Friction stir progressive deposition forming device and method for dissimilar metal special-shaped transition joint

Abstract

The invention discloses a friction stir progressive deposition forming device and method for a heterogeneous metal special-shaped transition joint, and relates to a deposition forming device and method. The invention aims to solve the problems that the joint performance is deteriorated due to intermetallic compounds at the interface of a heterogeneous metal special-shaped transition joint, especially an aluminum-steel transition joint, and the formation of the joint is hindered by oxides in aluminum steel. The device comprises a rotating part, a movable material storage part, a lifting control mechanism and a fixed connecting mechanism. The rotating component is installed at the upper end of the movable material storage component, the fixed connecting mechanism is installed at the lower end of the movable material storage component, and the lifting control mechanism is connected with the movable material storage component. The invention belongs to the technical field of metal material connection.

Description

Technical Field

[0001] The invention relates to a deposition forming device and method, belonging to the technical field of metal material connection. Background Art

[0002] In the fields of automobiles, ships, aerospace, industrial manufacturing, etc., due to the special requirements for mechanical, corrosion resistance and weight control of materials, the material selection requirements are high. Dissimilar composite structural materials such as aluminum steel are gradually replacing single metal materials for production and manufacturing due to their lightweight and excellent mechanical properties. However, due to the huge difference in physical properties between steel and aluminum alloys and the generation of intermetallic compounds during the connection process, this has a great restriction and impact on the size, shape and mechanical properties of the joint.

[0003] Friction stir additive manufacturing technology does not involve the melting and solidification of materials, which effectively avoids the generation of defects such as pores and cracks in heterogeneous metal special-shaped transition joints, but is limited in the manufacture of heterogeneous metal special-shaped transition joints with diverse shapes. Incremental forming technology does not require special molds. It achieves the final forming effect by gradually promoting plastic deformation of small areas, and can manufacture heterogeneous metal special-shaped transition joints with various shapes, but it is usually formed on existing plates, and the degree of freedom is limited. Therefore, the present invention combines friction stir additive manufacturing technology and incremental forming technology, and innovatively proposes friction stir incremental deposition forming technology, which can manufacture heterogeneous metal special-shaped transition joints with diverse shapes and excellent performance.

[0004] In the forming process of friction stir progressive forming technology, the stirring head will break the oxide film in the metal on both sides of the joint by rotating and extruding and bumping, and at the same time, the dislocation and other channels generated by the strong plastic deformation of the material are used to drive the rapid diffusion of atoms to form. At the same time, due to the fast atomic diffusion rate, low forming peak temperature and short high temperature residence time in friction stir progressive forming, the thickness of the intermetallic compound can be effectively controlled to improve the comprehensive performance of the joint, but the rapid atomic diffusion caused by the stirring head will increase the thickness of the intermetallic compound. By controlling the forming process parameters, the thickness of the intermetallic compound can be obtained to improve the quality of the joint. Further, taking the manufacturing of aluminum-steel transition joints as an example, when friction stir welding is used to weld aluminum-steel joints, due to the different melting points of the two, only steel plates of limited thickness can be welded, and welding of steel plates with a wide thickness range cannot be achieved. The friction stir progressive deposition forming technology can heat-plasticize the aluminum alloy wire through continuous feeding of aluminum alloy wire and the breaking, stacking and stirring of the wire by the joint manufacturing mechanism, and then deposit it on the surface of the steel plate, so as to achieve the welding of aluminum alloy on the surface of the steel plate with adjustable thickness. Friction stir progressive deposition forming technology can control the deposition direction and sequence of thermoplastic aluminum alloy as well as the position and order of progressive forming, thereby being able to produce aluminum-steel transition joints of various shapes.

[0005] Therefore, the heterogeneous metal special-shaped transition joint manufacturing device invented based on the stir friction progressive deposition forming technology proposed in the present invention can manufacture heterogeneous metal special-shaped transition joints with excellent mechanical properties and personalized shape and structure, meeting the urgent needs of the automotive, shipbuilding, aerospace, industrial manufacturing and other fields. Summary of the invention

[0006] The present invention aims to solve the problems of deterioration of joint performance caused by intermetallic compounds at the interface of heterogeneous metal shaped transition joints, especially aluminum-steel transition joints, and the problem that oxides in aluminum and steel hinder joint forming, and further proposes a friction stir progressive deposition forming device and method for heterogeneous metal shaped transition joints.

