A device and method for friction stir additive manufacturing

Abstract

The application relates to the field of additive manufacturing technology, and particularly provides a device and a method for friction-stir additive manufacturing, the device comprising a control system, an additive tool and a substrate, the control system being connected with the additive tool, and the inclination angle of the additive tool relative to the substrate being adjustable; the lower end of the additive tool is provided with a discharge port and a shaft shoulder, the discharge port outputs additive raw materials to the surface of the substrate, the shaft shoulder surrounds the discharge port, is used for rotating and rubbing the additive raw materials to obtain additive raw materials in a plastic state, and is used for compacting the additive raw materials in the plastic state; wherein the included angle between the shaft shoulder and the substrate is in a preset angle range. The device and the method for friction-stir additive manufacturing provided by the application strengthen the forging and pressing effect below the shaft shoulder, improve the driving capacity of the additive tool on the materials, make the additive body more compact, and the flash condition less likely to occur, thereby improving the performance of the additive body and the material utilization rate.

Description

Technical Field

[0001] This invention relates to the field of additive manufacturing technology, and in particular to an apparatus and method for friction stir additive manufacturing. Background Technology

[0002] Friction Stir Additive Manufacturing (FSAM) is a novel additive manufacturing technology that surpasses traditional additive manufacturing technologies that use melt forming. It has significant advantages in the manufacturing of lightweight metal structural components and is widely used in aerospace equipment manufacturing, transportation, machinery manufacturing and many other fields.

[0003] However, existing technologies mainly improve additive body performance by designing the surface features of additive tools or controlling temperature, neglecting to enhance the forging effect during the additive manufacturing process. This results in additive bodies that are not dense enough, and their performance does not meet ideal requirements. Furthermore, due to the low driving capability of additive tools, some material forms flash on both sides of the additive body, reducing material utilization.

[0004] There is currently no effective solution to the problem that additive manufacturing devices in related technologies neglect the enhancement of forging effect during the additive process and that additive tools have low material driving capability. Summary of the Invention

[0005] The present invention provides an apparatus and method for friction stir additive manufacturing, which at least solves the problems in related technologies where additive manufacturing apparatuses neglect the enhancement forging effect during the additive process and where additive tools have low driving ability for materials.

[0006] The apparatus for friction stir additive manufacturing provided in this invention includes a control system, an additive tool, and a substrate. The control system is connected to the additive tool and can adjust the tilt angle of the additive tool relative to the substrate.

[0007] The lower end of the additive manufacturing tool is provided with a discharge port and a shoulder. The discharge port outputs additive raw material to the surface of the substrate. The shoulder surrounds the discharge port and is used to rotate and rub the additive raw material to obtain additive raw material in a plastic state, and to compact the additive raw material in the plastic state.

[0008] The angle between the shoulder and the substrate is within a preset angle range.

[0009] The apparatus for friction stir additive manufacturing provided in the present invention has a preset angle range of 1°≤θ≤7°, where θ represents the included angle.

[0010] The apparatus for friction stir additive manufacturing provided in the embodiments of the present invention further includes a feeding mechanism and a drive system;

[0011] The upper end of the additive manufacturing tool is fixedly connected to the feeding mechanism;

[0012] The drive system is connected to the additive tool to drive the additive tool to rotate and perform a stirring action; the drive system is also connected to the control system to be controlled by the control system.

[0013] The apparatus for friction stir additive manufacturing provided in the present invention has a cylindrical shoulder and a discharge port, wherein the diameter of the shoulder is 4 to 30 mm larger than the diameter of the discharge port.

[0014] The apparatus for friction stir additive manufacturing provided in the present invention includes a shoulder comprising at least one of the following: a flat shoulder, a concave shoulder, and a shoulder with one or more bosses; the additive raw material comprises at least one of the following: rod-shaped additive raw material, filamentous additive raw material, and powdered additive raw material.

[0015] The method for friction stir additive manufacturing provided in this invention includes the following steps:

[0016] Feed the additive manufacturing materials into the additive tool;

[0017] The additive material is output to the surface of the substrate through the discharge port of the additive tool, and the additive material is rotated and rubbed by the shoulder around the discharge port to obtain the additive material in a plastic state.

[0018] The additive tool is controlled to maintain the target posture and move along a predetermined direction, the additive raw material in a plastic state is laid along the predetermined direction, and the additive raw material is compacted by the shoulder;

[0019] The target posture is defined as follows: the angle between the shoulder and the substrate is within a preset angle range.

[0020] The method for friction stir additive manufacturing provided in this invention further includes, before controlling the additive tool to maintain a target posture and move along a predetermined direction:

[0021] Adjust the additive tool to the target orientation;

[0022] The additive tool, having adjusted its target orientation, reaches the starting position;

[0023] Controlling the additive tool to maintain the target posture and move along a predetermined direction includes:

[0024] Control the additive tool to maintain the target posture and move it from the starting position to the ending position along a predetermined direction;

[0025] Determine whether the additive manufacturing process is complete based on the thickness and shape of the additive body;

[0026] Once additive manufacturing is complete, stop the movement of the additive manufacturing tool.

[0027] Before the additive manufacturing process is completed, the additive manufacturing tool is raised to a specified height and moved to a new starting position. The additive manufacturing tool is then controlled to maintain the target posture and move along the predetermined direction.

[0028] The method for friction stir additive manufacturing provided in this invention further includes:

[0029] Once additive manufacturing is complete, stop feeding the additive material into the additive manufacturing tool.

[0030] While the additive manufacturing process is not yet complete, the additive raw materials are continuously fed into the additive manufacturing tool.

