FROZEN FORMING METHOD FOR LARGE TAILORED PLATE ALUMINUM ALLOY COMPONENT

Abstract

A frozen forming method for a large-size thin-walled aluminum alloy component using an aluminum alloy tailor-welded plate is described. An aluminum alloy tailor-welded plate is cooled to a temperature with a cryogenic fluid medium, and temperature of a weld zone is regulated to be lower than that of a base metal zone; and the component is fabricated by a tool integrally with aluminum alloy tailor-welded plate, by placing aluminum alloy tailor-welded plate onto tool; assembling tool and filling with cryogenic fluid medium so temperature of tool is 150 to 196 degrees Celsius; and apply pressure to deform the aluminum alloy tailor-welded plate when temperature of a weld zone reaches 150 degrees Celsius to 196 degrees Celsius, thereby facilitating forming the aluminum alloy tailor-welded plate to a designed shape of the aluminum alloy component; and disassembling the tool, and taking out the aluminum alloy component.

Claims

1. A frozen forming method for an aluminum alloy component, comprising of: cooling an aluminum alloy tailor-welded plate with a cryogenic fluid medium, and forming the aluminum alloy plate into a complex shape component by a tool, and the frozen forming method further comprising the steps of: step 1, placing the aluminum alloy tailor-welded plate onto the tool; step 2, assembling the tool and filling the tool with the cryogenic fluid medium so that the temperature of the tool drops to 150 degrees Celsius to 196 degrees Celsius; step 3, deforming the aluminum alloy tailor-welded plate by applying pressure with the tool when the temperature of a weld zone of the aluminum alloy tailor-welded plate reaches 150 degrees Celsius to 196 degrees Celsius and is lower than the temperature of a base metal zone, that is a temperature difference delta T occurs between the weld zone and the base metal zone, thereby forming the aluminum alloy tailor-welded plate to a designed shape of the aluminum alloy component; and step 4, disassembling the tool, and taking out the aluminum alloy component.

2. The frozen forming method for the aluminum alloy component structure of claim 1, wherein in the step 3 the temperature difference between the weld zone and the base metal zone is not less than 30 degrees Celsius.

3. The frozen forming method for the aluminum alloy component of claim 2, wherein the aluminum alloy tailor-welded plate is one of an AlCuMg alloy plate, an AlCuMn alloy plate, an AlMgSi alloy plate, an AlZnMgCu alloy plate and an AlCu-Li alloy plate.

4. The frozen forming method for the aluminum alloy component of claim 2, wherein the aluminum alloy tailor-welded plate is prepared by friction stir welding technology.

5. The frozen forming method for the aluminum alloy component of claim 4, wherein the cryogenic fluid medium is a cooling medium for cryogenic temperature, and is either liquid nitrogen or liquid helium.

6. The frozen forming method for the aluminum alloy component of claim 1, wherein a solution treatment is conducted on the aluminum alloy tailor-welded plate before the step 1, and an artificial aging treatment is conducted on the aluminum alloy component after the step 4.

7. The frozen forming method for the aluminum alloy component claim 1, wherein the tool comprises at least one cooling chamber, and the cooling chamber is disposed as a portion of the tool, where the weld zone is located, and is used for cooling.

8. The frozen forming method for the aluminum alloy component claim 7, wherein in the step 2, the temperature of the tool is regulated via a control device, and the control device is connected with the cooling chamber, and further controlling of the temperature of the cooling chamber is by regulating the flow of the cryogenic fluid medium.

9. The frozen forming method for the aluminum alloy component of claim 8, wherein the tool is further provided with a thermal insulating layer.

10. The frozen forming method for the aluminum alloy component of claim 9, wherein the tool is provided with a cooling channel, and the cooling channel is disposed as a portion of the tool, where the weld zone of the aluminum alloy tailor-welded plate is located.