[0007] The technical solution adopted by the present invention to solve the above problems is: the device of the present invention comprises a rotating component, a movable material storage component, a lifting control mechanism and a fixed connection mechanism;

[0008] The rotating component is installed on the upper end of the movable material storage component, the fixed connection mechanism is installed on the lower end of the movable material storage component, and the lifting control mechanism is connected to the movable material storage component.

[0009] Further, the rotating component includes a clamping connection portion, a transition portion, a threaded portion and a stirring head;

[0010] The clamping connection part, the transition part, the threaded part and the stirring head are fixedly connected in sequence from top to bottom into one body.

[0011] Further, the movable material storage component includes a transmission portion, a transition portion, a first rotation limiting portion, a feeding portion and a round bottom shaft shoulder portion;

[0012] The transmission part, the transition part and the feeding part are fixedly connected in sequence from top to bottom into one body, the lower end of the feeding part is provided with a round bottom shaft shoulder part, and the side wall of the feeding part is provided with a first rotation limiting part.

[0013] Further, the lifting control mechanism includes a motor, a speed reducer, a small pulley, a belt, a large pulley, a large pulley fixing component and a fixing frame;

[0014] The reducer is installed at one end of the fixed frame, the motor shaft of the motor is connected to the reducer, the large pulley fixing component is installed at the other end of the fixed frame, the large pulley is installed on the large pulley fixing component, the small pulley is installed on the reducer, and the small pulley is connected to the large pulley through a belt.

[0015] Further, the fixed connection mechanism includes a fixed portion and a second rotation limiting portion;

[0016] The upper end of the fixing portion is fixedly connected with the upper end of the second rotation limiting portion to form a whole.

[0017] The steps of the method of the present invention include:

[0018] Steps: adjust the position of the movable material storage component according to the forming requirements, start the machine to rotate the main shaft to drive the rotating component to start rotating, the device gradually approaches the steel surface according to the program, and stays for a predetermined time after the stirring head rotates and penetrates into the steel plate, and then immediately starts the wire feeder, and the aluminum alloy wire enters the cavity between the movable material storage component and the rotating component through the feeding hole, and is broken into small metal segments under the rotary shearing action of the threaded part of the rotating component, and then transported downward along the threaded rod under the action of gravity;

[0019] Step 1: The crushed small aluminum alloy segments are continuously accumulated in the cavity between the movable material storage component and the rotating component, and are further deformed and then thermoplasticized under the rotation and extrusion of the threaded part. The thermoplasticized aluminum alloy is deposited and formed under the forging and impact of the circular bottom shoulder of the movable material storage component and the cooling of the external airflow. The high-speed rotation and extrusion of the stirring head of the rotating component will break the oxide film in the aluminum steel and create fast channels such as dislocations to accelerate the flow and diffusion of the thermoplastic aluminum alloy and achieve reliable interlayer bonding. At the same time, the stirring head will perform point-by-point collision and progressive forming on the newly deposited aluminum alloy to obtain a joint of the desired shape.

[0020] Step 1: During the forming process, the height of the movable material storage component is adjusted as needed to adjust the thickness of the thermoplastic aluminum alloy accumulated between the round bottom shaft shoulder and the sample surface, so as to achieve the purpose of accelerating the forming speed.

[0021] The beneficial effects of the present invention are:

[0022] 1. The present invention uses a device for forming heterogeneous metal special-shaped transition joints by friction stir progressive deposition to break through the aluminum-steel transition joint manufacturing mode in which friction stir welding can only weld aluminum on steel plates with limited thickness, and realizes a joint manufacturing mode in which aluminum is deposited on steel plates with adjustable thickness, thus broadening the shape and function of the joint;

[0023] 2. The present invention realizes the adjustment of the height of the lifting control mechanism through the cooperation between the lifting control mechanism transmission part and the lifting control mechanism large pulley, that is, the adjustment of the thickness of the thermoplastic aluminum alloy accumulated between the round bottom shaft shoulder and the pattern surface, which can increase the joint forming rate and improve the production efficiency;

