CN114147425A

CN114147425A - Method and device for preparing large-width aluminum alloy tailor-welded blank

Info

Publication number: CN114147425A
Application number: CN202111444048.8A
Authority: CN
Inventors: 凡晓波; 苑世剑
Original assignee: Dalian University of Technology
Current assignee: Dalian University of Technology
Priority date: 2021-11-30
Filing date: 2021-11-30
Publication date: 2022-03-08
Anticipated expiration: 2041-11-30
Also published as: CN114147425B

Abstract

The invention provides a method and a device for preparing a large-width aluminum alloy tailor-welded blank, which comprises the following steps: selecting a proper aluminum alloy plate blank according to the width size of the ultra-wide plate; cooling the fixed clamping plate to-40-0 ℃; simultaneously carrying out solution treatment on a plurality of aluminum alloy plate blanks to obtain solid solution plate blanks; placing a plurality of solid solution state plate blanks on a fixing clamping plate, fixing the plate blanks, butting the parts to be welded of the two plate blanks, pressing the positions close to a welding area through a pressing plate, ensuring that the plate blanks do not move relatively in the welding process, and cooling the solid solution state plate blanks to-40-0 ℃ through heat conduction of the fixing clamping plate; and finally, performing friction stir welding to enable the original solid solution state plate blank to form compact metal combination under the combined action of a heat machine and a machine so as to obtain the ultra-wide plate blank. According to the invention, the ultra-wide plate blank is prepared by friction stir welding at low temperature, so that the welding in a solid solution state can be ensured, the cooling of a welding area can be accelerated, and the problem of weakening of the structure performance of a welding seam is avoided.

Description

Method and device for preparing large-width aluminum alloy tailor-welded blank

Technical Field

The invention relates to the technical field of metal plate forming, in particular to a method and a device for preparing a large-width aluminum alloy tailor-welded blank.

Background

The aluminum alloy is a main structural material of carrying equipment such as rockets, airplanes, automobiles, high-speed rails and the like. With the great improvement of the new generation of equipment on light weight and high reliability, the aluminum alloy thin-wall part with an integral structure is urgently needed. The structural integration leads the size of the component to be larger and larger, and a large aluminum alloy thin-wall component appears, such as the diameter of the integral box bottom of a fuel storage box of a carrier rocket exceeds 3 m. The integral formation of such members necessarily requires large ultra-wide slabs of over 4.5 m.

Typically, the aluminum alloy slabs are produced by a rolling process. The rolling defects of unequal deformation of the wide width and the ultra-wide plate of the rolling mill are overcome, and the maximum plate width amplitude of a thin plate with the thickness less than 5mm can reach 2.5 m; the maximum plate width of the plate blank with larger thickness can only reach 4m, and the plate blank width required by the integral forming of large-scale components can not be met. Therefore, the ultra-wide plate blank is required to be obtained through tailor welding of a plurality of plate blanks, and how to ensure that the performance of the welding seam is consistent with that of the base metal is very important. Compared with the traditional fusion welding, the friction stir welding is a solid phase connection technology, has small welding heat input and low temperature, can avoid the defects of thick precipitated phase, air holes and the like caused by the fusion welding, is widely applied to the aluminum alloy welding, and can be used for preparing large-size ultra-wide aluminum alloy slabs.

It is worth noting that solid solution forming is often selected for the integral forming of large aluminum alloy thin-wall parts, on one hand, the solid solution forming performance is the best; on the other hand, the problem of serious shape distortion caused by quenching after forming is avoided. That is, the ultra-wide slab to be produced is finished in a solid solution state. However, the annealed plate blank is subjected to solid solution after welding, so that the abnormal growth of crystal grains occurs in the welding line in the solid solution treatment process, the performance of the welding line is weakened, and cracking is caused. The annealed plate blank is welded after solid solution, natural aging can occur in the welding process, the integral forming performance of the plate blank is reduced, and the plate blank cannot be formed. Particularly, high-strength aluminum alloys such as 2A14 and 2195 need to be formed within 2h after solid solution, and large-size ultra-wide plate blank welding is difficult to complete within a short time. What is more challenging is that the large-size ultra-wide slab not only needs the ultra-large-size friction stir welding machine, but also needs to be finished on a processing site, otherwise the ultra-wide slab is difficult to transport. The prior art can not obtain a large-size ultra-wide aluminum alloy plate blank suitable for the integral forming of a large-size thin-wall part.

