JPS6029456A - Production of conductor consisting of high-strength heat-resistant aluminum alloy - Google Patents

Abstract

PURPOSE:To produce an Al alloy wire for power transmission having excellent strength and flexibility without decreasing conductivity and heat resistance by adding a small amt. of Fe to an Al-Zr alloy having excellent resistance to heat and subjecting the alloy to hot rolling and heat treatment under specific conditions then to cold drawing. CONSTITUTION:The melt of an Al alloy contg. 0.1-0.8% Zr, 0.07-0.8% Fe, 0.05-0.8% Si, 0.005-0.5% Cu and 0.005-0.5% Ni is continuously or semi- continuously cast at >=740 deg.C. The billet is immediately hot-rolled without heating the same to produce a roughly drawn wire. The roughly drawn wire is heated for 0.5-2.00hr at 200-500 deg.C to improve strength, etc. owing to precipitation of Zr and thereafter the wire is cold drawn to a wire rod. The Al alloy wire having excellent strength, heat resistance and flexibility as a steel cored Al alloy twisted wire to be used for a power transmission wire is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a high-strength, heat-resistant aluminum alloy conductor, and in particular, has conductivity and strength equivalent to that of conventional high-strength, heat-resistant aluminum alloy conductors; Furthermore, it is possible to produce a conductor having far superior heat resistance and flexibility.

Traditionally, overhead power transmission lines have been made of copper-core aluminum stranded wire (AC3R) using conductors made of electrical grade Δ, e (ECA wire), and special transmission wires (AJ2-Zr with heat resistance added at the end of q) have been used. Twisted heat-resistant aluminum core stranded wire (TAC5R) using a conductor made of a high-strength aluminum alloy, such as TAC5R, has been used for long-span power transmission lines.
A copper core high potassium aluminum alloy stranded wire using a conductor made of a 05 series alloy (Δsoft - 0.5 to 1.hvt% Mg) was used.

Heat-resistant A-7R alloys cannot be used as conductors for long-span power transmission lines, because the strength of the conductor does not become very high regardless of the Zr content, and all aluminum alloy stranded wires ( It could not be used as a conductor for AAAC).

In addition, 5005 series alloy (j,
The tensile strength is excellent at 24Kg/mm2, but the heat resistance [
J.ECA! However, it had the disadvantage of poor heat resistance.

BACKGROUND ART In recent years, as the demand for electric power has increased, there has been a demand for conductors that are heat resistant and strong from the standpoint of large-capacity power transmission. To deal with this, the heat resistance of 5005 series alloys has been improved, and AJ! -Z For r-based alloys, improvement of strength has been studied.1. Fe in l'1-Zr alloy
A high-strength, heat-resistant aluminum alloy has been proposed that has improved strength without significantly deteriorating conductivity and heat resistance by adding .

This alloy has a conductivity of 56% lAC3 and a tensile strength of 25 Ku/
Although it has excellent properties with a heat resistance of 93% (heated at 230°C for 1 hour), it has the disadvantage of poor flexibility, which is important for overhead power transmission, and further improvement in heat resistance is desired. There is.

In view of this, as a result of weighing and inspection, the present invention has been developed to have high-horn conductivity and strength equivalent to conventional high-strength, heat-resistant aluminum alloy conductors, but with far greater thermal flexibility. & 4 A method for producing heat-generating aluminum alloy was developed.
(abbreviation), FeO, 07-0.8%, 810.05
~0.8%, CuO,005~0.5%, Ni0
A molten aluminum alloy containing -005 to 0.5% and the remainder (and normal impurities) is continuously or semi-continuously cast at a temperature of 740°C or higher, and the resulting ingot is immediately heated without reheating. Roll it to make a rough wire, which is 100 to 50
Item b is characterized in that the wire is heated at a temperature of 0°C for 0.5 to 200 [1' yen] and then cold wire drawn.

