TWI797844B - A forming process of aluminum alloy sheet - Google Patents

Abstract

A Forming Process of Aluminum Alloy Sheet , concluding a preparing step , an aging forming step , and an out-mold forming step. The preparing step is preparing an aluminum alloy material , a mold ,and a handling apparatus. The aging forming step concludes a heating substep of heating the aluminum alloy material to a first temperature below the solvus temperature and above the solvus temperature of G-P zone, a moving substep transporting the aluminum alloy material into the mold while maintaining a second temperature, and a cooling substep let the aluminum alloy material foming while cooling in the mold. The out-mold forming step is heating to a third temperature below the solvus temperature and above the solvus temperature of G-P zone outside the mold , and aging again to product the aluminum alloy sheet.

Description

Forming and manufacturing method of aluminum alloy workpiece

The invention relates to a manufacturing process of an alloy workpiece, in particular to a forming and manufacturing method of an aluminum alloy workpiece.

Since the aluminum alloy has the characteristic of improving the formability after heating, when forming a specific type of aluminum alloy workpiece, there must be a process of heating to a specific forming temperature, so that the mold can be used to meet the required shape. take shape. Among them, according to the difference in heating temperature, it can be divided into warm forming and thermoforming. In the warm forming method, the aluminum alloy sheet is heated to a temperature above 100°C and below the recrystallization temperature, and then sent to the mold for press forming and cooling at the same time; while in the thermoforming method, it is heated to After reaching the solid solution temperature of the aluminum alloy sheet, it is sent to the mold for press forming and quenched at the same time. In the follow-up, after the thermoforming method is demolded, a period of artificial aging (Aging) treatment is required to achieve the target strength.

However, the post-aging treatment required in the thermoforming method must consume a relatively long working time, and thus the production cost and energy consumption are also increased. Moreover, the molds used must continue to work at high temperatures, and must be matched with the temperature drop of cooling or quenching, so the service life is relatively shortened, which will also increase the production cost.

Therefore, the object of the present invention is to provide a method for forming and manufacturing aluminum alloy workpieces that can effectively reduce production costs and shorten working hours.

Therefore, the forming and manufacturing method of an aluminum alloy workpiece of the present invention includes a preparatory step, an aging forming step, and an out-of-mold aging step.

The preparatory step is to prepare an aluminum alloy raw material, a mold, and a handling device. The transport device includes a moving mechanism for moving in at least one degree of freedom, and a temperature control module detachably connected to the moving mechanism.

The aging forming step includes a heating sub-step, a moving sub-step, and a forming cooling sub-step. The heating sub-step is to heat the aluminum alloy raw material to a first temperature lower than the solid solution temperature and higher than the solid solution temperature in the G-P region. In the moving sub-step, the transfer device transfers the aluminum alloy material to the mold while maintaining a second temperature through the temperature control module. Wherein, the second temperature is lower than the solid solution temperature and higher than the solid solution temperature in the G-P region. The forming cooling sub-step is to form the aluminum alloy material into a molded product while the mold is cooling.

The out-of-mold aging step is to remove the molded product from the mold, then heat the molded product to a third temperature lower than the solid solution temperature and higher than the solid solution temperature in the G-P region, and then make the aluminum alloy after another aging treatment. alloy workpiece.

The effect of the present invention is that: the aluminum alloy material can be kept at an appropriate temperature and moved to the mold through the temperature control module of the conveying device, which not only solves the problem that the temperature is easy to drop, but also avoids the time-consuming reheating The heating temperature of the aluminum alloy material is significantly lower than the thermoforming temperature, which can reduce the heat accumulation generated by the mold under mass production, prolong the service life of the mold and reduce production costs, and the aluminum alloy workpiece is matched with the baking process such as paint Subsequent treatment and the second aging treatment can achieve peak strength while completing the subsequent treatment, which is very beneficial to efficient production in terms of operating time and aging cost.

Before the present invention is described in detail, it should be noted that in the following description, similar elements are denoted by the same numerals.

Referring to FIG. 1 , it is a first embodiment of the method for forming an aluminum alloy workpiece according to the present invention. This first embodiment includes a preparatory step 11 , an aging forming step 12 , and an out-of-mold aging step 13 .

1 and 2, the preparatory step 11 is to prepare an aluminum alloy raw material, a mold for press forming, and a handling device 2 for handling the aluminum alloy material. As shown in Figure 2, the transport device 2 includes a moving mechanism 21 for moving in at least one degree of freedom, a temperature control module detachably connected to the moving mechanism 21 and used to maintain the temperature of the aluminum alloy material 22, and a fixture 29 for clamping the aluminum alloy material. Wherein, the aluminum alloy raw material in this first embodiment is the aluminum alloy AA7075 that has undergone necessary pre-aging treatment in advance, and the aluminum alloy material is made into a plate such as an automobile sheet metal as an example for illustration . The moving mechanism 21 and the temperature control module 22 can be connected to or separated from each other through control, so as to facilitate the arrangement of related configurations for automatic operations.

