Method for enhancing strength and plasticity of aluminum alloy

Abstract

The invention relates to the technical field of aluminum alloys, in particular to a method for enhancing the strength and plasticity of an aluminum alloy, which comprises the following steps: carrying out ultrasonic vibration and high-pressure co-treatment on the aluminum alloy to separate out a precipitation strengthening phase in the aluminum alloy and uniformly distribute the precipitation strengthening phase. According to the method, ultrasonic vibration and high-pressure treatment modes are combined, and the microstructure morphology and precipitate distribution of the aluminum alloy are promoted by utilizing the precipitation strengthening characteristic in the aluminum alloy strengthening process, so that the comprehensive performance of the aluminum alloy is improved; the yield strength and the tensile strength are remarkably improved while the elongation of the aluminum alloy is kept basically free of loss, and the problem of contradiction between the strength and the plasticity of the material is effectively solved; compared with the traditional heat treatment method, the method disclosed by the invention can be carried out at room temperature, reduces the aging heat treatment link, reduces the emission of harmful substances, is more energy-saving and environment-friendly, is simple and feasible in treatment process, has higher economical efficiency and industrial application prospect, and lays an important foundation for the application of the production process.

Description

Technical Field

[0001] The invention relates to the technical field of aluminum alloys, and in particular to a method for enhancing the strength and plasticity of aluminum alloys. Background Art

[0002] Aluminum alloy is a widely used lightweight material with advantages such as high specific strength, good electrical conductivity, excellent corrosion resistance and low density. However, in recent years, with the increasing demand for lightweighting in industries such as automobiles and aircraft, the insufficient strength of aluminum alloy has limited its wider application.

[0003] Traditional aluminum alloys are strengthened by adjusting the alloy composition and controlling the heat treatment process. Studies have shown that adding rare metals is beneficial to improving the strength of the alloy, but it is costly and may bring toxicity and environmental risks. In addition, second-phase precipitation strengthening is an effective way to improve the strength of aluminum alloys during heat treatment. It improves the strength by precipitating fine precipitation strengthening phases from the aluminum alloy matrix. However, due to factors such as chemical composition and heat treatment, the precipitation strengthening phases are often unevenly distributed, large in size, and of varying shapes, resulting in unsatisfactory strengthening effects. In addition, the heat treatment process requires precise control, and actual production is difficult, all of which limit the wider application of aluminum alloys.

[0004] In view of this, the present invention is proposed. Summary of the invention

[0005] The purpose of the present invention is to provide a method for enhancing the strength and plasticity of aluminum alloys. The method combines ultrasonic vibration and high pressure treatment, utilizes the precipitation strengthening characteristics in the aluminum alloy strengthening process, promotes its microstructure morphology and the distribution of precipitates, so as to achieve the improvement of the comprehensive performance of the aluminum alloy.

[0006] The first aspect of the present invention provides a method for enhancing the strength and plasticity of aluminum alloy, comprising the following steps: treating the aluminum alloy with ultrasonic vibration and high pressure to precipitate and evenly distribute the precipitation strengthening phase in the aluminum alloy.

[0007] As a preferred embodiment of this technical solution, the following steps are included:

[0008] S1. Place the aluminum alloy under the connecting rod of the ultrasonic vibration output device, turn on the power of the ultrasonic vibration output device, and output ultrasonic vibration;

[0009] S2. Turn on the pressure transmission device to apply high pressure to the aluminum alloy so that the precipitation strengthening phase in the aluminum alloy is precipitated and evenly distributed.

[0010] As a preferred embodiment of the present technical solution, the frequency of the ultrasonic vibration is controlled at 10-100 kHz, and the treatment time of the ultrasonic vibration is 5-60 minutes.

[0011] As a preferred embodiment of the present technical solution, the frequency of the ultrasonic vibration is 20 kHz, and the treatment time of the ultrasonic vibration is 10-20 minutes.

[0012] As a preferred embodiment of the present technical solution, the high pressure is controlled at 50-500 MPa, and the high pressure treatment time is 5-60 minutes.

[0013] As a preferred embodiment of the present technical solution, the high pressure is 250 MPa, and the high pressure treatment time is 10-20 minutes.

