Friction stir additive manufacturing apparatus suitable for aluminum alloy powder

Abstract

A friction stir additive manufacturing apparatus suitable for aluminum alloy powder, the friction stir additive manufacturing apparatus comprising a bed, a bed straight guide rail, columns, a cross beam, a worktable, a cross-beam straight guide rail, a cross-beam straight guide rail hanging plate, a vertical guide rail, a vertical-guide-rail hanging plate, an arc-shaped mounting fixing bracket and a friction stir additive structural component, wherein the bed straight guide rail is fixed to the bed; the worktable is mounted on the bed and can move in an X direction along the bed straight guide rail; the columns are mounted on two sides of the bed and are connected to each other by means of the cross beam; the cross-beam straight guide rail is mounted on the cross beam; the cross-beam straight guide rail hanging plate is mounted on the cross-beam straight guide rail and can move in a Y direction along the cross-beam straight guide rail; the vertical guide rail is mounted on the cross-beam straight guide rail hanging plate; the vertical-guide-rail hanging plate is mounted on the vertical guide rail and can move in a Z direction along the vertical guide rail; and one end of the arc-shaped mounting fixing bracket is fixed to the vertical-guide-rail hanging plate, and the other end of the arc-shaped mounting fixing bracket is fixedly connected to the friction stir additive structural component. The apparatus is simple to manufacture, and convenient to maintain, thereby being easy to promote and apply.

Description

The present invention relates to an additive manufacturing technology, particularly to a friction stir additive manufacturing technology, and specifically to friction stir additive manufacturing equipment suitable for aluminum alloy materials. BACKGROUND Metal printing or additive manufacturing of metal materials has become a trend in current and future manufacturing. The existing additive manufacturing mode still focuses on melting and covering or is an extension based thereon, and has poor continuous effects. Products of additive manufacturing can only be used for reference in product design, but cannot be used on parts in a real sense to achieve the same effects as that achieved by traditional casting and forging. At present, many scholars and engineers at home and abroad are developing and researching some metal printing equipment, but most of the theories based on are still similar to those of laser welding, laser cladding, etc., which have not broken through the existing bottleneck of melting defects, resulting in poor effects of a large amount of additive manufacturing equipment. But fortunately, the control system of the existing additive manufacturing equipment is developed very well and can accurately control an addition process, and therefore, the accuracy of appearance obtained by additive manufacturing is pretty high. Based on the research of the aforementioned researchers, the present invention develops a friction stir additive manufacturing method by using a friction stir connection mode, and develops corresponding equipment based thereon. The most prominent feature of the present invention is the use of a magnetic levitation bearing to achieve high-speed rotational motion with low resistance, achieve collision friction of mixed powder in a high-speed environment, and subsequently plasticize mixed metal powder. Moreover, integration of stirring, powder mixing and addition is achieved by a magnetic levitation technology, a spindle is firstly driven to rotate through transmission of two gears, and then the rotation of the spindle is achieved by magnetic levitation, which not only greatly reduces the electricity cost, but also increases the spindle speed limited by gear transmission, thereby providing the increased speed required for friction stir addition, greatly reducing the electricity cost, and further significantly reducing the cost of friction stir additive manufacturing. The equipment developed by the present invention is simple in structure, convenient to operate, and easy to promote and apply. SUMMARY Aiming at defects such as shrinkage, porosity and looseness in the existing melting additive manufacturing process for aluminum alloy, an objective of the present invention is to design friction stir additive manufacturing equipment suitable for aluminum alloy materials. By using the equipment of the present invention, integration of powder feeding, stirring and additive manufacturing is achieved, and friction stir additive manufacturing of components and parts with different structural shapes is