Peak aging system merging method for aluminum alloy plates of same series and different marks

Abstract

The invention discloses a peak aging system merging method for aluminum alloy plates of the same series and different brands, which comprises the following steps: (1) selecting peak aging systems of two aluminum alloys of different brands, and the peak aging systems of the two aluminum alloys of different brands are similar; (2) according to the peak aging systems of the two different grades of aluminum alloys, determining the furnace combination aging temperature T, and calculating the theoretical furnace combination aging time t; and (3) carrying out aging temperature transfer verification according to the determined furnace closing aging temperature and the determined furnace closing aging time, and determining whether the furnace closing aging temperature and the furnace closing aging time can simultaneously ensure whether the mechanical properties of the two different brands of aluminum alloys meet the requirements or not. According to the method disclosed by the invention, the two aluminum alloys with similar peak aging systems and relatively stable performance can be subjected to furnace combination aging, so that the problem that the charging amount is very small or the furnace is assembled by waiting materials when the yield ratio of a section produced by the aluminum alloy of a certain mark is low is solved, the utilization rate of the aging furnace is improved, and the production efficiency is also improved.

Description

Technical Field

[0001] The invention relates to the technical field of aluminum alloy aging, and in particular to a method for combining peak aging systems of aluminum alloy plates of the same series but different grades. Background Art

[0002] Aluminum alloy is the most widely used type of non-ferrous metal structural material in industry, and has been widely used in aviation, aerospace, automobile, machinery manufacturing, shipbuilding and chemical industries. At present, most aluminum alloys that can be heat-treated and strengthened usually need to be heat-treated after forming to obtain good mechanical properties, physical properties and corrosion resistance. Heat treatment mainly includes solution treatment and aging. Usually, different grades of aluminum alloys adopt different aging systems. By controlling the aging system, that is, controlling the aging temperature and time, a better strengthening effect can be obtained. When different grades of aluminum alloys are produced using different aging systems, if the output of profiles produced by a certain grade of aluminum alloy is low, it is easy to have a small amount of furnace loading or equal material grouping phenomenon, which not only reduces the utilization rate of the aging furnace, but also reduces production efficiency. Based on this, the present invention proposes a peak aging system merging method for different grades of aluminum alloy plates. Summary of the invention

[0003] In order to solve the above technical problems, the present invention provides a method for merging peak aging systems of aluminum alloy plates of the same series but different grades.

[0004] The technical solution adopted by the present invention is:

[0005] The present invention provides a method for merging peak aging systems of aluminum alloy plates of the same series but different grades, comprising the steps of:

[0006] (1) Select two peak aging systems of aluminum alloys of the same series but different grades, and the peak aging systems of the two grades of aluminum alloys are similar;

[0007] (2) According to the peak aging system of two aluminum alloys of the same series but different grades, determine the combined furnace aging temperature and calculate the theoretical combined furnace aging time;

[0008] (3) Based on the determined aging temperature and aging time, an aging temperature transition verification is performed to determine whether the aging temperature and aging time can simultaneously ensure that the mechanical properties of the two different grades of aluminum alloys meet the requirements.

[0009] Furthermore, the difference in peak aging temperature between the two aluminum alloys of different grades selected in step (1) is ≤15°C, and the difference in peak aging time is ≤10h.

[0010] Furthermore, the two different grades of aluminum alloys selected in step (1) are 6061 and 6082 alloys.

[0011] Furthermore, in step (2), the aging temperature of the combined furnace is T 1 ≤T≤T 2 , where T 1 , T 2 are the peak aging temperatures of the first and second grades of aluminum alloys selected, respectively, and T 1 ≤T 2 .

