Ultra-fast zoned contact heating aluminum alloy hot stamping forming apparatus and method

Abstract

A method and apparatus for ultra-fast zoned contact heating of aluminum alloy hot stamping forming is disclosed. The method involves determining the temperature distribution of the zoned contact heating mold based on the aluminum alloy sheet to be processed, placing the sheet on the mold for ultra-fast zoned contact heating to form temperature zones, and then rapidly transferring the heated aluminum alloy sheet to the hot stamping mold using a progressive die sheet transfer device. The hot stamping mold is then closed to stamp the aluminum alloy sheet into the target shape and held under pressure for cooling to obtain the corresponding part. Finally, the hot-stamped part undergoes a baking paint treatment to achieve peak strength in overall performance. This invention uses age-hardened (T-state) aluminum alloy sheet through rapid zoned contact heating and hot stamping forming processes to obtain parts, utilizing the continuous and efficient advantages of progressive stamping to integrate heating, transfer, and forming into a single mold.

Description

Technical Field

[0001] This invention relates to a technology in the field of metal sheet forming and processing, specifically an ultra-fast zoned contact heating aluminum alloy hot stamping forming device and method. Background Technology

[0002] With the rapid development of new energy vehicles, high-strength aluminum alloy components have been widely used. However, room temperature forming of high-strength aluminum alloys has defects such as easy cracking and large springback, which cannot meet the manufacturing requirements of vehicle body structural parts. The existing aluminum alloy hot stamping process HFQ uses a set of molds to achieve forming and quenching. With subsequent artificial aging, the shape and properties of the parts can be controlled in a coordinated manner. However, this technology has a slow production cycle and long cycle: the heating and solution treatment time is long (20-40 minutes) and the aging time is long (12-24 hours), which cannot meet the needs of mass production, high efficiency and low cost in automobile manufacturing. The performance of the parts after hot stamping (W state) is unstable: the natural aging of the W state affects the final mechanical properties after artificial aging, and there are high requirements for the artificial aging system and the storage period.

[0003] Existing technologies further improve the hot stamping forming of lightweight aluminum alloy body components. For aluminum alloy sheets in the T6 state, the heating rate is controlled at 1-10℃ / s. High-temperature heat preservation is used to dissolve the precipitated phase and improve plasticity, so that the formed parts have the strength of the T4 state. Finally, the T8 state strength is obtained through baking paint treatment. However, the defects and shortcomings of this technology are: (1) The heating rate of aluminum alloy sheet is slow, which can easily lead to abnormal dissolution or excessive growth of the aluminum alloy precipitated strengthening phase, resulting in a loss of alloy strength; (2) The heating and transfer of aluminum alloy sheet require special equipment, resulting in high production costs; (3) The heating temperature of aluminum alloy sheet is singular, and it is impossible to customize the heating temperature according to the sheet forming conditions. Summary of the Invention

[0004] This invention addresses the problem that existing hot stamping processes require solution treatment and long-term artificial aging when forming soft blanks. It proposes an ultra-fast partitioned contact heating method and apparatus for hot stamping of aluminum alloys. The method uses age-strengthened (T-state) aluminum alloy sheets and obtains parts through rapid partitioned contact heating and hot stamping processes. It integrates heating, transfer and forming into a single mold by utilizing the continuous and efficient advantages of progressive stamping.

[0005] This invention is achieved through the following technical solution:

[0006] This invention relates to an ultra-fast zoned contact heating aluminum alloy hot stamping forming method. The method involves determining the temperature distribution of the zoned contact heating mold based on the aluminum alloy sheet to be processed, placing the sheet on the contact heating mold for ultra-fast zoned contact heating to form temperature zones, rapidly transferring the heated aluminum alloy sheet to the hot stamping mold using a progressive die sheet transfer device, and then closing the hot stamping forming mold to stamp the aluminum alloy sheet into the target shape and holding it under pressure to obtain the corresponding part. Finally, the hot stamped part undergoes a baking paint treatment to achieve peak strength in overall performance.

