Heat treatment method and application of aluminum-based composite material

Abstract

The invention discloses a heat treatment method of an aluminum-based composite material and application of the heat treatment method, and relates to the technical field of aluminum alloy heat treatment processing. The method sequentially comprises the steps of first solid solution treatment, second solid solution treatment, quenching and primary aging treatment according to the process; the first solid solution is carried out under the condition of 505-515 DEG C; the second solid solution is carried out under the condition of 525-535 DEG C; the aging treatment is carried out under the condition of 150 to 170 DEG C; the quenching is carried out in clear water with the temperature of 50-80 DEG C; by adjusting solid solution and aging treatment, the purpose of improving the comprehensive mechanical property of the material under the action of an alloy strengthening phase is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of aluminum alloy heat treatment processing, in particular to a heat treatment method for aluminum-based composite materials and application thereof. Background Art

[0002] Al-Cu alloys are widely used in aviation, aerospace, and machinery due to their excellent casting properties and superior mechanical properties after heat treatment. With new product requirements for high corrosion resistance, strength, modulus, and elongation, the limitations of conventional Al-Cu alloy design have made it impossible to significantly improve their overall performance. Therefore, strengthening elements such as Mg, Mn, Ag, and Ti are added to this Al-Cu cast aluminum alloy solution. Chemical reactions occur at high temperatures, and by controlling the composition of the various alloying elements, an alloy-reinforced phase forms within the aluminum matrix, ultimately forming an alloy-reinforced aluminum-matrix composite. The presence of the alloy-reinforced phase in the matrix improves the overall mechanical properties of the material. However, compared to conventional Al-Cu alloys, these aluminum-matrix composites contain a large amount of alloy-reinforced phase. This slows the dissolution of the alloying elements into the matrix during solution treatment, making full decomposition and homogenization of the composition and structure more difficult than for aluminum alloys without alloy-reinforced phases. Furthermore, during aging treatment, the large amount of alloy-reinforced phases slows precipitation and significantly reduces the elongation of the material compared to the original matrix. The matrix material is a strengthenable aluminum alloy with mature and stable solution aging process parameters. The process parameters of the matrix material were used in the initial trial production of aluminum-based composite materials. The test results showed that the mechanical properties of the material did not meet the design requirements. Summary of the Invention

[0003] The purpose of the present invention is to provide a heat treatment method for aluminum-based composite materials and its application, which can improve the comprehensive mechanical properties of the material under the action of the alloy strengthening phase by adjusting the solid solution and aging treatment.

[0004] In order to achieve the above object, the present invention adopts the following technical means: A heat treatment method for an aluminum-based composite material, comprising, in sequence, a first solid solution treatment, a second solid solution treatment, a quenching treatment, and an aging treatment; The first solid solution is carried out at 505-515°C; The second solid solution is carried out at 525-535°C; The aging treatment is carried out at 150-170°C; The quenching is carried out in clean water at 50-80°C.

[0005] Preferably, the first solution heat preservation time is 6 to 12 hours, and the second solution heat preservation time is 8 to 14 hours.

[0006] Furthermore, the heating rate of the first solid solution does not exceed 100°C / h, and the charging temperature of the first solid solution does not exceed 200°C.

[0007] Furthermore, after the second solid solution is completed, the process is transferred to the quenching process within 15 seconds.

[0008] Furthermore, the charging temperature of the aging treatment does not exceed 80°C, and the heating rate does not exceed 100°C / h.

[0009] Furthermore, the invention relates to an aluminum-based composite material of the Al-Cu system doped with strengthening elements including Mg, Mn, Ag and Ti.

[0010] An application of the aforementioned heat treatment method for aluminum-based composite materials in the preparation of aluminum-based composite materials.

[0011] During use, the present invention has the following beneficial effects: Through a two-stage solution treatment, the eutectic is fully dissolved in the first solution, and then the alloying elements and strengthening phases are fully integrated into the aluminum body during the second solution. Combined with rapid quenching, the decomposition of the solid solution during the transfer process is avoided, the degree of supercooling is increased, and a supersaturated solid solution is obtained to the maximum extent, thus preparing the organization for subsequent aging treatment.

[0012] In addition, the aging treatment of the present application is used to control the dispersion of the matrix precipitation phase after the first solid solution and the second solid solution, the size of the grain boundary precipitation phase and the width of the intergranular precipitation-free phase, and adjust the structure, size and distribution of the precipitation phase to obtain good mechanical properties.

[0013] Therefore, under the heat treatment process involved in the present invention, the composite aluminum alloy with second phase solid solution and dispersion strengthening in the matrix can obtain good mechanical properties, and while the corrosion resistance of the matrix is ​​improved, it can also have good mechanical properties.

[0014] Moreover, the aluminum-based alloy processed by this process can pass the large pear load-bearing test even when it is used to prepare cylinders, thin walls or asymmetric structures with different inner cavity distributions. DETAILED DESCRIPTION

[0015] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments.

