Therefore, the upper limit of the roller die is not particularly limited, but is practically limited by the scales of the wire drawing machine or the space in which the roller die is placed.

5- Also, surface reduction polishing using one roller die is not particularly limited, but from the viewpoint of wire breakage and bending workability,
It is desirable that the wire width be within the range of 0 to 50%, and although the effect is recognized when it is less than 10%, it is uneconomical because the number of wire drawings (the number of passes in a continuous wire drawing machine) increases to process the wire to the desired wire diameter. If it exceeds 50%, the tension required for drawing increases, making wire breakage more likely. Since the diameter of the wire rod is reduced by the wire drawing process, the diameter of the roller die should be at least 5 times the wire diameter of the wire rod to be drawn. Therefore, the diameter of the roller die assigned to each pass may be different. Although the wire is drawn through one or more sets of roller dies, in order to particularly improve dimensional accuracy, it is preferable to perform the final wire drawing using a normal drawing die.

The mechanism by which the present invention improves the bending workability of aluminum wire is not clear, but unlike conventional drawing dies, work hardening is different between the center and the outer periphery, resulting in uneven strength in the cross section. On the other hand, when processed through a roller die, the work hardening of the center and outer periphery of the wire becomes uniform, and the strength and residual stress in the cross section become uniform, thereby preventing the occurrence of internal microvoids, cracks, etc. It is presumed that this is because of this. :1: Prevents the occurrence of binding cupping and reduces wire breakage.
It is considered that 0.

The present invention will be explained in detail below using Examples.

Table 1 shows d'h aluminum alloy for TI conductivity (50
05 alloy, No. I aluminum, Af! , -M(1-Cu
-Fe alloy), A, e-7r conductive aluminum alloy, conductive aluminum (ECAf), and high strength aluminum alloy for wrought use (50! i2 alloy, 5056 alloy, 20
17 alloy), a rough wire was made by continuous &8 rolling, and this was continuously expanded and contracted using the strip '1 shown in Table 2 to produce an aluminum wire rod.

In addition to investigating the number of wire breaks during expansion/contraction processing,
A tensile test and a bending test were conducted on the obtained wire rod.

The binding is also listed in Table 2.

Regarding No. 1 aluminum, the rough drawn wire was solution treated at 530℃ for 2 hours, cooled in water, aged at room temperature for 1 week, then wire drawn, and after wire drawing, tempered at 150℃ for 6 hours. Ta. Also, for 2017 alloy, set the rough line to 5
After solution treatment at 00℃ for 2 hours, cooling with water, and stretching, 17
Tempering treatment was performed at 0°C for 6 hours. Furthermore, electrical aluminum ingots with a purity of 99.8% were used to melt the alloys shown in Table 1.

The number of wire breakages was calculated by calculating the number of wire breakages by 10 tons before wire drawing, and expressed as the number of wire breakages per ton. In addition, in the bending test, a radius twice the diameter of the wire is held between the right metal fittings, and the bending angle is repeated 90° left and right until it breaks.
Counted the number of bends.

Table 1 Alloy Name Symbol Composition (wt Negative Fe Si Ivlo Cu Mn CrECA A
O,120,06---AJ! -Mo -Cu -
Fe B O, 250,060,120,14-- No. I aluminum CO, 200,580,630,01-
-5005[) 0,160.080.82-- -5
052 E O,250,102,500,050,0
10,205056FO,200,105,100,
050,110,122017G O,520,480
,604,100,72-A,e-Zr(1) H0,
120,05---〃(2) I 00120.05
− -- −〃(3) J O,450,06-0,0
8--; ) Zr Af -Remaining 0.04511 0.12 O, Oa.

Table 2 (1) Method of the present invention IA 5.5 4 45 11.3〃2B
7,0 4 30 76.6 〃3C8,062684,0 〃4D 10,0 6 20 74.5〃5E 15,
0 5 35 88,7〃6F 15.0 6 30
88,7〃7G 20,0 7 30 91.9118
H8,0101580,5 #91 7,5 6 22 77.6 II 10 J 10.0 6 25 82.3 Comparative method 11A 3.0 4 45 91.3,. 12C4,
062684,0 #'13E 3,5 5 35 88,7//14G
4.5 7 30 91.9n 15 1 3.0 6
22 77.6,. 16J 3.5 6 25 82
．． 310- Final wire tensile strength bending properties Number of wire breaks diameter (s)
(K(] /lrmr') (number of times) (times/lo
n) 2.8 19.2 10 0 4.6 24.5 10 0 3.8 33.2 8 0 4.8 25.0 9 0 3.2 31.5 9 0 3.2 44.2 8 0 2.7 5g, 6 6 0 4.2 18.0 10 0 4.5 17,6 10 0 4.0 25.0 9 0 2.8 19,0 6 0 3.8 32.5 5 0 3. 2 31,0 6 1 2.7 57.8 4 3 4.5 17.7 6 0 4.0 24.8 6 0 Table 2 (2) Conventional method 17 B (Drawing die) 6 21 76
．． 6/l 18C(n) 6 26 76.677
19F (/l) 6 20 74.5/J 20H
(n) 6 22 77.6#21J (n) 6
25 82.311- End wire Tensile strength Bending properties Number of wire breaks ￥ (#)
(Kg/#2) (Number of times) (Times/lon) 4.6
24.0 6 0.1 3.8 32.6 4 0.2 4.8 43,5 4 6 4.5 17.8 6 0 4.0 24.7 5 0.1 Various aluminum shown in Table 1 , aluminum alloys and high-strength aluminum alloys (No, A to J) are wire-drawn using a [1-lar die]. Compared to the conventional method of wire drawing using a die, it can be seen that the bending properties are significantly improved and wire breakage during wire drawing is reliably prevented.

On the other hand, in the comparative method in which the diameter of the roller die specified in the method of the present invention is less than five times the diameter of the wire rod to be wire-drawn,
In either case, wire breakage during wire drawing can be prevented to some extent, but almost no improvement in bending properties is observed. In particular, in the production of high-strength aluminum alloy wire rods, not only is no improvement in bending properties observed, but it is also found that wire breakage during wire drawing cannot be almost prevented.

As described above, according to the present invention, wire breakage during wire drawing can be effectively prevented, and the bending workability of the obtained wire rod can be significantly improved. In particular, the yield of high-strength aluminum alloy wire rods can be improved, Used for long-diameter power transmission lines that undergo bending deformation,
This has a remarkable effect.

Claims (3)

[Claims] (1) In the method of drawing rough drawn wire from aluminum, aluminum alloy or high-strength aluminum alloy, a roller die having a diameter of 5 times or more the diameter of a JII T-1?1 wire is used. A method for manufacturing aluminum wire rods, which is characterized in that the aluminum wire rods are drawn by (2) The method for manufacturing an aluminum wire according to claim 1, wherein the aluminum wire is expanded and contracted through one or more sets of roller dies. (3) High-strength aluminum alloy rough drawn wire with a strength of IF+K(]/m2 or higher is wire-drawn to a strength of 23K LJ/a after 1 stroke.
2. The method for producing an aluminum wire according to claim 1 or 2, wherein the aluminum wire rod has a diameter of 2 m 2 or more.