[0024] 3. The present invention uses a friction stir progressive deposition forming device for heterogeneous metal special-shaped transition joints, so that the stirring head can break the aluminum alloy oxide film, create dislocations and other fast channels to drive the rapid diffusion of atoms, thereby improving the joint forming rate and the comprehensive performance of the joint, showing the characteristics of fast and good. During the forming process, the progressive impact of the stirring head can manufacture joints of various shapes without destroying the joint performance, greatly improving its application scenarios and meeting personalized needs;

[0025] 4. The present invention realizes the process from solid state to thermoplastic state through crushing, extrusion and transportation by aluminum alloy wire feeding. No liquid phase is formed in the whole forming process, which effectively avoids the generation of defects such as pores and cracks in the aluminum-steel transition joint, and ensures that the manufactured joint has good comprehensive performance. Since the wire feeding process can be carried out continuously, the present invention is suitable for the preparation of large and complex structures. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the overall structure of the friction stir progressive deposition forming device for heterogeneous metal special-shaped transition joints according to the present invention;

[0027] Figure 2 It is a schematic diagram of the rotating parts of the joint manufacturing mechanism of the present invention;

[0028] Figure 3 It is a schematic diagram of a movable material storage component of a joint manufacturing mechanism according to the present invention;

[0029] Figure 4 is a side view of the lifting control mechanism of the present invention;

[0030] Figure 5 is a front cross-sectional view of the lifting control mechanism of the present invention;

[0031] Figure 6 is a schematic diagram of the fixed connection mechanism of the present invention;

[0032] Figure 7 It is a schematic diagram of the lower limit of movement of the movable material storage component described in this invention;

[0033] Figure 8 It is a schematic diagram of the upper limit of movement of the movable material storage component of the present invention;

[0034] 1-rotating component, 101-clamping connection part, 10101-side milling plane, 102-transition part, 10201-positioning surface, 103-threaded part, 10301-threaded rod, 104-stirring head;

[0035] 2- movable material storage component, 20- transmission part, 20101- external thread, 202- transition part, 203- rotation limiting part, 204- feeding part, 20401- feeding hole, 205- round bottom shaft shoulder;

[0036] 3-lifting control mechanism, 301-motor, 302-reducer, 303-small pulley, 304-belt, 305-large pulley, 306-large pulley fixing component, 30601-rivet, 30602-expansion sleeve, 30603-connecting circular plate, 307-fixing frame, 30701-positioning hole;

[0037] 4-fixed connection mechanism, 401-fixed part, 40101-positioning hole, 40102-positioning surface, 402-rotation limiting part, 40201-inclined trapezoidal column, 40202-slot, 40203-positioning surface. DETAILED DESCRIPTION

[0038] Specific implementation method 1: Figure 1 As shown, a friction stir progressive deposition forming device for heterogeneous metal special-shaped transition joints comprises a rotating component 1, a movable material storage component 2, a lifting control mechanism 3 and a fixed connection mechanism 4;

[0039] The rotating part 1 is installed on the upper end of the movable material storage part 2 , the fixed connection mechanism 4 is installed on the lower end of the movable material storage part 2 , and the lifting control mechanism 3 is connected to the movable material storage part 2 .

[0040] Among them, the rotating part 1, the movable storage part 2, the fixed connection mechanism 4 and the large pulley 305 in the lifting control mechanism 3 are coaxially installed and cooperate with each other; before starting the forming, the movable storage part 2 is placed in the middle section of the movable interval so that it can be adjusted up and down during the forming process to achieve the adjustment of the thickness of the thermoplastic aluminum alloy accumulated between the round bottom shaft shoulder 205 and the pattern surface to meet different forming requirements.

[0041] Specific implementation method 2: Figure 2 As shown, the rotating component 1 includes a clamping connection portion 101, a transition portion 102, a threaded portion 103 and a stirring head 104;

[0042] The clamping connection portion 101, the transition portion 102, the threaded portion 103 and the stirring head 104 are fixedly connected in sequence from top to bottom into one body.