Disclosure of Invention

According to the technical problem that the large-size ultra-wide aluminum alloy plate blank suitable for integral forming of a large-size thin-wall part cannot be obtained in the prior art, the method and the device for preparing the large-size ultra-wide aluminum alloy tailor-welded plate blank are provided. The invention mainly utilizes the fixing device, the welding device and the cooling device to prepare the large-size ultra-wide aluminum alloy plate blank through low-temperature friction stir welding, and solves the problem that the large-size ultra-wide aluminum alloy plate blank suitable for the integral forming of a large-size thin-wall part cannot be obtained in the prior art.

The technical means adopted by the invention are as follows:

a method for preparing a large-width aluminum alloy tailor-welded blank comprises the following steps:

the method comprises the following steps: and determining a slab. Selecting a proper aluminum alloy plate blank according to the width size of the ultra-wide plate;

step two: and (6) cooling. Cooling the fixed clamping plate to-40-0 ℃;

step three: and (5) carrying out solution treatment on the plate blank. Simultaneously carrying out solution treatment on a plurality of aluminum alloy plate blanks to obtain solid solution plate blanks;

step four: and (5) assembling, fixing and cooling the plate blank. Placing a plurality of solid solution state plate blanks on a fixing clamping plate, fixing the plate blanks, butting the parts to be welded of the two plate blanks, pressing the parts close to a welding area through a pressing plate, ensuring that the plate blanks do not move relatively in the welding process, and cooling the solid solution state plate blanks to-40-0 ℃ through heat conduction of the fixing clamping plate;

step five: and (5) stirring and friction welding. And driving a motor to enable a welding head of the friction stir welding to rotate at a constant speed, slowly inserting a stirring pin of the welding head into the plate blank, moving the welding head forwards at a constant speed along the welding direction while rotating, and forming compact metal combination on the original solid solution state plate blank under the combined action of a heat machine to obtain the ultra-wide plate blank.

Further, the aluminum alloy slab is mainly a heat-treatable strengthened aluminum alloy, such as a 2 xxx, 6 xxx or 7 xxx series aluminum alloy sheet.

Further, in the fifth step, the welding head of the friction stir welding keeps constant-speed feeding and constant-speed rotation, the feeding speed is 100 mm/min-300 mm/min, and the rotating speed is 600 r/min-1400 r/min.

The invention also provides a large-width aluminum alloy tailor-welded blank preparation device, which comprises the following steps: fixing device, installation welding set and cooling device on fixing device, fixing device is used for realizing the fixed of slab, is provided with moving mechanism on it, welding set installs on moving mechanism, moving mechanism is used for realizing welding set along the motion of welding direction, welding set is used for welding the position of treating welding between the slab, cooling device links to each other with fixing device for provide the low temperature environment, cool down to the slab.

Further, the welding device is a friction stir welding machine comprising: the welding head of the friction stir welding with proper size and the motor are arranged on the moving mechanism and used for driving the welding head to weld the parts to be welded between the plate blanks.

Further, the fixing device further includes: the single-rail gantry structure is used for installing a moving mechanism, the solid rigid body is used for placing and positioning the plate blank, and the pressing plate and the fastening bolt are used for fixing the plate blank; the gantry structure is fixed on the solid rigid body, the two plate blanks are placed on the top of the solid rigid body together, the part to be welded between the plate blanks is positioned on the solid rigid body and is pressed tightly by a pressing plate close to the part to be welded, and the pressing plate is fixed on the solid rigid body by a fastening bolt in matched connection;

the moving mechanism comprises a horizontal sliding block and a vertical sliding block, the horizontal sliding block is arranged in a guide rail of the gantry structure, the vertical sliding block is arranged in the guide rail of the horizontal sliding block, and the welding device is fixed on the vertical sliding block; the friction stir welding machine is fixed by adopting a single-rail gantry structure, the welding end part is compressed, the end part of a connecting plate blank is ensured to be in close contact through the limiting of a clamping groove, and the contact gap of the plate blank is superposed with the movement track of the welding machine.