achieved. The technical solution of the present invention is as follows: Friction stir additive manufacturing equipment for aluminum alloy powder is provided, which includes a bed body 1, bed body linear guideways 2, columns 3, a beam 4, a working table 5, a beam linear guideway 6, a beam linear guideway hanging plate 7, a vertical guideway 8, a guideway hanging plate 9, an installation arc-shaped fixed frame 10, and a friction stir additive structural component 11. The friction stir additive structural component 11 of the friction stir additive manufacturing equipment for aluminum alloy powder includes a spindle sleeve 11-1, a spindle 11-2, a stirring rod 11-3, a head structure of a stirring head 11-4, a gear 11-5, a gear 11-6, a coupler 11-7, a motor 11-8, a stirring pot 11-9, a magnetic levitation bearing 11-10, and a metal soft connector 11-11. Spline grooves 11-1-1 are milled inside the spindle sleeve 11-1, splines 11-2-1 are milled on the spindle 11-2, and an inner hole 11-2-2 is drilled inside the spindle. Stirring blades 11-3-1 are welded to an upper part of the stirring rod 11-3, and a stirring conical rod 11-3-2 in a stirring needle and threads 11-3-3 on a surface of the stirring conical rod are arranged at a lower part of the stirring rod. An inner groove 11-4-1 is milled inside the head structure of the stirring head 11-4, milled holes 11-4-4 are drilled at a bottom of the inner groove 11-4-1, and a stirring needle shaft shoulder 11-4-2 is installed at a lower side of the inner groove 11-4-1. A groove with arc corrugation 11-4-3 is turned on a lower surface of the stirring needle shaft shoulder 11-4-2, and a stirring needle 11-4-5 is installed inside the stirring needle shaft shoulder 11-4-2. Threads 11-4-6 are turned on a surface of the stirring needle 11-4-5, and a stirring needle inner hole 11-4-7 is drilled in the stirring needle. The head structure of the stirring head 11-4 is connected to a bottom of the spindle sleeve 11-1 via a bolt 11-12. The spindle sleeve 11-1 and the spindle 11-2 are fitted mainly by the spline grooves 11-1-1 milled inside the spindle sleeve 11-1 and the splines 11-2-1 milled on the spindle 11-2. The smoothness of an internal surface of the stirring pot 11-9 used in the friction stir additive structural component 11 is required to be 0.02 or below. The friction stir additive manufacturing equipment for aluminum alloy powder is only applicable to friction stir addition of aluminum alloy, and the corresponding particle size of mixed powder in the additive manufacturing process is at a micron level. When the motor 11-8 is powered on, the coupler 11-7 connected by a bolt 11-13 drives the gear 11-6 on a shaft of the coupler, the gear 11-6 drives the meshed gear 11-5, and the gear 11-5 drives the spindle 11-2 installed thereon. A top end of the spindle 11-2 is connected to the stirring pot 11-9 via the metal soft connector 11-11. The magnetic levitation bearing 11-10 is installed at a joint between a lower end of the stirring pot 11-9 and the metal soft connector 11-11. When the stirring pot 11-9 is driven to rotate by the spindle 11-2, the gear 11-6 and the gear 11-5 are separated, and the magnetic levitation bearing 11-10 is activated to drive the stirring pot 11-9 to rotate at high speed by means of inertial magnetic field force. The stirring pot 11-9 is filled with proportioned micron-level related powder of aluminum alloy to be added and a large number of steel balls. Under high-speed rotation of the stirring pot 11-9, the steel balls continuously collide and squeeze the powder, generating frictional heat, and causing a large amount of mixed powder to be plasticized due to heating. Under high-speed rotation of the stirring pot 11-9, via the metal soft connector 11-11 connected to the stirring pot and the stirring rod 11-3 on the spindle 11-2, the mixed powder, i.e., the plasticized metal powder is centrifugally thrown and brought into the inner groove 11-4-1 milled inside the head structure of the stirring head 11-4 by sequentially using the stirring blades 11-3-1 and the stirring conical rod 11-3-2 with the threads 11-3-3 on the surface in the stirring needle. Meanwhile, the plasticized metal powder is brought to a support plate installed on a surface of the working table for stir additive manufacturing via the milled holes 11-4-4 drilled at the bottom of the inner groove 11-4-1 and the stirring needle inner hole 11-4-7 drilled in the stirring needle 11-4-5. The groove with arc corrugation 11-4-3 turned on the lower surface of the stirring needle shaft shoulder 11-4-2 and the threads 11-4-6 turned on the surface of the stirring needle 11-4-5 both play a role of frictional heat