[0043] The transmission part 201 is used to cooperate with the large pulley 305 in the lifting control mechanism 3 to realize the up and down movement of the movable material storage part 2;

[0044] The transition part is located between the transmission part 201 and the feeding part 204 and plays a transitional connection role;

[0045] The limiting rotation part 203 is used to prevent the movable material storage part 2 from rotating and causing uncontrollable up and down movement of the movable material storage part 2. It has three symmetrically distributed rectangular grooves. The grooves cooperate with the fixed connection mechanism 4 to limit the rotation of the movable material storage part 2, while ensuring that the up and down movement of the movable material storage part 2 is not affected. The feeding part 204 is located in the lower half of the movable material storage part 2. The aluminum alloy wire used for stirring friction progressive deposition is fed into the internal cavity of the movable material storage part 2 from the feeding hole 20401 on the side of the feeding part, and The threaded portion 103 of the rotating component 1 is sheared into fine particles upon contact and then transported and deposited on the surface of the base material. The feeding hole 20401 obliquely penetrates the side wall of the movable storage component 2 downward. The position of the internal hole ensures that it is always located between two adjacent threaded rods 10301 of the threaded portion 103 of the rotating component 1 when the movable storage component 2 moves up and down, thereby achieving smooth crushing and transportation of the wire during the movement of the movable storage component 2; the round bottom shaft shoulder 205 below the feeding portion is used to compact and smooth the thermoplasticized aluminum alloy in the stirring head 104 of the rotating component 1. The rotating component 1 is composed of a clamping connection part 101, a transition part 102, a threaded part 103 and a stirring head 104; the clamping connection part 101 is used to connect with the rotating spindle rotor part of the machining equipment, and is provided with two side milling planes 10101 for side clamping; the transition part 102 is used to connect the clamping connection part 101 and the threaded part 103 and realize the matching positioning with the movable material storage part 2; the threaded part 103 is provided with a convex rectangular threaded rod 10301, which is used to move the material from the feeding hole 20 The aluminum alloy wire fed by 401 is conveyed and extruded toward the stirring head 104, and in the process the aluminum alloy wire is broken and thermoplasticized, and then densely formed under the stirring plastic deformation action of the stirring head 104; the stirring head 104 is located at the bottom of the rotating part 1, is hemispherical and has a distance from the bottom end of the threaded part 103, and this distance is the adjustment range of the movable storage part 2; compared with the truncated cone stirring head, the hemispherical stirring head 104 has a smaller shearing effect when stirring the material, which is suitable for the requirements of progressive forming.

[0046] Specific implementation method three: Figure 3 As shown, the movable material storage component 2 includes a transmission portion 201, a transition portion 202, a first rotation limiting portion 203, a feeding portion 204 and a round bottom shaft shoulder portion 205;

[0047] The transmission part 201 , the transition part 202 , and the feeding part 204 are fixedly connected in sequence from top to bottom into one body. A round bottom shoulder part 205 is provided at the lower end of the feeding part 204 , and a first rotation limiting part 203 is provided on the side wall of the feeding part 204 .

[0048] Specific implementation method four: Figure 4 and Figure 5As shown, the lifting control mechanism 3 includes a motor 301, a reducer 302, a small pulley 303, a belt 304, a large pulley 305, a large pulley fixing component 306 and a fixing frame 307;

[0049] The reducer 302 is installed at one end of the fixed frame 307, the motor shaft of the motor 301 is connected to the reducer 302, the large pulley fixing component 306 is installed at the other end of the fixed frame 307, the large pulley 305 is installed on the large pulley fixing component 306, the small pulley 303 is installed on the reducer 302, and the small pulley 303 is connected to the large pulley 305 through a belt 304.