[0007] The temperature zoning refers to the control of sheet metal forming performance through ultra-fast zoned contact heating, including: the high-temperature heating zone utilizes the re-dissolution and plasticization of precipitated phases to improve the forming limit of easily cracked parts, and the low-temperature heating zone restricts the re-dissolution of precipitated phases to ensure the mechanical properties of most small deformation areas, thereby realizing the forming of complex shaped parts.

[0008] The aluminum alloy sheet to be processed includes: 7075-T6 aluminum alloy sheet or 7075 under-aged aluminum alloy sheet.

[0009] The aforementioned under-aged sheet material refers to the sheet material obtained by dissolving AA7075-T6 aluminum alloy material at 475℃ for 30 minutes, quenching it in water, and then aging it at 120℃ for 5 hours.

[0010] The ultra-fast zoned contact heating refers to: optimizing and determining the temperature distribution of the zoned contact heating mold based on the conditions of the aluminum alloy sheet, optimizing and setting the heating temperature of each contact heating module and controlling the temperature independently, placing the aluminum alloy sheet on the contact heating mold for rapid heating, and realizing ultra-fast zoned heating.

[0011] The high-temperature heating zone refers to a zone where the temperature is heated to 250-400℃, the heating rate is greater than or equal to 80℃ / s, and the heating time is 5-10s.

[0012] The aforementioned low-temperature heating zone refers to a zone where the temperature is heated to 150-250℃ at a rate greater than or equal to 80℃ / s, and the heating time is 5-10s.

[0013] The aforementioned precipitate re-dissolution plasticization refers to the phenomenon where, in the high-temperature heating zone between 250-400℃, the aluminum alloy sheet temperature is close to the solution temperature, resulting in a significant increase in the alloy's plastic deformation capacity due to the occurrence of a large amount of precipitate re-dissolution.

[0014] The aforementioned limitation on precipitate re-dissolution refers to the following: the temperature range of the low-temperature heating zone is 150-250℃, the temperature of the aluminum alloy sheet is much lower than the solid solution temperature, and the amount of precipitate re-dissolution is small.

[0015] The aforementioned rapid transfer refers to a transfer time of 1-2 seconds for sheet metal within the progressive die;

[0016] The aforementioned pressure holding and cooling refers to a cooling rate of 30°C / s or greater for the sheet metal within the hot stamping die, with the pressure holding time being the same as the contact heating time.

[0017] The baking paint process involves a temperature of 180-185℃ and a baking time of approximately 20 minutes.

[0018] Technical effect

[0019] This invention addresses the shortcomings of existing technologies, such as slow production cycle, long production time, and low efficiency. These shortcomings include long heating and solution time (20-40 minutes) and long aging time (12-24 hours), which cannot meet the needs of mass production, high efficiency, and low cost in automobile manufacturing.

[0020] Compared with existing technologies, this invention utilizes the similar cycle time of rapid contact heating and hot stamping forming processes to integrate heating, transfer, and forming into a single progressive die. This results in high process integration, stable and controllable cycle time, and eliminates the need for manual aging. Combined with the painting process in vehicle body manufacturing, the peak strength of aluminum alloy can be achieved or approached through painting alone, significantly improving production efficiency. It fully leverages the advantages of continuous industrial production and is suitable for the mass production of high-strength aluminum alloy thin-walled components for automobiles. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the progressive die structure of the present invention;

[0022] Figure 2 This is a schematic diagram of the contact heating mold structure in Embodiment 1 of the present invention;

[0023] Figure 3 This is a schematic diagram of the contact heating mold structure in Embodiment 2 of the present invention;

[0024] Figure 4 This is a schematic diagram of the contact heating mold structure in Embodiment 3 of the present invention;

[0025] Figure 5 This is a schematic diagram of the component structure of the present invention;

[0026] Figure 6 This is a schematic diagram of the baking paint process of the present invention;

[0027] Figure 7 Simulation curves of contact heating / cooling-down of aluminum alloy 7075 sheet with contact heating die material Cu and hot forming die material H13;

[0028] Figure 8 This is a schematic diagram of the preparation path of the under-aged aluminum alloy sheet of the present invention;