11. The frozen forming method for the aluminum alloy component of claim 4, wherein the aluminum alloy tailor-welded plate having a thickness of between 2 mm to 8 mm, and made from an aluminum alloy plate having a diameter of 2700 mm to 4200 mm.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical schemes in embodiments of the present invention, the drawings to be used in the embodiments will be simply introduced as follows.

[0022] FIG. 1 is a schematic diagram of initial status/setup of frozen forming using an aluminum alloy FSW tailor-welded plate, where a tool is provided with a cooling channel, according to an embodiment of the present invention.

[0023] FIG. 2 is a schematic diagram of initial status/setup of frozen forming for a flat-bottom cylindrical component using the aluminum alloy FSW tailor-welded plate in embodiment of Example 1 of the present invention;

[0024] FIG. 3 is a schematic diagram of final status of frozen forming for a flat-bottom cylindrical component using the aluminum alloy FSW tailor-welded plate in Example 1 of the present invention;

[0025] FIG. 4 is a schematic diagram of a flat-bottom cylindrical component structure by frozen forming using the aluminum alloy FSW tailor-welded plate in Example 1 of the present invention;

[0026] FIG. 5 is a schematic diagram of initial status/step of frozen forming for a hemispherical component using an aluminum alloy FSW tailor-welded plate in Example 3 of the present invention;

[0027] FIG. 6 is a schematic diagram of final status of frozen forming for the hemispherical component structure using the aluminum alloy FSW tailor-welded plate in Example 3 of the present invention;

[0028] FIG. 7 is a hemispherical component structure diagram by frozen forming using the aluminum alloy FSW tailor-welded plate in Example 3 of the present invention;

[0029] FIG. 8 is a schematic diagram of initial status of frozen forming for a -shaped component using an aluminum alloy FSW tailor-welded plate in Example 5 of the present invention;

[0030] FIG. 9 is a schematic diagram of final status of frozen forming for a -shaped component using the aluminum alloy FSW tailor-welded plate in Example 5 of the present invention;

[0031] FIG. 10 is an -shaped component structure fabricated by frozen forming using the aluminum alloy FSW tailor-welded plate in Example 5 of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0032] The above-mentioned and other technical features and advantages of the present invention will be further described in detail below in conjunction with the accompanying drawings.

[0033] Please refer to FIG. 1. FIG. 1 is a schematic diagram of initial status, or setup of cryogenic/freezing forming using an aluminum alloy friction stir welding (FSW) tailor-welded plate, where a tool is provided with a cooling channel, according to an embodiment of the present invention.

[0034] The present invention provides a first embodiment of a frozen forming method for an aluminum alloy tailor-welded component structure. An aluminum alloy tailor-welded plate 4 is prepared by friction stir welding (FSW) technology. The frozen forming method according to a first embodiment of the present invention is as follows: the aluminum alloy tailor-welded plate 4 is cooled to a temperature within an appropriate very low temperature range with a cryogenic fluid medium, and a aluminum alloy tailor-welded flat bottom cylindrical component 7 is formed by a tool. For the sake of simplicity, the aluminum alloy tailor-welded flat bottom cylindrical component 7 is also referred to as the aluminum alloy tailor-welded component 7 in the following descriptions.

[0035] The additional/further specific steps for the frozen forming method in example 1 are as follows in these steps: step 1, the aluminum alloy tailor-welded plate is placed onto the tool; [0036] step 2, the tool is assembled and filled with the cryogenic fluid medium so that the temperature of the tool drops to 150 degrees Celsius to 196 degrees Celsius; step 3, the tool is allowed to apply pressure to deform the aluminum alloy tailor-welded plate when the temperature of a weld zone 42 of the aluminum alloy tailor-welded plate reaches 150 degrees Celsius to 196 degrees Celsius and the temperature of the weld zone 42 is lower than the temperature of a base metal zone 41, that is a temperature difference delta T occurs between the weld zone 42 and the base metal zone 41, thereby forming the aluminum alloy tailor-welded component 7; and step 4, the tool assembled in the step 2 is now disassembled, and the aluminum alloy tailor-welded component 7 is taken out, thereby completing the frozen forming of the aluminum alloy tailor-welded component 7.