Further, the cooling device includes: the cooling device comprises a fixed clamping plate, a cooling loop, a cooling source and a temperature control device, wherein two fixed clamping plates are respectively and fixedly connected to two sides of a solid rigid body of the fixing device and used for cooling the plate blank; the cooling source is connected with the fixed clamping plate through a cooling loop and creates a low-temperature environment by means of heat conduction; the temperature control device is connected with the cooling source and used for stabilizing the temperature of the device at a set temperature.

Furthermore, a liquid conveying pipeline communicated with a cooling loop is arranged inside the fixing clamping plate, a cooling source conveys low-temperature media into the liquid conveying pipeline through the cooling loop, the fixing clamping plate is cooled to a set temperature, and the fixing clamping plate creates a low-temperature environment for the plate blank by means of heat conduction;

the temperature control device adopts feedback adjustment, and a low-temperature thermocouple is fixed on the fixing clamping plate and used for measuring the temperature of the substrate in real time; the flow velocity of the low-temperature medium is controlled according to the real-time temperature of the fixing clamping plate, so that the temperature of the device is stabilized at a set temperature, and the cooling function is realized.

Furthermore, the fixing clamping plate and the solid rigid body adopt a box-type combined structure, the solid rigid body is adopted only in a welding area needing supporting force, and cooling boxes are adopted in other cooling areas; a communication pipeline communicated with the cooling loop is arranged in the solid rigid body, and the fixed clamping plate and the solid rigid body are connected with a cooling source through the cooling loop to form a complete low-temperature loop; the cooling box is of a hollow structure, the outside of the cooling box is sealed and insulated by heat insulation materials, the inside of the cooling box is provided with a low-temperature pipeline, and the low-temperature pipeline is communicated with a cooling source to keep the temperature in the cooling box low during operation.

Furthermore, the fastening bolt can be used as a telescopic cylinder to provide a plate blank locking force, the telescopic cylinder is arranged on the gantry structure and connected with the pressing plate, and the pressing plate is driven to press the plate blank when the gantry structure works; the gantry structure ensures freedom in both vertical and horizontal (along the welding direction).

Compared with the prior art, the invention has the following advantages:

1. according to the method and the device for preparing the large-width aluminum alloy tailor-welded blank, the newly quenched solid solution blank is cooled to a low temperature through the fixed clamping plate, normal-temperature natural aging is prevented, the preparation of the ultra-wide blank in the solid solution state can be realized, the excellent forming performance of the solid solution state is kept, and the problem that grains grow abnormally after welding and solid solution are carried out is solved.

2. According to the method and the device for preparing the large-width aluminum alloy tailor-welded blank, the ultra-wide blank is prepared by friction stir welding at low temperature, so that welding in a solid solution state can be ensured, the cooling of a welding area can be accelerated, and the problem of weakening of the structure performance of a welding seam is avoided.

3. According to the method and the device for preparing the large-width aluminum alloy tailor-welded blank, the detachable single-rail gantry structure is adopted to fix the friction stir welding machine and compress the welding end part, so that an ultra-large friction stir welding machine is not needed, the large thin-wall part can be conveniently built on the forming site, and the difficulty in transporting the ultra-wide blank is avoided.

In conclusion, the technical scheme of the invention can solve the problem that the prior art can not obtain the large-size ultra-wide aluminum alloy plate blank suitable for the integral forming of the large-size thin-wall part.

For the above reasons, the present invention can be widely applied to the fields of sheet metal forming and the like.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a schematic view of an ultra-wide slab manufacturing apparatus according to embodiment 1 of the present invention.

Fig. 2 is a schematic structural view of a low temperature box base in embodiment 2 of the present invention.

Fig. 3 is a schematic structural view of a base and a cover plate of the low temperature box in embodiment 2 of the present invention.

Fig. 4 is a schematic view of an ultra-wide slab manufacturing apparatus according to embodiment 2 of the present invention.

Fig. 5 is a schematic view of an ultra-wide slab manufacturing apparatus according to embodiment 3 of the present invention.