[0029] Figure 9 This is a schematic diagram of the sheet material temperature path of the present invention;

[0030] Figure 10 This is a schematic diagram of the evolution of the sheet metal structure according to the present invention;

[0031] The components include: 1. Sheet metal, 2. Progressive die, 21. Progressive die sheet metal transfer device, 3. Contact heating die, 31. Contact heating module, 311. Low temperature contact heating module, 312. High temperature contact heating module, 32. Heating channel, 4. Hot stamping forming die, 41. Punch, 42. Die, 43. Cooling channel, 5. Parts, 6. Painting environment. Detailed Implementation

[0032] Example 1

[0033] like Figure 1 As shown in this embodiment, an integrated device for ultra-fast zoned contact heating and hot stamping of aluminum alloy includes: a progressive die 2 and a contact heating die 3 with heating channels 32 and a hot stamping die 4 with cooling channels 43 arranged side by side inside the progressive die 2. A progressive die sheet transfer device 21 is provided between the contact heating die 3 and the hot stamping die 4. The progressive die sheet transfer device 21 rapidly transfers the contact-heated aluminum alloy sheet 1 from the contact heating die 3 to the hot stamping die 4 to achieve hot stamping. The heating channels 32, used to insert heating rods or introduce high-temperature circulating media, are installed through the contact heating die 3. The cooling channels 43, used to cool the sheet, are installed through the hot stamping die 4. Utilizing the high efficiency, fast cycle time, and high integration of the progressive die, the progressive die 2 enables rapid transfer of the aluminum alloy sheet, the contact heating die 3 enables zoned heating and performance customization of the sheet, and the hot stamping die 4 enables hot stamping. The ultra-fast zoned contact heating, transfer, and hot stamping processes are integrated into a single progressive die.

[0034] like Figure 6 As shown, the baking paint device 6 involved in this embodiment is used to perform baking paint treatment on the part 5.

[0035] like Figure 1 , Figure 2 , Figure 5 , Figure 6 , Figure 7 , Figure 9 and Figure 10 As shown, this embodiment involves an ultrafast zoned contact heating and hot stamping forming method for 7075-T6 aluminum alloy plates, specifically including:

[0036] Step 1) Rapid Sectional Contact Heating of Sheet Material: The 7075-T6 aluminum alloy sheet 1 is brought into contact with the high-temperature contact heating mold 3 inside the progressive die 2 for rapid sectional heating. Heating rods are inserted into the heating channel 32 for heating. The average heating rate is about 80℃ / s, and the holding time is 8s. The contact heating module 31 is divided into two parts: a low-temperature contact heating module 311 and a high-temperature contact heating module 312. Both are made of Cu. In order to ensure the formability of complex geometric feature areas on part 5, the heating temperature of the high-temperature contact heating module 312 is set to 250℃. In order to ensure the final mechanical properties of other areas on part 5, the heating temperature of the low-temperature contact heating module 311 is set to 150℃.

[0037] Step 2) Rapid transfer of sheet metal: The progressive die sheet metal transfer device 21 rapidly transfers the 7075 aluminum alloy sheet metal 1 after partition heating to the hot stamping die 4, with a transfer time of 1.5s;

[0038] Step 3) Hot stamping: The hot stamping die 4 is closed for hot stamping and pressure holding, cooling and quenching to obtain 7075 aluminum alloy part 5. The punch 41 and die 42 are made of H13. Circulating cooling water is introduced into the cooling channel 43 to cool the hot stamping die 4. The holding pressure is adjusted so that the average cooling rate is greater than 30℃ / s. The holding time is the same as the contact heating time.

[0039] Step 4) Baking paint treatment: Place the 7075 aluminum alloy part 5 into the baking paint environment 6 for baking paint treatment. The baking paint temperature is 185℃ and the baking paint time is 20min to obtain the final aluminum alloy part. The mechanical properties of the alloy in the high temperature heating zone can reach 90% of the peak strength of the aluminum alloy, and the mechanical properties in the low temperature heating zone can reach more than 95% of the peak strength of the aluminum alloy.