[0037] The frozen forming method for the large-size aluminum alloy tailor-welded component involves a frozen forming device. The frozen forming device includes a set of tool (not labelled, but shown in FIGS. 1-3, respectively); the tool includes a punch 33, a die 31, a blank holder 32; the die 31 is disposed at a lower portion of the tool; the blank holder 32 is disposed at a middle portion of the tool; and the die 33 is disposed at an upper portion of the tool and is used for applying pressure to the aluminum alloy tailor-welded plate 4 so as to facilitate the forming of the aluminum alloy tailor-welded plate 4. Moreover, a first thermal insulation layer 61 and a second thermal insulation layer 62 are disposed in the tool so as to reduce cold/thermal exchange or cold/thermal conduction between the tool and the outside, thus avoiding loss of refrigeration capacity, and improving the cooling effect of the tool. Moreover, a groove 35 is reserved at a contact surface of the tool and the aluminum alloy tailor-welded plate 4, and is used for storing ice, thus can be also called an ice groove. Moreover, a cooling chamber 34 is disposed in a portion of the tool, disposed at below the weld zone 42 of the aluminum alloy tailor-welded plate 4, of the die 31, and is used for cooling.

[0038] The frozen forming device further includes a first temperature sensor 51, a second temperature sensor 52, a cryogenic fluid medium storage tank 2 and a control device (not labeled); the first temperature sensor 51 and the second temperature sensor 52 are used for monitoring the temperature of the weld zone 42 and the temperature of the base metal zone 41, respectively; the cryogenic fluid medium storage tank 2 is used for storing the cryogenic fluid medium; the control device includes a first control valve 11 and a second control valve 12 which are connected with the cryogenic fluid medium storage tank 2 and the cooling chamber 34, respectively, and used for regulating a flow of the cryogenic fluid medium to further control the temperature of the cooling chamber 34.

[0039] As a preferred embodiment, a cooling channel 8 is disposed in the tool and the cooling channel 8 is disposed below the aluminum alloy tailor-welded plate 4, so that the cryogenic fluid medium is prevented from being in direct contact with the aluminum alloy tailor-welded plate 4, evaporation and loss of the cryogenic fluid medium are reduced, and the cryogenic fluid medium can be recycled in the (sealed) cooling channel 8 conveniently.

EXAMPLE 1

[0040] Please refer to FIG. 2, FIG. 3 and FIG. 4. FIG. 2 is a schematic diagram of initial status/setup of frozen forming for a flat-bottom cylindrical component 7 using the aluminum alloy (FSW) tailor-welded plate 4 in this illustrated example 1; For the sake of simplicity, the tailor-welded flat bottom cylindrical component 7 is also called the aluminum alloy tailor-welded component 7 and the flat-bottom cylindrical component 7 in the following descriptions. FIG. 3 is a schematic diagram of final status of frozen forming method for the flat-bottom cylindrical component 7 using the aluminum alloy (FSW) tailor-welded plate 4 in this example 1; FIG. 4 shows a flat-bottom cylindrical component 7 fabricated by frozen forming using the aluminum alloy FSW tailor-welded plate 4 in this example 1; The example 1 provides a freeze-forming method for a flat-bottom cylindrical component 7 using the aluminum alloy FSW tailor-welded plate 4 which is of a large-size, wherein an aluminum alloy plate is an AlCuMn alloy, and particularly an annealing status 2219 aluminum alloy tailor-welded plate with a thickness of 6 mm. Parameters for friction stir welding performed on the aluminum alloy plate are as follows: the welding advancing speed is 300 mm/min and the welding rotating speed is 800 rpm; and the diameter of a circular blank is 2700 mm and one weld joint is located at a symmetric axis of the aluminum alloy plate. A flat-bottom cylindrical rigid tool with the diameter of 2250 mm is adopted, and includes a die 33, a punch 31 and a blank holder 32, wherein a cooling chamber 34 is preset in the die 31. The additional/further specific steps for the frozen forming process while above friction stir welding process is also performed on the aluminum alloy plate are as follows: [0041] step 1, placing the 2219 aluminum alloy tailor-welded plate 4 onto the tool and allowing a weld zone 42 to be located above the cooling chamber 34 of the die; [0042] step 2, filling the cooling chamber 34 of the die with the cryogenic fluid medium so that the temperature of the cooling chamber 34 of the die drops to 150 degrees Celsius; [0043] step 3, assembling the blank holder 32 and the punch 33, allowing the blank holder 32 to apply pressure of 3 MPa, regulating the flow of the cryogenic fluid medium through the first control valve 11 and the second control valve 12, and allowing the punch 33 to descend to apply drawing force to deform the 2219 aluminum alloy tailor-welded plate 4 when the temperature of the weld zone 42 of the 2219 aluminum alloy tailor-welded plate 4 reaches 150 degrees Celsius and the temperature of the base metal zone 41 is higher than 120 degrees Celsius, thereby forming a flat-bottom cylindrical component 7 using the 2219 aluminum alloy tailor-welded plate 4; and [0044] step 4, separating the punch 33, the blank holder 32 and the die 31, and taking out the flat-bottom cylindrical component 7 deformed using the 2219 aluminum alloy tailor-welded plate 4, thereby completing the frozen forming process of the 2219 aluminum alloy tailor-welded plate (that is also prepared by a concurrent friction stir welding process) for fabricating a flat-bottom cylindrical component 7. The cryogenic fluid medium is a very low temperature cooling medium, and is either liquid nitrogen or liquid helium.