FIG. 6 is a diagram of a gold phase of a weld joint after solid solution of 2219 aluminum alloy in an annealed state in friction stir welding.

FIG. 7 is a gold phase diagram of a 2219 aluminum alloy solid solution friction stir welding seam of the invention.

In the figure: 1. a heat insulation plate; 2. a solid rigid body; 3. fixing a clamping plate; 3-1, a low-temperature box seat; 3-2, a transfusion pipeline; 3-3, a cover plate; 4. a slab; 5. a gantry structure; 5-1, a telescopic cylinder; 6. a horizontal slider; 7. a vertical slide block; 8. a welding head; 9. pressing a plate; 10. a cooling circuit; 11. a cooling source; 12. a temperature control device.

Detailed Description

It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict. The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments according to the invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

The relative arrangement of the components and steps, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise. Meanwhile, it should be understood that the sizes of the respective portions shown in the drawings are not drawn in an actual proportional relationship for the convenience of description. Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate. In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.

In the description of the present invention, it is to be understood that the orientation or positional relationship indicated by the directional terms such as "front, rear, upper, lower, left, right", "lateral, vertical, horizontal" and "top, bottom", etc., are generally based on the orientation or positional relationship shown in the drawings, and are used for convenience of description and simplicity of description only, and in the absence of any contrary indication, these directional terms are not intended to indicate and imply that the device or element so referred to must have a particular orientation or be constructed and operated in a particular orientation, and therefore should not be considered as limiting the scope of the present invention: the terms "inner and outer" refer to the inner and outer relative to the profile of the respective component itself.

Spatially relative terms, such as "above … …," "above … …," "above … …," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial relationship to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if a device in the figures is turned over, devices described as "above" or "on" other devices or configurations would then be oriented "below" or "under" the other devices or configurations. Thus, the exemplary term "above … …" can include both an orientation of "above … …" and "below … …". The device may be otherwise variously oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

It should be noted that the terms "first", "second", and the like are used to define the components, and are only used for convenience of distinguishing the corresponding components, and the terms have no special meanings unless otherwise stated, and therefore, the scope of the present invention should not be construed as being limited.

As shown in fig. 1 to 7, the invention provides a method for preparing a large-size and wide-width aluminum alloy tailor-welded blank, which is used for preparing a large-size and wide-width aluminum alloy blank by low-temperature friction stir welding, and comprises the following specific steps:

the method comprises the following steps: and determining a slab. Selecting a proper aluminum alloy plate blank 4 according to the width size of the ultra-wide plate;

step two: and (6) cooling. Cooling the fixed clamping plate 3 to-40-0 ℃;

step four: and (5) assembling, fixing and cooling the plate blank. Placing a plurality of solid solution state plate blanks on a fixed clamping plate 3, fixing the plate blanks, butting the parts to be welded of the two plate blanks, pressing the parts close to a welding area through a pressing plate 9, ensuring that the plate blanks do not move relatively in the welding process, and cooling the solid solution state plate blanks to-40-0 ℃ through heat conduction of the fixed clamping plate 3;

step five: and (5) stirring and friction welding. And driving a motor to enable the welding head 8 to rotate at a constant speed, slowly inserting the stirring pin into the plate blank, moving the welding head 8 forwards at a constant speed along the welding direction while rotating, and forming compact metal combination on the original solid solution state plate blank under the combined action of a heat machine and a machine to obtain the ultra-wide plate blank.

In the second step, a liquid conveying pipeline is opened inside the fixed clamping plate 3, and a low-temperature medium is conveyed into the pipeline through the cooling source 11 to cool the fixed clamping plate 3 to a set temperature.

In the second step, the fixed clamping plate 3 is in a box-type combined structure, the solid rigid body 2 is adopted only in the welding zone needing the supporting force, and the cooling box is adopted in other cooling zones. A communicating pipeline is arranged in the solid rigid body 2, the cooling box is of a hollow structure, the outside of the cooling box is sealed and insulated by heat insulation materials, a low-temperature pipeline is arranged in the cooling box, and the pipeline is communicated with the cooling source 11 during operation to keep the temperature in the cooling box low.