[0040] In this embodiment, the total time for heating, transferring, and forming the aluminum alloy sheet is 9.5 seconds, which significantly improves efficiency.

[0041] like Figure 2 As shown, the contact heating mold 3 includes: a contact heating module 31, a low-temperature contact heating module 311, a high-temperature contact heating module 312, and a heating channel 32. The purpose of setting the high-temperature contact heating module 312 and the low-temperature contact heating module 311 is to control the heating temperature of the sheet metal in zones to customize the sheet metal forming performance. The number, shape, arrangement, and heating temperature of the high-temperature contact heating module 312 and the low-temperature contact heating module 311 can be optimized according to the solution temperature of the aluminum alloy sheet metal, the dissolution temperature of the strengthening phase, the high-temperature formability, and the complexity of the part shape. This zoned contact heating mold is made of high thermal conductivity and high wear resistance materials, such as copper and copper alloys, and high thermal conductivity hot work die steel. This zoned contact heating mold uses high-power heating rods and high-temperature circulating media for heating and temperature control, with a temperature control error of no more than ±2℃.

[0042] like Figure 7 The figure shows the simulated heating / cooling curves of aluminum alloy 7075 sheet with contact heating die material Cu and hot forming die material H13. It can be seen that the sheet can maintain a heating rate of 80℃ / s during contact heating and a cooling rate of 30℃ / s during pressure holding cooling. Figure 9 and Figure 10 The figure shows the formability and microstructure evolution of 7075-T6 aluminum alloy sheet under different heating temperatures. It can be seen that the formability and microstructure evolution of the sheet are quite different when heated at high temperature and low temperature, and the mechanical properties after forming are also different.

[0043] Example 2

[0044] like Figure 1 , Figure 3 and Figure 6 As shown, this embodiment involves an ultrafast contact heating and hot stamping method for 7075-T6 aluminum alloy plates, specifically including:

[0045] Step 1) Rapid zoned contact heating of sheet metal: The 7075-T6 aluminum alloy sheet 1 is brought into contact with the high-temperature contact heating mold 3 in the progressive die 2 for rapid heating under pressure. Heating rods are inserted into the heating channel 32 for heating. In order to ensure the formability of complex geometric feature areas on part 5, the heating temperature of the high-temperature contact heating module 312 is set to 250℃; the average heating rate is about 80℃ / s, and the pressure holding time is 8s.

[0046] Step 2) Rapid transfer of sheet metal: The progressive die sheet metal transfer device 21 rapidly transfers the 7075 aluminum alloy sheet metal 1 after partition heating to the hot stamping die 4, with a transfer time of 1.5s;

[0047] Step 3) Hot stamping: The hot stamping die 4 is closed for hot stamping and pressure holding, cooling and quenching to obtain 7075 aluminum alloy part 5. The punch 41 and die 42 are made of H13. Circulating cooling water is introduced into the cooling channel 43 to cool the hot stamping die 4. The holding pressure is adjusted so that the average cooling rate is greater than 30℃ / s. The holding time is the same as the contact heating time.

[0048] Step 4) Baking paint treatment: Place the 7075 aluminum alloy part 5 into the baking paint environment 6 for baking paint treatment. The baking paint temperature is 185℃ and the baking paint time is 20 minutes to obtain the final aluminum alloy part. Its overall mechanical properties can reach 90% of the peak strength of aluminum alloy.

[0049] In this embodiment, the total time for heating, transferring, and forming the aluminum alloy sheet is 9.5 seconds, which significantly improves efficiency.

[0050] In this embodiment, the three-dimensional structure of the contact heating mold 3 is as follows: Figure 3 As shown, the temperature of each high-temperature contact heating module 312 is set to 250℃; the temperature is uniform and consistent, which is used to achieve uniform heating of the sheet metal, and can maximize its formability, forming aluminum alloy parts with more complex structural shapes. Using the contact heating mold 3 with this structure, the resulting aluminum alloy parts 5 have a more uniform and consistent spatial distribution of properties.

