TWI853724B - Method of forming aluminum alloy - Google Patents

Abstract

An age forming method for automotive parts of 6XXX and 7XXX aluminum alloys is provided. The automotive 6XXX and 7XXX aluminum alloys processed by this invention can reach excellent mechanical properties after forming and paint baking. This invention includes a pre-aging process and an age forming of 6XXX and 7XXX aluminum alloys. The aluminum alloys show following characteristics: Yield strength of the alloy after pre-aging is lower than 90% of yield strength at peak aging; yield strength of the alloy after age forming is not lower than yield strength after pre-aging. After the processes above, yield strength of the 6XXX and 7XXX aluminum alloys after natural aging and paint baking is not lower than yield strength after age forming.

Description

Manufacturing method of aluminum alloy

The present invention relates to an aluminum alloy and a method for manufacturing the same, and in particular to an aluminum alloy that can be used as a vehicle component and a method for manufacturing the same.

In recent years, due to the rising awareness of energy conservation and carbon reduction, one of the main development strategies for fuel vehicles and electric vehicles is lightweighting. Therefore, the application of lightweight metal materials in vehicle body structures has increased year by year. According to non-patent reference [1], high-strength aluminum alloys are the most important lightweight materials for vehicle bodies today. It is known that high-strength aluminum alloys are produced by peak aging (T6) heat treatment. However, peak aging heat treatment will cause the ductility of aluminum alloys to decrease as the strength increases, and at the same time affect the cold formability of aluminum alloys, thereby causing cracks in formed parts. In addition, the formed aluminum alloy automotive parts must also undergo paint baking treatment, and the paint baking treatment will reduce the strength of the aforementioned aluminum alloy, which is not conducive to its application as automotive parts.

According to non-patent reference [2], warm forming is a process that increases the forming temperature in exchange for the formability of aluminum alloys. In addition, the strength of the material is lower during warm forming, so its rebound is lower. Therefore, warm forming is a new forming technology for high-strength aluminum alloys for automobiles. According to non-patent reference [3], the temperature of warm forming is generally between 150℃ and 300℃. Too low a forming temperature cannot improve ductility, while too high a forming temperature will cause a significant decrease in strength due to excessive solid solution of precipitates.

The prior art with patent publication number WO2017062403A1 discloses warm forming process parameters so that the 6XXX aluminum alloy after forming can achieve a tensile strength of 200MPa to 275MPa. However, this technology cannot take into account the effects of paint baking. The current main warm forming process for automotive aluminum alloys must be performed at an appropriate temperature. During forming, the precipitates will only be partially dissolved. After natural aging, they will be precipitated and strengthened during subsequent paint baking to compensate for the strength loss. In fact, according to the non-patent reference [4], such a process is to achieve regression and re-aging forming (RRA Forming) by combining warm forming and paint baking. In recent literature (e.g., non-patent reference [3]), by selecting appropriate forming temperature parameters in the pre-aging treatment of 7075 aluminum alloy, its yield strength can reach 95% of that of peak aging, which is the most successful case reported so far. However, in actual cases, most 6XXX and 7XXX aluminum alloys treated with RRA cannot achieve the high yield strength of T6 peak aging, which is at a disadvantage in the highly competitive automotive metal material market. Therefore, there is still a bottleneck for the large-scale application of aluminum alloy warm forming technology.

In addition, another known technology with patent publication number WO2010032002A1 replaces warm forming with hot forming, and performs aging heat treatment after hot forming to make the aluminum alloy reach the target strength. This method can avoid the softening problem caused by paint baking, and hot forming has advantages over warm forming in terms of ductility and rebound of aluminum alloy forming. However, the hot forming temperature needs to reach above the solid solution temperature of aluminum alloy precipitates, and the high temperature process causes higher energy loss and increases costs. In addition, the parts after hot forming need to undergo a longer aging heat treatment to achieve high strength, while warm forming or RRA forming generally does not require post-forming heat treatment.