Referring to FIGS. 1 to 3 at the same time, the aging forming step 12 includes a heating sub-step 121 , a moving sub-step 122 , and a forming cooling sub-step 123 . Wherein, the heating sub-step 121 is to heat the aluminum alloy raw material to a first temperature lower than the solid solution temperature T1 and higher than the solvus temperature T2 of the G-P zone (Guinier Preston Zone) at a rate exceeding 10°C per second. , and maintain a period of temperature holding time to reach the uniform temperature, and carry out the first aging at the same time. Specifically, if the 6 series aluminum alloy is used, the first temperature is 130-270°C; and if the 7 series aluminum alloy is used, the heating temperature is 150-250°C. In the first embodiment, the 7-series aluminum alloy whose model is AA7075 is used as an example for illustration, so the first temperature is set to 200° C. It is worth noting that the temperature holding time is preferably 2 minutes, which not only matches the time for the aluminum alloy material to reach a uniform temperature, but also prepares in advance for the heat energy required for the subsequent aging treatment. Especially when the temperature is maintained higher than the solvus temperature T2 in the G-P region, the aluminum alloy material can start to precipitate the aluminum alloy strengthening phase and initially reach the metastable phase.

The moving sub-step 122 is to use the transfer device 2 to transfer the aluminum alloy material to the mold within a transfer time while maintaining a second temperature by the temperature control module 22 . Wherein, the second temperature is lower than the solid solution temperature T1 and higher than the solid solution temperature T2 in the G-P region, and the sum of the temperature holding time and the handling time is 5 to 300 seconds, and the main purpose is to make the aluminum alloy material enter the The mold prevents the temperature of the aluminum alloy material from dropping outside, and ensures that the aluminum alloy material can maintain a certain formability when it enters the mold, thereby optimizing the quality of forming. It should be noted that after the aluminum alloy material is placed in the mold, the mold clamping must be completed as soon as possible to prevent the temperature of the aluminum alloy material from dropping after leaving the temperature control module 22 .

The forming cooling sub-step 123 is to keep the aluminum alloy material in the mold for more than 5 seconds, so that the aluminum alloy material can be formed into the desired shape under the condition of good formability, and while cooling in the mold Formed into a molded product. That is, the aluminum alloy material is formed within aging in the forming cooling sub-step 123 .

The out-of-mold aging step 13 is to remove the molded product from the mold, then heat the molded product to a third temperature lower than the solid solution temperature T1 and higher than the solid solution temperature T2 in the G-P region, and then produce the molded product after another aging treatment. into the aluminum alloy workpiece. Specifically, since the first embodiment is described as an example of a plate made of automobile sheet metal, the out-of-mold aging step 13 is preferably compatible with the subsequent paint-baking process that will inevitably be performed. Among them, the aging temperature is 185°C, and the time for the second aging treatment is 20 minutes, which is suitable for the condition of 185°C/20 minutes in the baking process. It can directly reach the strengthening phase of the top strength when the paint is finished, so as to avoid the loss of the top strength achieved after another aging treatment due to the subsequent execution of the paint process.

Therefore, the aluminum alloy workpiece manufactured by the first embodiment can maintain the peak strength after the paint-baking process in addition to the cooperation between the aging timing and the heating process. It not only makes good use of the heat energy of the baking process, but also saves a lot of heat energy compared to the traditional heating condition of 120°C/24 hours. In addition, due to the lower target forming temperature, the mold is less prone to heat accumulation caused by frequent contact with materials or mass production, effectively increasing the service life of the mold.

Referring to Fig. 4 and Fig. 5, it is a second embodiment of the method for forming and manufacturing an aluminum alloy workpiece according to the present invention. The difference between this second embodiment and the first embodiment is that in the preparatory step 11, the prepared The aluminum alloy material is completely without any aging treatment (F state material), so the preparatory step 11 includes a pretreatment sub-step of heating the aluminum alloy material to the solid solution temperature T1 and maintaining it for a period of time, and then quenching 111. In addition, in the heating sub-step 121, because the aluminum alloy material has not undergone pre-aging treatment, compared with the first embodiment, it must undergo further heat treatment to ensure the strengthening of the structure, so it is within 20 minutes Slowly heat to the first temperature within a certain period of time, and the temperature holding time is 5 minutes.

The second embodiment is mainly for the aluminum alloy material that has not been subjected to aging treatment at all. After the pretreatment sub-step 111 , it is preferable to perform the heating sub-step 121 within 30 minutes. In the heating sub-step 121, relatively slow heating is required, and the temperature holding time is relatively long, so as to ensure that the aluminum alloy material can reach a similar pre-aging treatment before the forming cooling sub-step 123. state. Except for the above differences, the second embodiment can achieve the same effects as the first embodiment.

Referring to Fig. 6 and cooperating with Fig. 4, if the different aluminum alloy materials must be processed respectively by the first embodiment and the second embodiment, as shown in Fig. 6, a The solid solution heating furnace zone Z1 of sub-step 111, and a warm forming heating furnace zone Z2 for performing the heating substep 121, and multiple One of the handling devices 2 is used to achieve a production line configuration, optimize the efficiency of the overall process, and facilitate mass production.

