6-series aluminum alloy material, extruded profile and preparation method and application of 6-series aluminum alloy material and extruded profile

Abstract

The invention belongs to the technical field of aluminum alloy material development, and particularly relates to a 6-series aluminum alloy material, an extruded profile and a preparation method and application of the 6-series aluminum alloy material and the extruded profile. The aluminum alloy material comprises the following elements in percentage by mass: 0.65-0.9% of Si (silicon); 0.85%-1.1% of Mg (magnesium); 0.5%-0.8% of Cu (copper); mn (manganese): 0.05%-0.18%; 0.05% to 0.15% of Cr (chromium); zn (zinc) is less than or equal to 0.1%; ti (titanium) is less than or equal to 0.1%; less than or equal to 0.15% of Fe (iron); and the balance of Al (aluminum) and inevitable impurities. The aluminum alloy material provided by the invention has excellent mechanical properties and corrosion resistance, has remarkable advantages in the aspects of high strength, light weight, processability and cost control compared with a conventional 6-series aluminum alloy, and is particularly suitable for being applied to severe environments, such as offshore photovoltaic module structural members, photovoltaic modules, photovoltaic modules, photovoltaic modules, photovoltaic modules, photovoltaic modules, photovoltaic modules and the like. The material consumption can be effectively reduced, the service life is prolonged, and the maintenance cost is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of aluminum alloy material development, and in particular relates to a 6 series aluminum alloy material, an extruded profile, and a preparation method and application thereof. Background Art

[0002] With the growing global demand for renewable energy, solar photovoltaic power generation technology has been widely used. As a key component of solar photovoltaic power generation systems, the material selection and design optimization of photovoltaic structural parts have an important impact on the overall performance, cost and service life of the system. Aluminum alloy profiles have become the preferred material for solar photovoltaic structural parts due to their excellent properties such as light weight, corrosion resistance and easy processing. Among them, 6 series aluminum alloys have been widely used in photovoltaic structural parts due to their good comprehensive performance.

[0003] 6 series aluminum alloy belongs to Al-Mg-Si alloy, which has medium strength, good formability, weldability and corrosion resistance, and is suitable for a variety of structural parts. According to the national standard GB / T3190-2020, common 6 series aluminum alloys include 6063, 6005, 6061, 6013, 6066 and 6082. The composition of these aluminum alloys is shown in Table 1. The difference in composition is mainly reflected in the content of elements such as silicon (Si), magnesium (Mg), copper (Cu), and manganese (Mn), which affects their mechanical properties and processing properties.

[0004] Table 1

[0005]

[0006]

[0007] Material strength is one of the key factors affecting the design of photovoltaic structural parts. With the improvement of material strength, the cross-sectional size and wall thickness of the structural parts can be reduced while meeting the same performance requirements, thereby achieving material savings and system lightweighting. Table 2 shows the application of aluminum alloy materials of different grades and states in photovoltaic power generation load-bearing components. It can be seen from the table that as the tensile strength of the material increases from 160MPa (6063T5) to 260MPa (6005T6), the frame section height and wall thickness are reduced. For example, the frame section height of 6063T5 is 45mm and the wall thickness is 1.8mm, while the frame section height of 6005T6 is reduced to 30mm and the wall thickness is reduced to 1.3mm. This design optimization not only reduces the amount of material used, but also reduces the weight of the overall structure, reducing transportation and installation costs.

[0008] Table 2

[0009]

[0010] In recent years, offshore photovoltaics, as an emerging form of photovoltaic applications, has gradually attracted attention and shown great development potential. Compared with land photovoltaics, offshore photovoltaics have unique advantages: first, the vast ocean area and huge available space can effectively alleviate the problem of land shortage for land photovoltaics; second, offshore photovoltaic power stations are usually built in offshore areas, with less obstruction, excellent lighting conditions, and higher power generation efficiency; in addition, the cooling effect of seawater on photovoltaic modules helps to reduce the module temperature and further improve power generation efficiency. According to statistics, the power generation of offshore photovoltaics can be 10%-15% higher than that of land photovoltaics under the same conditions.

[0011] However, the marine environment is characterized by high humidity, high salt spray, strong winds and waves, which puts more stringent requirements on materials. Conventional 6 series aluminum alloys are difficult to achieve both high strength and high corrosion resistance in the marine environment. With the continuous expansion of the scale of photovoltaic power generation systems and the continuous compression of costs, it is particularly important to develop a new type of aluminum alloy material that combines high strength, excellent corrosion resistance and economy. This can not only further reduce the cross-sectional size and wall thickness of structural parts, improve the overall stiffness and stability of the system, extend service life and reduce maintenance costs, but also reduce raw material consumption and carbon emissions, in line with the requirements of sustainable development. Summary of the invention

[0012] In view of the shortcomings of the prior art, the present invention provides a 6 series aluminum alloy material, an extruded profile, and a preparation method and application thereof, with the aim of providing a new aluminum alloy material with high strength, excellent corrosion resistance and economy, so as to better meet the application requirements in harsh environments such as offshore photovoltaic module structural parts.