From the above research on warm forming and hot forming of the 6XXX series and 7XXX series of prior art, we can know that there is currently no warm forming technology for automotive high-strength aluminum alloys based on age forming. In addition, there is no prior art involving the serial application of pre-aging and age forming, nor is there any prior art integrating the strengthening effect and feasibility of paint baking in warm forming technology.

In view of this, it is urgent to provide an aluminum alloy and a manufacturing method thereof, so as to produce an aluminum alloy with high strength and formability while saving energy and cost.

Non-patent references

Non-patent references [1]: W. Miller, L. Zhuang, J. Bottema, A.J. Wittebrood, P. De Sment, A. Haszler, A. Vieregge, Recent development in aluminum alloys for the automotive industry, Materials Science and Engineering: A 280(1)(2000) p. 37-49.

Non-patent reference [2]: K. Zheng, D. J. Politis, L. Wang, J. Lin, Areviewon forming techniques for manufacturing lightweight complex-shaped aluminum panel components, International Journal of Lightweight Materials and Manufacture 1(2)(2018) p.55-80.

Non-patent references [3]: J. A. Österreicher, M.A. Tunes, F. Grabner, A. Arnoldt, T. Kremmer, S. Pogatscher, C.M. Schlögl, Warm-forming of pre-aged Al-Zn-Mg-Cu alloy sheet, Materials & Design 193(2020) 108837.

Non-patent reference [4]: T.A. Ivanoff, Retrogression-reaging and hot forming of AA 7075, 2014.

One aspect of the present invention is to provide a method for manufacturing an aluminum alloy, which is to perform pre-aging treatment, aging forming treatment and paint baking treatment on the aluminum alloy material to obtain a high-strength aluminum alloy.

Another aspect of the present invention is to provide an aluminum alloy, which is prepared using the method of the above aspect.

Another aspect of the present invention is to provide a vehicle component, which comprises the aluminum alloy of the above aspect.

According to one aspect of the present invention, a method for manufacturing an aluminum alloy is provided. The method comprises providing an aluminum alloy material, wherein the aluminum alloy material is a 6XXX series aluminum alloy or a 7XXX series aluminum alloy; performing a pre-aging treatment on the aluminum alloy material to obtain a pre-aged aluminum alloy; performing an aging forming treatment on the pre-aged aluminum alloy to obtain an aged formed aluminum alloy; and performing a paint baking treatment on the aged formed aluminum alloy to obtain an aluminum alloy. The yield strength of the pre-aged aluminum alloy is the pre-aging strength; the yield strength of the aged formed aluminum alloy is the aged forming strength, and the aged forming strength is not less than the pre-aging strength; the yield strength of the aluminum alloy is not less than the aged forming strength.

According to one embodiment of the present invention, the above method further includes performing a solid solution heat treatment on the aluminum alloy raw material to obtain an aluminum alloy material.

According to one embodiment of the present invention, the above-mentioned pre-aging strength is less than 90% of the peak aging strength.

According to one embodiment of the present invention, the temperature of the above-mentioned pre-aging treatment is the same as the temperature of the spike aging (T6) treatment, and the time of the pre-aging treatment is 1/48 to 1/12 times the time of the spike aging (T6) treatment.

According to one embodiment of the present invention, the temperature of the aging forming treatment is 180°C to 280°C.

According to one embodiment of the present invention, the above method further includes performing a natural aging treatment on the aged formed aluminum alloy before performing the paint baking treatment, wherein the natural aging treatment includes storage at room temperature for at least one week.

According to one embodiment of the present invention, the above-mentioned aging formed aluminum alloy does not undergo an aging heat treatment.

According to another aspect of the present invention, an aluminum alloy is provided, which is prepared using the method of the above aspect.

According to another aspect of the present invention, a vehicle component is provided, which comprises the aluminum alloy of the above aspect.

