High-strength aluminum alloy building material for curtain walls of doors and windows and preparation method thereof

Abstract

The application belongs to the technical field of aluminum alloy building profiles, and provides a high-strength aluminum alloy building material for doors, windows and curtain walls and a preparation method thereof, which comprises the following steps: preparing aluminum alloy raw materials into aluminum alloy rods; sequentially heating, extruding, cooling and sawing the aluminum alloy rods to obtain aluminum alloy profiles, wherein the rod temperature of the aluminum alloy rods after heating is 450-510 DEG C, the extrusion speed is 1-10 m / min, the outlet temperature after extrusion is greater than or equal to 515 DEG C, and the cooling speed is such that the cooling time for reducing the temperature to 100 DEG C is less than or equal to 2 min; and aging the aluminum alloy profiles to obtain the high-strength aluminum alloy building material, wherein the aging temperature is 160-210 DEG C, and the holding time for aging is 2-12 h. The preparation method of the high-strength aluminum alloy building material for doors, windows and curtain walls is optimized in the application, the coupling of the process chain is strengthened, and the obtained aluminum alloy building material has high-strength performance and an elongation after fracture of more than 10%.

Description

Technical Field

[0001] This application relates to the field of aluminum alloy building profile technology, and in particular to a high-strength aluminum alloy building material for doors, windows and curtain walls and its preparation method. Background Technology

[0002] Aluminum alloy building profiles refer to materials with specific cross-sectional shapes and dimensions, made from aluminum alloy through processes such as extrusion, cutting, and drilling. They are mainly used in building doors, windows, curtain walls, roofs, and other structures. Currently, the aluminum alloy building profiles widely used in industry are generally produced using 6063 material. 6063 material is an aluminum-magnesium-silicon alloy, belonging to the 6-series aluminum alloys. Its specific composition includes aluminum (Al), magnesium (Mg), and silicon (Si), with magnesium content ranging from 0.45% to 0.9% and silicon content ranging from 0.2% to 0.6%. Furthermore, 6063-T5 refers to profiles that, after high-temperature forming and natural cooling, undergo artificial aging treatment (170℃~180℃ for 6h~8h) to ensure uniform precipitation of the Mg2Si phase, ultimately achieving the performance characteristics of 6063-T5: tensile strength ≥160MPa, yield strength >110MPa, and elongation after fracture ≥8%.

[0003] In existing technologies, such as the patent with publication number CN107686915A, a 6063 aluminum profile is disclosed, which is composed of the following alloy composition by weight percentage: Si 0.42-0.45%, Mg 0.58-0.62%, Fe≤0.15%, Cu≤0.1%, Cr 0.04-0.05%, Nb≤0.05%, YAG:Ce phosphor≤0.005%, La≤0.05%, with the balance being Al. Through appropriate composition adjustments, the rheological properties of the alloy are enhanced, extrusion pressure is reduced, extrusion speed is increased, and machinability is improved. Furthermore, through specific process design, the material microstructure is made more uniform, and the plastic extrusion performance is significantly improved, giving the 6063 aluminum profile better comprehensive mechanical properties. The tensile strength of the aluminum profile is ≥200 MPa, and the elongation after fracture is ≥12%. Although the above-mentioned aluminum profile has a sufficiently high elongation after fracture, its strength is not high enough to meet the requirements of high-strength building materials in special scenarios.

[0004] To meet the high-strength requirements of modern industry, especially in areas prone to strong winds and typhoons, or in large-section applications, high-strength aluminum alloy building profiles are gradually becoming the mainstream. Building materials made of aluminum alloys such as 6005 (6005 belongs to the Al-Mg series of rust-resistant aluminum alloys and is a representative of medium-strength aluminum alloys, with main alloying elements including magnesium, silicon, and iron) and 6061 (6061 belongs to the Al-Mg-Si series of heat-treated strengthening alloys, with the core components being magnesium (Mg 0.8%~1.2%) and silicon (Si 0.4%~0.8%), forming the strengthening phase Mg2Si, and also containing a small amount of copper (Cu 0.15%~0.4%)) have significantly improved mechanical properties such as tensile strength and yield strength. For example, 6005-T5 has a tensile strength ≥270MPa, a yield strength >250MPa, and an elongation after fracture ≥6%; 6061-T6 has a tensile strength ≥265MPa, a yield strength >245MPa, and an elongation after fracture ≥8%.