[0013] The mass content of each element in the aluminum alloy material provided by the present invention is as follows:

[0014] Si (silicon): 0.65%-0.9%;

[0015] Mg (magnesium): 0.85%-1.1%;

[0016] Cu (copper): 0.5%-0.8%;

[0017] Mn (manganese): 0.05%-0.18%;

[0018] Cr (chromium): 0.05%-0.15%;

[0019] Zn(zinc):≤0.1%;

[0020] Ti (titanium): ≤ 0.1%;

[0021] Fe(Iron):≤0.15%;

[0022] The balance is Al (aluminum) and inevitable impurities.

[0023] According to the above aluminum alloy formula, high-performance aluminum alloy profiles can be produced through casting, homogenization treatment, extrusion and artificial aging treatment.

[0024] The aluminum alloy material provided by the present invention preferably adopts the following casting process:

[0025] According to the mass percentage of each element in the aluminum alloy material defined in the present invention, smelting and casting are carried out to obtain a new material cast rod, which mainly includes smelting, tempering, slag removal, refining, standing and casting.

[0026] Melting: Place Al ingots, Mg ingots, Cu ingots, and Al-Si and Al-Mn master alloys in a melting furnace to melt into aluminum alloy solution.

[0027] Tempering: Take samples of the aluminum alloy solution and quickly analyze its composition. Then, add metal elements to temper it to the set aluminum alloy composition range, and then skim, refine and let it stand.

[0028] Casting: The aluminum alloy solution flows into the casting mold through the flow channel, and plate filtration can be performed during the flow channel process. The aluminum alloy solution is cast through a hot top or oil-gas sliding mold to obtain a cast rod.

[0029] The aluminum alloy material provided by the present invention preferably adopts the following single-stage homogenization or two-stage homogenization process:

[0030] Single-stage homogenization: The cast rod is heated to 540-580℃ at a rate of 30-100℃ / h and kept warm for 6-24h; after the insulation is completed, it is cooled to below room temperature at a rate of 100-200℃ / h.

[0031] The heating rate of single-stage homogenization is slow. During the slow heating process, part of the low-temperature soluble phase of Mg2Si or Al2Cu will dissolve back into the aluminum matrix. Therefore, when the temperature reaches 540-580℃, most of the dissolution driving force can be used to dissolve the coarse second phase, thereby improving the homogenization treatment effect.

[0032] Two-stage homogenization: the cast rod is heated to 500-540℃ at a rate of 100-200℃ / h and kept warm for 2-6h; then heated to 540-580℃ at a rate of 100-200℃ / h and kept warm for 6-20h; finally cooled to below room temperature at a rate of 100-200℃ / h.

[0033] The heating rate of two-stage homogenization is fast, and most of the low-temperature soluble phases of Mg2Si or Al2Cu do not have time to dissolve back into the aluminum matrix. Therefore, the first stage is set to a low temperature of 500-540℃ for a short time to make a part of the low-temperature soluble phases of Mg2Si or Al2Cu dissolve back into the aluminum matrix; then the temperature is raised to 540-580℃ for a long time in the second stage, at which time most of the dissolution driving force can be used to dissolve the coarse second phase, thereby improving the homogenization effect.

[0034] The aluminum alloy material provided by the present invention preferably adopts the following extrusion process:

[0035] First, the mold heating temperature is controlled at 430-480℃, the ingot barrel heating temperature is controlled at 430-480℃, and the cast rod is heated to 495-560℃. During extrusion, the extrusion rod push speed is controlled at 3-6mm / s, and the extrusion outlet temperature is maintained at 480-560℃. After the extruded profile comes out, it is quenched online by water spray cooling to ensure that the profile temperature drops below 200℃. Finally, the extruded profile is stretched and straightened as needed, and the stretching rate is controlled below 0.5%.

[0036] The aluminum alloy material provided by the present invention preferably adopts the following single-stage artificial aging or double-stage artificial aging process:

[0037] Single-stage artificial aging: heat to 170-200℃, keep warm for 3-18h, and cool to room temperature with strong wind after coming out of the furnace.