[0014] As a preferred embodiment of the present technical solution, the aluminum alloy adopts T4 state of aluminum alloy 2024, and the main elements are aluminum, copper and magnesium.

[0015] As a preferred embodiment of the present technical solution, the percentages of main constituent elements of the aluminum alloy include: Cu: 3.8-4.9%, Mg: 1.2-1.8%, Mn: 0.3-0.9%, Fe≤0.5%, and Al as the balance.

[0016] As a preferred embodiment of the present technical solution, the aluminum alloy is in a block shape.

[0017] A second aspect of the present invention provides an aluminum alloy prepared by the above-mentioned method for enhancing the strength and plasticity of aluminum alloy.

[0018] A third aspect of the present invention provides an application of an aluminum alloy, wherein the aluminum alloy is applied to fields such as aerospace and automobile manufacturing.

[0019] The present invention has the following beneficial effects:

[0020] (1) The method of the present invention combines ultrasonic vibration and high pressure treatment to utilize the precipitation strengthening characteristics during the aluminum alloy strengthening process to promote its microstructure morphology and the distribution of precipitates, thereby achieving an improvement in the comprehensive performance of the aluminum alloy;

[0021] (2) The method of the present invention significantly improves the yield strength and tensile strength while maintaining the aluminum alloy's elongation substantially without loss, thus effectively resolving the contradiction between material strength and plasticity;

[0022] (3) Compared with the traditional heat treatment method, the method of the present invention can be carried out at room temperature, which reduces the aging heat treatment step, reduces the emission of harmful substances, is more energy-saving and environmentally friendly, and has a simple and easy treatment process. It has high economic efficiency and industrial application prospects, laying an important foundation for its production process application. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 This is a schematic structural diagram of the high-pressure ultrasonic vibration processing system provided by the present invention.

[0025] Figure 2 The stress-strain curves after high-pressure ultrasonic vibration treatment for different time periods provided by the present invention.

[0026] Figure 3 This is a morphological diagram of the distribution of precipitates before and after high-pressure ultrasonic vibration treatment provided by the present invention. DETAILED DESCRIPTION

[0027] It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0028] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form also includes the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0029] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] Example 1

[0031] This embodiment provides a method for enhancing the strength and plasticity of aluminum alloy, comprising the following steps:

[0032] (1) Sample preparation

[0033] The aluminum alloy 2024 sample treated in T4 state was prepared into a block, and its main chemical composition was: Cu: 3.8-4.9%, Mg: 1.2-1.8%, Mn: 0.3-0.9%, Fe≤0.5%, and Al as the balance.

[0034] T4 state treatment includes natural aging after solid solution treatment to ensure that the aluminum alloy has suitable processing strength and create conditions for subsequent ultrasonic vibration and high pressure coordinated treatment.

[0035] (2) Equipment configuration of high-pressure ultrasonic vibration treatment system

[0036] like Figure 1 As shown, at room temperature, aluminum alloy 2024 is placed under the connecting rod of the high-pressure ultrasonic vibration treatment system. The high-pressure ultrasonic vibration treatment system consists of an outer frame and an ultrasonic vibration treatment system. The ultrasonic vibration treatment system is placed in the outer frame. The ultrasonic vibration treatment system consists of a piezoelectric ultrasonic vibration outputter and a connecting rod. The ultrasonic vibration outputter is driven and controlled by a power supply. The outer frame is connected to a pressure transmission device to apply high pressure.

[0037] (3) Processing

[0038] By turning on the power of the ultrasonic vibration output device, the ultrasonic vibration output device can output ultrasonic vibration to the end of the connecting rod. In this embodiment, the frequency of the ultrasonic vibration used is 20 kHz.

[0039] At the same time, the pressure transmission device is turned on to apply high pressure to the aluminum alloy. In this embodiment, a high pressure of 250 MPa is used.

[0040] In this embodiment, the high pressure ultrasonic vibration treatment time is 10 minutes, and the effect after treatment is as follows: Figure 2 As shown in the figure, it can be seen that the yield strength and tensile strength of the treated T4 state aluminum alloy 2024 are increased by 43% and 18.49% respectively, and the elongation is basically not lost.

