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CN-122012979-A - High-strength corrosion-resistant aluminum alloy extrusion material and preparation method thereof

CN122012979ACN 122012979 ACN122012979 ACN 122012979ACN-122012979-A

Abstract

The invention discloses a high-strength corrosion-resistant aluminum alloy extrusion material and a preparation method thereof, and relates to the technical field of novel aviation aluminum alloy materials. The method comprises the steps of firstly melting high-purity aluminum, adding Si, fe, cu, mn, cr, zn, ti and Mg to alloy, introducing Ti-B-C nano intermediate alloy, sc, zr, lanthanum-rich mixed rare earth and needle-shaped nano wollastonite into a melt, applying high-energy ultrasonic and pulse magnetic field synergistic treatment to realize in-situ generation and uniform dispersion of nano phases, carrying out sectional homogenization heat treatment after semicontinuous casting, carrying out hot extrusion molding, and finally carrying out solution quenching and low-temperature preaging on extruded profiles in sequence, applying pulse electric field assistance in an atmosphere furnace, and introducing Yb-Ce rare earth precursor and silane modified nano SiO 2 to carry out grain boundary regulation and passivation treatment. The aluminum alloy extrusion material has both ultrahigh mechanical properties and excellent corrosion resistance.

Inventors

  • SHEN QIAOPING
  • FANG YIBO
  • ZHOU ZHONGWEI
  • Rao Qingrong

Assignees

  • 湖北亨威铝业有限公司

Dates

Publication Date
20260512
Application Date
20260415

Claims (10)

  1. 1. The preparation method of the high-strength corrosion-resistant aluminum alloy extrusion material is characterized by comprising the following steps of: (1) Melting a high-purity aluminum ingot, sequentially adding high-purity Si, high-purity Fe, high-purity Cu, high-purity Mn, high-purity Cr, high-purity Zn and high-purity Ti, carrying out heat preservation and stirring until the high-purity Si, the high-purity Fe, the high-purity Cu, the high-purity Mn, the high-purity Cr, the high-purity Zn and the high-purity Ti are completely melted, then adding a sodium-free refining agent for refining, degassing and deslagging, adding high-purity Mg after refining, carrying out heat preservation and stirring until the high-purity Mg is completely melted, and removing surface scum after standing to obtain an aluminum melt; (2) Adding Ti-B-C nano intermediate alloy, high-purity metal Sc, high-purity metal Zr, lanthanum-rich mixed rare earth and needle-shaped nano wollastonite into an aluminum melt, then applying high-energy ultrasonic and pulse magnetic field treatment, controlling the temperature of the melt in the treatment process, preserving heat and standing after the treatment is finished, and removing surface scum; (3) Cooling the melt obtained in the step (2), performing semicontinuous casting to obtain an ingot, removing a head and tail riser and a surface segregation layer of the ingot after air cooling, performing sectional heating and heat-preserving heat treatment on the ingot, performing forced air cooling, sawing into an extrusion blank, performing hot extrusion in a preheated extrusion cylinder and an extrusion die after heating, and performing online cooling on an extrusion outlet profile to obtain an extrusion profile; (4) Carrying out solution treatment on the extruded profile, carrying out water quenching after heat preservation, then carrying out low-temperature pre-ageing treatment, and cooling along with a furnace after heat preservation; (5) And (3) placing the section bar obtained in the step (4) into an atmosphere heat treatment furnace, introducing high-purity argon, introducing Yb (acac) 3 -Ce(acac) 3 composite rare earth organic precursor and silane modified nano SiO 2 aerosol, applying a pulse electric field, carrying out heat preservation treatment, and then carrying out heating, heat preservation and cooling to obtain the high-strength corrosion-resistant aluminum alloy extrusion material.
  2. 2. The method for preparing a high-strength corrosion-resistant aluminum alloy extrusion material according to claim 1, wherein in the step (2), the addition amount of the Ti-B-C nano intermediate alloy is 0.3% -0.8% of the mass of the aluminum melt.
  3. 3. The method for preparing the high-strength corrosion-resistant aluminum alloy extrusion material according to claim 1, wherein in the step (2), the molar ratio of Ti to B to C in the Ti-B-C nano intermediate alloy is 3:2:1, and the particle size of the powder is 50-100 nm.
  4. 4. The method for preparing a high-strength corrosion-resistant aluminum alloy extrusion material according to claim 1, wherein in the step (2), the addition amount of the high-purity metal Sc is 0.05% -0.15% of the mass of the aluminum melt.
  5. 5. The method for preparing a high-strength corrosion-resistant aluminum alloy extrusion material according to claim 1, wherein in the step (2), the high-purity metal Zr is added in an amount of 0.08% -0.20% of the mass of the aluminum melt.
  6. 6. The method for preparing the high-strength corrosion-resistant aluminum alloy extrusion material according to claim 1, wherein in the step (2), the mass ratio of the lanthanum-rich mixed rare earth to the needle-shaped nano wollastonite is 1 (1.5-3.0).
  7. 7. The method for preparing a high-strength corrosion-resistant aluminum alloy extrusion material according to claim 1, wherein in the step (4), the solution treatment temperature is 540-550 ℃, and the solution treatment time is 20-30 min.
  8. 8. The method for preparing the high-strength corrosion-resistant aluminum alloy extrusion material according to claim 1, wherein in the step (5), the mass ratio of the Yb (acac) 3 -Ce(acac) 3 composite rare earth organic precursor to the silane modified nano SiO 2 aerosol is 1 (1.5-3.0).
  9. 9. The method for producing a high-strength corrosion-resistant aluminum alloy extruded material according to claim 1, wherein in the step (5), the mass ratio of Yb to Ce in the Yb (acac) 3 -Ce(acac) 3 composite rare earth organic precursor is 2:1.
  10. 10. A high strength corrosion resistant aluminium alloy extrusion material, characterized in that it is prepared by the method of any one of the preceding claims 1 to 9.