The aluminum alloy manufacturing method of the present invention is applied to combine pre-aging treatment and aging forming treatment, so that the strength of the aluminum alloy is gradually increased during the forming process, and after the paint baking treatment, an aluminum alloy with high strength suitable for automotive parts is obtained.

100:Methods

110,120,130,140: Operation

The following detailed description and accompanying drawings will provide a better understanding of the present disclosure. It should be noted that, as is standard practice in the industry, many features are not drawn to scale. In fact, for the sake of clarity of discussion, the dimensions of many features may be arbitrarily scaled.

[Figure 1] is a flow chart showing a method for manufacturing an aluminum alloy according to some embodiments of the present invention.

As used in the present invention, "around", "about", "approximately" or "substantially" generally means within 20%, within 10%, or within 5% of the value or range described.

As mentioned above, the present invention provides a method for manufacturing aluminum alloy, which combines pre-aging treatment and aging forming treatment to gradually increase the strength of the aluminum alloy during the forming process, and after the painting and baking treatment, obtain an aluminum alloy with high strength suitable for automotive parts. This method greatly shortens the process time, and still obtains an aluminum alloy with high strength, so it can effectively reduce the process cost and achieve the benefits of energy saving and carbon reduction.

Please refer to FIG. 1, which is a flow chart of a method 100 for manufacturing an aluminum alloy according to some embodiments of the present invention. First, operation 110 is performed to provide an aluminum alloy material. In some embodiments, the aluminum alloy material is prepared by solution heat treating an aluminum alloy raw material. In some embodiments, the aluminum alloy material (or aluminum alloy raw material) may be a 6XXX series aluminum alloy or a 7XXX series aluminum alloy. In other embodiments, the aluminum alloy material may be an aluminum alloy rod, an aluminum alloy plate, an aluminum alloy coil, or an aluminum alloy product produced by other aluminum alloy manufacturers.

6XXX series aluminum alloys are also called aluminum-magnesium-silicon series (Al-Mg-Si) aluminum alloys, such as 6111 aluminum alloy and 6016 aluminum alloy. For example, 6111 aluminum alloy contains 0.6wt% to 1.1wt% silicon, less than 0.4wt% iron, 0.5wt% to 0.9wt% copper, 0.1wt% to 0.45wt% manganese, 0.5wt% to 1.0wt% magnesium, less than 0.1wt% chromium, less than 0.1wt% titanium, and the balance of aluminum; while 6016 aluminum alloy contains 1.0wt% to 1.5wt% silicon, less than 0.5wt% iron, less than 0.2wt% copper, less than 0.2wt% manganese, 0.25wt% to 0.6wt% magnesium, less than 0.1wt% chromium, less than 0.15wt% titanium, and the balance of aluminum. Furthermore, 7XXX series aluminum alloys are also called aluminum-zinc-magnesium-copper series (Al-Zn-Mg-Cu) aluminum alloys, such as 7075 aluminum alloy. For example, 7075 aluminum alloy contains less than 0.4wt% silicon, less than 0.5wt% iron, 1.2wt% to 2.0wt% copper, less than 0.3wt% manganese, 2.1wt% to 2.9wt% magnesium, 0.18wt% to 0.28wt% chromium, 5.1wt% to 6.1wt% zinc, less than 0.2wt% titanium, less than 0.05wt% zirconium and the balance of aluminum.

Next, operation 120 is performed to pre-age the aluminum alloy material to obtain a pre-aged aluminum alloy. In some embodiments, the temperature of the pre-aging treatment is approximately the same as the temperature of the spike aging (T6) treatment, and the time of the pre-aging treatment is about 1/48 to about 1/12 of the time of the spike aging treatment. It should be understood that the temperature and time of the spike aging treatment vary according to different material compositions. For example, the spike aging treatment of 6XXX series aluminum alloys may be performed at a temperature of about 180°C for about 8 hours to about 10 hours, or at a temperature of about 160°C for about 16 hours to about 20 hours; and the spike aging treatment of 7XXX series aluminum alloys may be performed at a temperature of about 120°C for about 24 hours.