[0012] Furthermore, in the step (2), when the combined furnace aging temperature is determined to be T, the required aging time t of the first and second grades of aluminum alloys selected are calculated respectively by the following formula: 1 ,t 2 ,Right now:

[0013]

[0014] Where T is the furnace aging temperature, t 1 ,t 2 are the required aging time of the first and second grades of aluminum alloys selected when the combined furnace aging temperature is T, t 1 ′ ,t 2 ′ are the aging time of the original peak aging system of the first and second grades of aluminum alloys selected, T 1 ′ , T 2 ′ They are the aging temperatures of the original peak aging systems of the first and second grades of aluminum alloys selected respectively, Q is the activation energy, the activation energy of the same series of alloys is basically the same, and C is a constant.

[0015] Furthermore, in step (2), when the combined furnace aging temperature is determined to be T, {t 1 , t 2} max As the furnace aging time.

[0016] Furthermore, in step (2), when the combined furnace aging temperature T is determined to be {T 1 , T 2} max When the determined furnace aging time t is equal to {T 1 , T 2} max The corresponding aging time difference is ≤5h.

[0017] Furthermore, the step (3) is specifically as follows:

[0018] (31) For the two selected aluminum alloys of different grades, a number of samples of different thicknesses are taken and aging is performed according to the determined aging temperature and aging time;

[0019] (32) After aging is completed and the samples are cooled to room temperature, samples are taken to test the mechanical properties of each sample;

[0020] (33) Compare the mechanical properties of each sample after furnace aging with the corresponding mechanical property standard requirements to determine whether they meet the standard requirements. If they do, it means that the furnace aging system is feasible. If they do not, the furnace aging temperature and time need to be modified and re-verified.

[0021] The beneficial effects of the present invention are:

[0022] The present invention provides a method for merging peak aging systems of aluminum alloy plates of the same series but different grades. Through the method, two aluminum alloys with similar peak aging systems and relatively stable performance can be combined for aging, thereby solving the problem of small furnace loading or equal material grouping when the output of profiles produced by a certain grade of aluminum alloy accounts for a low proportion. Not only the utilization rate of the aging furnace is improved, but also the production efficiency is improved. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0024] Figure 1 is a flow chart of the present invention;

[0025] Figure 2 This is a comparison chart of the tensile strength of the 6061 alloy in two different aging systems according to an embodiment of the present invention;

[0026] Figure 3 This is a comparison diagram of the yield strength of the 6061 alloy in two different aging systems according to an embodiment of the present invention;

[0027] Figure 4 This is a comparison chart of the elongation of the 6061 alloy in two different aging systems according to an embodiment of the present invention;

[0028] Figure 5 A comparison chart of the tensile strength of the 6082 alloy in two different aging systems according to an embodiment of the present invention;

[0029] Figure 6This is a comparison diagram of the yield strength of the 6082 alloy in two different aging systems according to an embodiment of the present invention;

[0030] Figure 7 This is a comparison chart of the elongation of the 6082 alloy of the embodiment of the present invention under two different aging systems. DETAILED DESCRIPTION

[0031] The present invention provides a method for combining peak aging systems of aluminum alloy plates of the same series but different grades. In order to make the purpose, technical solution and effect of the present invention clearer and more specific, the present invention is further described in detail below. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0032] Reference Figure 1 In this embodiment, 6061 alloy and 6082 alloy are taken as examples to explain in detail the method for combining the peak aging systems of aluminum alloy plates of the same series but different grades according to the present invention.

[0033] First, by studying and analyzing the artificial aging systems and mechanical properties of 6061 and 6082 alloys of the same series but different grades, it was found that the peak aging systems of these two alloys are similar and the mechanical properties are relatively stable over time, with a large room for adjustment, and there is a possibility of merging the peak aging systems of the two alloys.

[0034] It should be noted that the combined furnace aging in this embodiment is for peak aging, i.e., T6 state. This is because the T6 peak aging state is a relatively stable state, unlike the T7 state which is easily affected by the holding time. If a large amount of holding time is not increased or aging is performed at a higher level of temperature, the performance will not fluctuate too much and will be relatively stable.