[0051] Example 3

[0052] like Figure 1 , Figure 4 and Figure 6 As shown, this embodiment involves an ultrafast contact heating and hot stamping method for 7075-T6 aluminum alloy plates, specifically including:

[0053] Step 1) Rapid zoned contact heating of sheet metal: The 7075-T6 aluminum alloy sheet metal 1 is brought into contact with the high-temperature contact heating mold 3 in the progressive die 2 for rapid heating under pressure. Heating rods are inserted into the heating channel 32 for heating. In order to achieve zoned customization of the final aluminum alloy parts performance, the heating temperature of the low-temperature contact heating module 311 is set to 150℃, the heating temperature of the high-temperature contact heating module 312 is set to 400℃, the average heating rate is about 80℃ / s, and the pressure holding time is 8s.

[0054] Compared with Example 2, this example heats the entire aluminum alloy sheet uniformly to maximize its formability. At the same time, it heats the aluminum alloy sheet in sections according to the deformation characteristics of the parts, so as to achieve customized mechanical properties of the parts in sections.

[0055] Step 2) Rapid transfer of sheet metal: The progressive die sheet metal transfer device 21 rapidly transfers the 7075 aluminum alloy sheet metal 1 after partition heating to the hot stamping die 4, with a transfer time of 1.5s;

[0056] Step 3) Hot stamping: The hot stamping die 4 is closed for hot stamping and pressure holding, cooling and quenching to obtain 7075 aluminum alloy part 5. The punch 41 and die 42 are made of H13. Circulating cooling water is introduced into the cooling channel 43 to cool the hot stamping die 4. The holding pressure is adjusted so that the average cooling rate is greater than 30℃ / s. The holding time is the same as the contact heating time.

[0057] Step 4) Baking paint treatment: Place the 7075 aluminum alloy part 5 into the baking paint environment 6 for baking paint treatment. The baking paint temperature is 185℃ and the baking paint time is 20min to obtain the final aluminum alloy part. The mechanical properties of the alloy in the high temperature heating zone are close to 65% of the peak strength of the aluminum alloy, and the mechanical properties in the low temperature heating zone can reach more than 95% of the peak strength of the aluminum alloy.

[0058] In this embodiment, the total time for heating, transferring, and forming the aluminum alloy sheet is 9.5 seconds, which significantly improves efficiency.

[0059] In this embodiment, the three-dimensional structure of the contact heating mold 3 is as follows: Figure 4 As shown, while ensuring formability, the low-temperature heating module 311 and the high-temperature heating module 312 are set to different temperatures. The high-temperature heating module 312 is used to soften the aluminum alloy by causing a large amount of precipitated phases to dissolve back. The heating temperature of the low-temperature heating module 311 is controlled below the melting start temperature to avoid melting back. Through the subsequent baking paint process, the strength of the low-temperature heated zone reaches the T6 state. By controlling the heating temperature of the high-temperature heating module 312, the strength and toughness of the soft zone are regulated, thereby achieving zoned customization of the performance of the aluminum alloy parts. The number, shape, arrangement, and heating temperature of the heating modules can be flexibly set according to actual needs.

[0060] Example 4

[0061] like Figure 1 , Figure 4 and Figure 6 As shown, this embodiment involves an ultrafast contact heating and hot stamping method for 7075 under-aging aluminum alloy plates, specifically including:

[0062] Step 1) Rapid zoned contact heating of sheet metal: The 7075 under-aging aluminum alloy sheet 1 is brought into contact with the high-temperature contact heating mold 3 in the progressive mold 2 for rapid heating under pressure. Heating rods are inserted into the heating channel 32 for heating. In order to form the complex shape area of ​​the upper part of the part and to achieve the zoned customization of the final aluminum alloy part performance, the heating temperature of the low-temperature contact heating module 311 is set to 180℃, the heating temperature of the high-temperature contact heating module 312 is set to 200℃, the average heating rate is about 80℃ / s, and the pressure holding time is 8s.