The pre-aged aluminum alloy produced by operation 120 has a pre-aging strength, and the pre-aging strength is less than about 90% of the peak aging strength. In some embodiments where the aluminum alloy is a 6XXX series aluminum alloy, the pre-aging strength of the pre-aged aluminum alloy is about 50% to about 90% of the peak aging strength. In some embodiments where the aluminum alloy is a 7XXX series aluminum alloy, the pre-aging strength of the pre-aged aluminum alloy is about 50% to about 90% of the peak aging strength. It should be understood that the pre-aging strength refers to the yield strength of the aluminum alloy after the pre-aging treatment, and the peak aging strength refers to the yield strength of the aluminum alloy after the peak aging treatment.

Next, operation 130 is performed to perform an aging forming treatment on the pre-aged aluminum alloy to obtain an aged formed aluminum alloy. In some embodiments, the temperature of the aging forming treatment is about 180°C to about 280°C. If the temperature of the aging forming treatment is too low (e.g., less than about 180°C), the ductility of the aluminum alloy cannot be effectively improved; if the temperature of the aging forming treatment is too high (e.g., greater than about 280°C), the strength of the aluminum alloy cannot be effectively improved during the aging forming process. The aged formed aluminum alloy obtained by operation 130 has an aging forming strength, and the aging forming strength is greater than the pre-aging strength. The aged formed aluminum alloy that has undergone the aging forming treatment does not need to undergo an aging heat treatment. It should be understood that the aging forming strength refers to the yield strength of the aluminum alloy after the aging forming treatment.

Then, operation 140 is performed to perform a paint baking treatment on the aged formed aluminum alloy to obtain an aluminum alloy. In some embodiments, the paint baking treatment includes holding the temperature at 185°C for 20 minutes. The strength of the aluminum alloy obtained by operation 140 is greater than the aging forming strength. In some embodiments, before operation 140, the aged formed aluminum alloy is subjected to a natural aging treatment. The natural aging treatment includes storage at room temperature for at least one week.

Method 100 performs artificial aging treatment on the aluminum alloy after solution treatment by pre-aging treatment. The strength of the obtained pre-aged aluminum alloy does not reach the strength after peak aging treatment, which means that the aluminum alloy can continue to precipitate strengthening phases in the subsequent aging forming treatment. Therefore, the aged formed aluminum alloy obtained after the aging forming treatment has higher strength than the pre-aged aluminum alloy. Then, the aluminum alloy obtained after the paint baking treatment can further improve the strength. Therefore, method 100 can produce an aluminum alloy with higher strength, and at the same time shorten the time spent in the process, reduce energy consumption and process costs.

Several embodiments are used below to illustrate the application of the present invention, but they are not intended to limit the present invention. People with ordinary knowledge in the technical field of the present invention can make various changes and modifications without departing from the spirit and scope of the present invention.

Implementation Example 1

Embodiment 1 is to perform a forming process on the AA6111 aluminum alloy after solution heat treatment, wherein the composition of the AA6111 aluminum alloy includes 0.6wt% to 1.1wt% silicon, less than 0.4wt% iron, 0.5wt% to 0.9wt% copper, 0.1wt% to 0.45wt% manganese, 0.5wt% to 1.0wt% magnesium, less than 0.1wt% chromium, less than 0.1wt% titanium and a balance of aluminum. The peak aging treatment condition of the AA6111 aluminum alloy is 180℃ for 480 minutes.

In Example 1, the AA6111 aluminum alloy material is first subjected to a pre-aging treatment at 180°C for 10 minutes; then, an aging forming treatment is performed at 250°C for 2 minutes; then, after natural aging for 1 week, a paint baking treatment is performed at 185°C for 20 minutes to obtain the aluminum alloy of Example 1. The yield strength, tensile strength and elongation of the aluminum alloy of Example 1 at each stage of the manufacturing process are shown in Table 1.

