Method for preparing high-strength, high-conductivity and heat-resistant aluminum alloys

Abstract

The invention discloses a method for preparing high-strength, high-conductivity and heat-resistant aluminum alloys. The method for preparing the high-strength, high-conductivity and heat-resistant aluminum alloys comprises the following steps: putting pure aluminum powder into a ball mill, ball milling, then putting the aluminum powder after ball milling into a cold isostatic pressure encapsulation sleeve and carrying cold isostatic pressure treatment, and putting pressure blanks after carrying out cold isostatic pressure treatment in a protective atmosphere to carry out sintering densification at a sintering temperature of 600-640 DEG C; and carrying out hot squeezing and cold drawing on sintered aluminum bars to obtain the high-strength, high-conductivity and heat-resistant aluminum alloys. The high-strength, high-conductivity and heat-resistant aluminum alloys prepared by the method are free of other alloy metals and just contain a nano-sized tiny oxide substance point which is used as a strengthening phase, and the strengthening phase is tiny and uniform, so that the strength of the material is improved, and the influence on the conductivity of the material is small; the oxide strengthening phase can stably exist at the high temperature, so that the recovery and re-crystallization of the material can be remarkably avoided, and the growth of crystal grains is avoided; therefore, the strength can be retained at the high temperature; the heat resistance of the material is remarkably improved.

Description

technical field [0001] The invention relates to the field of powder metallurgy, and relates to a method for preparing a high-strength, high-conductivity, heat-conduction, and high-heat-resistance aluminum alloy with excellent performance by adopting a powder metallurgy method. It is suitable for the production of various aluminum alloys that require high strength and high conductivity. Background technique [0002] Copper is a common material for wires and cables, with good conductivity and strength, but copper resources in my country are very scarce and expensive. Aluminum is also a good conductive metal material. The conductivity of pure aluminum is 64IACS%, and it is cheap and easy to process, so it has been widely concerned in the cable industry. However, the texture of pure aluminum is relatively soft, the tensile strength is only 60-70MPa, and the yield strength is 20MPa, which is difficult to meet the needs of use. The current general practice is to add a small amou...

AI Technical Summary

Problems solved by technology

However, the added alloy elements will greatly affect the conductivity of aluminum, such as 6061 aluminum alloy, in which the content of Mg is 0.8-1.2%, the content of Si is 0.4-0.8%, its tensile strength can reach 160MPa, but its conductivity is only 57IACS %, a drop of 11% relative to 64IACS% for pure aluminum

And its heat resistance is poor, when the temperature rises during power transmission, its strength decreases rapidly, which will cause safety hazards

Therefore, at present, my country's aluminum alloy high-voltage overhead long-distance transmission lines mainly use steel-cored aluminum stranded wires, and steel wires are added to the core of the aluminum stranded wires to play a supporting role. However, this method increases the quality of the wires and increases the erection cost.

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