[0038] The implementation of single-stage artificial aging is simply heating to the optimal precipitation temperature range of the Mg2Si strengthening phase. In the optimal precipitation temperature range, the holding time is inversely related or corresponding to the aging temperature. The higher the aging temperature, the shorter the required holding time, and the lower the aging temperature, the longer the required holding time. For example, heating to 200°C and holding for 3h, and heating to 170°C and holding for 18h. This is because if the holding time is too long at a higher aging temperature, it will lead to over-aging, coarsening the Mg2Si phase, thereby reducing the aging hardening effect; and if the holding time is too short at a lower aging temperature, the Mg2Si strengthening phase cannot be fully precipitated to the peak value of quantity and density, and it is difficult to obtain ideal mechanical properties.

[0039] Two-stage artificial aging: heat to 100-130℃, keep warm for 2-4h; then heat to 160-180℃, keep warm for 4-10h.

[0040] The implementation of two-stage artificial aging is mainly to obtain a large number of dense Mg2Si strengthening phases, and then obtain the best mechanical properties. The first stage is set to a low temperature of 100-130℃ for a short time of insulation, the purpose is to form a large number of fine GPZone nuclei in the aluminum matrix. These GPZone nuclei will continue to grow and transform into a large number of fine Mg2Si strengthening phases when they are kept at a high temperature of 160-180℃ in the second stage. Through this two-stage aging treatment, the effect of artificial aging can be significantly improved, and better mechanical properties can be obtained.

[0041] The aluminum alloy material of the present invention can take into account high strength, high corrosion resistance and excellent processing characteristics through element ratio and process control. Among them, the content of Si (silicon) is controlled at 0.65%-0.9%, and forms a Mg2Si strengthening phase with the content of Mg (magnesium) of 0.85%-1.1%. Mg2Si is one of the most important precipitation strengthening phases in aluminum alloys, which can significantly improve the strength, hardness and tensile strength of the alloy. Through reasonable aging treatment, the Mg2Si phase can be uniformly precipitated, further improving the mechanical properties of the material. In addition, the control of the Si content not only ensures the formation of sufficient Mg2Si phase, but also avoids the increase in thermal crack sensitivity caused by excessive Si, ensuring the stability of the material during processing and welding. The content of Cu (copper) is controlled at 0.5%-0.8%, which can effectively improve the strength, hardness and elongation of the aluminum alloy. The Cu element forms an Al2Cu phase in the aluminum alloy, further enhancing the mechanical properties of the material. Although a high Cu content will reduce the corrosion resistance of the material, the influence of the Cu element is minimized through overall control of each element and reasonable process conditions, so that the material still has good corrosion resistance while maintaining high strength. The Mn (manganese) content is controlled at 0.05%-0.18%, which can refine the grain structure of the alloy and improve the mechanical properties of the material. The Mn element can also form an Al6Mn phase with Al, further improving the strength and corrosion resistance of the material. The Cr (chromium) content is controlled at 0.05%-0.15%, which can improve the corrosion resistance, high temperature performance and wear resistance of the material. The Cr element forms a fine Al7Cr phase in the aluminum alloy, further refines the grains and enhances the comprehensive performance of the material. Zn (≤0.1%) and Ti (≤0.1%) have grain refining and strengthening effects to a certain extent. Fe (≤0.15%) enhances strength within an appropriate range without affecting corrosion resistance.

[0042] Through single-stage or double-stage homogenization treatment, the coarse second phase (such as Mg2Si and Al2Cu) can be effectively dissolved, making the alloy composition more uniform and improving the mechanical properties and corrosion resistance of the material. Through reasonable extrusion temperature and speed control, the material can maintain good organizational structure and mechanical properties during the extrusion process. The online quenching process further improves the strength and hardness of the material. Through single-stage or double-stage artificial aging treatment, the Mg2Si phase can be uniformly precipitated, significantly improving the strength and hardness of the material while maintaining good elongation and corrosion resistance.

[0043] Compared with conventional 6 series aluminum alloys, the aluminum alloy material of the present invention exhibits significant advantages in both mechanical properties and corrosion resistance, especially in application scenarios such as offshore photovoltaic module structures that require high strength and high corrosion resistance, and has broad application prospects.

[0044] Beneficial Effects

[0045] The aluminum alloy material provided by the present invention has both excellent mechanical properties and corrosion resistance. The aluminum alloy material has high strength (yield strength 345MPa, tensile strength 382MPa), good hardness (124HV) and good elongation (10.0%), and also has excellent corrosion resistance (after anodizing AA10, 5% neutral salt spray test can reach 4000 hours). Compared with conventional 6 series aluminum alloys, the material of the present invention has significant advantages in lightweight, processing performance and cost control, and is particularly suitable for applications in harsh environments, such as offshore photovoltaic module structures, which can effectively reduce material usage, extend service life and reduce maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 : Stress-strain curve diagram of Experimental Example 0.

[0047] Figure 2 : Stress-strain curve of 6063 aluminum alloy.

[0048] Figure 3 : Stress-strain curve of 6005 aluminum alloy.