[0045] By utilizing the feature that the plasticity and the strength of the weld zone are higher than the plasticity and the strength of the base metal zone caused by temperature difference on the aluminum alloy tailor-welded plate, the aluminum alloy tailor-welded plate can be deformed at a very low temperature. So, the cracking problem caused by a high degree of deformation in the weld zone can be avoided; the flat-bottom cylindrical component formed using the aluminum alloy tailor-welded plate in the example 1 can avoid microstructure damage and restore to original microstructure status after being formed, the mechanical property of the flat-bottom cylindrical component is basically not changed by the forming at the very low cryogenic temperature range. In the example 1 of freeze-forming process of the flat-bottom cylindrical component with aluminum alloy tailor-welded plate, frozen lubricating layers are formed at working surfaces between the tailor-welded plate and the tool, which can reduce friction force during flowing of the blank while the performing the FSW process, thereby reducing forming force, and greatly reducing the tonnage and cost of forming equipment.

EXAMPLE 2

[0046] This example provides a frozen forming method for a flat-bottom cylindrical component structure, also referred to as flat-bottom cylindrical component herein below, using an aluminum alloy FSW tailor-welded plate, and differs from Example 1 in that the aluminum alloy plate is an AlCuMg alloy, and particularly an annealing status 2024 aluminum alloy tailor-welded plate with a thickness of 7 mm. Parameters for friction stir welding performed on the aluminum alloy plate are as follows: the welding advancing speed is 200 mm/min and the welding rotating speed is 1000 rpm; and the diameter of a circular blank is 2700 mm and one weld joint is located at a symmetric axis of the aluminum alloy plate. A flat-bottom cylindrical rigid tool with the diameter of 2250 mm is adopted, and includes a punch 33, a die 31 and a blank holder 32, wherein a cooling chamber 34 is preset in the die 31. The further specific steps for the frozen forming process of example 2 are as follows: [0047] step 1, placing the 2024 aluminum alloy tailor-welded plate 4 onto the tool and allowing a weld zone 42 to be located above the cooling chamber 34 of the die; [0048] step 2, filling the cooling chamber 34 of the die with a cryogenic fluid medium so that the temperature of the cooling chamber 34 of the die drops to 172 degrees Celsius; [0049] step 3, assembling the blank holder 32 and the punch 33, allowing the blank holder 32 to apply 3 MPa pressure, regulating the flow of the cryogenic fluid medium through the first control valve 11 and the second control valve 12, and allowing the punch 33 to descend to apply drawing force to deform the 2024 aluminum alloy tailor-welded plate 4 when the temperature of the weld zone 42 of the 2024 aluminum alloy tailor-welded plate 4 reaches 172 degrees Celsius and the temperature of the base metal zone 41 is higher than 142 degrees Celsius, thereby forming a flat-bottom cylindrical component 7 using the 2024 aluminum alloy tailor-welded plate 4; and [0050] step 4, separating the punch 33, the blank holder 32 and the die 31, and taking out the flat-bottom cylindrical component 7, thereby completing frozen forming of the flat-bottom cylindrical component 7 of the 2024 aluminum alloy tailor-welded plate 4. The cryogenic fluid medium is a very low temperature cooling medium, and is either liquid nitrogen or liquid helium, for example.

