JPS59110769A - Preparation of conductive heat resistance aluminum alloy wire - Google Patents

Abstract

PURPOSE:To obtain a conductive heat resistant Al-alloy wire keeping good conductivity and having high resistance, by a method wherein an Al-Zn-Fe-Si type alloy having a specific composition is cast under a specific temp. condition and the cast alloy is subjected to heat treatment after hot processing and cold wire drawing. CONSTITUTION:An Al-Zr-Fe-Si alloy consisting of, on a wt. basis, 0.05-0.10% Zr, 0.07-0.40% Fe, 0.03-0.10% Si and the remainder of Al and satisfying a formula 40Zr%<=5.9-9Fe%-5Si% is prepared by melting. This alloy is cast at a casting temp. of 680 deg.C or more and the obtained cast ingot is subjected to hot processing in an area reduction ratio of 90% or more while cooled to 270 deg.C or less to form a roughly drawn wire. This wire is succeedingly subjected to cold wire drawing in an area reduction ratio of 70% or more and the obtained wire material is subjected to heat treatment at 200-600 deg.C. By this method, an Al- alloy wire having good tensile strength and heat resistant characteristics and excellent conductivity is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a heat-resistant aluminum alloy wire for conductive use, and more specifically, a novel heat-resistant aluminum alloy wire for conductive use that has a high conductivity of 58%lAC3 or more and can significantly improve heat resistance characteristics. The present invention relates to a manufacturing method.

Conventionally, AA-Zr has been used as a heat-resistant aluminum alloy for conductivity.
Heat-resistant aluminum having a conductivity on the order of 58% lAC3 is known.

This heat-resistant aluminum is JEC-197 (197'
According to the standard 6), for example, a wire diameter of 4.8 tMlφ, electrical conductivity of 58 cm or more, AC8 or more, tensile strength of 162 V/song or more,
Heat resistance (remaining tensile strength after heating at 270°C for 1 hour)
It has properties of 90% or more and is widely used as a conductor for overhead power transmission lines. However, in the field of overhead power transmission lines, with the recent increase in power transmission capacity, there is a strong desire for improved heat resistance to cope with the increase in power transmission capacity with the same wire diameter.

However, it is extremely difficult to improve heat resistance while ensuring tensile strength and electrical conductivity.

In view of the above points, the present inventors conducted intensive research to improve the characteristics of heat-resistant aluminum for conductive use, and found that Zr
0.05~0. l Owt%, FeO, 07~0.4
0 wt, %, Si 0.03~O,J Owt% and 0, balance A, t\, and the 441 composition range of Zr, 11:d"e and 0, Sl.Formula: 40 Zr (
wt%) < 5.9-9 Fe (wt%) -58
AL-Zr-Fe − that satisfies i (wL’ly )
The Si-based alloy is melted and cast at a casting temperature of 680'C or higher, and the resulting ingot is cooled to a material temperature of 2.
A rough drawing wire is formed by hot drawing with an area reduction of 90% or more until the temperature reaches 70°C or more, and then the core drawing wire is cold drawn with an area reduction of 70% or more. Then, we get F and the line A is 2
By heat treatment at a temperature of 00°C to 600°C,
The present application has been completed by obtaining a conductive heat-resistant aluminum alloy wire that has particularly high heat resistance while maintaining good conductivity.

In the present invention, the composition range of each additive element of the At-Zr-F"e-8i alloy used is required to be within the range 1-1. If the composition range is outside the above range, the desired properties may not be obtained. zr or a, 05 wtLt H
In the case of 0.0, the target heat resistance characteristics cannot be obtained. L O
At t exceeding wt≠, the conductivity decreases significantly. If the amount of Fe is less than 0.07 wt%, appropriate strength cannot be obtained;
If the amount exceeds 40 W, high conductivity can be expected.

Further, if the S1 content is less than 0.03 wt%, good strength cannot be obtained due to the synergistic effect with the Fe element, and if it exceeds 0.10 wt≠, the electrical conductivity is significantly reduced. In addition, A in the present invention
In the t-Zr-Fe-Si alloy, Zr and F
It is necessary that the amounts of e and Si added are within the composition range indicated by -F and at the same time satisfy the following formula (A).

40Zr (wt%)≦5. ! Q-9P″e(wt%
)-5Si (wt%)... (A) ZrS If Fe and S] do not satisfy the above formula, an alloy with high conductivity and high heat resistance cannot be obtained under the manufacturing conditions described below. . .