Comparison Examples 1 to 3

Comparative Examples 1 to 3 use the same AA6111 aluminum alloy as Example 1 and perform a similar process as Example 1. The difference between Comparative Examples 1 to 3 and Example 1 is that Comparative Example 1 first performs a peak aging treatment at 180°C for 480 minutes on the AA6111 aluminum alloy material; Comparative Example 2 first performs a pre-aging treatment at 180°C for 60 minutes on the AA6111 aluminum alloy material, and adjusts the aging forming treatment temperature to 200°C; and Comparative Example 3 increases the aging forming treatment temperature to 300°C. The yield strength, tensile strength and elongation of the aluminum alloys of Comparative Examples 1 to 3 at each stage of the process are shown in Table 1.

Table 1

As shown in Table 1, the yield strength of the aluminum alloy of Example 1 after pre-aging treatment is only 181MPa, and the tensile strength is only 298MPa, which is lower than the yield strength (334MPa) and tensile strength (398MPa) of Comparative Example 1 after spike aging treatment. The yield strength of the aluminum alloy of Example 1 after aging forming treatment is increased to 261MPa, and the tensile strength is increased to 312MPa; after natural aging and paint baking treatment, the yield strength is further increased to 297MPa, and the tensile strength is increased to 355MPa.

The aluminum alloy of Comparative Example 1 has a yield strength of 334MPa and a tensile strength of 398MPa after peak aging treatment, but after aging forming treatment, the yield strength drops to 289MPa and the tensile strength drops to 348MPa; after natural aging and paint baking treatment, the yield strength rises back to 302MPa and the tensile strength rises back to 356MPa. The process of Comparative Example 1 is a Retrogression and Re-Aging Forming (RRA Forming) process.

The aluminum alloy in Comparative Example 2 extends the pre-aging time, so the yield strength after pre-aging is 271MPa, and the tensile strength is 338MPa; but after aging forming treatment, the yield strength drops to 254MPa, and the tensile strength drops to 314MPa; after natural aging and paint baking treatment, the yield strength rises back to 278MPa, and the tensile strength rises back to 345MPa. Therefore, Comparative Example 2 is also an RRA forming process, but the performance is poor.

In comparison example 3, after aging treatment at a relatively high temperature of 300°C, the yield strength increased to 257MPa, and the tensile strength remained at 298MPa; after natural aging and paint baking treatment, the yield strength only increased to 268MPa, and the tensile strength only increased to 304MPa. It can be seen that the relatively high temperature aging treatment cannot effectively improve the strength of aluminum alloys.

The main precipitation strengthening phase of AA6111 aluminum alloy is the rod-shaped β” phase, and the long axis direction of the rod-shaped precipitation phase is the <001> direction of the face-centered cubic aluminum matrix. Therefore, in the transmission electron microscope, when analyzing in the <001> direction of the aluminum matrix, two groups of vertical thin strip precipitation phases and one group of granular precipitation can be observed in the projection, all of which are rod-shaped β” phases. From the results of Example 1 and Comparative Example 1, it can be understood that the precipitates generated by the aging forming process of Example 1 and the RRA forming process of Comparative Example 1 are both rod-shaped β" phases, and the density of the precipitated phases of the two is similar, so the precipitation strengthening contribution ratio is similar. Therefore, the performance of the aluminum alloys of Example 1 and Comparative Example 1 is similar. Although the strength of the aluminum alloy of Example 1 is not higher than that of the aluminum alloy of Comparative Example 1, replacing the peak aging treatment with pre-aging treatment can shorten the time of this stage by about 48 times.

Implementation Example 2

Embodiment 2 is to perform a forming process on the AA7075 aluminum alloy after solution heat treatment, wherein the composition of the AA7075 aluminum alloy includes less than 0.4wt% silicon, less than 0.5wt% iron, 1.2wt% to 2.0wt% copper, less than 0.3wt% manganese, 2.1wt% to 2.9wt% magnesium, 0.18wt% to 0.28wt% chromium, 5.1wt% to 6.1wt% zinc, less than 0.2wt% titanium, less than 0.05wt% zirconium and a balance of aluminum. The peak aging treatment condition of the AA7075 aluminum alloy is 120℃ for 24 hours.