[0005] However, when the aforementioned aluminum alloy material is used to produce strip-insulated building profiles (strip-insulated aluminum profiles are composite structural materials formed by connecting aluminum profiles with nylon thermal insulation strips, using mechanical strip insertion and roll forming processes to construct thermal bridges), due to process requirements, the profiles need to undergo operations such as toothing, rolling, and pressing to achieve a composite connection between the aluminum profile and the thermal insulation strip, forming a structural unit that blocks heat conduction. However, during the pressing process, the aluminum alloy profiles may crack, resulting in scrap and a very low yield. This is because, with existing production processes based on the aforementioned aluminum alloy material, building materials, while maintaining high tensile strength and yield strength, rarely achieve an elongation at break exceeding 10%.

[0006] Therefore, there is a need to develop an aluminum alloy building material that can simultaneously meet the requirements of high strength and high elongation. Summary of the Invention

[0007] In view of the shortcomings of the prior art, the present invention provides a high-strength aluminum alloy building material for doors, windows and curtain walls and a method for preparing the same. By optimizing the process parameters, the aluminum alloy building material can achieve a high elongation after fracture of more than 10% with high strength performance.

[0008] To achieve the above objectives, the present invention adopts the following technical solution:

[0009] The first aspect of this invention provides a method for preparing high-strength aluminum alloy building materials for doors, windows, and curtain walls, comprising the following steps:

[0010] (1) Prepare aluminum alloy rods from aluminum alloy raw materials;

[0011] (2) The aluminum alloy rod is heated, extruded, cooled and sawn in sequence to obtain aluminum alloy profile. The rod temperature of the aluminum alloy rod after heating is 450℃~510℃, the extrusion speed is 1m / min~10m / min, the outlet temperature after extrusion is ≥515℃, and the cooling rate is the cooling time to 100℃ is ≤2min.

[0012] (3) Aluminum alloy profiles are subjected to aging treatment to obtain high-strength aluminum alloy building materials, wherein the aging treatment temperature is 160℃~210℃ and the aging treatment holding time is 2h~12h.

[0013] Furthermore, the extrusion speed in step (2) is 2 m / min to 5 m / min.

[0014] Furthermore, the outlet temperature after extrusion in step (2) is 515℃~530℃.

[0015] Furthermore, the cooling method in step (2) is selected from at least one of air cooling, mist cooling, and water cooling.

[0016] Furthermore, during the cooling process in step (2), the length of the cooling path is ≤10m.

[0017] Furthermore, the heat preservation time for aging treatment in step (3) is 8h to 10h.

[0018] Furthermore, in step (1), the aluminum alloy raw material is selected from 6061 type aluminum alloy or 6005 type aluminum alloy.

[0019] A second aspect of the present invention provides a high-strength aluminum alloy building material for doors, windows and curtain walls, which is prepared according to the above-described preparation method.

[0020] Furthermore, the elongation after fracture of high-strength aluminum alloy building materials is ≥10%, while the tensile strength is ≥280MPa and the yield strength is ≥250MPa.

[0021] Furthermore, the elongation after fracture of high-strength aluminum alloy building materials is 10% to 14%, while the tensile strength is 280 MPa to 320 MPa and the yield strength is 250 MPa to 280 MPa.

[0022] The beneficial technical effects of this invention are as follows:

[0023] This invention, through extensive experimental research, creatively discovers that aluminum alloy building materials are highly sensitive to process parameters during preparation. Product performance is closely related to process parameters; if any parameter fails to meet requirements, the final product will struggle to meet performance specifications. This invention optimizes and finely adjusts multiple process parameters in the preparation method of high-strength aluminum alloy building materials for doors, windows, and curtain walls, strengthening the coupling of the process chain to ensure the final product meets the mechanical property requirements of high strength and high elongation. For building materials made from 6061 or 6005 aluminum alloys, dynamic parameter control and synergistic optimization are performed on the following parameters during processing: rod temperature after heating, extrusion speed, outlet temperature after extrusion, cooling rate, aging treatment temperature, and holding time. Optimizing the rod temperature and extrusion speed after heating improves the solubility of alloying elements and deformation uniformity in the building material; optimizing the outlet temperature and cooling rate after extrusion affects the nucleation of precipitated phases; and optimizing aging treatment parameters optimizes the growth and distribution of precipitated phases. This results in a simultaneous improvement in the tensile strength, yield strength, and elongation after fracture of the prepared aluminum alloy building material.