[0050] The gear ratio of the large pulley 305 to the small pulley 303 is 1:1 to 50:1, which can realize transmission;

[0051] The internal thread of the large pulley 305 cooperates with the transmission part 201 of the movable material storage part 2 to realize the up and down movement of the movable material storage part 2; the large pulley fixing part 306 is composed of a plurality of rivets 30601, a tightening sleeve 30602 and a connecting circular plate 30603, and the connecting circular plate 30603 is connected to the rivet 30601 and the machining equipment. As the rivet 30601 is driven in, the connecting circular plate 30603 squeezes the tightening sleeve 30602 into the inner wall of the large pulley 305 to realize the fixing of the large pulley 305;

[0052] The fixed frame 307 has a plurality of positioning holes 30701 for connecting with the reducer 302 and the machining equipment, and the positioning holes 302 connected with the machining equipment and the positioning holes 40101 in the fixing part 401 of the fixed connection mechanism 4 for fixing with the machining equipment are concentric and have the same diameter, and the fixed frame 307 is used to fix the lifting control mechanism 3 as a whole;

[0053] The belt 304 passes through the outer wall groove of the machining equipment to realize the installation of the lifting control mechanism 3. The lifting control mechanism 3 can ensure that the large pulley 305 drives the movable storage component 2 so that it can be height-adjusted at any time during the joint forming, and can also ensure the strength and bearing capacity of the entire device through the cooperation between the transmission part 201 of the movable storage component 2 and the large pulley 305.

[0054] Specific implementation method five: Figure 6 As shown, the fixed connection mechanism 4 includes a fixed portion 401 and a second rotation limiting portion 402;

[0055] The upper end of the fixing portion 401 is fixedly connected to the upper end of the second rotation limiting portion 402 as a whole.

[0056] The fixing part 401 is used to connect with the non-rotating part of the main shaft of the processing equipment, and has a plurality of positioning holes 40101 evenly distributed around the circumference, which is used to fix with the machining equipment;

[0057] The rotation limiting part 402 is located in the inner cavity of the lower half of the fixed connection mechanism, and has three symmetrically distributed inclined trapezoidal columns 40201, which cooperate with the grooves of the rotation limiting part 203 of the movable material storage part 2 to limit the rotation of the movable material storage part 2 without affecting the upward and downward movement of the movable material storage part 2;

[0058] The side wall of the rotation limiting part 402 of the fixed connection mechanism 4 is provided with a slot 40202, the width of which is equal to the diameter of the feeding hole 20401, and the length design can ensure that the wire can smoothly enter the feeding hole 20401 when the movable storage part 2 moves up and down.

[0059] Specific implementation method six: Figures 1 to 8 As shown, a method for forming a heterogeneous metal special-shaped transition joint by friction stir progressive deposition, the specific steps include:

[0060] Step 1, adjust the position of the movable material storage component 2 according to the forming requirements, start the machine to let the main shaft rotate to drive the rotating component 1 to start rotating, the device gradually approaches the steel surface according to the program, and stays for a predetermined time after the stirring head 104 rotates and penetrates into the steel plate, and then immediately starts the wire feeder, and the aluminum alloy wire enters the cavity between the movable material storage component and the rotating component 1 through the feeding hole 20401, and is broken into small metal segments under the rotation shearing action of the threaded part 103 of the rotating component 1, and then transported downward along the threaded rod 10301 under the action of gravity;

[0061] Step 2: The crushed small aluminum alloy segments are continuously accumulated in the cavity between the movable material storage component 2 and the rotating component 1, and are further deformed and then thermoplasticized under the rotation and extrusion of the threaded portion 103. The thermoplasticized aluminum alloy is deposited and formed under the forging and impact of the round bottom shoulder 205 of the movable material storage component 2 and the cooling effect of the external airflow. The high-speed rotation and extrusion of the stirring head 104 of the rotating component 1 will break the oxide film in the aluminum steel and create fast channels such as dislocations to accelerate the flow and diffusion of the thermoplastic aluminum alloy, and realize reliable interlayer bonding. At the same time, the stirring head 104 performs point-by-point collision and progressive forming on the newly deposited aluminum alloy to obtain a joint of the desired shape.

[0062] Step 3: During the forming process, the height of the movable material storage component 2 is adjusted as needed to adjust the thickness of the thermoplastic aluminum alloy accumulated between the round bottom shaft shoulder 205 and the surface of the pattern, so as to accelerate the forming speed.