In Example 2, the AA7075 aluminum alloy material is first subjected to a pre-aging treatment at 120°C for 2 hours; then, an aging forming treatment is performed at 225°C for 2 minutes; then, after natural aging for 1 week, a paint baking treatment is performed at 185°C for 20 minutes to obtain the aluminum alloy of Example 2. The yield strength, tensile strength and elongation of the aluminum alloy of Example 2 at each stage of the manufacturing process are shown in Table 2.

Comparison Examples 4 and 5

Comparative Examples 4 and 5 use the same AA7075 aluminum alloy as Example 2 and perform a similar process as Example 2. The difference between Comparative Examples 4 and 5 and Example 2 is that Comparative Example 4 first performs a peak aging treatment at 120°C for 24 hours on the AA7075 aluminum alloy material; while Comparative Example 5 increases the temperature of the aging forming treatment to 300°C. The yield strength, tensile strength and elongation of the aluminum alloys of Comparative Examples 4 and 5 at each stage of the process are shown in Table 2.

Table 2

As shown in Table 2, the yield strength of the aluminum alloy of Example 2 after pre-aging treatment is only 291MPa, and the tensile strength is only 551MPa, which is lower than the yield strength (439MPa) and tensile strength (576MPa) of Comparative Example 4 after peak aging treatment. The yield strength of the aluminum alloy of Example 2 after aging forming treatment is increased to 389MPa, and the tensile strength is increased to 563MPa; after natural aging and paint baking treatment, the yield strength is further increased to 482MPa, and the tensile strength is increased to 627MPa.

The aluminum alloy of Comparative Example 4 has a yield strength of 439MPa and a tensile strength of 576MPa after peak aging treatment, but after aging forming treatment, the yield strength drops to 406MPa and the tensile strength drops to 541MPa; after natural aging and paint baking treatment, the yield strength rises to 466MPa and the tensile strength rises to 572MPa. The process of Comparative Example 4 is RRA forming process.

After the comparative example 5 was subjected to aging forming treatment at a relatively high temperature of 300℃, its yield strength dropped to 257MPa, and its tensile strength dropped to 418MPa; after natural aging and paint baking treatment, its yield strength recovered to 279MPa, and its tensile strength recovered to 503MPa. It can be seen that the relatively high temperature aging forming treatment cannot effectively improve the strength of aluminum alloy.

The main precipitation strengthening phase of AA7075 aluminum alloy is η' phase, whose size is no more than 10nm, and the coarse lamellar η phase (size is more than 10nm) should be avoided as much as possible. However, according to the detection results of transmission electron microscope, the precipitation strengthening phase of Example 2 after pre-aging treatment is mainly η' phase and GP zone, whose density is low and size is small, but the strengthening effect of GP zone is poor. After aging forming treatment, the precipitation strengthening phase is mainly η' phase and η phase, whose density is high and size is slightly larger. Although GP zone still exists, it can provide better precipitation strengthening effect. Finally, after natural aging and paint baking, the precipitated strengthening phases are mainly η’ phase and η phase, and their density reaches the highest, and there is almost no GP zone, so the aluminum alloy can have higher strength.

In comparison, although the precipitates generated in Example 4 also contain both η' phase and η phase, Example 4 contains more coarse η phase, so the precipitation strengthening effect of Example 4 is poor. In addition, the precipitation strengthening phases of Example 4 after spike aging treatment include η' phase, η phase and GP zone, among which the existence of GP zone means that the η' phase is not fully generated, and the precipitation strengthening effect of GP zone is not as good as that of η' phase, so the precipitation strengthening effect of spike aging in Example 4 is slightly lower than that in Example 2. Therefore, the strength of the aluminum alloy in Example 2 is indeed slightly higher than that in Example 4, and the use of pre-aging treatment instead of spike aging treatment in Example 2 can shorten the time of this stage by about 12 times.