storage in the process of friction stir additive manufacturing, further helping to plasticize the mixed powder and achieve better friction stir additive manufacturing effects. When the friction stir additive structural component 11 is fixed to the installation arc-shaped fixed frame 10 by a bolt 12, during the process that the equipment performs friction stir additive manufacturing, the mixed metal powder flows to the support plate installed on the working table 5, and the friction stir additive manufacturing is achieved by the stirring needle shaft shoulder 11-4-2 and the stirring needle 11-4-5 on the head structure of the stirring head 11-4. To adapt to additive manufacturing of components and parts with different shapes, the equipment adopts a three-axis linkage structure, meaning that the movement on the x-axis is achieved by the bed body linear guideways 2 under the working table 5, the movement on the y-axis is achieved by the beam linear guideway 6, and the movement on the z-axis is achieved by the vertical guideway 8. According to different structures, four-axis, five-axis and other linkage design can be implemented on the basis of the equipment. The whole friction stir additive manufacturing process implements fully-automatic systematic tracking of the motion trajectory via a numerical control system to ensure the quality of friction stir additive manufacturing. Beneficial effects of the present invention are as follows: The present invention develops the friction stir additive manufacturing method by using the friction stir connection mode, and develops the corresponding equipment based thereon. The most prominent feature of the present invention is the use of the magnetic levitation bearing to achieve high-speed rotational motion with low resistance, achieve collision friction of the mixed powder in a high-speed environment, and subsequently plasticize the mixed metal powder. Moreover, integration of stirring, powder mixing and addition is achieved by a magnetic levitation technology, the spindle is firstly driven to rotate through transmission of two gears, and then the rotation of the spindle is achieved by magnetic levitation, which not only greatly reduces the electricity cost, but also increases the spindle speed limited by gear transmission, thereby providing the increased speed required for friction stir addition, greatly reducing the electricity cost, and further significantly reducing the cost of friction stir additive manufacturing. The present invention mainly adopts a melting additive manufacturing mode similar to laser additive manufacturing and powder feeding, but is different from laser cladding additive manufacturing, because the equipment does not achieve melting additive manufacturing but only achieves additive manufacturing when the powder is in a semi-molten state. In addition, the equipment can achieve additive manufacturing of components and parts with different shapes like ordinary laser cladding additive equipment. The equipment has the greatest advantage of overcoming the defects, such as shrinkage, porosity and looseness, of melting additive manufacturing methods such as the laser cladding additive manufacturing method. Compared to the traditional melting additive manufacturing, the present invention obtains better and more practical additive manufacturing quality, and the equipment is simple to operate, pollution-free, simple to manufacture, convenient to maintain and easy to promote and apply, and has a typical environmentally friendly additive manufacturing mode. Aluminum alloy components and parts manufactured by the friction stir additive manufacturing equipment of the present invention can replace cast parts and general forged parts, such as door handles, metal frames and other structural parts used in automobiles, which greatly improves the quality of these structural parts and ensures the service life thereof. Although the technical process is more complex, the equipment of the present invention has a simpler actual operation process, can achieve full-automatic control, and is convenient for an operator to use, simpler to program, and easy to promote in practical application. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram of an overall structure of the present invention. FIG. 2 is a schematic diagram of a friction stir additive structural component of the present invention. FIG. 3 is a schematic diagram of a spindle sleeve of the present invention. FIG. 4 is a schematic structural diagram of a spindle of the present invention. FIG. 5 is a schematic structural diagram of a stirring rod of the present invention. FIG. 6 is a schematic enlarged diagram of a head of the stirring rod of the present invention. FIG. 7 is a schematic diagram of a head structure of a stirring head of the present invention. FIG. 8 is a schematic partial enlarged diagram of the head structure of the stirring head of the present invention. FIG. 8(a) is a bottom view of the head structure of the stirring head, FIG. 8(b) is a schematic structural diagram of a stirring needle shaft shoulder, FIG. 8(c) is a top view of the head structure of the stirring head, and FIG. 8(d) is a schematic diagram of a stirring needle inner hole. FIG. 9 is a schematic structural diagram of a motor of the present invention. FIG. 10 is a schematic structural diagram of a stirring pot of the present invention. DETAILED DESCRIPTION The present invention will be further described below in conjunction with the accompanying drawings and embodiments. As shown in FIG. 1 to FIG. 10. Friction stir additive manufacturing equipment for aluminum alloy powder, which includes a bed body 1, bed body linear guideways 2, columns 3, a beam 4, a working table 5, a beam linear guideway 6, a beam linear guideway hanging plate 7, a vertical guideway 8, a vertical guideway hanging plate 9, an installation arc-shaped fixed frame 10, and a friction stir additive structural component 11, as shown in FIG. 1. The bed body linear guideways 2 are fixed to the bed body 1, and the working table 5 is installed on the bed body 1 and can move in an X direction along the bed body linear guideways 2. The columns 3 are installed at two sides of the bed body 1 and connected by the beam 4. The beam linear guideway 6 is installed on the beam 4, and the beam linear guideway hanging plate 7 is installed on the beam linear guideway 6 and can move in a Y direction along the beam linear guideway. The vertical guideway 8 is installed on the beam linear guideway hanging plate 7, and the vertical guideway hanging plate 9 is installed on the vertical guideway 8 and can move in a Z direction along the vertical guideway 8. One end of the installation arc-shaped fixed frame 10 is fixed to the vertical guideway hanging plate 9, and the other end of the installation arc-shaped fixed frame 10 is fixedly connected with the friction stir additive structural component 11. As shown in FIG. 2, the friction stir additive structural component 11 includes a spindle sleeve 11-1, a spindle 11-2, a stirring rod 11-3, a head structure of a stirring head 11-4, a driven gear 11-5, a stirring pot 11-9, a magnetic levitation bearing 11-10, and a metal soft connector 11-11. Spline grooves 11-1-1 are milled inside the spindle sleeve 11-1 (as shown in FIG. 3), splines 11-2-1 are milled on a surface of the spindle 11-2, and an inner hole 11-2-2 is drilled inside the spindle (as shown in FIG. 4). Stirring blades 11-3-1 are welded to a surface of the stirring rod 11-3, a stirring conical rod 11-3-2 is connected to one end of the stirring rod, and threads 11-3-3 are formed on a surface of the stirring conical rod 11-3-2 (as shown in FIG. 5 and FIG. 6). An inner groove 11-4-1 is milled inside the head structure of the stirring head 11-4 (as shown in FIG. 7), milled holes 11-4-4 (as shown in FIG. 8(b) and FIG. 8(d)) are drilled at a bottom of the inner groove 11-4-1 (as shown in FIG. 8(c)), and a stirring needle shaft shoulder 11-4-2 (as shown in FIG. 8(a)) is installed at a lower side of the inner groove 11-4-1. A groove with arc corrugation 11-4-3 is turned on a lower surface of the stirring needle shaft shoulder 11-4-2, and a stirring needle 11-4-5 is installed on the stirring needle shaft shoulder 11-4-2. Threads 11-4-6 are turned on a surface of the stirring needle 11-4-5 (as shown in FIG. 8(b)), and a stirring needle inner hole 11-4-7 is drilled in the stirring needle (as shown in FIG. 8(d)). The head structure of the stirring head 11-4 is connected to a bottom of the spindle sleeve 11-1 via a bolt 11-12. The spindle sleeve 11-1 and the spindle 11-2 are fitted and connected by the spline grooves 11-1-1 inside the spindle sleeve 11-1 and the splines 11-2-1 on the surface of the spindle 11-2. The driven gear 11-5 meshes with a driving gear 11-6, and a gear shaft of the driving gear 11-6 is connected with a motor 11-8 (FIG. 9) fixed to the beam 4 via a coupler 11-7. The friction stir additive structural component 11 moves to cause the driven gear 11-5 to mesh with the driving gear 11-6, the driving gear 11-6 drives the driven gear 11-5 to rotate, and the driven gear 11-5 drives the spindle 11-2 installed thereon to rotate. A top end of the spindle 11-2 is connected to the stirring pot 11-9 via the metal soft connector 11-11. The magnetic levitation bearing 11-10 is installed at a joint between a lower