In the fourth step, a single-rail gantry structure 5 is adopted to fix the friction stir welding machine and the compression welding end part, the end part of the connected slab is ensured to be in close contact through the limiting of the clamping groove, and the motion trail of the slab contact gap and the welding machine is made to coincide.

In the fourth step, the fastening bolts are replaced by the gantry structure 5 and the telescopic cylinder 5-1 to provide a slab locking force, and the gantry structure 5 needs to ensure the freedom degrees in the vertical direction and the horizontal direction (along the welding direction).

As a preferred embodiment, the aluminium alloy slab is mainly a heat-treatable strengthened aluminium alloy, such as a 2 xxx, 6 xxx, 7 xxx series aluminium alloy sheet.

In the fifth step, the friction stir welding head 8 keeps constant feeding and constant rotating, the feeding speed is 150 mm/min-300 mm/min, and the rotating speed is 600 r/min-1400 r/min.

The invention also provides a novel large-width aluminum alloy tailor-welded blank preparation device which mainly comprises a welding device, a fixing device and a cooling device. Wherein, welding device: including a friction stir welding horn 8 (of suitable size) and a motor for driving the horn 8. The fixing device includes: the single-rail gantry structure 5 for fixing the welding device, the solid rigid body 2 for placing and positioning the plate blank, the pressing plate 9 for fixing the plate blank and the fastening bolts. The cooling device includes: a fixing card 3, a cooling circuit 10, a cooling source 11 and a temperature control device 12.

When in installation, firstly, the gantry structure 5 is fixed on the solid rigid body 2, and the fixed clamping plates 3 for cooling are fixed on two sides of the solid rigid body 2; then the fixed clamping plate 3 and the solid rigid body 2 are connected with a cooling source 11 by using a liquid conveying pipe to form a complete low-temperature loop; then, a horizontal sliding block 6 is arranged in a guide rail of the gantry structure 5, and a vertical sliding block 7 fixed with a welding device is arranged in the guide rail of the horizontal sliding block 6; connecting a temperature control device 12 with a cooling source 11, and fixing a low-temperature thermocouple on a fixed clamping plate 3 to measure the temperature in real time; and finally, connecting the welding device and the temperature control device 12 with a power supply to finish the installation of the large-size ultra-wide aluminum alloy plate blank preparation device.

In the slab preparation process, a cooling source 11 conveys a low-temperature medium to a liquid conveying pipeline of a fixed clamping plate 3 through a cooling loop 10, a low-temperature environment is created by heat conduction, a temperature control device 12 adopts feedback regulation, and the flow rate of the low-temperature medium is controlled according to the real-time temperature of the fixed clamping plate 3 (cooling plate), so that the temperature of the device is stabilized at a set temperature, and the cooling function is realized; the welding head 8 rotates at a constant speed under the drive of the motor, and moves along the welding direction under the drive of the horizontal sliding block 6 and the vertical sliding block 7, so that the welding function is realized; after the plate blank is positioned, pressing force is provided by the pressing plate 9 and is fixed on the solid rigid body 2, so that the positioning function is realized.

Example 1

As shown in FIG. 1, in this example, 2219 aluminum alloy slabs with the size of 5m × 5m × 4.5mm are required to be prepared, and two original slabs 4 used are 2219 aluminum alloy plates in an annealed state, the plane size is 5m × 2.5m, and the wall thickness is 4.5 mm. The cooling source 11 conveys the low-temperature medium to a liquid conveying pipeline of the fixing clamping plate 3 through the cooling circuit 10, and the fixing clamping plate 3 cools the slab 4 through heat conduction. The positioning and support of the welding head 8 is achieved by means of the gantry 5. And the plate blank 4 is tightly pressed by using the pressing plate 9 after being positioned, so that the play in the welding process is prevented. The temperature control device 12 adopts feedback adjustment to control the flow rate of the low-temperature medium according to the real-time temperature of the cooling plate (the fixed clamping plate 3) so as to stabilize the temperature of the device at the set temperature. The bottom of the fixed clamping plate and the bottom of the solid rigid body are connected with a heat insulation plate 1 together.