That is, in the present invention, by casting a molten alloy having the above-mentioned composition range at a temperature of 740° C. or higher, Zr contained therein is sufficiently dissolved in solid solution. This was immediately hot-rolled into a rough wire without reheating, and then heat-treated to precipitate Zr, thereby improving heat resistance and recovering electrical conductivity due to the precipitation of Zr. Strength is improved by precipitation hardening. The strength was further improved by cold wire drawing. This J is made of sea urchin and has the same electrical conductivity and strength as conventional high-strength heat-resistant aluminum alloy conductors, but also exhibits far superior heat resistance and flexibility. This conductor is made of S body and can carry more current than C. Also, this conductor is an all-aluminum stranded wire conductor without the core loss found in ordinary copper-core aluminum stranded wire, making it possible to use C. It is something that has been trained.

However, the reason why the alloy composition is limited as described above in the present invention is as follows.

7r was added to improve heat resistance,
This is because if the 7r content is less than 0.1%, the effect of improving heat resistance is small, and if it exceeds 0.8%, the decrease in electrical conductivity becomes more significant than the effect of improving heat resistance, making it impossible to use it as a conductor. Fe is added to improve strength, but if its content is less than 0.07%, the desired strength will be reduced to 1.
This is because as the amount exceeds 0.8%, the conductivity decreases more rapidly and it becomes impossible to use it as a conductor.

81 is added to promote the precipitation of Zr, but if its content is less than 0.05%, the effect of promoting Zr precipitation is small, and if it exceeds 0.8%, the effect of promoting Zr precipitation is This is because the conductivity of the conductor is lower than that of the conductor, and it becomes unusable as a conductor.CLI is added to improve the flexibility of the conductor, but its content is less than 0.005%. , the effect of improving flexibility is small,
This is because if it exceeds 0.5%, the conductivity will drop significantly and it will no longer be possible to use it as a conductor. In addition, Ni is added to increase the strength of △(71 to
．． This is because if it exceeds 5%, the conductivity will drop significantly and it will no longer be possible to use it as a conductor.

Incidentally, the impurity is common electrical grade A (as long as it is contained in the base metal, it will not impair the characteristics of the conductor.

The reason for continuous or semi-continuous casting of a molten alloy having such a composition range at a temperature of 7110°C or higher is to ensure that Zr is sufficiently dissolved in solid solution during VF production, and the casting hot stone of the molten metal is cast at a temperature of 740°C or higher.
This is because if it is less than 4f, the solid solution amount of 7r will be less than 4f, and sufficient heat resistance will not be obtained no matter how the subsequent hot rolling and rough wire heat treatment conditions are selected. In addition, heating the hot-rolled rough drawn wire at a temperature of 100 to 500°C for 0.5 to 200 hours imparts heat resistance (=J) due to the precipitation of Zr.
This is to restore electrical conductivity and improve strength through precipitation hardening. At temperatures below 100°C, a sufficient precipitation effect cannot be obtained, and at temperatures above 500°C, the strength decreases significantly and the processing time increases. This is because when the time is less than 0.5 hours, the recovery of the conductivity is small, and when the time exceeds 200 hours, the strength decreases greatly. After precipitating Zr in this way,
The reason why this material is subjected to cold wire drawing is to further increase its strength through work hardening, and through this processing, the strength is equivalent to that of conventional high-strength aluminum alloys.

The present invention will be described in detail below with reference to examples.

Electrical A with a purity of 99.6% (base metal, △(-5%7r,
ΔSoft-6%Fe, Af-50%CLI, ΔSoft-20%S
;, Al and 10% Ni were blended and melted to the composition shown in Table 1, and the molten metal was prepared as shown in Table 1. l
The ingot was poured into a belt-and-wheel continuous casting and rolling mill at a temperature of 2000 m2, and an ingot with a cross-sectional area of 2000 R, m2 was continuously cast. .5 I drew the rough line for nun. After heat-treating this rough drawn wire at the humidity shown in Table 1, it was cold-drawn to a diameter of 4.
7j manufactures nwn conductors.

The gJ conductivity, tensile strength, heat resistance, and flexibility of the conductor thus manufactured were measured. The results were obtained by continuously casting and rolling a conventional high-strength, heat-resistant aluminum alloy molten metal using a belt-and-wheel type continuous casting and rolling machine.
A comparison is made in Table 1 with the characteristics of a conductor that was cold drawn after being made into a roughly drawn wire of g.