[0051] By utilizing the feature that the plasticity and the strength of the weld zone are higher than the plasticity and the strength of the base metal zone caused by temperature difference on the aluminum alloy tailor-welded plate, the cracking problem caused by a high degree of deformation in the weld zone can be avoided. The flat-bottom cylindrical component of aluminum alloy tailor-welded plate formed in the example can avoid microstructure damage and restore to original microstructure status after being formed, the microstructure and mechanical property are basically not changed by the forming at the very low temperature; and in the example of frozen forming process for flat-bottom cylindrical component with the aluminum alloy tailor-welded plate, frozen lubricating layers are formed at working surfaces between the tailor-welded plate and the tool, which can reduce frictional force during flowing of the blank, reduce forming force, and greatly reduce the tonnage and cost of forming equipment.

EXAMPLE 3

[0052] Please refer to FIG. 5, FIG. 6 and FIG. 7. FIG. 5 is a schematic diagram of initial status of frozen forming for a hemispherical (aluminum alloy tailor-welded) component 7 using an aluminum alloy FSW tailor-welded plate in Example 4 of the present invention; FIG. 6 is a schematic diagram of final status of frozen forming for the hemispherical (aluminum alloy tailor-welded) component 7 using the aluminum alloy FSW tailor-welded plate in Example 4 of the present invention; FIG. 7 shows a hemispherical (aluminum alloy tailor-welded) component 7 fabricated by frozen forming using the aluminum alloy FSW tailor-welded plate in Example 4 of the present invention The example 3 provides a frozen forming method for a hemispherical component using an aluminum alloy FSW tailor-welded plate, wherein an aluminum alloy plate is an AlCuMn alloy, and particularly an annealing status 2219 aluminum alloy tailor-welded plate with the thickness of 8 mm. Parameters for friction stir welding performed on the aluminum alloy plate are as follows: the welding advancing speed is 300 mm/min and the welding rotating speed is 800 rpm; the diameter of a circular blank is 4200 mm; two weld joints are located at two sides, 1750 mm far away from a symmetric axis of the blank respectively; and a semi-ellipsoidal rigid tool with the diameter of 3350 mm is adopted, and includes a punch 33, a die 31 and a blank holder 32, wherein cooling chambers 34 are preset in the die 31. The further specific steps for frozen forming method for example 3 are as follows: [0053] step 1, conducting solution treatment on the aluminum alloy tailor-welded plate 4, heating a solid solution to 535 degrees Celsius by a box type heating furnace, placing in the aluminum alloy tailor-welded plate 4 for heat preservation for 45 minutes, then taking the aluminum alloy tailor-welded plate 4 out and conducting rapid water quenching on the aluminum alloy tailor-welded plate 4; [0054] step 2, placing the 2219 aluminum alloy tailor-welded plate 4 onto the tool and allowing weld zones 42 to be located above the cooling chambers 34 of the die; [0055] step 3, filling the cooling chambers 34 of the die with the cryogenic fluid medium so that the temperatures of the cooling chambers 34 of the die drop to 180 degrees Celsius; [0056] step 4, assembling the blank holder 32 and the punch 33, allowing the blank holder 32 to apply pressure of 3 MPa, regulating the flow of the cryogenic fluid medium through the first control valve 11 and the second control valve 12, and allowing the punch 33 to descend to apply drawing force to deform the 2219 aluminum alloy tailor-welded plate 4 when the temperatures of the weld zones 42 of the 2219 aluminum alloy tailor-welded plate 4 reach 180 degrees Celsius and the temperature of the base metal zone 41 is higher than 150 degrees Celsius, thereby forming a hemispherical (aluminum alloy tailor-welded) component 7 using the 2219 aluminum alloy tailor-welded plate 4; [0057] step 5, separating the punch 33, the blank holder 32 and the die 31, and taking out the hemispheric component 7, thereby completing frozen forming of hemispheric component 7 with the 2219 aluminum alloy tailor-welded plate 4; and [0058] step 6, conducting artificial aging treatment on the (thin-walled) hemispherical component 7, placing the hemispherical component 7 in an aging furnace for heat preservation at 175 degrees Celsius for 18 hours, then taking the hemispherical component 7 out, and air cooling the hemispherical component to the room temperature. The cryogenic fluid medium is a very low temperature cooling medium, and is either liquid nitrogen or liquid helium.