Description

High-strength corrosion-resistant aluminum alloy extrusion material and preparation method thereof Technical Field The invention relates to the technical field of novel aviation aluminum alloy materials, in particular to a high-strength corrosion-resistant aluminum alloy extrusion material and a preparation method thereof. Background With the rapid iterative upgrade of the global aerospace industry, the new generation of high-end equipment such as civil large airplanes, military fighters, nearby space aircrafts and the like has brought forward the severe core requirements on structure light weight, high bearing reliability and long service life. The aluminum alloy is used as a lightweight metal structural material which is most widely applied and mature in the aerospace field, and takes up irreplaceable application positions in core aviation structural members such as a fuselage bearing frame, wing ribs, an undercarriage auxiliary bearing structure, an airborne equipment mounting beam, a cabin sealing connecting piece, an aviation engine peripheral member and the like by virtue of low density, high specific strength, excellent cold and hot forming performance, good welding performance and environmental protection characteristic of full life cycle recovery. The Al-Mg-Si series (6000 series) aluminum alloy has the advantages of excellent heat treatment strengthening effect, complex section extrusion formability, medium strength and basic corrosion resistance, becomes a preferred base material of a medium-strength thin-wall and special-section extrusion structural member in a novel aviation aluminum alloy material system, and is a research, development and industrialization application hot spot in the current global aviation lightweight material field. However, the existing Al-Mg-Si aluminum alloy applied to the aviation field still has a core performance short plate, the mechanical strength and the corrosion resistance of the core performance short plate cannot be matched with the severe use requirements of new generation aviation equipment, and a remarkable improvement space exists. In the aspect of mechanical strength, the conventional aviation-grade aluminum alloy applied in large scale in the prior aviation field has insufficient mechanical strength, can be only used for non-main bearing interior trim parts and auxiliary structural parts, and cannot meet the high-strength requirement of aviation main bearing structural parts. Disclosure of Invention The invention aims to provide a high-strength corrosion-resistant aluminum alloy extrusion material and a preparation method thereof, so as to solve the technical problems of the background technology. The aluminum alloy extrusion material prepared by the invention has excellent mechanical strength and corrosion resistance. In order to achieve the above purpose, the present invention provides the following technical solutions: A preparation method of a high-strength corrosion-resistant aluminum alloy extrusion material comprises the following steps: (1) Melting a high-purity aluminum ingot, sequentially adding high-purity Si, high-purity Fe, high-purity Cu, high-purity Mn, high-purity Cr, high-purity Zn and high-purity Ti, carrying out heat preservation and stirring until the high-purity Si, the high-purity Fe, the high-purity Cu, the high-purity Mn, the high-purity Cr, the high-purity Zn and the high-purity Ti are completely melted, then adding a sodium-free refining agent for refining, degassing and deslagging, adding high-purity Mg after refining, carrying out heat preservation and stirring until the high-purity Mg is completely melted, and removing surface scum after standing to obtain an aluminum melt; (2) Adding Ti-B-C nano intermediate alloy, high-purity metal Sc, high-purity metal Zr, lanthanum-rich mixed rare earth and needle-shaped nano wollastonite into an aluminum melt, then applying high-energy ultrasonic and pulse magnetic field treatment, controlling the temperature of the melt in the treatment process, preserving heat and standing after the treatment is finished, and removing surface scum; (3) Cooling the melt obtained in the step (2), performing semicontinuous casting to obtain an ingot, removing a head and tail riser and a surface segregation layer of the ingot after air cooling, performing sectional heating and heat-preserving heat treatment on the ingot, performing forced air cooling, sawing into an extrusion blank, performing hot extrusion in a preheated extrusion cylinder and an extrusion die after heating, and performing online cooling on an extrusion outlet profile to obtain an extrusion profile; (4) Carrying out solution treatment on the extruded profile, carrying out water quenching after heat preservation, then carrying out low-temperature pre-ageing treatment, and cooling along with a furnace after heat preservation; (5) And (3) placing the section bar obtained in the step (4) into an atmosphere heat treatment furnace, introducing h