JPS6013046A - Heat-resistant aluminum alloy for electric conduction and its manufacture - Google Patents

Abstract

PURPOSE:To manufacture an Al alloy conductor with high electric conductivity, high strength and superior heat resistance by casting an Al alloy having a specified composition contg. Ni and Fe, hot rolling and cold drawing the cast alloy, and heat treating it under proper conditions. CONSTITUTION:An Al alloy consisting of 1.5-6.0wt% Ni, 0.3-<2.0wt% Fe and the balance Al with ordinary impurities is continuously or semicontinuously cast. The cast alloy is hot rolled and cold drawn, and it is heat treated at 100- 400 deg.C for 0.5-10hr to obtain a heat-resistant Al alloy for electric conduction. Among said constituent elements, Ni is dispersed in the Al matrix in the form of NiAl3 to improve the strength and heat resistance, and Fe strengthens the Al matrix and improves the strength of the alloy. Said amounts of Ni and Fe do not deteriorate the workability and electric conductivity. Said proper heat treatment controls the strength and electric conductivity and provides heat resistance.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heat-resistant aluminum alloy for 6N and a method for producing the same, and in particular, it has a strength equivalent to that of a conventional heat-resistant aluminum alloy for conductive use (Al1-Zr alloy), and has electrocardiographic properties. The purpose of the present invention is to provide an aluminum alloy conductor that has excellent heat resistance without significantly reducing the heat resistance.

Conventionally, solid solution type heat resistant aluminum alloys that utilize the solid solution ZR heat resistance mechanism of △ and e-Zr alloys have been used for power transmission lines that require heat resistance, but in recent years, due to the increase in power demand, heat resistance Improvements are now required. In order to cope with this, a conductive heat-resistant aluminum alloy with increased solid solution 1rfl, and a precipitated ZRA instead of the heat resistant mechanism of solid solution ZR.
) A highly heat-resistant aluminum alloy for conductive use that utilizes a heat-resistant mechanism has been developed.

However, an increase in solid solution Zrω leads to a decrease in electrical conductivity, and in order to utilize the heat resistance mechanism of precipitated Zr, it is necessary to
Because it requires long-term heat treatment at a temperature of 450°C,
It had the disadvantage of high cost.

Furthermore, the temperature and humidity that can be used for these alloys when energized is approximately 300° C., and further improvement in heat resistance is strongly desired.

In view of this, as a result of various researches, the present invention has developed a heat-resistant aluminum alloy for electrocardiograms that has strength equivalent to that of conventional heat-resistant aluminum alloys for conductive use, and has far superior heat resistance without significantly reducing conductivity. , we have developed a manufacturing method for it.

That is, the alloy of the present invention contains Ni, 5 to 0 wt% (hereinafter referred to as W and % as %), more than 0.8% and less than 2.0% Fe, and the balance consists of normal impurities. It is characterized by:

In addition, the manufacturing method of the present invention uses 1.5 to 6.0% Ni and Fe09.
Continuously or semi-continuously cast aluminum alloy containing more than 8% and less than 2.0% and the remainder (and normal impurities)
(~100~400 after hot rolling and cold wire drawing
It is characterized by heat treatment at a temperature of 0.5 to 10 hours. However, the reason why the alloy composition is limited as described above in the present invention is as follows.

The reason why the N1 content right foot was limited to 1.5 to 6.0 was because of the addition of N1 (Is it because it improves strength and heat resistance as a eutectic structure with Ni AJ3 dispersed in the matrix? If the content is less than 1.5%, heat resistance is insufficient, and if it exceeds 6.0%, primary crystal NiA,
This is because the dendrite phase of e3 is crystallized, which not only impairs workability but also greatly reduces ductility and electrical conductivity. In addition, the reason why the Fe content was limited to more than 0.8% and less than 2.0% was because the /l matrix was strengthened by the addition of Fe.
This is to further improve the strength, but the content is 0.
This is because if it is less than 8%, the effect is insufficient, and if it is more than 2.0%, the conductivity will decrease significantly.

The alloy of the present invention has the above-mentioned composition, and is roughly drawn by conventional continuous or semi-continuous casting and hot rolling, and then cold drawn to a desired wire diameter, and then heated at a temperature of 100 to 400°C. It is produced by heat treatment for 0.5 to 10 hours.

0.5-1 at a temperature of 100-400°C after cold wire drawing
The reason for heat treatment for 0 hours is to adjust the strength and conductivity as well as impart heat resistance, and even if the temperature is below 100°C or the treatment time is less than 0.5 hours, the conductivity does not recover and the heat resistance is low. Moreover, even if the temperature exceeds 400° C. or the processing time exceeds 10 hours, the strength decreases significantly.

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

Electrical A with a purity of 99.8% (melt the base metal and add A to this
(-6% Fe master alloy and A, l!-10% Ni master alloy were added to melt the alloy having the composition shown in Table 1, and then cast and hot-rolled by belt-and-wheel type continuous casting and rolling. A rough drawn wire with a diameter of 8.0 mm was obtained, and this was processed into a wire with a diameter of 4.8 mm by cold wire drawing.

After heating this wire at various temperatures, the conductivity and
Tensile strength and 10% softening rate were measured. These results are also listed in Table 1 in comparison with conventional A, e-Zr alloys.

The 10% softening temperature is the temperature at which the strength decreases by 10% after one hour of heat treatment.

Morihe acceptance i #″-″ zI-he no dimension LO ■ ト■a: +−−−,−−−−
As is clear from Table 1, the alloy of the present invention was prepared using the method of the present invention (N
o, 1 to 6), the conductivity of the product manufactured is 56
It exhibits properties such as tensile strength of 17.5 Kil/mm2 or higher and 10% softening temperature of 390°C or higher, compared to conventional methods (
Compared to No. 15), it can be seen that it has the same strength without significantly lowering the conductivity and has much better heat resistance.

On the other hand, as can be seen from the comparative method (No. 7 to 14), alloys outside the composition range of the present invention alloy are inferior in conductivity, tensile strength, and heat resistance even if manufactured by the present invention method. In particular, comparative method No. 007 with a low N1 content did not improve heat resistance, comparative methods No. 9 with a low Fe content did not improve strength, and comparative method No. 18 with a high Ni content and comparative method No. 9 with a high Fe content ( For both NO and 10), the decrease in conductivity is significant.

Furthermore, as can be seen from the comparative method (NO, 11 to 14), even if the composition of the alloy is within the composition range of the present invention alloy, if the heat treatment conditions after wire drawing are out of range, the conductivity, tensile strength, or heat resistance will be affected. is inferior.

As described above, according to the present invention, it is possible to obtain an alloy that has strength equivalent to that of conventional heat-resistant aluminum alloys, and has far superior heat resistance without significantly reducing conductivity. It has a significant effect in that it can be used to increase power transmission capacity.

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Claims (2)

[Claims] (1) Ni1.5~G, OW% and FcO, 8wt
% and less than 2.0 wt%, and the remainder (and normal impurities). (2) Ni 1.5~e, owt% and FeO98
An aluminum alloy consisting of wt% or more 2 and less than Owt%, and the balance A, 2 and ordinary impurities is continuously or semi-continuously cast, and after EM and cold wire drawing, 1
A method for producing a heat-resistant aluminum alloy for conductive use, which comprises heat-treating at a temperature of 00 to 400°C for 0.5 to 10 hours.