In the present invention, the At-Zr-F'e-Si alloy is melted and cast at a temperature of 680°C or higher, and the resulting ingot is cooled to a casting temperature of 270°C or lower. Continuous casting and rolling with hot working of 90% or higher surface area is performed for 8 rounds until the temperature is reached to form a rough drawing line. The above casting temperature is 6
The reason why the temperature is set at 80°C or higher is that coarse floating crystals are formed when the casting temperature is lower than 680°C.
This is because the distribution of carbon fibers becomes uneven, resulting in a decrease in heat resistance and strength. In this sense, the casting temperature is 700°C or higher1:
"ga": preferred. In addition, the rolling conditions are to increase the strength of the rough wire as much as possible, for example, in the case of a rough wire diameter of 95 mm, to a high strength of 13 K97 mm2J, and to achieve the desired excellence in relation to the subsequent cold wire drawing and heat treatment - II Pr. In order to obtain heat resistance properties, the rolling end temperature at a degree of hot working of 90% or more should be set at 27%.
It is necessary to keep the temperature below 0°C.

The rough drawn wire produced under the above conditions is then cold drawn with an area reduction of 70% or more, and subsequently heat treated at a temperature of 200 to 600°C. The reason why the degree of cold working is set to 70% or more is to further improve the strength obtained at the rough drawing line and to obtain the target strength even after heat treatment. In addition, the above heat treatment is
It is intended to achieve well-balanced performance in terms of conductive properties, heat resistance properties, and strength.If the conditions are not listed in -, each of the above properties will be unbalanced and the desired properties will not be obtained. , "The second heat treatment is performed in a low temperature range, for example, 2
At around 00~300℃] m ordinary electric furnace, 300~60℃
In the high temperature range of 0°C, electrical heating is appropriately employed.

Next, the characteristics of the heat-resistant mini-RAM alloy wire for electric appliances obtained by the method of the present invention will be explained based on Examples.

〔Example〕

Melting A7 electrical grade metal with a purity of 99.8 wt% or more,
At-Zr-Fe-Si alloys having the respective composition ranges shown in Table 1 were produced using master alloys A, t-5wt%Zr, kl-5wt%Fe, and At-10wt%Si. Each of these alloys is processed by a continuous casting rolling machine to
A rough drawn wire with a wire diameter of 95 cm was obtained by casting and rolling. After the rough drawn wire was cold drawn using a continuous wire drawing machine, it was heat treated and used as a test material. Casting, rolling conditions and cold wire drawing of each sample,
The heat treatment conditions are as shown in Table 1. Further, Table 1 shows the results of determining the tensile strength, electrical conductivity, and heat resistance properties of each of the above samples.

The heat resistance properties were determined by heating each sample at 270° C. for 1 hour and expressing the ratio of the tensile strength after heating to the tensile strength before heating.

As is clear from the results shown in Figure 1, each sample of Examples 1 to J2 produced by the method of the present invention has a tensile strength of 17 & 9/
It has good properties with a conductivity of yn+n or more and a conductivity of 58%lAC3 or more, and a heat resistance property of 90% or more with a survival rate even under severe heating conditions of 270° C. On the other hand, each sample of Comparative Examples 1 to 6, which has a different composition range from the alloy according to the present invention, has a tensile strength,
It is inferior to the sample according to the present invention in either electrical conductivity or heat resistance properties. Also, Comparative Example 7 where the preparation temperature is low
compared to implementation 9115 according to the present invention, tensile strength,
It can be seen that the heat resistance is low and the effective solid solution of Zr is small. Comparative Example 8 whose rolling end temperature is higher than that of the method of the present invention, and Comparative Example 9.10 (d
It is inferior in tensile strength to Example 5, which has the same alloy composition. Comparative Example 11, in which the heat treatment temperature was 180°C, had high tensile strength but low heat resistance and unbalanced properties. Moreover, Comparative Example 12, in which the alloy composition range does not satisfy the above-mentioned formula A, is not very satisfactory in terms of 2s electric current.

As described in detail below, the method for producing a conductive heat-resistant aluminum alloy wire according to the present invention is extremely effective in obtaining an alloy wire that has good tensile strength and heat resistance properties, and particularly excellent 2# conductivity. Useful.

patent applicant Nippon Light Metal Co., Ltd. Dainichi Nippon Electric Cable Co., Ltd.

Claims (1)

[Claims] Zr O, 05~0.10 wt%, F'e0.07~
0.40 wt%. The composition range of Zr, F'e and Si is as follows: 4
0 Zr (wt%) < 5.9-9 Fe (wt
%)-58i (wt%) AL-Zr-Fe-
The Si-based alloy is melted and cast at a casting temperature of 680°C or higher, while the resulting ingot is cooled until the material temperature reaches 270°C.
At the following temperature 1, apply hot working with an area reduction rate of 90% or more to form a rough drawing line, and then form the rough drawing line with an area reduction rate of 7
Cold wire drawing is carried out at 0% or more, and the obtained wire is 200 to 600
A method for manufacturing a heat-resistant aluminum alloy wire for conductive use, characterized by heat treatment at a temperature of ℃.