[0049] Figure 4 : Stress-strain curve of 6013 aluminum alloy.

[0050] Figure 5 : Metallographic structure diagram of Experimental Example 0 before 5% neutral salt spray test.

[0051] Figure 6 : Metallographic structure diagram of Experimental Example 0 after 5% neutral salt spray test. DETAILED DESCRIPTION

[0052] The present invention is further illustrated by specific examples below. These examples are exemplary and are intended to illustrate the problem and explain the present invention, but are not intended to be limiting.

[0053] Experimental Example 0

[0054] The mass content of each element in aluminum alloy materials is as follows:

[0055] Si (silicon): 0.73%;

[0056] Mg (magnesium): 0.95%;

[0057] Cu (copper): 0.65%;

[0058] Mn (manganese): 0.13%;

[0059] Cr (chromium): 0.10%;

[0060] Zn (zinc): 0.023%;

[0061] Ti (titanium): 0.012%;

[0062] Fe(Iron): 0.12%;

[0063] The balance is Al (aluminum) and inevitable impurities.

[0064] Casting process:

[0065] Al ingots, Mg ingots, Cu ingots, and master alloys of Al-Si and Al-Mn are placed in a smelting furnace to melt into aluminum alloy solution. Samples of the aluminum alloy solution are quickly analyzed for composition, and the above-mentioned aluminum alloy composition is obtained by adding metal elements for quenching and tempering. The aluminum alloy solution is then slag-refined and allowed to stand. The aluminum alloy solution flows into a casting mold through a launder, and is cast using a hot top mold to finally obtain a cast rod.

[0066] Homogenization process:

[0067] Single-stage homogenization: heat the cast rod to 570℃ and keep it warm for 16 hours; after the insulation is completed, cool it to room temperature.

[0068] Extrusion process:

[0069] The mold is heated to 480℃, the ingot barrel is heated to 480℃, and the cast rod is heated to 510℃. During extrusion, the extrusion rod push speed is controlled at 4.5mm / s, and the extrusion outlet temperature is about 510℃. After the extruded profile comes out, it is quenched online by water spray cooling to ensure that the profile temperature drops below 200℃. The extruded profile is stretched and straightened, and the stretching rate is controlled below 0.5%.

[0070] Aging process:

[0071] Single-stage artificial aging: The extruded aluminum alloy profile is heated to 190°C, kept warm for 4.5 hours, and then cooled to room temperature with strong wind after being taken out of the furnace to obtain an aluminum alloy profile.

[0072] Performance Test:

[0073] Aluminum alloy profiles were tested after AA10 anodizing treatment.

[0074] The tests of yield strength, tensile strength and elongation are carried out in accordance with GB / T 228.1-2021 Tensile test of metallic materials Part 1: Test method at room temperature, and the hardness test is carried out in accordance with GB / T 4340.1-2009 Vickers hardness test of metallic materials Part 1: Test method. The test equipment includes a tensile testing machine that complies with ISO 7500-1 and a Vickers hardness tester that complies with ISO 6507-1. The tensile specimens are prepared according to the standard, with a gauge length of 50mm. The hardness specimens are cut from the extruded profiles and polished to a smooth surface without defects. The tensile test is carried out at room temperature (23±2℃) at a speed of 2mm / min until the specimen breaks; the hardness test is carried out under the same room temperature conditions, with a load of 10kg and a holding time of 15 seconds. The test data are averaged after multiple measurements. The yield strength, tensile strength and elongation are the average of three tests, and the hardness test is the average of the measurement results of five different points on each specimen.

[0075] The durability of materials in corrosive environments is evaluated through a 5% neutral salt spray test (NSS). The test is carried out in accordance with the standard "GB / T10125-2021 Artificial Atmosphere Corrosion Test Salt Spray Test", using a 5% sodium chloride solution, a test temperature of 35±2°C, and a continuous spray method. The specimen is cut from the extruded profile, and after the surface is cleaned, it is placed in a salt spray test chamber at an angle of 15° to 30° to test the time it can withstand 5% neutral salt spray.

[0076] The test results are shown in Table 3.

[0077] Table 3

[0078]

[0079] Experimental Example 1

[0080] In this experimental example, the element content is determined according to the national standard 6 series aluminum alloy, and the casting process, homogenization process, extrusion process, and aging process are the same as those of Experimental Example 0. The content of each element in this experimental example is shown in Table 4.