[0024] The aluminum alloy building material of the present invention can ensure that no cracks occur during the pressing process when it is used to produce strip-type thermal insulation building profiles, thus meeting the high strength and durability requirements of aluminum alloy building materials for doors, windows and curtain walls in special scenarios such as typhoons in special regions and large cross sections.

[0025] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Detailed Implementation

[0026] Unless otherwise defined, all technical and / or scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It should be understood that certain features of the invention (described in the context of separate embodiments for clarity) may also be provided in combination in a single embodiment. Conversely, multiple features of the invention (described in the context of a single embodiment for brevity) may also be provided separately or in any suitable combination or, where appropriate, in any other described embodiment of the invention. Certain features described in the context of various embodiments will not be considered essential features of those embodiments unless the embodiment is inoperable without those elements. The invention is further illustrated below by specific examples; however, it should be noted that the specific process conditions and results described in the embodiments of the invention are merely illustrative and should not be construed as limiting the scope of protection of the invention. All equivalent changes or modifications made in accordance with the spirit and essence of the invention should be covered within the scope of protection of the invention.

[0027] First, it should be noted that the raw materials used in the embodiments and comparative examples of this application are all commercially available.

[0028] In areas prone to strong winds and typhoons, or in applications with large cross-sections, aluminum alloy building profiles are required to have high tensile strength and yield strength. However, when using existing high-strength aluminum alloy building profiles to produce strip-insulated building profiles, the profiles need to undergo operations such as toothing, rolling, and pressing to create a composite connection between the aluminum profile and the insulation strip, forming a structural unit that blocks heat conduction. During the pressing process, high-strength aluminum alloy profiles may crack, resulting in defective products. The main reason is that existing production processes based on high-strength aluminum alloy profiles, while maintaining high tensile and yield strength, struggle to achieve an elongation at break of more than 10%. Elongation at break directly reflects a material's plastic deformation capacity or ductility. Aluminum alloys with high elongation at break can withstand significant plastic deformation before fracture, exhibiting excellent ductility. When subjected to external forces (such as impact, bending, or tension), they first undergo significant shape changes (plastic deformation), absorbing a large amount of energy, before slowly undergoing ductile fracture.

[0029] To address the above problems, this invention provides a method for preparing high-strength aluminum alloy building materials for doors, windows, and curtain walls, comprising the following steps:

[0030] (1) Prepare aluminum alloy rods from aluminum alloy raw materials;

[0031] (2) The aluminum alloy rod is heated, extruded, cooled and sawn in sequence to obtain aluminum alloy profile. The rod temperature of the aluminum alloy rod after heating is 450℃~510℃, the extrusion speed is 1m / min~10m / min, the outlet temperature after extrusion is ≥515℃, and the cooling rate is the cooling time to 100℃ is ≤2min.

[0032] (3) Aluminum alloy profiles are subjected to aging treatment to obtain high-strength aluminum alloy building materials, wherein the aging treatment temperature is 160℃~210℃ and the aging treatment holding time is 2h~12h.

[0033] In one embodiment of this application, the aluminum alloy raw material in step (1) is selected from 6061 type aluminum alloy or 6005 type aluminum alloy, wherein,

[0034] The mass percentages of each element in the 6005 aluminum alloy are as follows: Si 0.6%–0.9%, Fe ≤0.35%, Cu ≤0.1%, Mn ≤0.1%, Mg 0.4%–0.6%, Cr ≤0.1%, Zn ≤0.1%, Ti ≤0.1%, other individual impurities ≤0.05%, unavoidable impurities total ≤0.15%, and the balance is Al.

[0035] The mass percentages of each element in 6061 aluminum alloy are as follows: Si 0.4%-0.8%, Fe≤0.7%, Cu0.15%~0.40%, Mn≤0.15%, Mg0.8%-1.2%, Cr0.04%-0.35%, Zn≤0.25%, Ti≤0.15%, other individual impurities ≤0.05%, unavoidable impurities total 0.15%, and the balance is Al.

[0036] In one embodiment of this application, in step (1), the aluminum alloy raw material is melted, refined, and cast to obtain an aluminum alloy rod. The melting, refining, and casting use existing processes (using existing special equipment such as electric resistance furnaces, which will not be described in detail here), for example:

[0037] When the aluminum alloy raw material is 6005 type aluminum alloy, the melting temperature is 720℃~760℃, the refining temperature is 715℃~735℃, and the casting temperature is 680℃~720℃.

[0038] When the aluminum alloy raw material is 6061 type aluminum alloy, the melting temperature is 730℃~750℃, the refining temperature is 735℃~745℃, and the casting temperature is 720℃~740℃.