The first step is as follows: and starting the cooling source 11, filling the low-temperature medium into the fixed clamping plate 3, reducing the temperature of the fixed clamping plate to-40 ℃, and controlling the flow rate of the low-temperature medium by the temperature control device 12 to keep the temperature stable.

The second step is that: the plate blank 4 is rapidly quenched after the solution treatment at 535 ℃ for 1h, and the residual liquid on the surface is wiped dry to obtain the solid solution plate blank 4.

The third step: the solid solution state plate blank 4 is tightly placed on the fixed clamping plate 3, firstly positioned to ensure that the gap between the two plates is superposed with the motion trail of the welding machine, and then fixed by the pressing plate 9. The welding head 8 is arranged on the gantry structure 5 through horizontal and vertical sliders, the horizontal slider 6 can move horizontally (along the welding direction) along a guide rail on the gantry structure 5, and the welding head 8 is fixed on the vertical slider 7 and can move vertically along the guide rail on the horizontal slider 6.

The fourth step: and starting the welding device, feeding the welding head 8 along the welding direction at a speed of 200mm/min and a rotating speed of 1300r/min, and obtaining the ultra-wide plate blank after welding.

The fifth step: the welding head 8 is raised, the press plate 9 is opened and the slab 4 is rapidly taken out to the processing device.

As shown in fig. 6 and 7, the weld gold phase diagram of the prior 2219 aluminum alloy after being subjected to friction stir welding and solution treatment in an annealed state is obviously different from the weld gold phase diagram of a 2219 aluminum alloy solid solution state slab prepared by applying the invention. It can be seen that after the welding in the annealed state, obvious abnormal growth of grains exists in the solid solution process, and the mechanical property of the connecting area can be seriously influenced by the coarse grains; the size of the crystal grain of the plate blank connecting area is basically consistent with that of the parent metal area, and the mechanical property of the plate blank connecting area is similar to that of the parent metal area. Compared with the traditional welding method, the method has the advantages that the abnormal growth of the crystal grain structure of the plate blank connecting area can be effectively prevented, the mechanical property of the connecting area is improved, and the method has important significance for preparing large-size ultra-wide plate blanks.

Example 2

As shown in FIG. 2, FIG. 3 and FIG. 4, in this example, it is required to prepare 2A14 aluminum alloy slabs with the size of 6m × 6m × 8mm, and two original slabs 4 used are 2A14 aluminum alloy plates in an annealed state, with the plane size of 6m × 3m and the wall thickness of 8.0 mm. The cooling method is different from the method for cooling the fixed clamping plate, the fixed clamping plate adopts a low-temperature box type structure and comprises a low-temperature box base 3-1, a liquid conveying pipeline 3-2 and a cover plate 3-3, the liquid conveying pipeline 3-2 is arranged inside the low-temperature box base 3-1 and can be in a U shape, a rectangular groove is formed in the middle of the low-temperature box base 3-1, the plate blank is placed in the rectangular groove, and the cover plate 3-3 covers the top of the low-temperature box base 3-1. The cooling source 11 delivers the low-temperature medium to the liquid delivery pipe 3-2 in the low-temperature box base 3-1 through the cooling circuit 10, so that the temperature in the low-temperature box is reduced, and the slab is further cooled. The positioning and support of the welding head 8 is achieved by means of the gantry 5. The plate blank 4 is positioned and pressed by a pressing plate 9, so that the movement in the welding process is prevented. The temperature control device 12 controls the flow rate of the low-temperature medium according to the real-time temperature in the low-temperature box by adopting feedback regulation, so that the temperature of the low-temperature box is stabilized at the set temperature.

The first step is as follows: the cooling source 11 is started to fill the low-temperature medium into the infusion pipeline 3-2, so that the temperature of the low-temperature medium is reduced to-40 ℃, and the temperature control device 12 controls the flow rate of the low-temperature medium to keep the temperature stable.

The second step is that: the plate blank 4 is subjected to solution treatment at 490 ℃ for 1h, then rapidly quenched, and the surface residual liquid is wiped dry to obtain a solid solution plate blank 4.