end of the stirring pot 11-9 and the metal soft connector 11-11. When the stirring pot 11-9 is driven to rotate by the spindle 11-2, the driving gear 11-6 and the driven gear 11-5 are separated, and the magnetic levitation bearing 11-10 is activated to drive the stirring pot 11-9 to rotate at high speed by means of inertial magnetic field force. The stirring pot 11-9 is filled with proportioned micron-level powder of aluminum alloy to be added and steel balls. Under high-speed rotation of the stirring pot 11-9, the steel balls continuously collide and squeeze the powder, generating frictional heat, and causing a large amount of mixed powder to be plasticized due to heating. Under high-speed rotation of the stirring pot 11-9, via the metal soft connector 11-11 connected to the stirring pot and the stirring rod 11-3 on the spindle 11-2, the mixed powder, i.e., the plasticized metal powder is centrifugally thrown and brought into the inner groove 11-4-1 milled inside the head structure of the stirring head 11-4 by sequentially using the stirring blades 11-3-1 and the stirring conical rod 11-3-2 with the threads 11-3-3 on the surface in the stirring needle. Meanwhile, the plasticized metal powder is brought to a support plate installed on a surface of the working table 5 for stir additive manufacturing via the milled holes 11-4-4 drilled at the bottom of the inner groove 11-4-1 and the stirring needle inner hole 11-4-7 drilled in the stirring needle 11-4-5. The groove with arc corrugation 11-4-3 turned on the lower surface of the stirring needle shaft shoulder 11-4-2 and the threads 11-4-6 turned on the surface of the stirring needle 11-4-5 both play a role of frictional heat storage in the process of friction stir additive manufacturing, further helping to plasticize the mixed powder and achieve better friction stir additive manufacturing effects. As shown in FIG. 10, the smoothness of an internal surface of the stirring pot 11-9 used in the friction stir additive structural component 11 of the friction stir additive manufacturing equipment for aluminum alloy powder is required to be 0.02 or below. The friction stir additive manufacturing equipment for aluminum alloy powder is characterized in that the equipment is only applicable to friction stir addition of aluminum alloy, and the corresponding particle size of mixed powder in the additive manufacturing process is at a micron level. The working process of the present invention is: As shown in FIG. 2 to FIG. 10, when the motor 11-8 is powered on, the coupler 11-7 connected by a bolt 11-13 drives the driving gear 11-6 on a shaft of the coupler, the driving gear 11-6 drives the meshed driven gear 11-5, and the driven gear 11-5 drives the spindle 11-2 installed thereon. The top end of the spindle 11-2 is connected to the stirring pot 11-9 via the metal soft connector 11-11. The magnetic levitation bearing 11-10 is installed at the joint between the lower end of the stirring pot 11-9 and the metal soft connector 11-11. When the stirring pot 11-9 is driven to rotate by the spindle 11-2, the driving gear 11-6 and the driven gear 11-5 are separated (the friction stir additive structural component 11 is driven by the beam linear guideway hanging plate 7 to move along the beam linear guideway 6, thereby separating the driving gear 11-6 from the driven gear 11-5), and the magnetic levitation bearing 11-10 is activated to drive the stirring pot 11-9 to rotate at high speed by means of inertial magnetic field force. The stirring pot 11-9 is filled with proportioned micron-level related powder of aluminum alloy to be added and a large number of steel balls. Under high-speed rotation of the stirring pot 11-9, the steel balls continuously collide and squeeze the powder, generating frictional heat, and causing a large amount of mixed powder to be plasticized due to heating. Under high-speed rotation of the stirring pot 11-9, via the metal soft connector 11-11 connected to the stirring pot and the stirring rod 11-3 on the spindle 11-2, the mixed powder, i.e., the plasticized metal powder is centrifugally thrown and brought into the inner groove 11-4-1 milled inside the head structure of the stirring head 11-4 by sequentially using the stirring blades 11-3-1 and the stirring conical rod 11-3-2 with the threads 11-3-3 on the surface in the stirring needle. Meanwhile, the plasticized metal powder is brought to the support plate installed on the surface of the working table for stir additive manufacturing via the milled holes 11-4-4 drilled at the bottom of the inner groove 11-4-1 and the stirring needle inner hole 11-4-7 drilled in the stirring needle 11-4-5. The groove with arc corrugation 