[0039] In one embodiment of this application, the aluminum alloy rod is heated in step (2), and the temperature of the aluminum alloy rod after heating is 450℃~510℃. For example, it can be 450℃, 460℃, 470℃, 480℃, 490℃, 500℃ and 510℃, but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable. Since the temperature of the aluminum alloy rod after heating directly affects the fluidity of the alloy melt, if the temperature is insufficient, it will lead to an increase in deformation resistance during subsequent extrusion, and easily generate defects such as surface cracks. Furthermore, controlling the temperature of the aluminum alloy rod after heating can ensure that the alloy elements are fully dissolved and form a uniform supersaturated solid solution. For example, if the temperature of the 6061 type aluminum alloy rod after heating is insufficient, it is difficult to dissolve the Mn element, which will affect its yield strength and other properties after extrusion. Therefore, this application optimizes the temperature parameters of the aluminum alloy rod after heating.

[0040] In one embodiment of this application, the extrusion speed of the aluminum alloy rod is controlled in step (2). The extrusion speed is 1 m / min to 10 m / min, for example, it can be 1 m / min, 2 m / min, 3 m / min, 4 m / min, 5 m / min, 6 m / min, 7 m / min, 8 m / min, 9 m / min and 10 m / min, but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable. The extrusion speed of the aluminum alloy rod is related to its deformation rate. When the extrusion speed is insufficient, the alloy grain refinement effect is poor, and the tensile strength decreases after cooling. When the extrusion speed is too fast, deformation heat accumulation will occur, affecting the subsequent cooling effect. Therefore, this application optimizes the extrusion speed parameters.

[0041] In one embodiment of this application, the exit temperature of the elongated aluminum alloy profile formed after extrusion of the aluminum alloy bar is controlled in step (2). The exit temperature after extrusion is ≥515℃, and can reach up to 530℃. For example, it can be 515℃, 520℃, 525℃ and 530℃, but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable. The exit temperature after extrusion of the aluminum alloy bar determines the quenching and cooling start point. If the temperature is too high, the cooling rate will be insufficient, which will lead to the decomposition of the supersaturated solid solution and the precipitation of coarse Mg2Si phase, affecting the improvement of the elongation after fracture. Therefore, this application optimizes the exit temperature parameters after extrusion.

[0042] In one embodiment of this application, the cooling method in step (2) is selected from at least one of air cooling, mist cooling, and water cooling, wherein water cooling includes large water cooling and through-water cooling.

[0043] Air cooling is either natural or forced cooling, which removes heat through air convection. The cooling rate is controlled to prevent deformation or cracking of the aluminum alloy. The air cooling rate is 0.5℃ / s to 4℃ / s, and it is suitable for thin-walled aluminum alloy profiles such as 6061 and 6005.

[0044] Fog cooling is a type of air-mist mixed cooling. It balances the cooling rate and deformation control by mixing atomized water droplets with air. The cooling rate is 5℃ / s to 15℃ / s, and it is suitable for thinner aluminum alloy profiles such as 6061 and 6005 types.

[0045] Water cooling is achieved through spraying or immersion cooling, which rapidly cools the material by using high-velocity water flow to improve its strength. The cooling rate is 20℃ / s to 50℃ / s, and it is suitable for profiles with thicker walls, such as 6061 aluminum alloy and 6005 aluminum alloy.

[0046] Large water cooling is a type of high-pressure water flow impact cooling, which achieves rapid cooling by impacting with high-pressure water flow, breaking through the critical cooling rate of materials. The cooling rate is >100℃ / s, and it is suitable for rapid quenching of special cross-sections such as large thick-walled pipes.

[0047] Water-cooling is a continuous water flow cooling method that achieves uniform and rapid cooling through dynamic water flow contact, reducing thermal stress. The cooling rate is 30℃ / s to 80℃ / s, suitable for large aluminum alloys or irregular profiles such as 6061-T6. This application selects appropriate cooling methods based on the different aluminum alloy raw materials; it can be a single cooling method or a combination of multiple methods, such as first air cooling followed by water cooling for 6061 aluminum alloys.

