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CN-121718810-B - High-strength heat-resistant Al-Cu-Zn-Mg-Sc-Hf alloy and preparation method thereof

CN121718810BCN 121718810 BCN121718810 BCN 121718810BCN-121718810-B

Abstract

The application belongs to the technical field of preparation of high-strength heat-resistant aluminum alloy, and particularly relates to a high-strength heat-resistant Al-Cu-Zn-Mg-Sc-Hf alloy and a preparation method thereof, wherein the preparation method comprises the following steps of S1, obtaining an Al-Cu-Zn-Mg-Sc-Hf alloy casting blank, homogenizing, hot rolling and solid solution the Al-Cu-Zn-Mg-Sc-Hf alloy casting blank to obtain a first alloy, and performing electric pulse aging on the first alloy to obtain a second alloy, S3, performing electric pulse deformation on the second alloy and aging on the second alloy to obtain the Al-Cu-Zn-Mg-Sc-Hf alloy according to mass percentage, wherein the components of the Al-Cu-Zn-Mg-Hf alloy casting blank are Cu 3.50-4.50%, zn is 3.0%, mg is 1.20% -1.50%, zr is 0.10% -0.20%, sc is 0.05% -0.15%, hf is 0.10% -0.30%, and the balance is Al and unavoidable impurities. The application designs a method for cooperatively improving the room temperature mechanical property and heat resistance of an alloy by adopting a regulation and control means of combining the composite microalloying with the electric pulse deformation and the aging.

Inventors

  • SHI ZHIYUE
  • QIN JIN
  • YAN ZHIJIE
  • WANG RUI
  • YU ZHIQIANG

Assignees

  • 中北大学

Dates

Publication Date
20260505
Application Date
20260227

Claims (6)

  1. 1. The preparation method of the high-strength heat-resistant Al-Cu-Zn-Mg-Sc-Hf alloy is characterized by comprising the following steps of: S1, obtaining an Al-Cu-Zn-Mg-Sc-Hf alloy casting blank, homogenizing, hot-rolling and solid-dissolving the Al-Cu-Zn-Mg-Sc-Hf alloy casting blank to obtain a first alloy, wherein the Al-Cu-Zn-Mg-Sc-Hf alloy casting blank comprises, by mass, 3.50% -4.50% of Cu, 3.0% -4.0% of Zn, 1.20% -1.50% of Mg, 0.10% -0.20% of Zr, 0.05% -0.15% of Sc, 0.10% -0.30% of Hf, and the balance of Al and unavoidable impurities; S2, performing electric pulse aging on the first alloy to obtain a second alloy; In the step S2, the temperature of the electric pulse aging is 150-180 ℃, the time of the electric pulse aging is 7-9h, and the cooling mode of the electric pulse aging is water cooling; S3, carrying out electric pulse deformation and reaging on the second alloy to obtain an Al-Cu-Zn-Mg-Sc-Hf alloy; In the step S3, the pulse voltage of the electric pulse deformation and reaging is 10-14V, the pulse width of the electric pulse deformation and reaging is 20-25 mu S, and the frequency of the electric pulse deformation and reaging is 300-350Hz; in the step S3, the temperature of the electric pulse deformation and reaging is 350-400 ℃, the time of the electric pulse deformation and reaging is 1-3h, and the cooling mode of the electric pulse deformation and reaging is water cooling; In the step S3, the strain amount of the electric pulse deformation and the reaging is 10% -20%.
  2. 2. The method for preparing the high-strength heat-resistant Al-Cu-Zn-Mg-Sc-Hf alloy according to claim 1, wherein in the step S1, the specific mode of obtaining the Al-Cu-Zn-Mg-Sc-Hf alloy casting blank is that according to the component proportion raw materials of the Al-Cu-Zn-Mg-Sc-Hf alloy casting blank, the raw materials comprise pure Al, mg, zn cast ingots, al-50Cu, al-4Zr, al-3Sc and Al-5Hf intermediate alloys, and the raw materials are smelted and cast in a 720-760 ℃ resistance furnace to obtain the Al-Cu-Zn-Mg-Sc-Hf alloy casting blank.
  3. 3. The method for producing a high-strength heat-resistant Al-Cu-Zn-Mg-Sc-Hf alloy according to claim 1, wherein the homogenization temperature in the step S1 is 470-510 ℃, and the homogenization time is 28-36 hours.
  4. 4. The high-strength heat-resistant Al-Cu-Zn-Mg-Sc-Hf alloy, characterized in that the high-strength heat-resistant Al-Cu-Zn-Mg-Sc-Hf alloy is prepared by the preparation method of any one of claims 1-3.
  5. 5. The high-strength heat-resistant Al-Cu-Zn-Mg-Sc-Hf alloy according to claim 4, wherein the tensile strength of the Al-Cu-Zn-Mg-Sc-Hf alloy at room temperature is not less than 535MPa, and the elongation of the Al-Cu-Zn-Mg-Sc-Hf alloy at room temperature is not less than 9.0%.
  6. 6. The high-strength heat-resistant Al-Cu-Zn-Mg-Sc-Hf alloy according to claim 4, wherein the tensile strength of the Al-Cu-Zn-Mg-Sc-Hf alloy at 400 ℃ high temperature is not less than 95MPa, and the elongation of the Al-Cu-Zn-Mg-Sc-Hf alloy at 400 ℃ high temperature is not less than 16.5%.

