A method of heat treating an aluminum alloy

Abstract

The application provides an aluminum alloy heat treatment method, comprising the following steps: solution treatment: solution treating T6 state aluminum alloy rolling plate at 520 DEG C for 1h, and water cooling to normal temperature; pre-aging treatment: pre-aging treating the plate after solution treatment at 90 DEG C for 1h, and air cooling to room temperature to obtain the plate after pre-aging treatment; artificial aging treatment: artificial aging treating the plate after pre-aging treatment at 175 DEG C for 4h-12h, and air cooling to room temperature. The aluminum alloy heat treatment method of the application firstly solution treats T6 state aluminum alloy rolling plate, pre-ages treats the plate, obtains the aluminum alloy plate after pre-aging treatment, and then artificially ages the aluminum alloy plate after pre-aging treatment for 4h to reach the hardness of the commercially available T6 state aluminum alloy plate, so that the formability and strength of the aluminum alloy are considered, the heat treatment time is saved, and the production cost is reduced.

Description

[Technical Field]

[0001] This invention relates to the field of aluminum alloy heat treatment technology, and in particular to a method for heat treating aluminum alloys. [Background Technology]

[0002] Al-Mg-Si aluminum alloys are widely used in the automotive and electronics industries. These alloys exhibit excellent mechanical properties and anodizing performance in the T6 temper (heat-treated state). However, in practical applications, T6 temper sheets typically require higher forming temperatures to achieve better formability, although this results in a decrease in strength. To balance the formability and strength of Al-Mg-Si aluminum alloys, a conventional approach is to use a T4 temper aluminum alloy with higher elongation, followed by heat treatment to increase strength (holding at 175℃ for 12 hours) to achieve the strength level of commercially available T6 temper products. However, this method requires prolonged heating for 12 hours, consuming more energy, incurring higher costs, and resulting in a longer production cycle.

[0003] Therefore, the present invention provides a heat treatment method for aluminum alloys that can reduce the heat treatment time required to improve the strength of T4 state aluminum alloys in conventional methods, while taking into account both formability and strength. Moreover, the heat treatment method of the present invention can make the peak strength of the final aluminum alloy product exceed that of commercially available T6 state aluminum alloys. [Summary of the Invention]

[0004] The technical problem this invention aims to solve is that, in order to balance the formability and strength of aluminum alloys, the conventional approach involves using T4-tempered aluminum alloys with high elongation to form the alloy and then subjecting it to heat treatment to enhance strength, achieving the strength level of commercially available T6-tempered alloys. However, this method requires prolonged heating, consuming more energy, incurring higher costs, and extending the production cycle. This invention provides an aluminum alloy heat treatment method to address these problems.

[0005] The solution to the technical problem of this invention is: a heat treatment method for aluminum alloys, comprising the following steps:

[0006] (1) Solution treatment: T6 aluminum alloy rolled plate is kept at 520℃ for 1 hour and then cooled to room temperature by water.

[0007] (2) Pre-aging treatment: The board after solution treatment in step (1) is kept at 90°C for 1 hour and then air-cooled to room temperature to obtain the board after pre-aging.

[0008] (3) Artificial aging treatment: The board that has been pre-aged in step (2) is kept at 175℃ for 4h to 12h and then air-cooled to room temperature.

[0009] Preferably, the pre-aged board is subjected to natural aging treatment after step (2) and before step (3), that is, the pre-aged board is placed at room temperature, and the board is cut into strips and formed during the natural aging treatment stage.

[0010] Preferably, the natural aging process takes 4 weeks.

[0011] The beneficial effects of this invention are as follows: The heat treatment method for aluminum alloys of this invention first performs solution treatment and pre-aging treatment on T6 state aluminum alloy rolled sheets to obtain aluminum alloy sheets that have completed pre-aging treatment. Then, the aluminum alloy sheets that have completed pre-aging treatment undergo artificial aging treatment for 4 hours to achieve the hardness of commercially available T6 state aluminum alloy sheets. Compared with the prior art, which requires 12 hours of heat treatment of commercially available T4 state aluminum alloys to achieve the hardness of commercially available T6 state aluminum alloy sheets, this method saves a significant amount of time. At the same time, it takes into account the formability and strength of aluminum alloys, saves heat treatment time, and reduces production costs.

Detailed Implementation Methods

[0012] To further illustrate the technical means and effects of the present invention, the following detailed description is provided in conjunction with embodiments of the present invention.

[0013] This invention provides a heat treatment method for aluminum alloys, comprising the following steps:

[0014] S1: Solution treatment: T6 state aluminum alloy rolled plate is kept at 520℃ for 1 hour and then water-cooled to room temperature;

[0015] S2: Pre-aging treatment: The board after solution treatment in step S1 is kept at 90℃ for 1 hour and then air-cooled to room temperature to obtain the board after pre-aging.

[0016] S3: Artificial aging treatment: The board material that has been pre-aged in step S2 is kept at 175℃ for 4 to 12 hours and then air-cooled to room temperature.