The electrical conductivity was calculated by measuring the electrical resistance using a Kulbin double bridge, the tensile strength was measured using an Amsler type tester, and the heat resistance was calculated by heating the sample to 230°C for 1 hour. It is expressed as the ratio of the tensile strength after heating to the tensile strength. Flexibility was measured by holding the sample between curved surfaces twice the diameter and repeatedly bending the sample at 90° alternately to the right and to the right to measure the number of times the sample was bent at 90° until it broke.

Table 1 H) 4 manufacturing method NO alloy composition (%) Casting wet IZ
r Fe Si Cu Ni AJI! ('C) Method of the present invention 1 0,2 0.6 0.1 0.01 0,0
1 740 left! I2〃0.40.150.30.3I
Noah 80〃3ノ, 0.10,20,10,4J/noll
14 n O, 20, 150, 40, i n' nI!
5 0.4 0,6 0,1 0.01 0.01,
, IIIj(') IIO,40,150,3Q,3
n n〃 7 ll 0.1 0.2 0.1 0.
4 〃 II8 lO120,40,40,1+, ,
11!9 0.6 0. G Oll 0.01 0,0
1 +, 800n 10 jJ O040,150,
30,3n II11 〃0.1 0.2 0.1 0
．． 4.

112, + 0.2 0.6 0,4 0.1 +,
I.

Comparative method 13 0.05 h O,20,1ll! 78
0! ! 14 0.95 〃n II n 15 0.4 0.04 〃〃 IT 16 H1,OJJ JJ!ノ1711O,20,03〃 1118II〃0.901I u19horn〃0.20,001〃nu JJ 20 n n n Q, 7 〃21〃II〃0,050.0O11II! JT 22
Jr IT II JJ Q, 7 II IIJ/2
3IIノJIINO, 1n700II24II7/II
NoInI Noah 80n 25 n II 11 II n 26 IT Jr II JJ /7 27 II JJ 11 /7 (1) 1 Heat treatment Electrical conductivity Tensile strength Heat resistance flexibility (℃) X
(hr) (%IAC8) (K(1/mm2) (
%) (times) 200x 184 55.7 25.8
97.5 29200x 48 56.2 24.8
97.0 30350x 12 56,8 25,6
96,2 26350X 24 55,8 24,1
95.2 30400x 96 55.9 25,0
97. [i 26400x 48, 56.0 25
．． 2 98.0 30350x 2/l 55.8 2
4.1 98.0 32400x 24 56.3 2
4.6 98.6 30500x 48 56,6 2
6,3 99,2 26500x 24 55.9 2
5J 99.6 28500x 1 55, 3 24,
6 99.9 2B200x 184 57.6 24
．． 8 97.2 31350x 24 56,3 24
,7 76.3 2[)lIX I49,2 25,1
99.6 29nX u 56,2 1Ci, 2 7
4,3 30IIX n50,1 24.6 97,6
27/IX u 52,3 17,2 96,6 3
1〃x, n 49,6 25.6 97j 28n×
n 56,6 25.0 97. (i 14II×)1
50.62ノL891'1.129n×// 5G, 9
18,6 96.8 30 x 1149.4 25
,4 97.2 27/IX u 55.9 25.1
78.2 3080x 〃50.2 18,8 98
．． 3 31560x jJ 55.8 16,6 97
．． 6 30350x O,151,225,397,8
26//X 230 5B, 3 15,6 97.1
28 Manufacturing method No. Alloy, Silk 7r F
e Si Cu Ni Conventional 28 0,1 0.7 0.1 - -7!2
9 〃0.35,, 0.2 -1130 IO,4
On 0.15 - Table 1 (2) 6) Casting) Buddhist method 11 degree heat treatment Electrical conductivity Tensile strength Heat resistance Flexibility AJ! (℃) (℃) X (hr) (%
I AC8) , <Kq/mm2) (%) (mark remaining
730 - - 56.0 25.0 94.3 1G
--55,625,692,120 --56,125,293,618 J that is clear from Table 1: Sea urchin invention method No. 1 to 1
The conductor manufactured according to 2 has a conductivity of 55.3 to 57.6%.
IΔC8, tensile strength 24.1-26.3K g, /recommendation 2, heat resistance (230℃ x 1 hour) 95.2-99.9
%, flexibility of 26 to 32 times, conventional method NO,
It can be seen that compared with No. 28 to No. 30, the conductivity and tensile strength are almost the same, and the heat resistance and flexibility are far superior.

