JPS634893B2 - - Google Patents

Description

[Detailed description of the invention]

INDUSTRIAL APPLICATION FIELD The present invention relates to an aluminum alloy suitably used for manufacturing overhead power transmission lines and the like. Conventional technology Traditionally, when transmitting large amounts of power at high voltage to remote locations, it was necessary to increase the power transmission capacity while reducing the weight of the wire itself, and steel-core aluminum stranded wires (ACSR) were used. There are many. Particularly in cases where heat resistance is required, such as in large-capacity power transmission, heat-resistant aluminum alloys for electrical applications are used, which have added a small amount of zirconium to improve heat resistance (TACSR). However, such zirconium-added alloys do not have sufficient tensile strength, so the strength can be improved by adding several types selected from iron, silicon, magnesium, cobalt, nickel, beryllium, rare earth metals, etc. A high-strength, heat-resistant aluminum alloy has been developed and put into practical use as steel-core high-strength, heat-resistant aluminum alloy stranded wire (KTACSR). However, such high-strength, heat-resistant aluminum alloys require the addition of large amounts of subcomponents to increase mechanical strength, and are often subjected to annealing or solution treatment during the rough drawing stage to increase heat resistance and conductivity. Moreover, complicated indexes were required, such as intermediate annealing after wire drawing. Therefore, there were disadvantages in that the electrical conductivity was not sufficient, the corrosion resistance was very poor, and the manufacturing cost of the electric wire was high. Problems to be Solved The present invention improves the above-mentioned drawbacks and provides a steel-core aluminum stranded wire that has excellent properties in terms of mechanical strength, heat resistance, electrical conductivity, and corrosion resistance. The purpose is to provide an aluminum alloy. Means for Solving the Problems The purpose of the present invention is to solve the following problems: iron 0.2~0.6% by weight, magnesium 0.03~0.15% by weight, copper 0.06~0.3% by weight.
An alloy consisting of 0.04 to 0.2% by weight of zirconium and the balance of aluminum and impurities such as silicon in amounts normally contained in aluminum base metal, where the total amount of iron, magnesium, and copper is 0.7% by weight or less. It is also achieved by an aluminum alloy in which the weight ratio of copper and magnesium is within the range of 1.8 to 2.3. In the alloy of the present invention, the addition of iron is effective in improving heat resistance, conductor strength, and wire drawability, but if the amount is less than 0.2% by weight, it has little effect; If it exceeds %, the effect will not increase significantly and on the contrary, it will be disadvantageous in terms of conductivity and corrosion resistance. Addition of magnesium improves the strength and corrosion resistance of the conductor, but if the amount is less than 0.03% by weight it has little effect, while if it exceeds 0.15% by weight it is effective but the conductivity and heat resistance are significantly reduced. Therefore, it is undesirable. Copper is used to increase the strength of conductors, but
If the amount added is less than 0.06% by weight, the effect is not significant;
On the other hand, if it exceeds 0.3% by weight, corrosion resistance, heat resistance, and conductivity will be significantly reduced. Furthermore, if the amount of zirconium added is less than 0.04% by weight, the improvement in heat resistance will be insufficient, and if it exceeds 0.2% by weight, the heat resistance will be significantly reduced. In addition, the total amount of iron, magnesium and copper
If it exceeds 0.7% by weight, the conductivity and corrosion resistance will be greatly reduced, which is undesirable for practical use. When the weight ratio of copper to magnesium is within the range of 1.8 to 2.3, the decrease in corrosion resistance caused by the presence of copper is minimized by the presence of magnesium, and an alloy with a good balance of corrosion resistance and heat resistance can be obtained. If this value is larger than 2.3, the corrosion resistance will be unsatisfactory, and if this value is smaller than 1.8, the heat resistance will be insufficient. Example Electrical aluminum ingot (silicon 0.04% by weight,
0.12% by weight of iron, 0.001% by weight of copper, 0.001% by weight of manganese, 0.001% by weight of titanium and vanadium, and 99.83% by weight of aluminum) were melted in an electric furnace, and each component was added to form the composition shown in Table 1. The alloy was melted and cast using a copper mold with a diameter of 30 mm. These ingots were hot rolled into rough drawn wires with a diameter of 9.5 mm, which were then cold drawn to a diameter of 4.0 mm to obtain wire conditions for testing. Table 2 shows the results of measuring the tensile strength, electrical conductivity, heat resistance, and corrosion resistance of the test specimens thus obtained. The test conditions for each test are as follows. Tensile strength: Based on Instron type tensile tester. Conductivity: by Kelvin double bridge. Heat resistance: Displayed as the ratio of the tensile strength after heating to the tensile strength before heating when heat treated at 230°C for 1 hour. Corrosion resistance: SO ₂ concentration using a sulfur dioxide gas corrosion tester
It is expressed as the ratio of the tensile strength after 60 cycles of 8 hours of operation + 16 hours of rest at 500PPM to the tensile strength before corrosion.

【table】

【table】

[Table] Yes.
In Tables 1 and 2, the characteristics of alloys No. 1 to No. 8, which are examples of the present invention, are compared with those of alloys No. 9 to No. 15, which are comparative examples. The comparative example alloys all have tensile strength, electrical conductivity,
The properties of heat resistance and corrosion resistance are unbalanced, resulting in unsatisfactory performance. However, the alloys of the present invention all exhibit excellent corrosion resistance of 97.8% or higher, and Tensile strength,
The conductivity and heat resistance are also comparable to those of the comparative examples. This shows that the aluminum alloy of the present invention has an excellent balance of properties that could not be achieved with conventional techniques. Effects of the Invention The high-strength heat-resistant aluminum alloy of the present invention contains iron, magnesium, copper, and zirconium in specific proportions, and has high tensile strength, conductivity, and This method has the advantage that it is possible to obtain electric wires with excellent heat resistance and corrosion resistance. Therefore, the conductive wire manufactured using the alloy of the present invention not only has a good balance of properties but also has the advantage of being low in manufacturing cost.

Claims (1)

[Claims] 1 Iron 0.2-0.6% by weight, Magnesium 0.03-0.15
wt%, copper 0.06~0.3 wt%, zirconium 0.04~
An alloy consisting of 0.2% by weight and the balance of aluminum and impurities such as silicon in amounts normally contained in aluminum bullion, in which the total amount of iron, magnesium, and copper is 0.7% by weight or less, and the balance is aluminum and impurities such as silicon in an amount normally contained in aluminum bullion, and the total amount of iron, magnesium, and copper is 0.7% by weight or less, and copper and magnesium A high-strength, heat-resistant aluminum alloy with excellent electrical conductivity and corrosion resistance, characterized by a weight ratio of 1.8 to 2.3.