The third step: the solid solution state plate blank 4 is tightly placed on a low-temperature box seat 3-1, firstly positioned to enable the gap between the two plates to be superposed with the motion track of a welding machine, and then fixed by a pressing plate 9 and covered by a cover plate 3-3. The welding head is arranged on the gantry structure 5 through horizontal and vertical sliding blocks, the horizontal sliding block 6 can move horizontally (along the welding direction) along a guide rail on the gantry structure 5, and the welding head 8 is fixed on the vertical sliding block 7 and can move vertically along the guide rail on the horizontal sliding block 6.

Example 3

As shown in FIG. 5, in this example, 2195 aluminum alloy slabs with the size of 3m × 3m × 3.0mm are required to be prepared, and the two original slabs 4 used are annealed 2195 aluminum alloy plates with the plane size of 3m × 1.5m and the wall thickness of 3.0 mm. The cooling source 11 conveys the low-temperature medium to a liquid conveying pipeline of the fixing clamping plate 3 through the cooling circuit 10, and the fixing clamping plate 3 cools the slab 4 through heat conduction. The positioning and support of the welding head 8 is achieved by means of the gantry 5. After the slab 4 is positioned, the pressing plate 9 is driven to be pressed tightly through a plurality of telescopic cylinders 5-1 arranged on the gantry structure 5, so that the phenomenon of movement in the welding process is prevented. The temperature control device 12 adopts feedback adjustment to control the flow rate of the low-temperature medium according to the real-time temperature of the fixed clamping plate 3 (cooling plate), so that the temperature of the device is stabilized at the set temperature.

The second step is that: the plate blank 4 is rapidly quenched after the solution treatment at 520 ℃ for 1h, and the residual liquid on the surface is wiped dry to obtain the solid solution plate blank 4.

The third step: the solid solution state plate blank 4 is tightly placed on the fixed clamping plate 3, firstly positioned to ensure that the gap between the two plates is superposed with the motion trail of the welding machine, and then fixed by the pressing plate 9. The welding head is arranged on the gantry structure 5 through horizontal and vertical sliding blocks, the horizontal sliding block 6 can move horizontally (along the welding direction) along a guide rail on the gantry structure 5, and the welding head 8 is fixed on the vertical sliding block 7 and can move vertically along the guide rail on the horizontal sliding block 6.

The fourth step: and starting the welding device, feeding the welding head 8 along the welding direction at a speed of 200mm/min and a rotating speed of 1200r/min, and obtaining the ultra-wide plate blank after welding.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. The preparation method of the large-width aluminum alloy tailor-welded blank is characterized by comprising the following steps of:

the method comprises the following steps: determining a slab: selecting a proper aluminum alloy plate blank according to the width size of the ultra-wide plate;

step two: cooling treatment: cooling the fixed clamping plate to-40-0 ℃;

step three: plate blank solution treatment: simultaneously carrying out solution treatment on a plurality of aluminum alloy plate blanks to obtain solid solution plate blanks;

step four: assembling, fixing and cooling a plate blank: placing a plurality of solid solution state plate blanks on a fixing clamping plate, fixing the plate blanks, butting the parts to be welded of the two plate blanks, pressing the parts close to a welding area through a pressing plate, ensuring that the plate blanks do not move relatively in the welding process, and cooling the solid solution state plate blanks to-40-0 ℃ through heat conduction of the fixing clamping plate;

step five: friction stir welding: and driving a motor to enable a welding head of the friction stir welding to rotate at a constant speed, slowly inserting a stirring pin of the welding head into the plate blank, moving the welding head forwards at a constant speed along the welding direction while rotating, and forming compact metal combination on the original solid solution state plate blank under the combined action of a heat machine to obtain the ultra-wide plate blank.

2. A large-width aluminum alloy tailor welded blank manufacturing method according to claim 1, wherein said aluminum alloy blank is a heat-treatable strengthened aluminum alloy, being a 2 xxx, 6 xxx or 7 xxx series aluminum alloy sheet.

3. The method for preparing the large-width aluminum alloy tailor-welded blank according to claim 1, wherein in the fifth step, the friction stir welding head keeps constant feeding and constant rotating, the feeding speed is 100 mm/min-300 mm/min, and the rotating speed is 600 r/min-1400 r/min.

