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CN-122013004-A - Solid solution heating-step quenching process for novel high-magnesium-content aluminum alloy

CN122013004ACN 122013004 ACN122013004 ACN 122013004ACN-122013004-A

Abstract

The invention discloses a solution heating-step quenching process of novel high-magnesium-content aluminum alloy, which comprises the following steps of (1) preparing a thermal deformation processing material of the novel high-magnesium-content aluminum alloy in a rolling or extrusion mode, carrying out solution heating heat preservation treatment at 460-545 ℃ per 30-150 min, (2) carrying out first-stage quenching on the thermal deformation processing material subjected to solution heating in an air cooling mode, cooling to 420-450 ℃, cooling at a cooling speed of 2-8 ℃ per second, and transferring the time from solution to the first-stage quenching for not more than 15s, (3) carrying out second-stage quenching on the thermal deformation processing material subjected to the first-stage quenching, cooling to 180-230 ℃, cooling at a cooling speed of 40-75 ℃ per second, (4) carrying out third-stage quenching on the thermal deformation processing material subjected to the second-stage quenching, cooling to 30-50 ℃ per second, and cooling at a cooling speed of 2-8 ℃, and (5) carrying out pre-deformation and ageing treatment on the processing material subjected to step quenching. The solid solution heating-step quenching process can remarkably reduce the quenching cracking risk of the processed material.

Inventors

  • YU MINGYANG
  • WEN KAI
  • LI YANAN
  • ZHU KAI
  • LI YING
  • SHI GUOHUI
  • LIU QILONG
  • LI CHANGLIN
  • GAO GUANJUN
  • LI XIWU
  • XIONG BAIQING
  • ZHANG YONGAN
  • LI ZHIHUI
  • YAN HONGWEI
  • LIU HONGWEI
  • YAN LIZHEN

Assignees

  • 有研工程技术研究院有限公司

Dates

Publication Date
20260512
Application Date
20260206

Claims (11)

  1. 1. A novel solid solution heating-step quenching process for high-magnesium-content aluminum alloy is characterized by comprising the following components of 6.0-9.9wt% of Mg, 1.1-3.01wt% of Zn, 0.1-1.15wt% of Si, at least one of Mn, cu, zr, sc, ti elements with the total content not exceeding 0.8wt%, and the balance of Al and unavoidable impurities, wherein the process comprises the following steps: (1) Preparing a novel high-magnesium-content aluminum alloy thermal deformation processing material by rolling or extrusion, and carrying out solution heating and heat preservation treatment at 460-545 ℃ for 30-150 min; (2) Carrying out first-stage quenching on the heat-deformed material heated by solid solution by adopting an air cooling mode, cooling to 420-450 ℃, wherein the cooling speed is 2-8 ℃ per second, and the transfer time from solid solution to first-stage quenching is not more than 15s; (3) Performing second-stage quenching on the heat-deformed machining material after the first-stage quenching is finished, and cooling to 180-230 ℃ at a cooling speed of 40-75 ℃ per second; (4) Carrying out third-stage quenching on the thermal deformation processed material after the second-stage quenching is finished, and cooling to 30-50 ℃ with the cooling speed of 2-8 ℃ per second; (5) And pre-deforming and aging the processed material after the step quenching.
  2. 2. The solid solution heating-step quenching process of a novel high-magnesium-content aluminum alloy according to claim 1, wherein the aluminum alloy is composed of at least one of 6.3-9.9wt% of Mg, 1.1-2.9wt% of Zn, 0.15-1.0wt% of Si, and Mn, cu, zr, sc, ti elements with the total content not exceeding 0.6wt%, and the balance of Al and unavoidable impurities.
  3. 3. The solid solution heating-step quenching process of a novel high-magnesium-content aluminum alloy according to claim 1 or 2, wherein in the step (1), the heat preservation temperature of the solid solution heating is 485-535 ℃, the heat preservation time is 60-120 min, and the heating rate of the heat distortion processing material from room temperature to the solid solution temperature is 15-20 ℃ per hour.
  4. 4. The solid solution heating-step quenching process of a novel high-magnesium-content aluminum alloy according to claim 1 or 2, wherein in the step (2), the final cooling temperature of the hot deformed material is 430-440 ℃, the wind speed is 40-60 m/s, the nozzle height is 50-80 mm, and the angle between the nozzle and the horizontal plane of the hot deformed material is 30-45 °.
  5. 5. The solution heating-step quenching process of a novel high-magnesium-content aluminum alloy according to claim 1 or 2, wherein in the step (3), in the second-stage quenching process, the final cooling temperature of the hot deformed material is 190-210 ℃, the pressure of a quenching medium is 4-7 bar up and down, the temperature of the quenching medium is 20-30 ℃, the height of a nozzle is 50-80 mm, and the horizontal angle between the nozzle and the hot deformed material is 30-40 ℃.
  6. 6. The solid solution heating-step quenching process of a novel high-magnesium-content aluminum alloy according to claim 1 or 2, wherein in the step (4), the final cooling temperature of the hot deformed material is 30-40 ℃, the wind speed is 40-60 m/s, the nozzle height is 50-80 mm, and the horizontal angle between the nozzle and the hot deformed material is 30-45 °.
  7. 7. The solid solution heating-step quenching process of the novel high-magnesium-content aluminum alloy according to claim 1 or 2, wherein in the step (3), the quenching medium is water-based quenching liquid in the second-stage quenching process, and the quenching medium comprises, by mass, 10% of polyglycol, 10% of butyl acrylate, 2% of styrene, 3% of acrylic acid, 5% of isomeric dodecanol, 0.3% of preservative, 0.1% of defoamer, 0.5% of antioxidant and the balance of water, wherein the preservative is nitrite, the defoamer is polyether modified silicon, and the antioxidant is tert-butylhydroquinone.
  8. 8. The solution heating-step quenching process of the novel high-magnesium-content aluminum alloy according to claim 1 or 2, wherein in the step (5), the pre-deformation amount of the heat-deformed material is 2-4.5%, the deformation rate is 0.5-1.0 mm/min, the dwell time is 50-100 s, and the time interval between the step quenching and the pre-deformation is not more than 5h.
  9. 9. The solid solution heating-step quenching process of a novel high-magnesium-content aluminum alloy according to claim 1 or 2, wherein in the step (5), the aging treatment of the heat-deformed material is two-stage artificial aging, the first stage is performed for 12-48 h aging at 60-105 ℃, the second stage is performed for 1-24 h aging at 135-190 ℃, and the time interval between the pre-deformation and the two-stage artificial aging is 5-60 days.
  10. 10. The solution heating-step quenching process for novel high magnesium content aluminum alloy according to claim 1 or 2, wherein in the step (4), after the third-stage quenching is finished, the heat distortion processed material does not generate quenching cracking, and the size of AlZnMg desolventized precipitated phase in the alloy matrix is not more than 350nm.
  11. 11. A novel high magnesium content aluminum alloy processing material, characterized in that the processing material is prepared by the process of any one of claims 1-10, and the quenching residual stress of the processing material is reduced by more than 50MPa compared with direct single-stage spray quenching.