[0048] In one embodiment of this application, during the cooling process in step (2), the length of the cooling path for the extruded elongated aluminum alloy profile is ≤10m. A cooling path length of less than 10m allows for rapid cooling over a short distance within the critical temperature range below approximately 200°C, which is beneficial for grain refinement and prevents the formation of coarse precipitates. An excessively long cooling path exacerbates the temperature difference between the beginning and end of the profile and the temperature difference across the cross-section, leading to stress differences, uneven performance, and deformation. The core purpose of this application's cooling length of ≤10m is to achieve high-quality production of aluminum alloy profiles through thermal stress control, phase transformation uniformity assurance, and production line efficiency optimization. Specifically, the cooling length for 6061 aluminum alloy bars can be 8m to 10m, and the cooling length for 6005 aluminum alloy bars can be 7m to 9m.

[0049] In one embodiment of this application, the cooling rate in step (2) is such that the cooling time to 100°C is ≤2 min. For example, it can be 110s, 100s, 90s, 80s, 70s, and 60s, but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable. The purpose of this cooling rate is to suppress the precipitation of the second phase (the second phase specifically refers to the strengthening phase (such as Mg2Si) or impurity phase (Al-Fe-Si phase) formed by solute atoms (such as Mg, Si, Cu, Zn, etc.) or compounds, other than the matrix phase (α-Al solid solution)) through rapid cooling, retain the supersaturated solid solution, and create optimal conditions for subsequent aging strengthening.

[0050] In one embodiment of this application, the sawing in step (2) is carried out by mechanical cutting using special equipment such as a circular saw or a band saw. The sawing method adopts existing technology and will not be described in detail here.

[0051] In one embodiment of this application, the aging treatment temperature in step (3) is 160℃~210℃, for example, it can be 160℃, 170℃, 180℃, 190℃, 200℃ and 210℃, but is not limited to the listed values, and other unlisted values ​​within the above range are also applicable. The accuracy of temperature control for aging treatment directly affects the microstructure and properties of the material. This application achieves the following objectives by controlling the temperature of aging treatment: 1) Avoiding over-aging and under-aging: Over-aging refers to a temperature that is too high, such as exceeding the solid solubility curve temperature of the alloy, which will cause the precipitated phase to coarsen, such as Mg2Si phase size >100nm, misalignment cutting becomes bypass mechanism, and strength decreases; under-aging refers to a temperature that is too low, such as below the nucleation temperature of the precipitated phase, the solute atoms do not diffuse sufficiently, the number of precipitated phases is small and the distribution is uneven, and effective strengthening cannot be formed. 2) Suppressing the formation of non-equilibrium phases: High temperatures, such as exceeding 250℃, may induce the precipitation of brittle phases such as Al-Fe-Si, destroying the grain boundary continuity. 3) Matching alloy composition characteristics: Different alloys have significantly different aging responses. For example, the aging temperature of 6005 aluminum alloy rod is 170℃~190℃, and the aging temperature of 6061 aluminum alloy rod is 190℃~210℃.

[0052] In one embodiment of this application, the holding time for aging treatment in step (3) is 2h to 12h, for example, it can be 2h, 3h, 4h, 5h, 6h, 7h, 8h, 9h, 10h, 11h and 12h, but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable. The purpose of precisely controlling the holding time in the aging treatment of this application is to optimize the performance of building materials by regulating the nucleation, growth and coarsening process of the precipitated phase. For example, if the holding time of the 6061 aluminum alloy rod is insufficient, the precipitated phase will not be fully formed, affecting its yield strength; if the holding time of the 6005 aluminum alloy rod is too long, the precipitated phase will coarsen and melt, affecting its tensile strength and yield strength.

[0053] This invention also provides a high-strength aluminum alloy building material for doors, windows, and curtain walls, prepared according to the above-described method. The resulting high-strength aluminum alloy building material has an elongation at break ≥10%, a tensile strength ≥280 MPa, and a yield strength ≥250 MPa. Further, the high-strength aluminum alloy building material has an elongation at break of 10%–14%, a tensile strength of 280 MPa–320 MPa, and a yield strength of 250 MPa–280 MPa.

[0054] This invention optimizes and adjusts multiple process parameters to ensure the final product meets the mechanical property requirements of high strength and high elongation. For building materials made from 6061 or 6005 aluminum alloys, dynamic parameter control and synergistic optimization are performed on the rod temperature after heating, extrusion speed, post-extrusion exit temperature, cooling rate, aging treatment temperature, and holding time. This allows the prepared aluminum alloy building materials to achieve both high strength and improved elongation. When used in the production of strip-type insulated building profiles, the aluminum alloy building materials of this invention ensure no cracking occurs during the pressing process, meeting the high strength and durability requirements for aluminum alloy building materials used in doors, windows, and curtain walls under special conditions such as typhoons in certain regions and large cross-sections.