[0059] By utilizing the feature that the plasticity and the strength of the weld zone are higher than the plasticity and the strength of the base metal zone caused by temperature difference on aluminum alloy tailor-welded plate at a very low temperature, the cracking problem caused by high degrees of deformation in the weld zones can be avoided and restore to original microstructure status after being formed. The aluminum alloy tailor-welded plate hemispheric component formed in the example can avoid microstructure damage and restore to original microstructure status after being formed, the microstructure and mechanical property are basically not changed by the forming at the very low temperature. In the example of the freeze-forming process of the hemispheric component, frozen lubricating layers are formed at working surfaces between the tailor-welded plate and the tool, which can reduce friction force during flowing of the blank, reduce forming force, and greatly reduce the tonnage and cost of forming equipment.

EXAMPLE 4

[0060] This example provides a frozen forming method for a hemispherical shaped component (structure) fabricated from an aluminum alloy FSW tailor-welded plate, and differs from Example 3 in that wherein an aluminum alloy plate is an AlMgSi alloy, and particularly a quenching status 6016 aluminum alloy tailor-welded plate with the thickness of 6 mm. Parameters for friction stir welding performed on the aluminum alloy plate are as follows: the welding advancing speed is 400 mm/min and the welding rotating speed is 1200 rpm; the diameter of a circular slab is 4200 mm; two weld joints are located at two sides, 1750 mm far away from a symmetric axis of the slab respectively; and a semi-ellipsoidal rigid tool with the diameter of 3350 mm is adopted., and includes a punch 33, a die 31 and a blank holder 32, wherein a plurality of cooling chambers 34 are preset in the die 31. The further specific steps for frozen forming method in example 4 are as follows: step 1, placing the 6016 aluminum alloy tailor-welded plate 4 onto the tool and allowing weld zones 42 to be located above the cooling chambers 34 of the die; step 3, filling the cooling chambers 34 of the die with the cryogenic fluid medium so that the temperatures of the cooling chambers 34 of the die drop to 160 degrees Celsius; step 4, assembling the blank holder 32 and the punch 33, allowing the blank holder 32 to apply pressure of 3 MPa, regulating the flow of the cryogenic fluid medium through the first control valve 11 and the second control valve 12, and allowing the punch 33 to descend to apply drawing force to deform the 6016 aluminum alloy tailor-welded plate 4 when the temperatures of the weld zones 42 of the 6016 aluminum alloy tailor-welded plate 4 reach 160 degrees Celsius and the temperature of the base metal zone 41 is higher than 130 degrees Celsius, thereby forming a 6016 aluminum alloy tailor-welded plate hemispherical component; step 5, separating the punch 33, the blank holder 32 and the die 31, and taking out the hemispherical component, thereby completing the frozen forming of the hemispherical component 7; and step 6, conducting artificial aging treatment on the (thin-walled) hemispherical component 7, and placing the hemispherical component 7 in an aging furnace for heat preservation at 175 degrees Celsius for 20 minutes, then taking the hemispherical component 7 out and air cooling the hemispherical component 7 to the room temperature. The cryogenic fluid medium is a very low temperature cooling medium, and is either liquid nitrogen or liquid helium.