[0081] Table 4

[0082] Element Si Mg Cu Mn Cr Zn Ti Fe Experimental Example 0 0.73 0.95 0.65 0.13 0.10 0.023 0.012 0.12 6063 0.45 0.58 0.006 0.005 0.003 0.021 0.015 0.13 6005 0.66 0.56 0.005 0.004 0.003 0.025 0.014 0.15 6061 0.67 0.96 0.22 0.005 0.08 0.025 0.018 0.17 6013 0.67 0.93 0.69 0.28 0.012 0.022 0.024 0.17 6066 1.12 1.15 0.95 0.83 0.018 0.026 0.019 0.23 6082 1.08 0.72 0.07 0.55 0.015 0.027 0.022 0.21

[0083] The same test method as that of Experimental Example 0 was used to test the yield strength, tensile strength, elongation, hardness and neutral salt spray resistance of the material. The test results are shown in Tables 5 and 6.

[0084] Table 5

[0085]

[0086]

[0087] Table 6

[0088] Test subjects 5% neutral salt spray test H Outdoor weather resistance grade Experimental Example 0 4000 high 6063 3500 high 6005 3500 high 6061 2000 middle 6013 1500 Low 6066 1500 Low 6082 1500 Low

[0089] By comparing the mechanical properties and corrosion resistance of Experimental Example 0 with the national standard 6 series aluminum alloys (6063, 6005, 6061, 6013, 6066, and 6082), it can be found that the aluminum alloy material of Experimental Example 0 has significant comprehensive performance advantages.

[0090] The yield strength of Experimental Example 0 is 345MPa, the tensile strength is 382MPa, the hardness is 124HV, and the elongation is 10.0%. These mechanical properties are much better than those of 6063, 6005, and 6061 aluminum alloys, and are also significantly better than those of 6013 and 6082 aluminum alloys, and only inferior to 6066 aluminum alloy. In particular, in terms of yield strength and tensile strength, Experimental Example 0 is 65.9% and 62.6% higher than 6063, 28.7% and 29.5% higher than 6005, and 18.2% and 19.7% higher than 6061. In addition, the aluminum alloy of Experimental Example 0 also has excellent elongation, indicating that it has good plasticity while maintaining high strength. Figure 1 , Figure 2 , Figure 3 , Figure 4 The stress-strain curves of experimental example 0, 6063, 6005, and 6013 aluminum alloys are shown respectively.

[0091] Through the 5% neutral salt spray test, the corrosion resistance time of Experimental Example 0 can reach 4000 hours, which is higher than the 3500 hours that 6063 and 6005 can achieve, and significantly better than the 1500-2000 hours that 6061, 6013, 6066 and 6082 can achieve, indicating that the aluminum alloy material of Experimental Example 0 is significantly better than the conventional national standard 6 series aluminum alloy in terms of outdoor weather resistance. Figure 5 The metallographic structure of Experiment 0 before the 5% neutral salt spray test is shown. Figure 6 The metallographic structure of Experimental Example 0 after the 5% neutral salt spray test is shown, indicating that the material has excellent corrosion resistance in a salt spray environment. No obvious intergranular corrosion is found in the microstructure after corrosion, indicating that its grain boundary structure is stable and its corrosion resistance is excellent.

[0092] In general, the aluminum alloy material of Experimental Example 0 has achieved comprehensive improvement in mechanical properties and corrosion resistance through composition optimization and process control. Its combination of high strength and high corrosion resistance makes it particularly suitable for application scenarios that require lightweight, high strength and corrosion resistance, especially for use as a structural component of offshore photovoltaic modules.

[0093] In addition, in terms of dimensional accuracy control and anodized appearance, the aluminum alloy material of Experimental Example 0 also has certain advantages over the national standard 6 series aluminum alloy as a whole. The results are shown in Table 7.

[0094] Table 7

[0095] Evaluation object Dimensional accuracy control Anodized appearance Experimental Example 0 high high 6063 high high 6005 high high 6061 middle middle 6013 Low middle 6066 Low Difference 6082 Low Difference

[0096] Among them, dimensional accuracy control and anodized appearance are used to evaluate the difficulty of controlling the processing accuracy of aluminum alloy profiles and the difficulty of surface treatment respectively. Dimensional accuracy is evaluated according to the national standard GB / T 14846-2014, and is divided into three levels: high, medium and low according to the accuracy measurement results. Anodized appearance is evaluated through surface defect inspection and gloss inspection, and is divided into three levels: high, medium and low.

[0097] The results show that Experimental Example 0 exhibits a high level in both dimensional accuracy and anodized appearance, indicating its easy processing and surface treatment characteristics.

[0098] In terms of raw material cost, the aluminum alloy material of Experimental Example 0 also has certain advantages over the national standard 6 series aluminum alloy as a whole. The results are shown in Table 8.

[0099] Table 8

[0100]

[0101] Among them, the difference in casting rod costs is mainly obtained by evaluating the long-term market average price of elements required for different types of aluminum alloys. The total raw material cost mainly includes the original aluminum cost and the casting rod cost. The mold loss cost is calculated by allocating the mold cost to the amount of aluminum alloy that can be processed during the mold's service life. The profile production cost mainly includes the total raw material cost and the mold loss cost.

