CN-122013000-A - Superfine crystal aluminum magnesium alloy and preparation method and application thereof

Abstract

The invention relates to an ultrafine grain aluminum magnesium alloy and a preparation method and application thereof, and the ultrafine grain aluminum magnesium alloy comprises the chemical components of 4.0-6.0 wt% of Mg element and the balance of Al and unavoidable impurities, wherein the grain size of the aluminum magnesium alloy is 100-1000 nm, and a grain boundary of the aluminum magnesium alloy is provided with a grain boundary segregation network of Mg element. According to the superfine aluminum-magnesium alloy provided by the invention, the strength of the aluminum alloy is ensured, the grain boundary structure is accurately regulated and controlled through low-temperature aging treatment, the Mg element is induced to undergo segregation in the grain boundary region, a stable three-dimensional discontinuous grain boundary segregation network is constructed, the grain boundary segregation network can effectively reduce the grain boundary energy and inhibit the growth of grains, and therefore, the tissue thermal stability of the superfine aluminum alloy is obviously improved.

Inventors

• FENG MAN
• LI LEI
• ZHOU ZHONGCHEN
• HAN HONGYONG
• LI ZIFU
• LIU XINGDI
• QI LELE
• PAI JUNJUN
• Ai Caijiao

Assignees

• 滨州魏桥国科高等技术研究院
• 山东宏桥新型材料有限公司
• 魏桥国科(深圳)科学工程技术研究有限公司

Dates

Publication Date

20260512

Application Date

20260123

Claims (10)

1. 1. The superfine crystal aluminum-magnesium alloy is characterized by comprising the chemical components of 4.0-6.0 wt% of Mg element and the balance of Al and unavoidable impurities; The grain size of the aluminum magnesium alloy is 100-1000 nm; And Mg element grain boundary segregation network is arranged at the grain boundary of the aluminum magnesium alloy.
2. 2. A method for preparing the superfine crystal aluminum-magnesium alloy according to claim 1, which is characterized by comprising the following steps of preparing an as-cast aluminum-magnesium alloy according to the mass percentage of Mg element of 4.0-6.0 wt%, and carrying out solution treatment and severe plastic deformation treatment on the as-cast aluminum-magnesium alloy to obtain the superfine crystal aluminum-magnesium alloy.
3. 3. The method according to claim 2, wherein the solution treatment temperature is 400-450 ℃.
4. 4. A method of manufacture according to claim 3, wherein the solution treatment is carried out for a treatment time of 18-24 h.
5. 5. The method according to any one of claims 2 to 4, further comprising the step of water quenching the alloy to room temperature after the solution treatment.
6. 6. The production method according to claim 2, wherein the treatment method of the severe plastic deformation treatment comprises any one of a high-pressure torsion method, an equal-diameter angular extrusion method, and a multidirectional free forging method.
7. 7. The method according to claim 6, wherein the deformation temperature is not higher than 100 ℃ during the severe plastic deformation treatment, and the final grain size is refined to 100-1000 nm.
8. 8. The method according to claim 2, wherein the aging treatment is carried out at a treatment temperature of 100-150 ℃.
9. 9. The method according to claim 8, wherein the aging treatment is carried out for a treatment time of 5 to 10 h.
10. 10. Use of the ultrafine grained aluminum-magnesium alloy according to claim 1 or the aluminum-magnesium alloy produced by the production method according to any one of claims 2 to 9 in an environment with a temperature of 200 ℃ or more.

Description

Superfine crystal aluminum magnesium alloy and preparation method and application thereof Technical Field The invention relates to the technical field of aluminum alloy processing, in particular to an ultrafine grain aluminum magnesium alloy and a preparation method and application thereof. Background Aluminum alloy is used as a typical light metal structural material, and is widely applied to the fields of aerospace, automobile manufacturing, electronic communication and the like due to excellent specific strength, corrosion resistance, processability and good connection performance. With the rapid development of high-end manufacturing industry, higher requirements are put forward on the aspects of strength, light weight, thermal stability and the like of aluminum alloy, and the development of novel high-performance aluminum alloy materials has become a key subject in material science. In recent years, ultra-fine grain (grain size of 100-1000 nm) materials are receiving extensive attention and becoming an important research direction in the field of metal structural materials because of their remarkable advantages over traditional coarse grain materials in terms of strength, hardness, fatigue properties and the like. Severe plastic deformation has become a core means for preparing bulk ultrafine grained metallic materials due to its excellent grain refining ability. While the severe plastic deformation process can effectively improve the strength of the material, the simultaneous introduction of a large number of high-density defects (such as dislocations, vacancies, and grain boundaries) significantly reduces the thermal stability of the material. Research shows that the ultra-fine grain metal can maintain a relatively stable tissue structure below half of the melting point (0.5T m), but aluminum and aluminum alloys have low melting points, and the ultra-fine grain structure is easy to coarsen crystal grains and destabilize in tissue at a low temperature (more than or equal to 200 ℃), so that the performance is rapidly degraded, and the stability and the reliability of engineering application are severely limited. Therefore, the method for improving the structure stability of the superfine aluminum alloy in the high-temperature environment and inhibiting the growth of crystal grains and the evolution of defects is a key technical problem which is needed to be broken through in the field at present, and is also a core problem which is focused and solved by the method. Disclosure of Invention The invention provides an ultrafine grain aluminum-magnesium alloy and a preparation method and application thereof, which are used for solving the problem of poor tissue stability of the existing ultrafine grain aluminum alloy under the high-temperature condition. In a first aspect, the invention provides an ultrafine grain aluminum-magnesium alloy, which comprises the chemical components of 4.0-6.0 wt% of Mg element and the balance of Al and unavoidable impurities; The grain size of the aluminum magnesium alloy is 100-1000 nm; And Mg element grain boundary segregation network is arranged at the grain boundary of the aluminum magnesium alloy. The second aspect of the invention provides a preparation method of the superfine aluminum magnesium alloy, which comprises the following steps of preparing an as-cast aluminum magnesium alloy according to the mass percentage of Mg element of 4.0-6.0 wt percent, and carrying out solution treatment and severe plastic deformation treatment on the as-cast aluminum magnesium alloy to obtain the superfine aluminum magnesium alloy. In an alternative embodiment, the solution temperature of the solution treatment is 400-450 ℃. In an alternative embodiment, the solution time of the solution treatment is from 18 to 24 h. In an alternative embodiment, the solution treatment further comprises the step of water quenching the alloy to room temperature. In an alternative embodiment, the method of treating the severe plastic deformation includes any one of high-pressure torsion, constant-diameter angular extrusion, and multidirectional free forging. In an alternative embodiment, the deformation temperature is not higher than 100 ℃ during the severe plastic deformation treatment, and the final grain size is refined to 100-1000 nm. In an alternative embodiment, the aging treatment is at a treatment temperature of 100-150 ℃. In an alternative embodiment, the aging treatment has a treatment time of 5 to 10 h. In a second aspect, the invention also provides an application of the ultrafine grain aluminum magnesium alloy or the aluminum magnesium alloy prepared by the preparation method in an environment with the temperature of more than or equal to 200 ℃. The technical scheme of the invention has the following advantages: 1. The superfine crystal aluminum-magnesium alloy comprises the chemical components of 4.0-6.0 wt% of Mg element and the balance of Al and unavoidable impurities, wherein the grain s