[0061] By utilizing the feature that the plasticity and the strength of the weld zone are higher than the plasticity and the strength of the base metal zone, caused by temperature difference on aluminum alloy tailor-welded plate at a very low temperature, the cracking problem caused by high degrees of deformation in the weld zones can be avoided and restore to original microstructure status after being formed. The hemispheric component formed using aluminum alloy tailor-welded plate in the example can avoid internal microstructure damage, the structure property is basically not changed by the forming at the very low temperature. In the example of the freeze-forming process of hemispheric component with the aluminum alloy tailor-welded plate, frozen lubricating layers are formed at working surfaces between the tailor-welded plate and the tool, which can reduce frictional resistance during flowing of the blank, reduce forming force, and greatly reduce the tonnage and cost of forming equipment.

[0062] Example 5 Please refer to FIG. 8, FIG. 9 and FIG. 10 for illustrating of Example 5. FIG. 8 is a schematic diagram of initial status of frozen forming for an -shaped component with an aluminum alloy FSW tailor-welded plate in this example; FIG. 9 is a schematic diagram of final status of frozen forming for an -shaped component with the aluminum alloy FSW tailor-welded plate in this example; FIG. 10 is an -shaped component structure diagram of freeze-forming of the aluminum alloy FSW tailor-welded plate in this example. The example provides a frozen forming method of an -shaped component with an aluminum alloy FSW tailor-welded plate, wherein an aluminum alloy plate is an AlCuLi alloy, and particularly an annealing status 2195 aluminum alloy tailor-welded plate with the thickness of 2 mm. Parameters for friction stir welding are as follows: the welding advancing speed is 200 mm/min and the welding rotating speed is 1000 rpm; the size of a rectangular slab is 1200 mm (L)600 mm (W); three weld joints are respectively located at a center of a symmetric axis in the width direction of the blank, and at two sides, 200 mm far away from the symmetric axis; and a rigid tool with the length, width and height of 1200 mm, 300 mm and 300 mm respectively is adopted, and includes a punch 33, a die 31 and a blank holder 32, wherein cooling chambers 34 are preset in the die 31. The further specific steps for example 5 are as follows: [0063] step 1, placing the 2195 aluminum alloy tailor-welded plate 4 onto the tool and allowing weld zones 42 to be located above the cooling chambers 3-4 of the die; [0064] step 2, filling the cooling chambers 34 of the die with the cryogenic fluid medium so that the temperatures of the cooling chambers 34 of the die drop to 196 degrees Celsius; [0065] step 3, assembling the blank holder 32 and the punch 33, allowing the blank holder 32 to apply pressure of 3 MPa, regulating the flow of the cryogenic fluid medium through the first control valve 11 and the second control valve 12, and allowing the punch 33 to descend to apply drawing force to deform the 2195 aluminum alloy tailor-welded plate 4 when the temperatures of the weld zones 42 of the 2195 aluminum alloy tailor-welded plate 4 reach 196 degrees Celsius and the temperature of the base metal zone 41 is higher than 150 degrees Celsius, thereby forming an -shaped component with 2195 aluminum alloy tailor-welded plate; and [0066] step 4, separating the punch 33, the blank holder 32 and the die 31, and taking out the -shaped component, thereby completing frozen forming of the -shaped component 7. The cryogenic fluid medium is a very low temperature cooling medium, and is either liquid nitrogen or liquid helium.