[0102] The results show that although the aluminum alloy material of Experimental Example 0 has an increased cost in casting rods compared to 6063 and 6005, its casting rod cost is still at a medium level compared to alloys such as 6013, 6066 and 6082. In terms of total raw material cost, Experimental Example 0 is similar to 6061 and lower than 6013, 6066 and 6082. In terms of mold loss cost, Experimental Example 0 is at the lowest level, lower than the medium-cost 6063 and 6005, and lower than the high-cost 6013, 6066 and 6082. In general, Experimental Example 0 performs well in cost control and can achieve extremely high comprehensive performance at a medium cost, so it has significant competitiveness in terms of cost performance.

[0103] Experimental Example 2

[0104] In this experimental example, the element content of the 6-series aluminum alloy of the present invention is adjusted, and the casting process, homogenization process, extrusion process, and aging process are the same as those of Experimental Example 0. The content of each element in this experimental example is shown in Table 9.

[0105] Table 9

[0106]

[0107] The same test method as that of Experimental Example 0 was used to test the yield strength, tensile strength, elongation, hardness and neutral salt spray resistance of the material. The test results are shown in Table 10.

[0108] Table 10

[0109]

[0110] The results show that Experimental Examples 2.1 and 2.2 can also achieve better mechanical properties and corrosion resistance.

[0111] Experimental Example 3

[0112] The element content, casting process, extrusion process, and aging process of this experimental example are the same as those of Experimental Example 0, and the difference lies in the homogenization process.

[0113] This experimental example adopts the following two-stage homogenization process: the cast rod is heated to 530°C and kept at this temperature for 3 hours; then heated to 570°C and kept at this temperature for 10 hours; and finally cooled to room temperature.

[0114] The same test method as in Experimental Example 0 was used to test the yield strength, tensile strength, elongation and hardness of the material. The test results are shown in Table 11.

[0115] Table 11

[0116]

[0117] The effects of single-stage homogenization (570℃×16h) and double-stage homogenization (530℃×3h+570℃×10h) on the mechanical properties of aluminum alloys with the composition of the present invention after extrusion were compared experimentally. The results show that there is little difference in tensile strength, yield strength, hardness and elongation between Experimental Example 0 (single-stage homogenization) and Experimental Example 3 (double-stage homogenization). Specifically, the tensile strength of Experimental Example 0 is 382MPa, while the tensile strength of Experimental Example 3 is 385MPa, with a difference of only 3MPa. In addition, the yield strength, hardness and elongation of Experimental Example 3 are 347MPa, 125HV and 10.4%, respectively, which are smaller than 345MPa, 124HV and 10.0% of Experimental Example 0. These data show that whether it is single-stage or double-stage homogenization, as long as the homogenization temperature and time are reasonably prepared, the homogenization process has limited effect on the mechanical properties of the final extruded profile. Therefore, in actual production, the homogenization method can be flexibly selected according to equipment conditions and process requirements without excessively worrying about its significant impact on material properties.

[0118] Experimental Example 4

[0119] The element content, casting process, homogenization process, and extrusion process of this experimental example are the same as those of Experimental Example 0, and the difference lies in the aging process.

[0120] Experimental Example 4.1 adopts the following single-stage artificial aging process: the extruded aluminum alloy profile is heated to 180°C, kept at this temperature for 8 hours, and then cooled to room temperature by strong wind after being taken out of the furnace.

[0121] Experimental Example 4.2 adopts the following single-stage artificial aging process: the extruded aluminum alloy profile is heated to 200°C, kept at this temperature for 2.5 hours, and then cooled to room temperature by strong wind after being taken out of the furnace.

[0122] Experimental Example 4.3 adopts the following two-stage artificial aging process: the extruded aluminum alloy profile is heated to 125°C, kept at this temperature for 2 hours, then heated to 170°C, kept at this temperature for 8 hours, and then cooled to room temperature by strong wind after being taken out of the furnace.

[0123] The same test method as in Experimental Example 0 was used to test the yield strength, tensile strength, elongation and hardness of the material. The test results are shown in Table 12.

[0124] Table 12

[0125]

[0126] By comparing the artificial aging processes of Experimental Example 0, Experimental Example 4.1, Experimental Example 4.2 and Experimental Example 4.3, the effects of different aging methods on the mechanical properties of the aluminum alloy after extrusion of the composition of the present invention were studied. Specifically, Experimental Example 0 adopts a single-stage artificial aging process (190℃×4.5h), Experimental Example 4.1 adopts a single-stage artificial aging process (180℃×8h), Experimental Example 4.2 adopts a single-stage artificial aging process (200℃×2.5h), and Experimental Example 4.3 adopts a double-stage artificial aging process (125℃×2h+170℃×8h). The test results show that different aging processes have little effect on the mechanical properties of aluminum alloys. Whether it is a single-stage or double-stage artificial aging process, as long as the temperature and time are reasonably prepared, the artificial aging method has limited effect on the mechanical properties of the final extruded profile. Therefore, in actual production, the aging process can be flexibly selected according to equipment conditions and process requirements without excessively worrying about its significant impact on material properties.