[0035] According to the actual production situation, the peak aging degree of 6061 and 6082 alloy plates is determined, as shown in Table 1 below.

[0036] Table 1 Original peak aging system

[0037]

[0038] Note: T651 state means that after solution treatment and quenching, the product is stretched a certain amount to eliminate stress (the permanent deformation of thin plates is 0.5% to 3.0%; the permanent deformation of thick plates is 1.5 to 3.0%), and then artificially aged. After stretching, the product is no longer further straightened.

[0039] Secondly, according to the peak aging system of two different grades of aluminum alloys, the combined furnace aging temperature is determined, and the theoretical combined furnace aging time is calculated; specifically, the combined furnace temperature satisfies T 1 ≤T≤T 2When the combined furnace aging temperature is determined to be T, the required aging time t of the first and second grades of aluminum alloys selected is calculated by the following formula: 1 ,t 2 ,Right now:

[0040]

[0041] Then select {t 1 , t 2} max As the furnace aging time.

[0042] In this embodiment, the peak aging temperature of 165°C of the 6082 alloy is used as the combined furnace aging temperature. At this time, the aging time required for 6082 does not need to be calculated and remains at 16 hours. Then, when the aging temperature is 165°C, the aging time required for the 6061 alloy is calculated to be 18.06 hours. That is, under theoretical conditions, the aging temperature of the 6061 alloy is increased to 165°C and kept warm for 18 hours to achieve the strength of the original aging system.

[0043] Compared with the aging system of 6061 calculated above (165℃*18h), the aging system of 6082 (165℃*16h) needs to extend the aging holding time by 2h. For the T6 state, the mechanical properties fluctuate less theoretically after extending it by 2h. Therefore, the peak aging systems of 6061 and 6082 alloy plates can be combined to obtain the combined furnace aging system, as shown in Table 2 below.

[0044] Table 2 Furnace aging system

[0045]

[0046] Third, according to the above-determined aging temperature and aging time, the aging temperature transition verification is carried out to determine whether the aging temperature and aging time can simultaneously ensure that the mechanical properties of the two different grades of aluminum alloys meet the requirements. Specifically:

[0047] (31) For the selected two different grades of aluminum alloy 6061 and 6082, several specimens of different thicknesses were taken and divided into two groups, one of which was aged according to the original peak aging system, and the other was aged according to the determined combined aging temperature and combined aging time;

[0048] (32) After aging is completed and the samples are cooled to room temperature, samples are taken to test the mechanical properties of each sample;

[0049] (33) Compare the mechanical properties of the two groups of samples, analyze the trend of mechanical property changes, and compare the mechanical properties of the combined furnace aging with the corresponding mechanical property standard requirements to determine whether they meet the standard requirements. If they do, it means that the combined furnace aging system is feasible. If they do not, the combined furnace aging temperature and time need to be modified and re-verified.

[0050] In this embodiment, several samples with a thickness of 10 to 90 mm were prepared from 6061 sheet materials. The mechanical properties before and after the aging system was adjusted were as follows: Figure 2-4 As shown in the figure, several specimens with a thickness of 20 to 70 mm were prepared for 6082 plates. The mechanical properties before and after the aging system was adjusted are shown in the figure. Figure 5-7 shown.

[0051] from Figure 2-4 It can be seen that for 6061 alloy, when aged at 165℃*18h, its mechanical properties are not much different from those at 162℃*24h, both of which can meet the standard requirements. In addition, compared with the mechanical properties under the original aging system, the difference is small, or even improved. In addition, compared with the standard requirements, the tensile strength is about 20MPa greater than the standard value, the yield strength is about 20MPa greater than the standard value, and the elongation is about 5.5% greater than the standard value, all of which meet the standard requirements.