[0041] like Figure 3 As shown, this embodiment also provides an aluminum alloy, which is prepared by the method of enhancing the strength and plasticity of the aluminum alloy of this embodiment. It can be seen from the figure that by combining high-pressure ultrasonic vibration treatment and utilizing the precipitation strengthening characteristics in the aluminum alloy strengthening process, the precipitation strengthening phase in the aluminum alloy is promoted, and the precipitate increases significantly and is more evenly distributed, thereby synergistically improving the strength and plasticity of the aluminum alloy.

[0042] Example 2

[0043] This embodiment is basically the same as embodiment 1, except that: in this embodiment, the high-pressure ultrasonic vibration treatment time is 15 minutes, and the effect after treatment is as follows: Figure 2 As shown in the figure, it can be seen that the yield strength and tensile strength of the treated T4 aluminum alloy 2024 are increased by 58% and 25.27%, and the elongation is basically not lost.

[0044] Example 3

[0045] This embodiment is basically the same as embodiment 1, except that: in this embodiment, the high-pressure ultrasonic vibration treatment time is 20 minutes, and the effect after treatment is as follows: Figure 2 As shown in the figure, it can be seen that the yield strength and tensile strength of the treated T4 state aluminum alloy 2024 are increased by 49.6% and 21.81%, and the elongation is basically not lost.

[0046] Example 4

[0047] This embodiment is basically the same as Embodiment 1, except that: in this embodiment, the treatment time of high-pressure ultrasonic vibration is 30 minutes.

[0048] Example 5

[0049] This embodiment is basically the same as Embodiment 1, except that: in this embodiment, the treatment time of high-pressure ultrasonic vibration is 40 minutes.

[0050] Example 6

[0051] This embodiment is basically the same as Embodiment 1, except that: in this embodiment, the treatment time of high-pressure ultrasonic vibration is 50 minutes.

[0052] Example 7

[0053] This embodiment is basically the same as Embodiment 1, except that: in this embodiment, the treatment time of high-pressure ultrasonic vibration is 60 minutes.

[0054] Example 8

[0055] This embodiment is basically the same as Embodiment 1, except that in this embodiment, the frequency of ultrasonic vibration used is 10 kHz.

[0056] Example 9

[0057] This embodiment is basically the same as Embodiment 1, except that in this embodiment, the frequency of ultrasonic vibration used is 40 kHz.

[0058] Example 10

[0059] This embodiment is basically the same as Embodiment 1, except that in this embodiment, the frequency of ultrasonic vibration used is 60 kHz.

[0060] Embodiment 11

[0061] This embodiment is basically the same as Embodiment 1, except that in this embodiment, the frequency of ultrasonic vibration used is 80 kHz.

[0062] Example 12

[0063] This embodiment is basically the same as Embodiment 1, except that in this embodiment, the frequency of ultrasonic vibration used is 100 kHz.

[0064] Example 13

[0065] This embodiment is basically the same as Embodiment 1, except that in this embodiment, a high pressure of 50 MPa is used.

[0066] Embodiment 14

[0067] This embodiment is basically the same as Embodiment 1, except that in this embodiment, a high pressure of 100 MPa is used.

[0068] Embodiment 15

[0069] This embodiment is basically the same as Embodiment 1, except that in this embodiment, a high pressure of 200 MPa is used.

[0070] Example 16

[0071] This embodiment is basically the same as Embodiment 1, except that in this embodiment, a high pressure of 300 MPa is used.

[0072] Embodiment 17

[0073] This embodiment is basically the same as Embodiment 1, except that in this embodiment, a high pressure of 400 MPa is used.

[0074] Embodiment 18

[0075] This embodiment is basically the same as Embodiment 1, except that in this embodiment, a high pressure of 500 MPa is used.

[0076] The distribution morphology, yield strength, tensile strength and elongation of the aluminum alloy precipitates after treatment in Examples 4-18 are basically consistent with those in Example 1 and will not be presented in detail here.

[0077] Comparative Example 1

[0078] This comparative example is basically the same as Example 1, except that in this comparative example, the treatment time of high-pressure ultrasonic vibration is 5 minutes.

[0079] After the treatment in this comparative example, the aluminum alloy has insufficient improvement in strength and plasticity due to insufficient treatment time of high-pressure ultrasonic vibration.