[0127] Experimental Example 5

[0128] The element content, casting process, homogenization process, and aging process of this experimental example are the same as those of Experimental Example 0, and the difference lies in the extrusion process.

[0129] Experimental Example 5.1 adopts the following extrusion process: the die is heated to 480°C, the ingot barrel is heated to 480°C, and the cast rod is heated to a lower temperature of 470°C. During extrusion, the extrusion rod push speed is controlled at 4.5mm / s, and the extrusion outlet temperature is about 470°C. After the extruded profile comes out, it is quenched online by strong wind cooling to reduce the temperature to below 200°C. The extruded profile is stretched and straightened, and the stretching rate is controlled below 0.5%.

[0130] Experimental Example 5.2 adopts the following extrusion process: the mold is heated to 480℃, the ingot barrel is heated to 480℃, and the cast rod is heated to a higher temperature of 540℃. During extrusion, the extrusion rod push speed is controlled at 4.5mm / s, and the extrusion outlet temperature is about 540℃. After the extruded profile comes out, it is quenched online by strong wind cooling to reduce the temperature to below 200℃. The extruded profile is stretched and straightened, and the stretching rate is controlled below 0.5%.

[0131] The same test method as in Experimental Example 0 was used to test the yield strength, tensile strength, elongation and hardness of the material. The test results are shown in Table 13.

[0132] Table 13

[0133]

[0134] Through comparative experiments, it can be seen that extrusion temperature is a key factor affecting the performance of aluminum alloy materials with the composition of the present invention. The experimental results show that appropriately increasing the extrusion temperature is beneficial to improving material properties. The tensile strength of Experimental Example 0 (510°C) is 382MPa, while the tensile strength of Experimental Example 5.1 at a lower temperature (470°C) is significantly reduced to 321MPa, and the tensile strength of Experimental Example 5.2 at a higher temperature (540°C) is slightly increased to 385MPa, but the elongation is reduced. This shows that lower temperatures will lead to decreased material fluidity and insufficient grain refinement, thereby significantly reducing mechanical properties, while appropriately increasing the temperature is beneficial to improving material fluidity and promoting grain homogenization, but too high a temperature may affect the elongation. Therefore, in the case of low Si, low Mg or low Cu content, the mechanical properties can be improved by appropriately increasing the extrusion temperature.

[0135] Experimental Example 6

[0136] The element content, casting process, homogenization process, and aging process of this experimental example are the same as those of Experimental Example 0, and the difference lies in the extrusion process.

[0137] This experimental example adopts the following extrusion process: the die is heated to 480℃, the ingot barrel is heated to 480℃, and the cast rod is heated to 510℃. During extrusion, the extrusion rod push speed is controlled at 4.5mm / s, and the extrusion outlet temperature is about 510℃. After the extruded profile comes out, it is quenched online by strong wind cooling to reduce the temperature to below 200℃. The extruded profile is stretched and straightened, and the stretching rate is controlled below 0.5%.

[0138] The same test method as in Experimental Example 0 was used to test the yield strength, tensile strength, elongation and hardness of the material. The test results are shown in Table 14.

[0139] Table 14

[0140]

[0141] By comparing the cooling methods of the extrusion outlet of Experimental Example 0 and Experimental Example 6, the effects of different cooling methods on the mechanical properties of the aluminum alloy after extrusion of the composition of the present invention were studied. Experimental Example 0 uses water spray cooling, while Experimental Example 6 uses strong wind cooling. The test results show that the cooling method has a significant effect on the mechanical properties of the aluminum alloy. Specifically, the yield strength of Experimental Example 0 is 345MPa, the tensile strength is 382MPa, the hardness is 124HV, and the elongation is 10.0%; while the yield strength of Experimental Example 6 is 280MPa, the tensile strength is 315MPa, the hardness is 110HV, and the elongation is 9.3%. These data show that the cooling intensity of water spray cooling is higher than that of strong wind cooling, which can more effectively inhibit the precipitation of alloy elements and grain growth, thereby improving the yield strength, tensile strength and hardness of the material. In addition, water spray cooling can also better maintain the elongation of the material. Therefore, the cooling intensity of the extrusion outlet has a key influence on the mechanical properties of the final extruded profile, and a large cooling intensity is conducive to the material to obtain better mechanical properties. Therefore, in actual production, a cooling method with stronger cooling effect (such as water spray cooling) is preferred to optimize the comprehensive performance of aluminum alloy profiles.