On the other hand, comparative method No.
, 13 to 27 are found to be inferior in any one of electrical conductivity, tensile strength, heat resistance, and flexibility. That is, Comparative Method No. 13, which contains less 7r, and Comparative Method No. 23, which has a lower casting temperature, both have poor heat resistance, while Comparative Method No., + which contains a large amount of 7r.
4. Comparative method No. 1 with the highest Fe content, 1B, Comparative method No. 1 with the highest S1 content, IB, Comparative method No. with the highest CuS content
, 20. Comparative method No. 26 with a high Ni content and Comparative method No. 26 with a short heat treatment time had a significant decrease in conductivity, while comparative method No. 15 with a low Fe content had poor tensile strength and heat resistance. is inferior. Furthermore, Comparative Method No. 17 with a low S content and Comparative Method No. 24 with a high heat treatment temperature were both inferior in conductivity and tensile strength, and Comparative Method No. 19 with a low Cu content. In ``Comparative method No. 21, which does not improve the tensile strength and has a lower Ni content, Comparative method No. 25, which has a higher heat treatment temperature, and Comparative method No. 27, which has a longer heat treatment time, the tensile strength is lower. It turns out that the quality is inferior.

As described above, the present invention provides a high-strength heat-resistant aluminum alloy 7 that has conductivity and strength almost equivalent to conventional high heat-resistant aluminum alloy conductors, and has far superior heat resistance and flexibility. It can be used for steel-core high-strength heat-resistant aluminum alloy stranded wires and all-aluminum alloy stranded wires, and has a significant effect on increasing power transmission capacity.

Procedural amendment teeth (voluntary) July 17, 1980 1. Indication of the case 1988 Patent Application No. 139218 2. Name of the invention Method for manufacturing high-strength heat-resistant aluminum alloy conductor 3. Person making the amendment Relationship with the case Patent applicant address: 2-6-1 Marunouchi, Mibuyota-ku, Tokyo Name:
(529) Furukawa Electric Co., Ltd. 4, Agent address: 16 Kanda Kita Jorimono-cho, Chiyoda-ku, Tokyo 101
English Building 3rd Floor 6 Contents of amendment (1) The scope of claims is amended as shown in the attached sheet.

(2) In the detailed description of the invention, the words "100-500°C" on page 4, line 3 and page 5, line 16 are corrected to "200-500°Cj."

(3) On page 5, line 20, the phrase “less than 100℃” has been replaced with “
"Less than 200 degrees Celsius".

Claims Zr O, 1 to 0.8 wt%, Fe O, 07 to 0.8
wt%, 3i 0.05-0.8wt%, CLI O
,,005~0.5wt%,Nio,005~0.5
% wt% and the remainder (and normal impurities) is continuously or semi-continuously cast at a temperature of 740°C or higher, and the resulting ingot is immediately hot-rolled without reheating. Arahiki line Toshi, cholera 200・” 500℃
The manufacturing process of a high-strength heat-resistant aluminum alloy conductor is characterized in that the conductor is heat-treated for 5 to 200 hours at a temperature of '0.

Claims (1)

[Claims] Z r O, 1 to 0.8 wt%, F e O, 07 to 0
．． 8wt%, SiO, 05-0.8wt%,
CuO,005~0.5wt%, NiO,0
A molten aluminum alloy containing 05 to 0.5 wt% and the remainder A (and normal impurities) is continuously or semi-continuously boiled at a temperature of 740°C or higher to obtain 1. It is hot rolled to make a rough wire, which is 100~
After heat treatment at a temperature of 500°C for 0.5 to 200 hours,
Ii is a high-strength, heat-resistant aluminum alloy conductor that is characterized by cold wire drawing. IL construction method.