[0080] Comparative Example 2

[0081] This comparative example is basically the same as Example 1, except that in this comparative example, the treatment time of high-pressure ultrasonic vibration is 60 minutes.

[0082] In this comparative example, the high-pressure ultrasonic vibration treatment time of the aluminum alloy after treatment is too long, which will lead to a decrease in strength and plasticity.

[0083] Comparative Example 3

[0084] This comparative example is basically the same as Example 1, except that in this comparative example, a high pressure of 30 MPa is used.

[0085] The elongation of the aluminum alloy after treatment in this comparative example is lower than that of the original state.

[0086] Comparative Example 4

[0087] This comparative example is basically the same as Example 1, except that in this comparative example, the cast aluminum alloy 2024 sample is prepared into a block.

[0088] After treatment in this comparative example, the strength and plasticity of aluminum alloy 2024 are also improved to a certain extent, but the overall strength does not reach the strength of T4 aluminum alloy.

[0089] Comparative Example 5

[0090] This comparative example is basically the same as Example 1, except that in this comparative example, the aluminum alloy 6061 sample is prepared into a block, and after ultrasonic treatment, the strengthening effect is not obvious.

[0091] In summary, the method of the present invention combines ultrasonic vibration and high-pressure treatment methods, utilizes the precipitation strengthening characteristics in the aluminum alloy strengthening process, promotes its microstructure morphology and the distribution of precipitates, so as to achieve the improvement of the comprehensive performance of the aluminum alloy; the method of the present invention significantly improves the yield strength and tensile strength while maintaining the aluminum alloy elongation basically without loss, and effectively solves the contradiction between material strength and plasticity; compared with traditional heat treatment methods, the method of the present invention can be carried out at room temperature, reduces the aging heat treatment link, reduces the emission of harmful substances, is more energy-saving and environmentally friendly, and the treatment process is simple and easy, with high economy and industrial application prospects, laying an important foundation for its production process application.

[0092] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for enhancing the strength and plasticity of aluminum alloy, characterized in that: The method comprises the following steps: performing ultrasonic vibration and high pressure coordinated treatment on the aluminum alloy so that the precipitation strengthening phase in the aluminum alloy is precipitated and evenly distributed.

2. The method for enhancing the strength and plasticity of aluminum alloy according to claim 1, characterized in that: The steps include: S1. Place the aluminum alloy under the connecting rod of the ultrasonic vibration output device, turn on the power of the ultrasonic vibration output device, and output ultrasonic vibration; S2. Turn on the pressure transmission device to apply high pressure to the aluminum alloy so that the precipitation strengthening phase in the aluminum alloy is precipitated and evenly distributed.

3. The method for enhancing the strength and plasticity of aluminum alloy according to claim 1, characterized in that: The frequency of the ultrasonic vibration is controlled at 10-100 kHz, and the treatment time of the ultrasonic vibration is 5-60 minutes.

4. The method for enhancing the strength and plasticity of aluminum alloy according to claim 3, characterized in that: The frequency of the ultrasonic vibration is 20 kHz, and the treatment time of the ultrasonic vibration is 10-20 minutes.

5. The method for enhancing the strength and plasticity of aluminum alloy according to claim 1, characterized in that: The high pressure is controlled at 50-500 MPa, and the high pressure treatment time is 5-60 minutes.

6. The method for enhancing the strength and plasticity of aluminum alloy according to claim 5, characterized in that: The high pressure is 250 MPa, and the high pressure treatment time is 10-20 minutes.

7. The method for enhancing the strength and plasticity of aluminum alloy according to claim 1, characterized in that: The aluminum alloy adopts the T4 state of aluminum alloy 2024.

8. The method for enhancing the strength and plasticity of aluminum alloy according to claim 1, characterized in that: The percentages of main constituent elements of the aluminum alloy include: Cu: 3.8-4.9%, Mg: 1.2-1.8%, Mn: 0.3-0.9%, Fe≤0.5%, and Al as the balance.

9. The method for enhancing the strength and plasticity of aluminum alloy according to claim 1, characterized in that: The aluminum alloy is in block shape.

10. An aluminum alloy, characterized in that: The aluminum alloy is prepared by the method for enhancing the strength and plasticity of aluminum alloy as described in any one of claims 1 to 9.

Images