JPS5831071A - Manufacture of heat resistant al alloy conductor - Google Patents

Abstract

PURPOSE:To obtain an Al alloy conductor with especially superior heat resistance by drawing a rough wire of an Al alloy contg. Zr, Fe and Si with emulsion type soluble oil having a prescribed concn. as lubricating oil at a regulated wire temp. and a regulated reduction rate of area. CONSTITUTION:A rough wire of an Al alloy consisting of 0.01-0.8% Zr, 0.07- 0.8% Fe, 0.03-0.3% Si and the balance essentially Al is drawn with emulsion type soluble oil having 10-60% concn. as lubricating oil at <=100 deg.C wire temp. and >=60% reduction rate of area. The oil reduces the generation of heat of drawing when the wire is passed through a die, and the accumulation of the heat is reduced. Thus, the occurrence of a lonnealing phenomenon is prevented, and the desired heat resistant Al alloy conductor with enhanced heat resistance is obtd. The strength and electric conductivity of the conductor are hardly deteriorated by said drawing.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing an Al-Zr heat-resistant aluminum alloy conductor, and in particular to a method for manufacturing a conductor with excellent heat resistance.

In recent years, with the increase in power transmission capacity, controlled heat-resistant aluminum alloy stranded wires have been used in overhead power transmission lines, but in order to further increase power transmission capacity under special power transmission conditions, better heat-resistant aluminum alloy conductors are needed. has been desired, and many heat-resistant aluminum alloys for electrical conductivity have been studied. Currently in practical use is Al-Z containing Zr as an active ingredient.
R-type heat-resistant aluminum? In Zr alloy, the conductivity decreases as the Zr content increases, although the amount of heat resistance dr added (= increases accordingly). Therefore, if the Zr content is increased to increase the heat resistance, the conductivity decreases, This makes it unsuitable for conductors.

In view of this, the present invention aims to improve heat resistance without significantly reducing conductivity (as a result of various studies, Al-
Compatible with Zr-based heat-resistant aluminum alloy.

In the conventional manufacturing method of heat-resistant aluminum alloy conductors, which involves drawing the rough wire by continuous or semi-continuous casting and rolling, rolling, rolling, extrusion, etc. This causes annealing hardening phenomenon, which is one of the causes of reduced heat resistance.Especially in continuous wire drawing processing, processing heat accumulates when passing through each die, and the temperature of the wire rod during processing increases considerably. As a result of the increase in heat resistance, the company found that low @ annealing hardening increases and the decrease in heat resistance also increases.As a result of further investigation, the company developed a method for manufacturing conductors with excellent heat resistance.

That is, the present invention provides ZrO,01-0,8%, Pao
, o 7-0.8%.

8 i 0.03 to 063%, the balance A1 and normal impurities Al E In the production of conductors by wire drawing nikum alloy rough wire, emulsified soluble oil with lθ ~ 60% concentration is used for wire drawing of the rough wire. is used as a lubricant, the wire temperature during wire drawing is suppressed to 100° C. or less, and the area is reduced by 60% or more.

In the present invention, the reason why the alloy composition is limited to 1st grade is as follows.

' Zr is an element added to improve heat resistance, and if the content is less than 0.01%, sufficient heat resistance cannot be obtained.
This is because if it exceeds %, the conductivity will decrease significantly. F
・ is an element added to improve strength, 0.07
If it is less than 0.8%, sufficient strength cannot be obtained, and if it exceeds 0.8%, the strength improvement effect is saturated and the conductivity is significantly lowered. Further, 8i is an element added to further improve the strength and heat resistance, and if it is less than 0.03%, the effect will be small, and if it exceeds 0.3%, the electrical conductivity will decrease significantly.

The present invention applies emulsified soluple oil with a concentration of 10 to 60% to lubricate wire drawing of rough drawn wire formed by continuous or semi-continuous casting and rolling, axillary rolling, extrusion, etc., of alloys having such a composition range. The agent used is to reduce the processing heat generated when passing through the die, reduce the accumulation of processing heat, and suppress the wire humidity during wire drawing to below 100℃, which causes the low-temperature annealing effect phenomenon. This is to prevent this and improve heat resistance.

Therefore, the concentration of emulsified soluble oil is 10 to 60%.
The reason for this is that if the oil is less than 10%, seizing occurs during wire drawing, resulting in wire drawing instinct, and if it exceeds 60%, the oil becomes like grease and the cooling ability deteriorates.