11-4-3 turned on the lower surface of the stirring needle shaft shoulder 11-4-2 and the threads 11-4-6 turned on the surface of the stirring needle 11-4-5 both play a role of frictional heat storage in the process of friction stir additive manufacturing, further helping to plasticize the mixed powder and achieve better friction stir additive manufacturing effects. As shown in FIG. 1, FIG. 2 and FIG. 7, when the friction stir additive structural component 11 is fixed to the installation arc-shaped fixed frame 10 by a bolt 12, during the process that the equipment perfonns friction stir additive manufacturing, the mixed metal powder flows to the support plate installed on the working table 5, and the friction stir additive manufacturing is achieved by the stirring needle shaft shoulder 11-4-2 and the stirring needle 11-4-5 on the head structure of the stirring head 11-4. To adapt to additive manufacturing of components and parts with different shapes, the equipment adopts a three-axis linkage structure, meaning that the movement on the x-axis is achieved by the bed body linear guideways 2 under the working table 5, the movement on the y-axis is achieved by the beam linear guideway 6, and the movement on the z-axis is achieved by the vertical guideway 8. According to different structures, four-axis, five-axis and other linkage design can be implemented on the basis of the equipment. The whole friction stir additive manufacturing process implements fully-automatic systematic tracking of the motion trajectory via a numerical control system to ensure the quality of friction stir additive manufacturing. The parts not covered by the present invention are the same as the prior art or can be implemented using the prior art.

Claims

What is claimed is:

1. Friction stir additive manufacturing equipment for aluminum alloy powder, comprising a bed body (1), bed body linear guideways (2), columns (3), a beam (4), a working table (5), a beam linear guideway (6), a beam linear guideway hanging plate (7), a vertical guideway (8), a vertical guideway hanging plate (9), an installation arc-shaped fixed frame (10), and a friction stir additive structural component (11), wherein the bed body linear guideways (2) are fixed to the bed body (1), and the working table (5) is installed on the bed body (1) and can move in an X direction along the bed body linear guideways (2); the columns (3) are installed at two sides of the bed body (1) and connected by the beam (4); the beam linear guideway (6) is installed on the beam (4), and the beam linear guideway hanging plate (7) is installed on the beam linear guideway (6) and can move in a Y direction along the beam linear guideway; the vertical guideway (8) is installed on the beam linear guideway hanging plate (7), and the vertical guideway hanging plate (9) is installed on the vertical guideway (8) and can move in a Z direction along the vertical guideway (8); one end of the installation arc-shaped fixed frame (10) is fixed to the vertical guideway hanging plate (9), and the other end of the installation arc-shaped fixed frame (10) is fixedly connected with the friction stir additive structural component (11); the friction stir additive structural component (11) comprises a spindle sleeve (11-1), a spindle (11-2), a stirring rod (11-3), a head structure of a stirring head (11-4), a driven gear (11-5), a stirring pot (11-9), a magnetic levitation bearing (11-10), and a metal soft connector (11-11); spline grooves (11-1-1) are milled inside the spindle sleeve (11-1), splines (11-2-1) are milled on a surface of the spindle (11-2), and an inner hole (11-2-2) is drilled inside the spindle; stirring blades (11-3-1) are welded to a surface of the stirring rod (11-3), a stirring conical rod (11-3-2) is connected to one end of the stirring rod, and threads (11-3-3) are formed on a surface of the stirring conical rod (11-3-2); an inner groove (11-4-1) is milled inside the head structure of the stirring head (11-4), milled holes (11-4-4) are drilled at a bottom of the inner groove (11-4-1), and a stirring needle shaft shoulder (11-4-2) is installed at a lower side of the inner groove (11-4-1); a groove with arc corrugation (11-4-3) is turned on a lower surface of the stirring needle shaft shoulder (11-4-2), and a stirring needle (11-4-5) is installed on the stirring needle shaft shoulder (11-4-2); threads (11-4-6) are turned on a surface of the stirring needle (11-4-5), and a stirring needle inner hole (11-4-7) is drilled in the stirring needle; the head structure of the stirring head (11-4) is connected to a bottom of the spindle sleeve (11-1) via a bolt (11-12); the spindlesleeve (11-1) and the