[0017] In this process, after step S2 and before step S3, the pre-aged board is subjected to natural aging treatment, which means that the pre-aged board in step S2 is placed at room temperature, and the board is cut into strips and formed during the natural aging treatment stage.

[0018] The natural aging process takes 4 weeks.

[0019] The T6 state aluminum alloy rolled plate is selected from Al-Mg-Si system 6063 aluminum alloy T6 state rolled plate, which is a commercially available product that is readily available.

[0020] Compare with Example 1

[0021] T4 state aluminum alloy rolled sheet.

[0022] Compare with Example 2

[0023] T4 state aluminum alloy rolled sheet was kept at 175℃ for 12 hours.

[0024] Compare with Example 3

[0025] T6 aluminum alloy rolled sheet.

[0026] Compare with Example 4

[0027] A heat treatment method for aluminum alloys includes the following steps:

[0028] S100: Solution treatment: T6 state aluminum alloy rolled plate is kept at 520℃ for 1 hour and then water-cooled to room temperature;

[0029] S200: Pre-aging treatment: The board after solution treatment in step S100 is kept at 90℃ for 1 hour and then air-cooled to room temperature to obtain the board after pre-aging.

[0030] S300: Artificial aging treatment: The board that has completed pre-aging in step S200 is kept at 175℃ for 3 hours and then air-cooled to room temperature.

[0031] Example 1

[0032] A heat treatment method for aluminum alloys includes the following steps:

[0033] S101: Solution treatment: T6 state aluminum alloy rolled plate is kept at 520℃ for 1 hour and then water-cooled to room temperature;

[0034] S201: Pre-aging treatment: The board material after solution treatment in step S101 is kept at 90℃ for 1 hour and then air-cooled to room temperature to obtain the board material after pre-aging.

[0035] S301: Artificial aging treatment: The board material that has completed pre-aging in step S201 is kept at 175℃ for 4 hours and then air-cooled to room temperature.

[0036] Example 2

[0037] A heat treatment method for aluminum alloys includes the following steps:

[0038] S102: Solution treatment: T6 state aluminum alloy rolled plate is kept at 520℃ for 1 hour and then water-cooled to room temperature;

[0039] S202: Pre-aging treatment: The board after solution treatment in step S102 is kept at 90°C for 1 hour and then air-cooled to room temperature to obtain the board after pre-aging.

[0040] S302: Artificial aging treatment: The board material that has completed pre-aging in step S202 is kept at 175℃ for 5 hours and then air-cooled to room temperature.

[0041] Example 3

[0042] A heat treatment method for aluminum alloys includes the following steps:

[0043] S103: Solution treatment: T6 state aluminum alloy rolled plate is kept at 520℃ for 1 hour and then water-cooled to room temperature;

[0044] S203: Pre-aging treatment: The board after solution treatment in step S103 is kept at 90℃ for 1 hour and then air-cooled to room temperature to obtain the board after pre-aging.

[0045] S303: Artificial aging treatment: The board that has completed the pre-aging in step S203 is kept at 175℃ for 6 hours and then air-cooled to room temperature.

[0046] Example 4

[0047] A heat treatment method for aluminum alloys includes the following steps:

[0048] S104: Solution treatment: T6 state aluminum alloy rolled plate is kept at 520℃ for 1 hour and then water-cooled to room temperature;

[0049] S204: Pre-aging treatment: The board after solution treatment in step S104 is kept at 90°C for 1 hour and then air-cooled to room temperature to obtain the board after pre-aging.

[0050] S304: Artificial aging treatment: The board material that has completed pre-aging in step S204 is kept at 175℃ for 7 hours and then air-cooled to room temperature.

[0051] Example 5

[0052] A heat treatment method for aluminum alloys includes the following steps:

[0053] S105: Solution treatment: T6 state aluminum alloy rolled plate is kept at 520℃ for 1 hour and then water-cooled to room temperature;

[0054] S205: Pre-aging treatment: The board after solution treatment in step S105 is kept at 90℃ for 1 hour and then air-cooled to room temperature to obtain the board after pre-aging.

[0055] S305: Artificial aging treatment: The board that has completed the pre-aging in step S205 is kept at 175℃ for 8 hours and then air-cooled to room temperature.

[0056] Example 6

[0057] A heat treatment method for aluminum alloys includes the following steps:

[0058] S106: Solution treatment: T6 state aluminum alloy rolled plate is kept at 520℃ for 1 hour and then water-cooled to room temperature;

[0059] S206: Pre-aging treatment: The board after solution treatment in step S106 is kept at 90°C for 1 hour and then air-cooled to room temperature to obtain the board after pre-aging.

[0060] S306: Artificial aging treatment: The board material that has completed pre-aging in step S206 is kept at 175℃ for 12 hours and then air-cooled to room temperature.

[0061] Example 7

[0062] A heat treatment method for aluminum alloys includes the following steps:

[0063] S107: Solution treatment: T6 state aluminum alloy rolled plate is kept at 520℃ for 1 hour and then water-cooled to room temperature;

[0064] S207: Pre-aging treatment: The board after solution treatment in step S107 is kept at 90℃ for 1 hour and then air-cooled to room temperature to obtain the board after pre-aging.