[0052] from Figure 5-7 It can be seen that for 6082 alloy, when aged at 165℃*18h, its mechanical properties are not much different from those at 165℃*16h, with small fluctuations, and both can meet the standard requirements. In addition, compared with the mechanical properties under the original aging system, the difference is small. In addition, compared with the standard requirements, the tensile strength is about 15MPa greater than the standard value, the yield strength is about 30MPa greater than the standard value, and the elongation is about 3% greater than the standard value, all meeting the standard requirements.

[0053] It has been verified that the peak aging systems of 6061 and 6082 alloys can be combined, and the combined aging system meets the mechanical property standard requirements of the two alloys. Combining the T6 state aging systems of 6061 alloy and 6082 alloy can greatly improve production efficiency and increase the utilization rate of aging furnaces.

[0054] It should be noted that some parts not described in the present invention can be implemented by adopting or drawing on existing technologies.

[0055] Of course, the above description is not a limitation of the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions or substitutions made by technicians in this technical field within the essential scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. A method for combining peak aging systems of aluminum alloy plates of the same series but different grades, characterized in that: Includes steps: (1) Select two peak aging systems of aluminum alloys of the same series but different grades, and the peak aging systems of the two grades of aluminum alloys are similar; (2) According to the peak aging system of two aluminum alloys of the same series but different grades, the combined furnace aging temperature T is determined, and the theoretical combined furnace aging time t is calculated; (3) Based on the determined aging temperature and aging time, an aging temperature transition verification is performed to determine whether the aging temperature and aging time can simultaneously ensure that the mechanical properties of the two different grades of aluminum alloys meet the requirements.

2. The method for combining peak aging systems of aluminum alloy plates of the same series but different grades according to claim 1, characterized in that: The difference in peak aging temperature between the two aluminum alloys of the same series but different grades selected in the step (1) is ≤15°C, and the difference in peak aging time is ≤10h.

3. The method for combining peak aging systems of aluminum alloy plates of the same series but different grades according to claim 1, characterized in that: In the step (2), the aging temperature of the combined furnace is T1≤T≤T2, wherein T1 and T2 are the peak aging temperatures of the first and second grades of the selected aluminum alloys, respectively, and T1≤T2.

4. The method for combining peak aging systems of aluminum alloy plates of the same series but different grades according to claim 1, characterized in that: In the step (2), when the combined furnace aging temperature is determined to be T, the required aging times t1 and t2 of the first and second grades of aluminum alloys are calculated respectively by the following formulas, namely: Where T is the combined furnace aging temperature, t1 and t2 are the required aging time of the first and second grades of aluminum alloy selected when the combined furnace aging temperature is T, t1 ′ , t2 ′ are the aging time of the original peak aging system of the first and second grades of aluminum alloys selected, T1 ′ 、T2 ′ are the aging temperatures of the original peak aging systems of the first and second grades of aluminum alloys selected respectively, Q is the activation energy, and C is a constant.

5. The method for combining peak aging systems of aluminum alloy plates of the same series but different grades according to claim 4, characterized in that: In step (2), when the combined furnace aging temperature is determined to be T, select {t1, t2} max As the furnace aging time t.

6. The method for combining peak aging systems of aluminum alloy plates of the same series but different grades according to claim 4, characterized in that: In step (2), when the combined furnace aging temperature T is determined to be {T1, T2} max When the determined furnace aging time t is equal to {T1, T2} max The corresponding aging time difference is ≤5h.

7. The method for combining peak aging systems of aluminum alloy plates of the same series but different grades according to claim 1, characterized in that: The step (3) is specifically: (31) For the two selected aluminum alloys of different grades, a number of samples of different thicknesses are taken and aging is performed according to the determined aging temperature and aging time; (32) After aging is completed and the samples are cooled to room temperature, samples are taken to test the mechanical properties of each sample; (33) Compare the mechanical properties of each sample after furnace aging with the corresponding mechanical property standard requirements to determine whether they meet the standard requirements. If they do, it means that the furnace aging system is feasible. If they do not, the furnace aging temperature and time need to be modified and re-verified.

Images