[0055] The present invention will be described in detail below through specific examples and embodiments. It should also be understood that the following embodiments are only for specific illustration of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-essential improvements and adjustments made by those skilled in the art based on the above description of the present invention are within the scope of protection of the present invention. The specific process parameters, etc., in the following examples are merely examples within a suitable range; that is, those skilled in the art can make appropriate selections within the appropriate range based on the description herein, and are not intended to be limited to the specific values ​​in the examples below.

[0056] Example 1

[0057] (1) The 6005 aluminum alloy is melted, refined and cast to prepare a 6005 aluminum alloy rod. The mass percentage of each element in the 6005 aluminum alloy is: Si 0.67%, Fe 0.1%, Cu 0.1%, Mn 0.1%, Mg 0.60%, Cr 0.08%, Zn 0.1%, Ti 0.1%, unavoidable impurities total 0.15%, and the balance is Al.

[0058] When the aluminum alloy raw material is 6005 type aluminum alloy, the melting temperature is 760℃, the refining temperature is 735℃, and the casting temperature is 720℃.

[0059] (2) The 6005 aluminum alloy rod is heated, extruded, cooled and sawn in sequence to obtain the 6005 aluminum alloy profile. The rod temperature after heating is 480℃, the extrusion speed is 2m / min, the outlet temperature after extrusion is 515℃, the cooling speed is 2min, and the cooling method is water cooling.

[0060] (3) The 6005 type aluminum alloy profile is subjected to aging treatment to obtain high-strength aluminum alloy building materials. The aging treatment temperature is 190℃ and the aging treatment time is 8h.

[0061] Example 2

[0062] (1) 6061 aluminum alloy is melted, refined and cast to prepare 6061 aluminum alloy rods. The mass percentage of each element in the 6061 aluminum alloy is as follows: Si 0.54%, Fe 0.18%, Cu 0.19%, Mn 0.13%, Mg 0.89%, Cr 0.17%, Zn 0.07%, Ti 0.03%, unavoidable impurities total 0.15%, and the balance is Al.

[0063] When the aluminum alloy raw material is 6061 type aluminum alloy, the melting temperature is 750℃, the refining temperature is 745℃, and the casting temperature is 740℃.

[0064] (2) The 6061 aluminum alloy rod is heated, extruded, cooled and sawn in sequence to obtain the 6061 aluminum alloy profile. The rod temperature after heating is 490℃, the extrusion speed is 4m / min, the outlet temperature after extrusion is 520℃, the cooling speed is 2min, and the cooling method is mist cooling.

[0065] (3) The 6061 aluminum alloy profile is subjected to aging treatment to obtain high-strength aluminum alloy building materials. The aging treatment temperature is 190℃ and the aging treatment holding time is 12h.

[0066] Example 3

[0067] The difference between this embodiment and embodiment 1 is that: (2) 6005 aluminum alloy rods are heated, extruded, cooled and sawn in sequence to obtain 6005 aluminum alloy profiles. The temperature of the aluminum alloy rod after heating is 500℃, the extrusion speed is 2m / min, the outlet temperature after extrusion is 515℃, the cooling speed is 2min for cooling down to 100℃, and the cooling method is water cooling.

[0068] Example 4

[0069] The difference between this embodiment and Embodiment 1 is that:

[0070] (2) The 6005 aluminum alloy rod is heated, extruded, cooled and sawn in sequence to obtain the 6005 aluminum alloy profile. The rod temperature after heating is 480℃, the extrusion speed is 5m / min, the outlet temperature after extrusion is 525℃, the cooling speed is 2min for cooling down to 100℃, and the cooling method is water cooling.

[0071] Example 5

[0072] The difference between this embodiment and Embodiment 1 is that:

[0073] (2) The 6005 aluminum alloy rod is heated, extruded, cooled and sawn in sequence to obtain the 6005 aluminum alloy profile. The rod temperature after heating is 480℃, the extrusion speed is 2m / min, the outlet temperature after extrusion is 515℃, the cooling speed is 100s, and the cooling method is water cooling.

[0074] Example 6

[0075] The difference between this embodiment and Embodiment 1 is that:

[0076] (3) The 6005 type aluminum alloy profile is subjected to aging treatment to obtain high-strength aluminum alloy building materials. The aging treatment temperature is 170℃ and the aging treatment time is 12h.