4. An apparatus for manufacturing a tailor welded blank made of a large-width aluminum alloy according to any one of claims 1 to 3, comprising: fixing device, installation welding set and cooling device on fixing device, fixing device is used for realizing the fixed of slab, is provided with moving mechanism on it, welding set installs on moving mechanism, moving mechanism is used for realizing welding set along the motion of welding direction, welding set is used for welding the position of treating welding between the slab, cooling device links to each other with fixing device for provide the low temperature environment, cool down to the slab.

5. The large-width aluminum alloy tailor welded blank manufacturing device according to claim 4, wherein said welding device is a friction stir welding machine, comprising: the welding head of the friction stir welding and the motor are arranged on the moving mechanism and used for driving the welding head to weld the parts to be welded between the plate blanks.

6. The large-width aluminum alloy tailor welded blank manufacturing apparatus according to claim 4, wherein said fixing means further comprises: the single-rail gantry structure is used for installing a moving mechanism, the solid rigid body is used for placing and positioning the plate blank, and the pressing plate and the fastening bolt are used for fixing the plate blank; the gantry structure is fixed on the solid rigid body, the two plate blanks are placed on the top of the solid rigid body together, the part to be welded between the plate blanks is positioned on the solid rigid body and is pressed tightly by a pressing plate close to the part to be welded, and the pressing plate is fixed by a connected fastening bolt;

the moving mechanism comprises a horizontal sliding block and a vertical sliding block, the horizontal sliding block is arranged in a guide rail of the gantry structure, the vertical sliding block is arranged in the guide rail of the horizontal sliding block, and the welding device is fixed on the vertical sliding block;

the friction stir welding machine is fixed by adopting a single-rail gantry structure, the welding end part is compressed, the end part of a connecting plate blank is ensured to be in close contact through the limiting of a clamping groove, and the contact gap of the plate blank is superposed with the movement track of the welding machine.

7. The large-width aluminum alloy tailor welded blank manufacturing apparatus according to claim 4, wherein said cooling device comprises: the cooling device comprises a fixed clamping plate, a cooling loop, a cooling source and a temperature control device, wherein two fixed clamping plates are respectively and fixedly connected to two sides of a solid rigid body of the fixing device and used for cooling the plate blank; the cooling source is connected with the fixed clamping plate through a cooling loop and creates a low-temperature environment by means of heat conduction; the temperature control device is connected with the cooling source and used for stabilizing the temperature of the device at a set temperature.

8. The large-width aluminum alloy tailor-welded blank manufacturing device according to claim 7, wherein a liquid delivery pipe communicated with a cooling circuit is opened inside the fixing clamp plate, a cooling source delivers low-temperature medium into the liquid delivery pipe through the cooling circuit to cool the fixing clamp plate to a set temperature, and the fixing clamp plate creates a low-temperature environment for the blank by means of heat conduction;

the temperature control device adopts feedback adjustment, and a low-temperature thermocouple is fixed on the fixed clamping plate and used for measuring the temperature of the fixed clamping plate in real time; the flow velocity of the low-temperature medium is controlled according to the real-time temperature of the fixing clamping plate, so that the temperature of the device is stabilized at a set temperature, and the cooling function is realized.

9. The large-width aluminum alloy tailor-welded blank manufacturing apparatus according to claim 8, wherein said fixing clip board and said solid rigid body are of a box-type combined structure, the solid rigid body is used only in a welding zone requiring a supporting force, and the other cooling zones are cooling boxes; a communication pipeline communicated with the cooling loop is arranged in the solid rigid body, and the fixed clamping plate and the solid rigid body are connected with a cooling source through the cooling loop to form a complete low-temperature loop; the cooling box is of a hollow structure, the outside of the cooling box is sealed and insulated by heat insulation materials, the inside of the cooling box is provided with a low-temperature pipeline, and the low-temperature pipeline is communicated with a cooling source to keep the temperature in the cooling box low during operation.

10. The large-width aluminum alloy tailor-welded blank manufacturing device according to claim 6, wherein said fastening bolts can be replaced by a telescopic cylinder to provide a blank locking force, said telescopic cylinder is installed on the gantry structure and connected with the pressing plate, and drives the pressing plate to press the blank when working; the gantry structure ensures the freedom degrees in vertical and horizontal directions.