[0016] Therefore, the following detailed description of the embodiments of the present invention is not intended to limit the scope of the claimed invention, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort are also within the scope of protection of the present invention.

[0017] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments of the present invention can be combined with each other.

[0018] A heat treatment method for an aluminum-based composite material, comprising, in sequence, a first solid solution treatment, a second solid solution treatment, a quenching treatment, and an aging treatment; The first solid solution is carried out at a temperature of 505-515° C., and the second solid solution is carried out after the eutectic is fully dissolved.

[0019] The second solid solution is carried out at 525-535° C. to ensure that the alloy elements and the strengthening phase are fully dissolved into the aluminum matrix.

[0020] The aging treatment is carried out at 150-170° C., thereby effectively controlling the dispersion of the matrix precipitated phase, the size of the grain boundary precipitated phase, and the width of the intergranular precipitated phase-free phase, and effectively adjusting the structure, size, and distribution of the entire precipitated phase, thereby obtaining good mechanical properties.

[0021] The quenching is carried out in clean water at 50-80°C.

[0022] In this way, a two-stage solid solution and a single-stage aging treatment are adopted. During the two-stage solid solution, the alloy elements and strengthening phases are ensured to be fully integrated into the aluminum matrix under the premise of ensuring that the material is not overheated or overburned. Then, the material is quickly transferred to clean water for quenching to obtain a supersaturated solid solution. Then, through aging treatment, the dispersed strengthening phase is precipitated, thereby improving the matrix performance.

[0023] The first solution heat preservation time is 6 to 12 hours, and the second solution heat preservation time is 8 to 14 hours.

[0024] The heating rate of the first solid solution does not exceed 100°C / h, and the furnace charging temperature of the first solid solution does not exceed 200°C.

[0025] This ensures that the effects of thermal stress inside the material are reduced.

[0026] After the second solid solution is completed, the process is transferred to the quenching step within 15 seconds.

[0027] This effectively avoids decomposition of the solid solution during the transfer process after the first solid solution treatment and the second solid solution treatment.

[0028] The charging temperature of the aging treatment does not exceed 80° C., the heating rate does not exceed 100° C. / h, and the aging treatment is maintained for 3 to 12 hours and then air-cooled.

[0029] Furthermore, by controlling the dispersion of the matrix precipitated phase, the size of the grain boundary precipitated phase and the width of the intergranular precipitate-free phase through aging, the structure, size and distribution of the precipitated phase are adjusted to obtain good comprehensive mechanical properties.

[0030] In addition, the aforementioned heat treatment method for aluminum-based composite materials is applied in the preparation of aluminum-based composite materials that are Al-Cu based and doped with strengthening elements including Mg, Mn, Ag, and Ti.

[0031] The present invention will be further explained below in conjunction with specific implementation processes.

[0032] Example 1 S1. During the solid solution, the present invention sets the furnace temperature to ≤200°C and controls the heating rate to ≤100°C / h according to the alloying characteristics of aluminum-based composite materials to reduce the influence of thermal stress. The temperature is heated to 505-515°C and maintained for 6-12 hours to carry out the first solid solution. After the eutectic is fully dissolved, the temperature is increased to 525-535°C and maintained for 8-14 hours to carry out the second solid solution. The alloying elements and strengthening phases are fully dissolved into the aluminum matrix. After the second solid solution is completed, the solid is quickly transferred to 5-80°C clean water for quenching and cooling within 15 seconds to avoid decomposition of the solid solution during the transfer process, increase the degree of supercooling, and obtain a supersaturated solid solution to the maximum extent, thereby making good organizational preparation for subsequent aging strengthening.

[0033] S2. During aging, the present invention maintains a furnace charge temperature of ≤80°C, a controlled heating rate of ≤100°C / h, and slowly heats to a temperature between 150°C and 170°C, maintaining the temperature for 3 to 12 hours, followed by air cooling. By controlling the dispersion of matrix precipitates, the size of grain boundary precipitates, and the width of intergranular free precipitates during aging, the structure, size, and distribution of the precipitates are adjusted to achieve excellent overall mechanical properties.

[0034] Comparative Example 1 S1. During solution, according to the alloying characteristics of aluminum-based composite materials, the charging temperature is ≤200℃, and the heating rate is controlled to ≤100℃ / h to reduce the influence of thermal stress. Heat to 525~535℃, maintain for 8~14 hours, and quickly transfer to 5~80℃ clean water for quenching and cooling within 15 seconds.

[0035] S2. During aging, the charging temperature of the present invention is ≤80°C, the heating rate is controlled to ≤100°C / h, and the steel is slowly heated to between 150 and 170°C and maintained for 3 to 12 hours for aging, followed by air cooling.