[0077] Example 7

[0078] The difference between this embodiment and Embodiment 2 is as follows:

[0079] (2) The 6061 aluminum alloy rod is heated, extruded, cooled and sawn in sequence to obtain the 6061 aluminum alloy profile. The rod temperature after heating is 510℃, the extrusion speed is 4m / min, the outlet temperature after extrusion is 520℃, the cooling speed is 2min for cooling down to 100℃, and the cooling method is mist cooling.

[0080] Example 8

[0081] The difference between this embodiment and Embodiment 2 is as follows:

[0082] (2) The 6061 aluminum alloy rod is heated, extruded, cooled and sawn in sequence to obtain the 6061 aluminum alloy profile. The rod temperature after heating is 490℃, the extrusion speed is 7m / min, the outlet temperature after extrusion is 530℃, the cooling speed is 2min for cooling down to 100℃, and the cooling method is mist cooling.

[0083] Example 9

[0084] The difference between this embodiment and Embodiment 2 is as follows:

[0085] (2) The 6061 aluminum alloy rod is heated, extruded, cooled and sawn in sequence to obtain the 6061 aluminum alloy profile. The rod temperature after heating is 490℃, the extrusion speed is 4m / min, the outlet temperature after extrusion is 520℃, the cooling speed is 90s, and the cooling method is mist cooling.

[0086] Example 10

[0087] The difference between this embodiment and Embodiment 2 is as follows:

[0088] (3) The 6061 type aluminum alloy profile is subjected to aging treatment to obtain high-strength aluminum alloy building materials. The aging treatment temperature is 210℃ and the aging treatment time is 8h.

[0089] Comparative Example 1

[0090] The difference between this comparative example and Example 1 is as follows:

[0091] (2) The 6005 aluminum alloy rod is heated, extruded, cooled and sawn in sequence to obtain the 6005 aluminum alloy profile. The rod temperature after heating is 520℃, the extrusion speed is 2m / min, the outlet temperature after extrusion is 530℃, the cooling speed is 2min, and the cooling method is water cooling.

[0092] Comparative Example 2

[0093] The difference between this comparative example and Example 1 is as follows:

[0094] (2) The 6005 aluminum alloy rod is heated, extruded, cooled and sawn in sequence to obtain the 6005 aluminum alloy profile. The rod temperature after heating is 480℃, the extrusion speed is 2m / min, the outlet temperature after extrusion is 515℃, the cooling speed is 3min for cooling down to 100℃, and the cooling method is water cooling.

[0095] Comparative Example 3

[0096] The difference between this comparative example and Example 1 is as follows:

[0097] (2) The 6005 aluminum alloy rod is heated, extruded, cooled and sawn in sequence to obtain the 6005 aluminum alloy profile. The rod temperature after heating is 480℃, the extrusion speed is 2m / min, the outlet temperature after extrusion is 505℃, the cooling speed is 2min, and the cooling method is water cooling.

[0098] Comparative Example 4

[0099] The difference between this comparative example and Example 1 is as follows:

[0100] (3) The 6005 type aluminum alloy profile is subjected to aging treatment to obtain high-strength aluminum alloy building materials. The aging treatment temperature is 150℃ and the aging treatment time is 12h.

[0101] Comparative Example 5

[0102] The difference between this comparative example and Example 2 is as follows:

[0103] (2) The 6061 aluminum alloy rod is heated, extruded, cooled and sawn in sequence to obtain the 6061 aluminum alloy profile. The rod temperature after heating is 440℃, the extrusion speed is 4m / min, the outlet temperature after extrusion is 515℃, the cooling speed is 2min for cooling down to 100℃, and the cooling method is mist cooling.

[0104] Comparative Example 6

[0105] The difference between this comparative example and Example 2 is as follows:

[0106] (2) The 6061 aluminum alloy rod is heated, extruded, cooled and sawn in sequence to obtain the 6061 aluminum alloy profile. The rod temperature after heating is 490℃, the extrusion speed is 10m / min, the outlet temperature after extrusion is 540℃, the cooling speed is 2min for cooling down to 100℃, and the cooling method is mist cooling.

[0107] Comparative Example 7

[0108] The difference between this comparative example and Example 2 is as follows:

[0109] (2) The 6061 aluminum alloy rod is heated, extruded, cooled and sawn in sequence to obtain the 6061 aluminum alloy profile. The rod temperature after heating is 500℃, the extrusion speed is 4m / min, the outlet temperature after extrusion is 550℃, the cooling speed is 2min for cooling down to 100℃, and the cooling method is mist cooling.