spindle (11-2) are fitted and connected by the spline grooves (11-1-1) inside the spindle sleeve (11-1) and the splines (11-2-1) on the surface of the spindle (11-2); the driven gear (11-5) meshes with a driving gear (11-6), and a gear shaft of the driving gear (11-6) is connected with a motor (11-8) via a coupler (11-7); the friction stir additive structural component (11) moves to cause the driven gear (11-5) to mesh with the driving gear (11-6), the driving gear (11-6) drives the driven gear (11-5) to rotate, and the driven gear (11-5) drives the spindle (11-2) installed thereon to rotate; a top end of the spindle (11-2) is connected to the stirring pot (11-9) via the metal soft connector (11-11); the magnetic levitation bearing (11-10) is installed at a joint between a lower end of the stirring pot (11-9) and the metal soft connector (11-11); when the stirring pot (11-9) is driven to rotate by the spindle (11-2), the driving gear (11-6) and the driven gear (11-5) are separated, and the magnetic levitation bearing (11-10) is activated to drive the stirring pot (11-9) to rotate at high speed by means of inertial magnetic field force; the stirring pot (11-9) is filled with proportioned micron-level powder of aluminum alloy to be added and steel balls; under high-speed rotation of the stirring pot (11-9), the steel balls continuously collide and squeeze the powder, generating frictional heat, and causing a large amount of mixed powder to be plasticized due to heating; under high-speed rotation of the stirring pot (11-9), via the metal soft connector (11-11) connected to the stirring pot and the stirring rod (11-3) on the spindle (11-2), the mixed powder, i.e., the plasticized metal powder is centrifugally thrown and brought into the inner groove (11-4-1) milled inside the head structure of the stirring head (11-4) by sequentially using the stirring blades (11-3-1) and the stirring conical rod (11-3-2) with the threads (11-3-3) on the surface in the stirring needle; meanwhile, the plasticized metal powder is brought to a support plate installed on a surface of the working table (5) for stir additive manufacturing via the milled holes (11-4-4) drilled at the bottom of the inner groove (11-4-1) and the stirring needle inner hole (11-4-7) drilled in the stirring needle (11-4-5); and the groove with arc corrugation (11-4-3) turned on the lower surface of the stirring needle shaft shoulder (11-4-2) and the threads (11-4-6) turned on the surface of the stirring needle (11-4-5) both play a role of frictional heat storage in the process of friction stir additive manufacturing, further helping to plasticize the mixed powder and achieve better friction stir additive manufacturing effects.

2. The friction stir additive manufacturing equipment for aluminum alloy powder according to claim 1, wherein a roughness of an internal surface of the stirring pot (11-9) used in the friction stir additive structural component (11) is required to be 0.02 microns or below.

3. The friction stir additive manufacturing equipment for aluminum alloy powder according to claim 1, wherein the equipment is only applicable to friction stir addition of aluminum alloy, and the corresponding particle size of mixed powder in the additive manufacturing process is at a micron level.

4. The friction stir additive manufacturing equipment for aluminum alloy powder according to claim 1, wherein the friction stir additive structural component (11) is fixed to the installation arc-shaped fixed frame (10) by a bolt (12); during the process that the equipment performs friction stir additive manufacturing, mixed metal powder flows to the support plate installed on the working table (5), and the friction stir additive manufacturing is achieved by the stirring needle shaft shoulder (11-4-2) and the stirring needle (11-4-5) on the head structure of the stirring head (11-4); to adapt to additive manufacturing of components and parts with different shapes, the equipment adopts a three-axis linkage structure, meaning that the movement on the x-axis is achieved by the bed body linear guideways (2) under the working table (5), the movement on the y-axis is achieved by the beam linear guideway (6), and the movement on the z-axis is achieved by the vertical guideway (8); according to different structures, four-axis, five-axis and other linkage design can be implemented on the basis of the equipment; and the whole friction stir additive manufacturing process implements fully-automatic systematic tracking of the motion trajectory via a numerical control system to ensure the quality of friction stir additive manufacturing.

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