[0063] The angle of the machine tool spindle remains unchanged during the forming process, the orientation of the fixed components of the forming device does not change, and the diameter of the feeding hole 20401 of the feeding part 204 is 1 to 5 mm, which can meet the wire feeding process of aluminum alloy wires of different sizes;

[0064] The movable material storage component 2, the rotating component 1, the fixed connection mechanism 4 and the large pulley 305 are coaxially installed, and the circular bottom shoulder portion 205 of the movable material storage component 2 is flush with the bottom end of the threaded portion 103 of the rotating component 1 when it moves to the top within the moving range, and is flush with the circular end surface above the stirring head 104 when it moves to the bottom;

[0065] The threaded portion 103 of the rotating component 1 is not limited to a protruding screw structure, but can also be a screw groove structure. The material selected for manufacturing the joint manufacturing mechanism 1, 2 and the fixed connection mechanism 4 is steel, and the material of the stirring head 104 can be WC-Co to ensure its high strength;

[0066] The shape of the stirring head 104 is not limited to a symmetrical hemispherical shape, and can also be designed as an eccentric hemispherical stirring head 104 to make it stir the material more fully. Stirring heads 104 of different heights can be selected according to the set progressive deposition forming thickness, generally 1 to 3 mm.

[0067] Among them, the potential rotation reason of the movable material storage component 2 is that the thermoplastic aluminum alloy accumulates between the movable material storage component 2 and the rotating component 1, and adheres between the two after solidification, causing a slight disturbance of the movable material storage component 2 when the rotating component 1 rotates, resulting in the possibility of rotation of the movable material storage component 2;

[0068] Compared with the flat-bottomed shoulder, the round-bottomed shoulder can be formed on a curved surface, and its application scenarios are more complex and diverse. Since the transmission part 201 can realize the up and down movement of the movable material storage part 2, its function is to adjust the distance between the round-bottomed shoulder part 205 and the surface of the formed plate, so that the thickness of the thermoplastic aluminum alloy accumulated between the two can be adjusted each time, thereby regulating the speed of the forming process and improving the efficiency of joint manufacturing.

[0069] Among them, on the one hand, the stirring head 104 can accelerate the flow of aluminum alloy by stirring the thermoplastic aluminum alloy, making the atomic distribution at the joint more uniform, and can also break the oxide film in aluminum and steel and create fast atomic diffusion channels such as dislocations, accelerate the forming process, and achieve excellent bonding between aluminum and steel; on the other hand, the stirring head 104 can realize the manufacture of joints of different shapes by gradually extruding and colliding the thermoplastic joint point by point; in addition, if a reinforcing phase (such as aluminum-silicon alloy) is added to the steel in advance, the stirring head can achieve uniform dispersion distribution of the reinforcing phase in the aluminum-steel matrix through stirring, thereby improving the mechanical properties of the joint.

[0070] Among them, after the axial load-bearing capacity test, the design outer diameter of the trapezoidal screw of the movable material storage component 2 transmission part 201 is 42.6mm, the inner diameter is 42.5mm, the inner hollow part cylinder diameter is 36mm, and when the whole is made of steel, the cross-sectional area of ​​the hollow screw is A=257.9mm 2 For steel materials, the yield strength σ is assumed to be y =300MPa, allowable normal stress [σ] = σy , take the safety factor n = 2, then [σ] = 150MPa, according to σ = F / A ≤ [σ], we can get F ≤ [σ] × A, F ≤ 150 × 257.9 = 38685N, it can be seen that it can withstand at least one ton of force. After the contact strength calculation between the nut and the screw, the designed thread diameter D = 44mm, the number of thread turns z = 10, the nut height H = 30mm, according to p = F / πDzH ≤ [p], assuming the allowable pressure [p] = 100MPa, F ≤ [p] × πDzH ≤ 100 × π × 44 × 10 × 30 = 41144930N, it can be seen that its energy strength is very high. It can meet the use requirements. The outer wall of the movable storage component 2 can be opened with an inclined groove to allow the excessive accumulation of aluminum alloy to overflow, to prevent the excessive accumulation of aluminum alloy between the movable storage component 2 and the rotating component 1 from causing blockage and affecting normal wire feeding.

[0071] The above is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technician familiar with this profession can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent replacement and improvement made to the above embodiments without departing from the content of the technical solution of the present invention, based on the technical essence of the present invention, within the spirit and principles of the present invention, still fall within the protection scope of the technical solution of the present invention.