Even if a wire that generates heat during wire drawing is rapidly cooled after wire drawing, there is little improvement in heat resistance.

The reason why the wire temperature during processing is kept below 100 YPI and the surface area is reduced by 66.0% or more is to obtain sufficient strength through work hardening. , a conductor of sufficient strength cannot be obtained. Note 1. According to the method of the present invention, heat resistance can be similarly improved even when rough wire is subjected to island treatment.

The present invention will be explained below using examples.

Melt A1 metal with a purity of 99.8% and add 5% Al-5% to it.
Zr, Al-Zr with the composition shown in Table 1111 was prepared by adding Zr, Al-5%pe, Al-20%8i master alloy in various proportions.
- Melt Fe-81 alloy, belt and wheel *ll
An ingot having a cross-sectional area of 200 G- was continuously cast using a continuous casting machine, and then rolled using a continuous rolling machine to form a rough wire having a diameter of 9.5 square inches. This rough drawn wire was wire drawn using emulsified soluble oil of various concentrations as a lubricant.

The manufacturing conditions are also listed in Table 1. In addition, the wire temperature during wire drawing in Table 1 indicates the minimum temperature during wire drawing and 1jkji & knitting. Note that the same composition of rough drawn wire was subjected to continuous wire drawing using ordinary AI wire drawing oil. The conductor was manufactured. The manufacturing conditions are also listed in Table 1.

The tensile strength, electrical conductivity, and heat resistance of the conductor thus manufactured were measured. The results are shown in Table 2. still,
The tensile strength was measured using an Amsler type tensile tester, and the electrical conductivity was determined by measuring electrical resistance using a Kelvin double bridge. Moreover, the heat resistance is 0. For alloys with an O content of 1 to 0.1%, the tensile strength was determined after heating at a temperature of 180°C for 1000 hours, and for alloys with a Zr content of 0.1 to 0.2%, the tensile strength was determined after heating for 1000 hours at a temperature of 230°C. The strength was determined, and for alloys with a Zr content of 0.2 to 0.8%, the tensile strength was determined after heating at a temperature of 300°C for 400 hours.
Each value is expressed as a percentage (%) of the tensile strength before heating.

As is clear from Table 1, Table 112, and Table 11N2, the conductors manufactured by the methods of layers 1 to 12 of the present invention all had an am ratio of 51.
It has excellent performance with a tensile strength of 17.211/- and a heat resistance of 91.6% or more on 9% IACaPl, and has far superior heat resistance compared to conductors manufactured by conventional methods. I understand.

On the other hand, 1. Method of comparison of the method of the present invention and alloy composition 4
It can be seen that samples Nos. 13 to 418 are inferior in one or more of the above three characteristics.

Comparative method 413 with low Zr content has poor heat resistance <s'' Comparative method with high content 414 has poor conductivity (, Comparative method with low F content, 415 has poor tensile strength , in comparative method 416 with a high Pe content, the conductivity is
Tensile strength and heat resistance were poor in comparison method 7%17 with low 81 content, and poor tensile strength and heat resistance in comparative method 18 with high 1 content. I understand. It can also be seen that the comparative method 419, which has a small area reduction rate even though the alloy composition is the same, has a low tensile strength.

In conventional methods A20 to A20 to A431, which use an alloy with the same composition as the method of the present invention and use ordinary phantom wire drawing oil at the same area reduction rate, the wire humidity during wire drawing gradually increases, and after the final pass, The temperature was 143° C. or higher, and although the tensile strength was high due to low-temperature annealing hardening, it was found that the heat resistance was poor.

In summary, according to the present invention, the heat resistance can be significantly improved without substantially reducing the strength and conductivity of the conductor, which is an industrially significant effect.

Claims (1)

[Claims] ZrO,01~o,s%, PeO,Ofu~0,8% 8
In the production of conductors by wire drawing aluminum alloy rough drawn wire consisting of 0.03 to 0.3% j, the balance At and normal impurities, emulsified soluble oil with a concentration of 1G to 60% is poured into the wire drawing process of the rough drawn wire. Used as a lubricant to lower the wire temperature during wire drawing to 10
A method for manufacturing a heat-resistant aluminum alloy conductor, which comprises reducing the area by 60% or more while keeping the temperature below 0°C.