Description

High-strength heat-resistant Al-Cu-Zn-Mg-Sc-Hf alloy and preparation method thereof Technical Field The application relates to the technical field of preparation of high-strength heat-resistant aluminum alloy, in particular to a high-strength heat-resistant Al-Cu-Zn-Mg-Sc-Hf alloy and a preparation method thereof. Background An A1-Cu-Mg (2 xxx series) alloy is a typical lightweight material, and has been the main research focus due to its excellent specific strength, excellent corrosion resistance, and good weldability. At present, the deep space exploration development and the technical innovation of weaponry require that the strength of the Al-Cu-Mg alloy exceeds 100MPa under the service condition of 400 ℃. The aircraft faces severe conditions of more than 1000 ℃ in the service process, key parts such as aircraft skins and inner bearing parts can also be more than 400 ℃ under the condition of protecting a heat insulation layer, and precipitated phases in the alloy are seriously coarsened, so that the aircraft is quickly softened and fails. Therefore, the thermal stability of the precipitated phase will be a significant problem in the field of aluminum alloys and light alloys. Studies have shown that commercial 2xxx series aluminum alloys are suitable only at 200 ℃ and far below 400 ℃ service requirements. Therefore, researchers mainly enhance the thermal stability of Al-Cu-Mg alloy by stabilizing the precipitated phase and constructing a low-energy interface. Trace elements are added into the Al-Cu-Mg alloy to promote solute atom interface segregation and improve the thermal stability of a precipitated phase, and the heat-resistant temperature of the alloy can reach 350 ℃. Coarsening of the precipitated phase easily occurs when the service temperature exceeds 350 ℃. In the prior art, the precipitated phase in the alloy is unstable, so that the thermal resistance of the aluminum alloy is deteriorated, and the strength of the traditional heat treatment reinforced aluminum alloy is insufficient in high-temperature service, so that a high-strength heat-resistant Al-Cu-Mg alloy and a preparation method thereof are needed to solve the problems. Disclosure of Invention The application provides a preparation method of a high-strength heat-resistant Al-Cu-Zn-Mg-Sc-Hf alloy, which comprises the following steps of S1, obtaining an Al-Cu-Zn-Mg-Sc-Hf alloy casting blank, homogenizing, hot-rolling and solid-dissolving the Al-Cu-Zn-Mg-Sc-Hf alloy casting blank to obtain a first alloy, wherein the Al-Cu-Zn-Mg-Sc-Hf alloy casting blank comprises, by mass, 3.50% -4.50% of Cu, 3.0% -4.0% of Zn, 1.20% -1.50% of Mg, 0.10% -0.20% of Zr, 0.05% -0.15% of Sc, 0.10% -0.30% of Hf and the balance of Al and unavoidable impurities, S2, performing electric pulse aging on the first alloy to obtain a second alloy, and performing electric pulse deformation on the second alloy to obtain the Al-Cu-Zn-Mg-Sc-Hf alloy. In the step S1, the specific mode of obtaining the Al-Cu-Zn-Mg-Sc-Hf alloy casting blank is that according to the component proportion raw materials of the Al-Cu-Zn-Mg-Sc-Hf alloy casting blank, the raw materials comprise pure aluminum ingots, pure magnesium ingots, pure silver ingots, aluminum intermediate alloys and rare earth alloys, and the raw materials are smelted and cast in a 720-760 ℃ resistance furnace to obtain the Al-Cu-Zn-Mg-Sc-Hf alloy casting blank. As a preferable scheme of the preparation method of the high-strength heat-resistant Al-Cu-Zn-Mg-Sc-Hf alloy, in the step S1, the homogenization temperature is 470-510 ℃, and the homogenization time is 28-36h. As a preferable scheme of the preparation method of the high-strength heat-resistant Al-Cu-Zn-Mg-Sc-Hf alloy, in the step S2, the temperature of electric pulse aging is 150-180 ℃, the time of electric pulse aging is 7-9h, and the cooling mode of electric pulse aging is water cooling. As a preferable scheme of the preparation method of the high-strength heat-resistant Al-Cu-Zn-Mg-Sc-Hf alloy, in the step S3, the pulse voltage of electric pulse deformation re-aging is 10-14V, the pulse width of the electric pulse deformation re-aging is 20-25 mu S, and the frequency of the electric pulse deformation re-aging is 300-350Hz. As a preferable scheme of the preparation method of the high-strength heat-resistant Al-Cu-Zn-Mg-Sc-Hf alloy, in the step S3, the temperature of electric pulse deformation re-aging is 350-400 ℃, the time of electric pulse deformation re-aging is 1-3h, and the cooling mode of electric pulse deformation re-aging is water cooling. As a preferable scheme of the preparation method of the high-strength heat-resistant Al-Cu-Zn-Mg-Sc-Hf alloy, in the step S3, the strain quantity of the electric pulse deformation re-aging is 10% -20%. The application also provides a high-strength heat-resistant Al-Cu-Zn-Mg-Sc-Hf alloy, which is prepared by adopting the preparation method of the high-strength heat-resistant Al-Cu-Zn-Mg-Sc-Hf alloy. As the preferable scheme