Description

Solid solution heating-step quenching process for novel high-magnesium-content aluminum alloy Technical Field The invention relates to a quenching process of an aluminum alloy material, in particular to a novel solid solution heating-step quenching process of an aluminum alloy with high magnesium content. Background The aluminum alloy is widely applied to the fields of aerospace, transportation and the like by virtue of the characteristics of light specific gravity, high specific strength, easiness in processing, low cost, high cyclic utilization rate and the like. In order to meet the future development needs of high-end equipment in various fields, key components are required to be changed into light weight, high performance and low cost. Therefore, there is a need to further develop novel aluminum alloys having excellent comprehensive properties. Typical high-strength high-toughness aluminum alloy represented by an aluminum zinc magnesium (copper) system has specific strength of more than 150 MPa/g.cm 3 and good comprehensive performance matching, but the high zinc content and the high density are not beneficial to the light weight requirement. Of all commercial wrought aluminum alloys, the magnesium content was the highest, the density was the lowest, and the density was reduced by approximately 0.4% for every 1wt.% increase in magnesium content. Based on the method, a novel high-magnesium-content aluminum-magnesium-zinc alloy system is formed by reducing the zinc content in the aluminum-zinc-magnesium (copper) aluminum alloy and improving the magnesium content, and the aim of reducing the alloy density is fulfilled on the premise of ensuring the basic unchanged comprehensive performance. Unlike aluminum zinc magnesium (copper) alloys, the main precipitation-strengthening phase is the T Mg 32(Al,Zn)49 precipitate phase, rather than the η -MgZn 2 precipitate phase. Similar to aluminum zinc magnesium (copper) alloys, the novel high magnesium content aluminum magnesium zinc alloy system is also a higher alloyed alloy. In the solution quenching process, on one hand, when the quenching cooling speed is higher, the alloy material is easy to generate quenching cracking, the quenching residual stress is inevitably introduced in the quenching process, and the higher the quenching cooling speed is, the larger the quenching residual stress is, so that the subsequent cutting machining precision of the material is affected, and on the other hand, when the quenching cooling speed is reduced, the large-size T phase is separated and eluted in the quenching process, so that the comprehensive performances of the alloy material, such as strength, corrosiveness and the like, are affected. Disclosure of Invention The invention aims to provide a novel solid solution heating-stage quenching process for high-magnesium-content aluminum alloy, which ensures that an aluminum alloy processing material does not generate quenching cracking and reduces the size of a desolventized phase and the quenching residual stress. In order to achieve the above purpose, the present invention adopts the following technical scheme: A novel solid solution heating-step quenching process of high-magnesium-content aluminum alloy comprises the following components of at least one of elements Mn, cu, zr, sc, ti with the total content not exceeding 0.8wt%, namely 6.0-9.9wt% of Mg, 1.1-3.01wt% of Zn and 0.1-1.15wt% of Si, and the balance of Al and unavoidable impurities, wherein the process comprises the following steps: (1) Preparing a novel high-magnesium-content aluminum alloy thermal deformation processing material by rolling or extrusion, and carrying out solution heating and heat preservation treatment at 460-545 ℃ for 30-150 min; (2) Carrying out first-stage quenching on the heat-deformed material heated by solid solution by adopting an air cooling mode, cooling to 420-450 ℃, wherein the cooling speed is 2-8 ℃ per second, and the transfer time from solid solution to first-stage quenching is not more than 15s; (3) Performing second-stage quenching on the heat-deformed machining material after the first-stage quenching is finished, and cooling to 180-230 ℃ at a cooling speed of 40-75 ℃ per second; (4) Carrying out third-stage quenching on the thermal deformation processed material after the second-stage quenching is finished, and cooling to 30-50 ℃ with the cooling speed of 2-8 ℃ per second; (5) And pre-deforming and aging the processed material after the step quenching. Preferably, the aluminum alloy consists of at least one of Mg 6.3-9.9wt%, zn 1.1-2.9wt%, si 0.15-1.0wt% and Mn, cu, zr, sc, ti elements with the total content not exceeding 0.6wt%, and the balance of Al and unavoidable impurities. Preferably, in the step (1), the heat preservation temperature of the solid solution heating is 485-535 ℃, the heat preservation time is 60-120 min, and the heating rate of the thermal deformation processing material from room temperature to the solid solut