[0063] Step 2) Rapid transfer of sheet metal: The progressive die sheet metal transfer device 21 rapidly transfers the 7075 aluminum alloy sheet metal 1 after partition heating to the hot stamping die 4, with a transfer time of 1.5s;

[0064] Step 3) Hot stamping: The hot stamping die 4 is closed for hot stamping and pressure holding, cooling and quenching to obtain 7075 aluminum alloy part 5. The punch 41 and die 42 are made of H13. Circulating cooling water is introduced into the cooling channel 43 to cool the hot stamping die 4. The holding pressure is adjusted so that the average cooling rate is greater than 30℃ / s. The holding time is the same as the contact heating time.

[0065] Step 4) Baking paint treatment: Place the 7075 aluminum alloy part 5 into the baking paint environment 6 for baking paint treatment. The baking paint temperature is 185℃ and the baking paint time is 20 minutes to obtain the final aluminum alloy part. Its overall mechanical properties can reach more than 98% of the peak strength of aluminum alloy.

[0066] In this embodiment, the total time for heating, transferring, and forming the aluminum alloy sheet is 9.5 seconds, which significantly improves efficiency.

[0067] In this embodiment, the three-dimensional structure of the contact heating mold 3 is as follows: Figure 4 As shown, while ensuring formability, the low-temperature heating module 311 and the high-temperature heating module 312 are set to different temperatures. The high-temperature heating module 312 is used to soften the aluminum alloy by causing a large amount of precipitated phases to dissolve back. The heating temperature of the low-temperature heating module 311 is controlled below the melting start temperature to control the amount of precipitated phases to dissolve back. Through the subsequent baking paint process, the strength of the low-temperature heated zone reaches the T6 state. By controlling the heating temperature of the high-temperature heating module 312, the strength and toughness of the soft zone are regulated, thereby achieving zoned customization of the performance of aluminum alloy parts. The number, shape, arrangement, and heating temperature of the heating modules can be flexibly set according to actual needs.

[0068] This invention utilizes age-hardened (T-state) aluminum alloy sheets through rapid, zoned contact heating and hot stamping processes to obtain custom-designed parts with varying performance zones. It also leverages the continuous and efficient advantages of progressive stamping to integrate heating, transfer, and forming into a single mold. Compared to conventional techniques, the sheet metal undergoes zoned contact heating on a contact heating mold. The high-temperature heating zone ranges from 250-400℃, the low-temperature heating zone ranges from 150-250℃, the heating rate is greater than or equal to 80℃ / s, the contact heating time is 5-10s, and the transfer speed of the progressive mold sheet metal transfer device is extremely fast (1-2s).

[0069] In summary, the highly integrated progressive die 2 of this invention enables rapid transfer of aluminum alloy sheets, significantly improving production efficiency. By controlling the number, shape, arrangement, and heating temperature of the contact heating modules through the contact heating die 3, flexible zoned control of the sheet heating temperature is achieved, thereby enabling zoned control of the sheet forming performance. This allows for the forming of complex-shaped parts and also allows for customized zoned performance of parts. This invention shortens the single-piece production cycle to less than 10 seconds, eliminates the manual aging process, and achieves production efficiency exceeding that of boron steel hot stamping (3-4 strokes / minute). Furthermore, the method of this invention also allows for customized zoned performance of parts.

[0070] The above-described specific implementations can be partially adjusted by those skilled in the art in different ways without departing from the principles and purpose of the present invention. The scope of protection of the present invention is defined by the claims and is not limited to the above-described specific implementations. All implementation schemes within the scope of the claims are bound by the present invention.