Claims

1. A device for forming heterogeneous metal special-shaped transition joints by friction stirring progressive deposition, characterized in that: It comprises a rotating part (1), a movable material storage part (2), a lifting control mechanism (3) and a fixed connection mechanism (4); The rotating component (1) is installed at the upper end of the movable material storage component (2), the fixed connection mechanism (4) is installed at the lower end of the movable material storage component (2), and the lifting control mechanism (3) is connected to the movable material storage component (2).

2. The device for forming heterogeneous metal special-shaped transition joints by friction stir progressive deposition according to claim 1, characterized in that: The rotating component (1) comprises a clamping connection portion (101), a transition portion (102), a threaded portion (103) and a stirring head (104); The clamping connection portion (101), the transition portion (102), the threaded portion (103) and the stirring head (104) are fixedly connected in sequence from top to bottom into one body.

3. The device for forming heterogeneous metal special-shaped transition joints by friction stir progressive deposition according to claim 1, characterized in that: The movable material storage component (2) comprises a transmission part (201), a transition part (202), a first rotation limiting part (203), a material feeding part (204) and a round bottom shaft shoulder part (205); The transmission part (201), the transition part (202) and the feeding part (204) are fixedly connected in sequence from top to bottom into one body, the lower end of the feeding part (204) is provided with a round bottom shaft shoulder (205), and the side wall of the feeding part (204) is provided with a first rotation limiting part (203).

4. The device for forming heterogeneous metal special-shaped transition joints by friction stir progressive deposition according to claim 1, characterized in that: The lifting control mechanism (3) comprises a motor (301), a reducer (302), a small pulley (303), a belt (304), a large pulley (305), a large pulley fixing component (306) and a fixing frame (307); The reducer (302) is installed on one end of the fixed frame (307), the motor shaft of the motor (301) is connected to the reducer (302), the large pulley fixing component (306) is installed on the other end of the fixed frame (307), the large pulley (305) is installed on the large pulley fixing component (306), the small pulley (303) is installed on the reducer (302), and the small pulley (303) is connected to the large pulley (305) through a belt (304).

5. The device for forming heterogeneous metal special-shaped transition joints by friction stir progressive deposition according to claim 1, characterized in that: The fixed connection mechanism (4) comprises a fixed portion (401) and a second rotation limiting portion (402); The upper end of the fixing portion (401) is fixedly connected to the upper end of the second rotation limiting portion (402) to form a whole.

6. A method for forming a heterogeneous metal special-shaped transition joint by friction stir progressive deposition, characterized in that: The specific steps include: Step 1: adjust the position of the movable material storage component (2) according to the forming requirements, start the machine to rotate the main shaft to drive the rotating component (1) to start rotating, and the device gradually approaches the steel surface according to the program. After the stirring head (104) rotates and penetrates into the steel plate, it stays for a predetermined time, and then immediately starts the wire feeder. The aluminum alloy wire enters the cavity between the movable material storage component and the rotating component (1) through the feeding hole (20401), and is broken into small metal segments under the rotation shearing action of the threaded part (103) of the rotating component (1), and then is transported downward along the threaded rod (10301) under the action of gravity; Step 2: The crushed small aluminum alloy segments are continuously accumulated in the cavity between the movable material storage component (2) and the rotating component (1), and are further deformed and then thermoplasticized under the rotation and extrusion of the threaded part (103). The thermoplasticized aluminum alloy is deposited and formed under the forging, impact and external airflow cooling of the round bottom shoulder (205) of the movable material storage component (2). The high-speed rotation and extrusion of the stirring head (104) of the rotating component (1) will break the oxide film in the aluminum steel and create fast channels such as dislocations to accelerate the flow and diffusion of the thermoplastic aluminum alloy, thereby achieving reliable interlayer bonding. At the same time, the stirring head (104) performs point-by-point collision and progressive forming on the newly deposited aluminum alloy to obtain a joint of the desired shape. Step 3: During the forming process, the height of the movable material storage component (2) is adjusted as needed to adjust the thickness of the thermoplastic aluminum alloy accumulated between the round bottom shaft shoulder (205) and the surface of the pattern, thereby achieving the purpose of accelerating the forming speed.

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