[0067] By utilizing the feature that the plasticity and the strength of the weld zone are higher than the plasticity and the strength of the base metal zone caused by temperature difference on aluminum alloy tailor-welded plate at a very low temperature, the cracking problem caused by high degrees of deformation in the weld zones can be avoided and restore to original microstructure status after being formed. The -shaped component formed using aluminum alloy tailor-welded plate in the example can avoid microstructure damage, the microstructure and mechanical property are basically not changed by the forming at the very low temperature. In the example of the frozen forming process of -shaped component with the aluminum alloy tailor-welded plate, frozen lubricating layers are formed at working surfaces between the tailor-welded plate and the tool, which can reduce frictional resistance during flowing of the blank, reduce forming force, and greatly reduce the tonnage and cost of forming equipment.

EXAMPLE 6

[0068] This example provides a frozen forming method for a flat-bottom cylindrical component with aluminum alloy FSW tailor-welded plate, and differs from Example 1 in that the aluminum alloy plate is an AlZnMgCu alloy, and particularly an aging status 7075 aluminum alloy tailor-welded plate with the thickness of 6.5 mm. Parameters for friction stir welding are as follows: the welding advancing speed is 300 mm/min and the welding rotating speed is 800 rpm; and the diameter of a circular blank is 2700 mm and one weld joint is located at a symmetric axis of the blank; and a flat-bottom cylindrical rigid tool with the diameter of 2250 mm is adopted, and includes a punch 33, a die 31 and a blank holder 32, wherein a cooling chamber 34 is preset in the die 31. The further specific steps are as follows: [0069] step 1, placing the 7075 aluminum alloy tailor-welded plate 4 onto the tool and allowing a weld zone 42 to be located above the cooling chamber 34 of the die; [0070] step 2, filling the cooling chamber 34 of the die with the cryogenic fluid medium so that the temperature of the cooling chamber 34 of the die drops to 180 degrees Celsius; [0071] step 3, assembling the blank holder 32 and the punch 33, allowing the blank holder 32 to apply pressure of 3 MPa, regulating the flow of the cryogenic fluid medium through the first control valve 11 and the second control valve 12, and allowing the punch 33 to descend to apply drawing force to deform the 7075 aluminum alloy tailor-welded plate 4 when the temperature of the weld zone 42 of the 7075 aluminum alloy tailor-welded plate 4 reaches 180 degrees Celsius and the temperature of the base metal zone 41 is higher than 150 degrees Celsius, thereby forming a 7075 aluminum alloy tailor-welded plate flat-bottom cylindrical component; and [0072] step 4, separating the punch 33, the blank holder 32 and the die 31, and taking out the 7075 aluminum alloy tailor-welded plate flat-bottom cylindrical component, thereby completing frozen forming of the 7075 aluminum alloy tailor-welded plate flat-bottom cylindrical component 7. The cryogenic fluid medium is a very low temperature cooling medium, and is either liquid nitrogen or liquid helium.

[0073] By utilizing the feature that the plasticity and the strength of the weld zone are higher than the plasticity and the strength of the base metal zone caused by temperature difference on aluminum alloy tailor-welded plate at a very low temperature, the cracking problem caused by a high degree of deformation in the weld zone can be avoided and restore to original microstructure status after being formed. The -shaped component formed using the aluminum alloy tailor-welded plate in the example can avoid microstructure damage, the microstructure and mechanical property are basically not changed by the forming at the very low temperature. In this example the frozen forming process of -shaped component with the aluminum alloy tailor-welded plate, frozen lubricating layers are formed at working surfaces between the tailor-welded plate and the tool, which can reduce friction force during flowing of the blank, reduce forming force, and greatly reduce the tonnage and cost of forming equipment.

[0074] In the above examples, the fabricated different shaped component structures or components can be classified as being of thin wall and large size based on the specific thickness and diameter values, respectively.

[0075] Although the invention is described in detail in combination with the above examples, those of ordinary skill in the art shall understood that they can modify technical schemes documented in the above examples or perform equivalent replacement on some technical features, and any modification, equivalent replacement, improvement and the like made within the spirit and rule of the invention shall be incorporated in the protection scope of the invention.