[0036] Comparative Example 2 S1. During solution treatment, keep the furnace temperature ≤ 200°C and the heating rate ≤ 100°C / h. Heat to 490-500°C and maintain for 6-12 hours for the first solution treatment. Then raise the temperature to 525-535°C and maintain for 8-14 hours for the second solution treatment. After the second solution treatment, quickly transfer the steel to 5-80°C water for quenching within 15 seconds.

[0037] S2. During aging, the charging temperature of the furnace should be ≤80℃, and the heating rate should be controlled to ≤100℃ / h. Slowly heat to 150~170℃ and maintain for 3~12 hours for aging, then air cool.

[0038] Comparative Example 3 S1. During solution treatment, the furnace temperature should be ≤200°C, and the heating rate should be controlled at ≤100°C / h. Heat to 505-515°C and maintain for 6-12 hours for the first solution treatment. Then, increase the temperature to 518-520°C and maintain for 8-14 hours for the second solution treatment. After the second solution treatment, quickly transfer the sample to 5-80°C clean water for quenching and cooling within 15 seconds.

[0039] S2. During aging, the charging temperature of the furnace should be ≤80℃, and the heating rate should be controlled to ≤100℃ / h. Slowly heat to 150~170℃ and maintain for 3~12 hours for aging, then air cool.

[0040] Comparative Example 4 S1. During solution treatment, the furnace temperature should be ≤200°C, and the heating rate should be controlled at ≤100°C / h. Heat to 505-515°C and maintain for 6-12 hours for the first solution treatment. Then, increase the temperature to 540-550°C and maintain for 8-14 hours for the second solution treatment. After the second solution treatment, quickly transfer the sample to 5-80°C water for quenching within 15 seconds.

[0041] S2. During aging, the charging temperature of the furnace should be ≤80℃, and the heating rate should be controlled to ≤100℃ / h. Slowly heat to 150~170℃ and maintain for 3~12 hours for aging, then air cool.

[0042] By observing the mechanical properties of the aluminum-based composite materials after heat treatment in the above-mentioned Example 1 and Comparative Example 1, it can be clearly seen that Example 1 has the best mechanical properties.

[0043] Specifically, Example 1 is compared with Comparative Example 1. Since Comparative Example 1 adopts a single-stage solid solution, the process of alloy elements being integrated into the matrix is ​​slow and difficult during the solid solution process, and the decomposition and homogenization between the components and structures are poor. Therefore, the mechanical properties of the single-stage solid solution are reduced compared to the two-stage solid solution method.

[0044] Compared with Example 2, Example 1 has a lower temperature during the first solid solution reaction, and thus cannot achieve the effect of the first solid solution reaction. Therefore, the mechanical properties of Example 2 are closer to those of Example 1, and both are worse than those of Example 1.

[0045] Compared to Comparative Example 3, while the first solid solution treatment in Example 1 was effective, the material properties were relatively sensitive to temperature due to the proximity to the melting point of the matrix material. During the second solid solution treatment, the lower treatment temperature hindered the matrix material from migrating the eutectic, hindering the full and uniform dissolution of alloying elements and strengthening phases into the aluminum matrix. Consequently, the mechanical properties of Comparative Example 3 were somewhat reduced compared to Example 1.

[0046] Compared with Example 4, Example 1 also refers to the above. Since the second solid solution temperature is too high and closer to the melting point of the material itself, the matrix material has too low an obstacle to the migration of the eutectic, which easily causes a large amount of alloy elements and strengthening phases to gather at a certain point, which is not conducive to their uniform dissolution into the aluminum matrix. Therefore, the mechanical properties of Example 4 are also inferior to those of Example 1.

[0047] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A heat treatment method for an aluminum-based composite material, characterized in that: The process includes the first solid solution, the second solid solution, quenching and the first aging treatment; The first solid solution is carried out at 505-515°C; The second solid solution is carried out at 525-535°C; The aging treatment is carried out at 150-170°C; The quenching is carried out in clean water at 50-80°C.

2. The heat treatment method of an aluminum-based composite material according to claim 1, characterized in that: The first solution heat preservation time is 6 to 12 hours, and the second solution heat preservation time is 8 to 14 hours.

3. The heat treatment method of an aluminum-based composite material according to claim 1, characterized in that: The heating rate of the first solid solution does not exceed 100°C / h, and the furnace charging temperature of the first solid solution does not exceed 200°C.

4. The heat treatment method of an aluminum-based composite material according to claim 1, characterized in that: After the second solid solution is completed, the process is transferred to the quenching process within 15 seconds.

5. The heat treatment method of an aluminum-based composite material according to claim 1, characterized in that: The furnace temperature for the aging treatment does not exceed 80°C, and the heating rate does not exceed 100°C / h.

6. The heat treatment method of an aluminum-based composite material according to claim 1, characterized in that: Aluminum-based composite materials based on the Al-Cu system and doped with strengthening elements including Mg, Mn, Ag, and Ti.

7. Use of the heat treatment method of the aluminum-based composite material according to any one of claims 1 to 6 in the preparation of the aluminum-based composite material.