[0142] The above embodiments are exemplary, and their purpose is to illustrate the technical concept and features of the present invention so that people familiar with the technology in this field can understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A 6 series aluminum alloy material, characterized in that: The mass content of each element in the aluminum alloy material is as follows: Si (Silicon): 0.65% - 0.9%; Mg (Magnesium): 0.85% - 1.1%; Cu (copper): 0.5% - 0.8%; Mn (Manganese): 0.05% - 0.18%; Cr (chromium): 0.05% - 0.15%; Zn (zinc): ≤0.1%; Ti (titanium): ≤0.1%; Fe (Iron): ≤0.15%; The balance is Al (aluminum) and inevitable impurities.

2. A method for manufacturing a 6 series aluminum alloy extruded profile, characterized in that: The 6 series aluminum alloy material according to claim 1 is cast, homogenized, extruded and artificially aged to prepare a 6 series aluminum alloy extruded profile.

3. The method for manufacturing a 6 series aluminum alloy extruded profile according to claim 2, characterized in that: The following steps are involved: a) Casting: Melting and casting are carried out according to the mass percentage of each element in the aluminum alloy material to obtain cast bars; b) homogenization treatment: subjecting the cast rod to single-stage or double-stage homogenization treatment; c) Extrusion: The homogenized cast rod is heated and extruded to prepare the profile, and then quenched online after extrusion; d) Artificial aging treatment: Single-stage or double-stage artificial aging treatment is performed on the extruded profile.

4. The method for manufacturing a 6 series aluminum alloy extruded profile according to claim 3, characterized in that: The casting step comprises: a1) placing Al ingots, Mg ingots, Cu ingots, and master alloys of Al-Si and Al-Mn in a melting furnace to melt into an aluminum alloy solution; a2) Sampling the aluminum alloy solution to analyze its composition, and tempering it to within the set aluminum alloy composition range by adding metal elements; a3) Deslagging, refining and standing the aluminum alloy solution; a4) The aluminum alloy solution is introduced into a mold for casting to obtain a cast rod.

5. The method for manufacturing a 6 series aluminum alloy extruded profile according to claim 3, characterized in that: The homogenization treatment is a single-stage homogenization, including heating the cast rod to 540-580°C at a rate of 30-100°C / h, and keeping the temperature for 6-24h; after the temperature is kept, cooling the cast rod to below room temperature at a rate of 100-200°C / h.

6. The method for manufacturing a 6-series aluminum alloy extruded profile according to claim 3, characterized in that: The homogenization treatment is a two-stage homogenization, including heating the cast rod to 500-540°C at a rate of 100-200°C / h, keeping the temperature for 2-6h; then heating to 540-580°C at a rate of 100-200°C / h, keeping the temperature for 6-20h; and finally cooling to below room temperature at a rate of 100-200°C / h.

7. The method for manufacturing a 6 series aluminum alloy extruded profile according to claim 3, characterized in that: The extrusion step comprises: c1) Heat the mold and ingot tube to 430-480℃, and heat the cast rod to 495-560℃; c2) During extrusion, the extrusion rod pushing speed is controlled at 3-6mm / s, and the extrusion outlet temperature is 480-560℃; c3) After the extruded profile comes out, it is quenched online by water spray cooling to ensure that the profile temperature drops below 200°C; c4) The extruded profile can be stretched and straightened according to the accuracy requirements, and the stretching rate is controlled below 0.5%.

8. The method for manufacturing a 6 series aluminum alloy extruded profile according to claim 3, characterized in that: The artificial aging treatment is a single-stage artificial aging treatment, which includes heating the extruded aluminum alloy profile to 170-200° C., keeping the temperature for 3-18 hours, and cooling it to room temperature with strong wind after it comes out of the furnace; or the artificial aging treatment is a double-stage artificial aging treatment, which includes heating the extruded aluminum alloy profile to 100-130° C., keeping the temperature for 2-4 hours; then heating it to 160-180° C., keeping the temperature for 4-10 hours, and cooling it to room temperature with strong wind after it comes out of the furnace.

9. A 6 series aluminum alloy extruded profile, characterized in that: The extruded profile has a yield strength of 320-370 MPa, a tensile strength of 340-400 MPa, a hardness of 110-126 HV, and an elongation of 8%-14%; the extruded profile is prepared according to the manufacturing method according to any one of claims 2 to 8.

10. An application of a 6 series aluminum alloy extruded profile, characterized in that: The extruded profile is the 6-series aluminum alloy extruded profile described in claim 9, which is used to prepare offshore photovoltaic module structural parts.

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