To sum up, in the forming and manufacturing method of the aluminum alloy workpiece of the present invention, the aluminum alloy material combines the moving and heating process of pre-aging treatment, specifically, through the temperature control module 22 of the handling device 2, it can Maintaining the temperature required for aging treatment and moving to the mold, in addition to maintaining good formability and optimizing the forming quality, it is also possible to more flexibly arrange the aging treatment time of the aluminum alloy material. In addition, forming and cooling can be completed in the mold at the same time, and then aging treatment is carried out in conjunction with the subsequent treatment such as the baking process, and the top strength can be achieved while completing the necessary subsequent treatment. The consideration of time and efficiency cost is also very conducive to efficient production. Therefore, can really reach the purpose of the present invention.

But what is described above is only an embodiment of the present invention, and should not limit the scope of the present invention. All simple equivalent changes and modifications made according to the patent scope of the present invention and the content of the patent specification are still within the scope of the present invention. Within the scope covered by the patent of the present invention.

11: Preliminary steps 111: Preprocessing sub-step 12: Aging forming step 121: heating sub-step 122: Move sub-step 123: forming cooling sub-step 13: Out-of-mold aging steps 2: Handling device 21: Mobile Mechanism 22:Temperature control module 29: Fixture T1: solid solution temperature T2: G-P region solid solution temperature Z1: solid solution heating furnace zone Z2: Warm forming heating furnace zone

Other features and effects of the present invention will be clearly presented in the implementation manner with reference to the drawings, wherein: Fig. 1 is a block flow chart, illustrates one of first embodiment of the forming manufacturing method of aluminum alloy workpiece of the present invention; Fig. 2 is a perspective view illustrating a handling device used in a moving sub-step of an aging forming step of the first embodiment; Fig. 3 is a graph illustrating the temperature change of processing an aluminum alloy material with the first embodiment; Fig. 4 is a block flow chart, illustrates one of the second embodiment of the forming method of aluminum alloy workpiece of the present invention; Fig. 5 is a graph illustrating the temperature change of processing an aluminum alloy material with the second embodiment; and FIG. 6 is a schematic plan view illustrating a production line configuration for performing a pretreatment sub-step of one of the preparatory steps and a heating sub-step of the aging forming step of the second embodiment.

11: Preliminary steps

12: Aging forming step

121: heating sub-step

122: Move sub-step

123: forming cooling step

13: Out-of-mold aging steps

Claims (10)

A method for forming and manufacturing an aluminum alloy workpiece, comprising: A preparatory step, preparing an aluminum alloy raw material, a mold, and a handling device, the handling device includes a moving mechanism for moving in at least one degree of freedom, and a temperature control mold detachably connected to the moving mechanism Group; an aging forming step comprising A heating sub-step, heating the aluminum alloy raw material to a first temperature lower than the solid solution temperature and higher than the solvus temperature in the G-P region, A moving sub-step, using the transport device to transport the aluminum alloy material to the mold while maintaining a second temperature by the temperature control module, wherein the second temperature is lower than the solid solution temperature and higher than G-P the regional solvus temperature, and A forming cooling sub-step, forming the aluminum alloy material into a molded product while the mold is cooling; and An out-of-mold aging step, moving the molded product out of the mold, heating the molded product to a third temperature lower than the solid solution temperature and higher than the solvus temperature in the G-P region, and completing another aging treatment to produce the Aluminum alloy workpiece. The method for forming and manufacturing an aluminum alloy workpiece according to claim 1, wherein the aluminum alloy raw material in the preliminary step has been pre-aged. The method for forming and manufacturing an aluminum alloy workpiece according to claim 2, wherein, in the heating step, heating is performed to the heating temperature at a rate exceeding 10° C. per second. The method for forming and manufacturing an aluminum alloy workpiece as described in any one of claim 2 or 3, wherein, in the heating sub-step, the temperature is maintained for a period of time, and in the moving sub-step, the temperature is maintained for a period of time, and the temperature is maintained for a period of time. The total of the time and the transfer time is 5 to 300 seconds. The method for forming and manufacturing an aluminum alloy workpiece according to claim 1, wherein the preparatory step includes a pretreatment substep of heating the aluminum alloy raw material to a solid solution temperature and maintaining it for a period of time, and then quenching. The method for forming and manufacturing an aluminum alloy workpiece as described in Claim 5, wherein, in the heating sub-step, heating to the first temperature takes 10 to 30 minutes. The method for forming and manufacturing an aluminum alloy workpiece as described in any one of claim 5 or 6, wherein, in the heating sub-step, the temperature is maintained for a certain period of time, and in the moving sub-step, the temperature is maintained for a certain period of time, and the sustained temperature is maintained for a period of time. The sum of the warming time and the transfer time is 5 to 20 minutes. The method for forming and manufacturing an aluminum alloy workpiece as described in Claim 1, wherein, in the heating sub-step, the first temperature is 130-270°C. The method for forming and manufacturing an aluminum alloy workpiece as described in Claim 1, wherein, in the step of out-of-mold aging, the third temperature is 170-190°C. The forming and manufacturing method of an aluminum alloy workpiece as claimed in claim 1, wherein the moving mechanism and the temperature control module can be connected or separated from each other through control.

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