[0110] Comparative Example 8

[0111] The difference between this comparative example and Example 2 is as follows:

[0112] (3) The 6061 aluminum alloy profile is subjected to aging treatment to obtain high-strength aluminum alloy building materials. The aging treatment temperature is 220℃ and the aging treatment time is 8h.

[0113] Performance testing

[0114] Tensile strength: In accordance with GB / T 228.1-2021 standard, the tensile strength of aluminum alloy building materials in each embodiment and each comparative example was tested using a universal testing machine. The test results are shown in Table 1.

[0115] Yield strength: In accordance with GB / T 228.1-2021 standard, the yield strength of aluminum alloy building materials in each embodiment and each comparative example was tested using a unified yield strength test method. The test results are shown in Table 1.

[0116] Elongation after fracture: In accordance with the elongation calculation method and allowable error specified in GB / T 228.1-2021, the elongation after fracture of aluminum alloy building materials in each embodiment and each comparative example was tested, and the test results are shown in Table 1.

[0117] The experimental data and analysis are as follows:

[0118] Table 1. Performance of aluminum alloy building materials in each embodiment and comparative example.

[0119]

[0120]

[0121] As shown in Table 1, the embodiments of this application dynamically control and synergistically optimize the rod temperature, extrusion speed, extrusion outlet temperature, cooling rate, aging treatment temperature, and holding time of the aluminum alloy rod after heating during the processing of building materials using 6061 and 6005 aluminum alloys as raw materials. By optimizing the rod temperature and extrusion speed after heating, the solubility of alloying elements and deformation uniformity in the building materials are optimized; by optimizing the outlet temperature and cooling rate after extrusion, the nucleation of precipitated phases is affected; and by optimizing the aging treatment parameters, the growth and distribution of precipitated phases are optimized. As a result, the tensile strength, yield strength, and elongation after fracture of the prepared aluminum alloy building materials are simultaneously improved, which can solve the problem that the elongation after fracture of high-strength aluminum alloy building materials is difficult to reach more than 10%.

[0122] In the preparation process of the 6005 type aluminum alloy building materials in Comparative Examples 1 to 4, the rod temperature, extrusion speed, outlet temperature after extrusion, and aging treatment control parameters of the heated aluminum alloy rod were not within the range specified in this application. This resulted in uneven precipitate formation, and insufficient cooling led to the decomposition of the supersaturated solid solution, precipitating coarse Mg2Si phases. Consequently, the tensile strength, yield strength, and elongation after fracture of the 6005 type aluminum alloy building materials were all lower than those of Example 1. Although the elongation of Comparative Example 1 could reach more than 10%, its tensile strength and yield strength were significantly lower than those of Example 1.

[0123] In the preparation process of 6061 type aluminum alloy building materials in Comparative Examples 5 to 8, the rod temperature of the heated aluminum alloy rod, the extrusion speed, the outlet temperature after extrusion, and the aging treatment control parameters are not within the range specified in this application, which affects the improvement of properties such as elongation after fracture.

[0124] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A method for preparing high-strength aluminum alloy building materials for doors, windows, and curtain walls, characterized in that, Includes the following steps: (1) Prepare aluminum alloy rods from aluminum alloy raw materials; (2) The aluminum alloy rod is heated, extruded, cooled and sawn in sequence to obtain an aluminum alloy profile. The rod temperature of the aluminum alloy rod after heating is 480℃, the extrusion speed is 2m / min, the outlet temperature after extrusion is 515℃, and the cooling speed is ≤2min for cooling down to 100℃. (3) The aluminum alloy profile is subjected to aging treatment to obtain the high-strength aluminum alloy building material, wherein the aging treatment temperature is 190℃ and the aging treatment holding time is 8h; The aluminum alloy raw material mentioned in step (1) is selected from 6061 type aluminum alloy or 6005 type aluminum alloy; During the cooling process in step (2), the length of the cooling path is ≤10m; The high-strength aluminum alloy building material has an elongation at break of 10% to 14%, a tensile strength of 280 MPa to 320 MPa, and a yield strength of 250 MPa to 280 MPa.

2. The preparation method according to claim 1, characterized in that, The cooling method in step (2) is selected from at least one of air cooling, mist cooling, and water cooling.

3. A high-strength aluminum alloy building material for doors, windows, and curtain walls, characterized in that, The high-strength aluminum alloy building material is prepared according to the preparation method described in claim 1 or 2.

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