Implementation Example 3

Embodiment 3 is to perform a forming process on the AA6016 aluminum alloy after solution heat treatment, wherein the composition of the AA6111 aluminum alloy includes 1.0wt% to 1.5wt% silicon, less than 0.5wt% iron, less than 0.2wt% copper, less than 0.2wt% manganese, 0.25wt% to 0.6wt% magnesium, less than 0.1wt% chromium, less than 0.15wt% titanium and a balance of aluminum.

In Example 3, the AA6016 aluminum alloy material is first subjected to a pre-aging treatment at 180°C for 10 minutes; then, an aging forming treatment is performed at 200°C for 2 minutes; then, after natural aging for 1 week, a paint baking treatment is performed at 185°C for 20 minutes to obtain the aluminum alloy of Example 3. The yield strength, tensile strength and elongation of the aluminum alloy of Example 3 at each stage of the manufacturing process are shown in Table 3.

As shown in Table 3, the yield strength of the aluminum alloy of Example 3 after pre-aging treatment is only 137MPa, and the tensile strength is only 230MPa; then, after aging forming treatment, the yield strength is increased to 161MPa, and the tensile strength is increased to 246MPa; after natural aging and paint baking treatment, the yield strength is further increased to 216MPa, and the tensile strength is increased to 279MPa.

According to the above-mentioned embodiments, the present invention combines pre-aging treatment and aging forming treatment, so that the aluminum alloy can continuously precipitate strengthening phases during the forming process, so that the strength gradually increases, and after the painting and baking treatment, an aluminum alloy with high strength suitable for automotive parts is obtained. In this way, an aluminum alloy with high strength can be produced in a shorter process time, so the process cost and energy consumption can be saved.

Although the present invention has been disclosed as above with several embodiments, they are not intended to limit the present invention. Anyone with ordinary knowledge in the technical field to which the present invention belongs can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope of the patent application attached hereto.

100:Methods

110,120,130,140: Operation

Claims (6)

A method for manufacturing an aluminum alloy comprises: providing an aluminum alloy material, wherein the aluminum alloy material is a 6XXX series aluminum alloy or a 7XXX series aluminum alloy; performing a pre-aging treatment on the aluminum alloy material to obtain a pre-aged aluminum alloy, wherein the yield strength of the pre-aged aluminum alloy is a pre-aging strength, the temperature of the pre-aging treatment is the same as the temperature of a spike aging (T6) treatment, and the time of the pre-aging treatment is the peak aging (T6) treatment. 6) 1/48 to 1/12 of the treatment time; performing an aging forming treatment on the pre-aged aluminum alloy to obtain an aging formed aluminum alloy, wherein the yield strength of the aging formed aluminum alloy is an aging forming strength, and the aging forming strength is not less than the pre-aging strength; and performing a paint baking treatment on the aging formed aluminum alloy to obtain the aluminum alloy, wherein a yield strength of the aluminum alloy is not less than the aging forming strength. The method for manufacturing the aluminum alloy as described in claim 1 further comprises: performing a solid solution heat treatment on an aluminum alloy raw material to obtain the aluminum alloy material. A method for manufacturing an aluminum alloy as described in claim 1, wherein the pre-aging strength is less than 90% of a peak aging strength. The method for manufacturing an aluminum alloy as described in claim 1, wherein the temperature of the aging forming treatment is 180°C to 280°C. The method for manufacturing the aluminum alloy as described in claim 1 further comprises: before the paint baking treatment, the aged formed aluminum alloy is subjected to a natural aging treatment, wherein the natural aging treatment comprises storage at room temperature for at least one week. A method for manufacturing an aluminum alloy as described in claim 1, wherein the aged formed aluminum alloy does not undergo an aging heat treatment.

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