Claims

1. A forming method based on an integrated device for ultrafast zoned contact heating of aluminum alloy hot stamping, characterized in that, The aluminum alloy sheet used is an age-hardened aluminum alloy sheet. The integrated device includes a progressive die and two adjacent hot stamping forming dies with heating channels and cooling channels. A progressive die sheet transfer device is provided between the contact heating die and the hot stamping forming die. This device rapidly transfers the contact-heated aluminum alloy sheet from the contact heating die to the hot stamping forming die to achieve hot stamping forming. Heating channels for inserting heating rods or introducing high-temperature circulating media are installed throughout the contact heating die, and cooling channels for cooling the sheet are installed throughout the hot stamping forming die. Utilizing the high efficiency, fast cycle time, and high integration of the progressive die, the progressive die enables rapid transfer of the aluminum alloy sheet, the contact heating die enables zoned heating and performance customization of the sheet, and the hot stamping die enables hot stamping forming. This integrates ultra-fast zoned contact heating, transfer, and hot stamping forming processes into a single progressive die. The ultra-fast zoned contact heating aluminum alloy hot stamping forming refers to: determining the temperature distribution of the zoned contact heating mold according to the aluminum alloy sheet to be processed; placing the sheet on the contact heating mold for ultra-fast zoned contact heating to form temperature zones; rapidly transferring the heated aluminum alloy sheet to the hot stamping mold by a progressive die sheet transfer device; and stamping the aluminum alloy sheet into the target shape by closing the hot stamping forming mold and holding it under pressure to obtain the corresponding part; finally, baking paint is applied to the hot stamped part to achieve the peak strength of the overall performance. The temperature zoning refers to: controlling the forming performance of sheet metal through ultra-fast zoned contact heating, including: the high-temperature heating zone utilizes the re-dissolution and plasticization of precipitated phases to improve the forming limit of easily cracked parts, and the low-temperature heating zone restricts the re-dissolution of precipitated phases to ensure the mechanical properties of most small deformation areas, thereby realizing the forming of complex shaped parts; The ultra-fast zoned contact heating refers to: optimizing and determining the temperature distribution of the zoned contact heating mold based on the conditions of the aluminum alloy sheet, optimizing and setting the heating temperature of each contact heating module and controlling the temperature independently, placing the aluminum alloy sheet on the contact heating mold for rapid heating, achieving ultra-fast zoned heating with a heating rate greater than or equal to 80℃ / s; The aforementioned rapid transfer refers to a transfer time of 1-2 seconds for sheet metal within the progressive die.

2. The ultrafast zoned contact heating aluminum alloy hot stamping forming method according to claim 1, characterized in that, The aluminum alloy sheet to be processed includes: 7075-T6 aluminum alloy sheet or 7075 under-aged aluminum alloy sheet; The aforementioned under-aged sheet material refers to the sheet material obtained by dissolving AA7075-T6 aluminum alloy material at 475℃ for 30 minutes, quenching it in water, and then aging it at 120℃ for 5 hours.

3. The ultrafast zoned contact heating aluminum alloy hot stamping forming method according to claim 1, characterized in that, The high-temperature heating zone refers to a zone where the temperature is heated to 250-400℃, the heating rate is greater than or equal to 80℃ / s, and the heating time is 5-10s.

4. The ultrafast zoned contact heating aluminum alloy hot stamping forming method according to claim 1, characterized in that, The aforementioned low-temperature heating zone refers to a zone where the temperature is heated to 150-250℃ at a rate greater than or equal to 80℃ / s, and the heating time is 5-10s.

5. The ultrafast zoned contact heating aluminum alloy hot stamping forming method according to claim 1, characterized in that, The aforementioned precipitate re-dissolution plasticization refers to the phenomenon where, in the high-temperature heating zone between 250-400℃, the aluminum alloy sheet temperature is close to the solution temperature, resulting in a significant increase in the alloy's plastic deformation capacity due to the occurrence of a large amount of precipitate re-dissolution.

6. The ultrafast zoned contact heating aluminum alloy hot stamping forming method according to claim 1, characterized in that, The aforementioned limitation on precipitate re-dissolution refers to the following: the temperature range of the low-temperature heating zone is 150-250℃, the temperature of the aluminum alloy sheet is much lower than the solid solution temperature, and the amount of precipitate re-dissolution is small.

7. The ultrafast zoned contact heating aluminum alloy hot stamping forming method according to claim 1, characterized in that, The aforementioned rapid transfer refers to a transfer time of 1-2 seconds for sheet metal within the progressive die.

8. The ultrafast zoned contact heating aluminum alloy hot stamping forming method according to claim 1, characterized in that, The aforementioned pressure holding and cooling refers to a cooling rate of 30°C / s or greater for the sheet metal within the hot stamping die, with the pressure holding time being the same as the contact heating time.

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