[0065] S307: Natural aging treatment: Place the board material that has completed the pre-aging in step S207 at room temperature for 2 days.

[0066] Example 8

[0067] A heat treatment method for aluminum alloys includes the following steps:

[0068] S108: Solution treatment: T6 state aluminum alloy rolled plate is kept at 520℃ for 1 hour and then water-cooled to room temperature;

[0069] S208: Pre-aging treatment: The board after solution treatment in step S108 is kept at 90℃ for 1 hour and then air-cooled to room temperature to obtain the board after pre-aging.

[0070] S308: Natural aging treatment: Place the pre-aged board material from step S208 at room temperature for 4 weeks.

[0071] Example 9

[0072] A heat treatment method for aluminum alloys includes the following steps:

[0073] S109: Solution treatment: Hold the T6 state aluminum alloy rolled plate at 520℃ for 1 hour, then water cool to room temperature;

[0074] S209: Pre-aging treatment: The board after solution treatment in step S109 is kept at 90°C for 1 hour and then air-cooled to room temperature to obtain the board after pre-aging.

[0075] S309: Natural aging treatment: Place the pre-aged board material from step S209 at room temperature for 4 weeks.

[0076] S409: Artificial aging treatment: The board material that has undergone natural aging treatment in step S309 is kept at 175℃ for 4 hours and then air-cooled to room temperature.

[0077] The aluminum alloy rolled sheets used in Comparative Examples 1-4 and Examples 1-9 above were all Al-Mg-Si 6063 aluminum alloys produced by the same manufacturer. Comparative Examples 1-2 were rolled sheets from the same batch in the T4 state, while Comparative Examples 3-4 and Examples 1-9 were rolled sheets from the same batch in the T6 state. Hardness tests were performed on the aluminum alloy sheets obtained in Comparative Examples 1-4 and Examples 1-9, and the test results are shown in the table below:

[0078] Table 1 Test Results

[0079]

[0080]

[0081] The experimental data above show that the present invention has the following beneficial effects:

[0082] 1. By comparing Comparative Example 2, Comparative Example 3 and Example 1, it can be seen that the heat treatment method of aluminum alloy of the present invention first performs solution treatment and pre-aging treatment on T6 state aluminum alloy rolled plate to obtain aluminum alloy plate after pre-aging treatment. Then, the aluminum alloy plate after pre-aging treatment is subjected to artificial aging treatment for 4 hours to achieve the hardness of commercially available T6 state aluminum alloy plate. Compared with the 12 hours of heat treatment (holding at 175℃) of commercially available T4 state aluminum alloy to achieve the hardness of commercially available T6 state aluminum alloy plate, it saves a lot of time.

[0083] 2. By comparing Example 6, Comparative Example 2 and Comparative Example 3, it can be seen that the hardness (peak hardness) of the aluminum alloy sheet after pre-aging treatment is higher than that of the T4 state aluminum alloy after heat treatment for 12 hours (the hardness of the T6 state aluminum alloy sheet).

[0084] 3. By comparing Comparative Example 1 with Examples 7 and 8, it can be seen that the hardness value of the pre-aged aluminum alloy sheet after 4 weeks and 2 days of room temperature storage is higher than that of T4 state aluminum alloy. Moreover, the hardness value of the pre-aged aluminum alloy sheet after 4 weeks and 2 days of room temperature storage is relatively small, and the hardness value does not change significantly, so it can be stably used for forming and processing. By comparing Example 9 with Comparative Example 3, it can be seen that the aluminum alloy sheet that has undergone pre-aging treatment after natural aging (4 weeks of room temperature storage) can still reach the hardness level of commercially available T6 state aluminum alloy sheet after 4 hours of artificial aging. The 4-week natural aging time is sufficient to complete the cutting, slitting, forming and processing of the aluminum alloy sheet, leaving enough time for production.

[0085] It should be noted that the present invention is not limited to the above embodiments. Any simple modifications, equivalent changes and alterations made by those skilled in the art to the above embodiments based on the technical solutions of the present invention shall fall within the protection scope of the present invention.

Claims

1. A heat treatment method for aluminum alloys, characterized in that, Includes the following steps: (1) Solution treatment: T6 aluminum alloy rolled plate is kept at 520℃ for 1 hour and then cooled to room temperature by water. (2) Pre-aging treatment: The board after solution treatment in step (1) is kept at 90°C for 1 hour and then air-cooled to room temperature to obtain the board after pre-aging. (3) Artificial aging treatment: The board that has been pre-aged in step (2) is kept at 175℃ for 4h to 12h and then air-cooled to room temperature.

2. The heat treatment method for aluminum alloys as described in claim 1, characterized in that: After step (2) and before step (3), the pre-aged board is subjected to natural aging treatment, that is, the pre-aged board in step (2) is placed at room temperature, and the board is cut into strips and formed during the natural aging treatment stage.

3. The aluminum alloy heat treatment method as described in claim 2, characterized in that: The natural aging process takes 4 weeks.

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