[0031] The method for friction stir additive manufacturing provided in this invention, after adjusting the additive tool to the starting position, further includes:

[0032] A preset rotational speed is set for the rotational speed of the additive tool;

[0033] After the additive manufacturing tool reaches the preset rotational speed, the additive manufacturing tool is controlled to maintain the target posture and move along the predetermined direction.

[0034] The method for friction stir additive manufacturing provided in this invention further includes, during the process of controlling the additive tool to maintain a target posture and move along a predetermined direction:

[0035] The additive tool is controlled to move at a preset speed.

[0036] The present invention provides an apparatus and method for friction stir additive manufacturing, which solves the problems in related technologies where additive manufacturing apparatuses neglect the forging effect during the additive process and the additive tool has low driving capability for the material. It strengthens the forging effect below the shoulder and improves the driving capability of the additive tool for the material. Attached Figure Description

[0037] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention, and those skilled in the art can obtain other embodiments based on these drawings without creative effort.

[0038] Figure 1 This is a schematic diagram of an apparatus for friction stir additive manufacturing according to an embodiment of the present invention.

[0039] Figure 2 This is a flowchart of a method for friction stir additive manufacturing according to an embodiment of the present invention.

[0040] Figure 3 This is a schematic diagram of an experiment in an embodiment of the present invention.

[0041] Figure 4 This is a schematic diagram of the structure of an electronic device in an embodiment of the present invention.

[0042] The above figures include the following reference numerals:

[0043] 10—Control system; 20—Additive tool; 201—Shoulder; 202—Outlet; 30—Substrate;

[0044] 40—Feeding mechanism; 50—Additive body; 60—Worktable;

[0045] 0401—Computational unit; 0402—Read-only memory (ROM); 0403—Random access memory (RAM);

[0046] 0404—Bus; 0405—Input / Output (I / O) Interface; 0406—Input Unit; 0407—Output Unit;

[0047] 0408—Storage unit; 0409—Communication unit. Detailed Implementation

[0048] Embodiments of the present invention will now be described in more detail with reference to the accompanying drawings. While some embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the present invention. It should be understood that the drawings and embodiments of the present invention are for illustrative purposes only and are not intended to limit the scope of protection of the present invention.

[0049] The main characteristic of friction stir additive manufacturing (FSAM) is that it raises the temperature of the material to a plastic state through high-speed friction stirring, and then deposits metal layer by layer on the workpiece surface. The friction stir principle of FSAM is similar to friction stir welding (FSW), eliminating the melting and solidification processes required in traditional melt additive manufacturing, thus avoiding problems such as coarse grains, microstructure segregation, hot cracking, porosity, and high residual stress. Materials additively manufactured by FSAM develop a forging structure rather than a casting structure under thermomechanical processing, resulting in superior mechanical properties. FSAM can be used not only for additive manufacturing of structural components but also for coating, repairing, and joining metal parts.

[0050] However, existing FSAM devices primarily improve additive body performance by designing the surface features of the additive tool or controlling the temperature, neglecting to enhance the forging effect during the additive process. This results in insufficient density in the formed additive body, and its performance falls short of ideal requirements. Furthermore, due to the low driving capability of the additive tool, some material forms flash on both sides of the additive body, reducing material utilization.

[0051] Therefore, embodiments of the present invention provide an apparatus and method for friction stir additive manufacturing.

[0052] Please refer to Figure 1 As shown, the apparatus for friction stir additive manufacturing provided by the embodiment of the present invention includes a control system 10, an additive tool 20 and a substrate 30. The control system 10 is connected to the additive tool 20 and can adjust the tilt angle of the additive tool 20 relative to the substrate 30.

[0053] The lower end of the additive tool 20 is provided with a shoulder 201 and a discharge port 202. The discharge port 202 outputs additive raw material to the surface of the substrate 30. The shoulder 201 surrounds the discharge port 202 and is used to rotate and rub the additive raw material to obtain the additive raw material in a plastic state, and to compact the additive raw material in the plastic state.

[0054] The angle between the shoulder 201 and the substrate 30 is within a preset angle range.

[0055] The apparatus for friction stir additive manufacturing provided by the embodiments of the present invention enhances the forging effect below the shoulder and improves the driving ability of the additive tool on the material by setting the included angle between the shoulder and the substrate within a preset angle range, making the additive body denser and reducing flash, thereby improving the performance of the additive body and the material utilization rate.

[0056] The apparatus for friction stir additive manufacturing described above will now be described in detail:

[0057] Please refer to Figure 1As shown, the additive tool 20 tilts under the control of the control system 10;

[0058] The compacted additive material forms an additive body on the substrate 30. When the angle between the shoulder 201 and the substrate 30 is θ and the preset angle range of 0°<θ≤15° is satisfied, the additive body is subjected to pressure along the vertical direction from the additive material itself, as well as axial force provided by the additive tool.

[0059] The pressure along the high direction is concentrated below the discharge port 202 and cannot fully act on the shoulder 201; the axial component force provided by the additive tool strengthens the forging effect below the shoulder 201, which can promote close contact between the interlayer interfaces of the additive body, strengthen mechanical film breaking, and thus improve the performance of the additive body.

[0060] The pressure along the high direction is the pressure perpendicular to the surface of the substrate / additive, and this pressure is applied along the additive manufacturing direction V.

[0061] Axial component refers to the component of force that is decomposed along a specific axis under the action of certain forces. In the embodiment of the present invention, the additive tool applies a resultant force F to the additive body during the movement process. The direction of the resultant force F is consistent with the additive manufacturing direction V. The component of force F1 decomposed along the straight line perpendicular to the plane where the shoulder is located is the above-mentioned axial component. The magnitude of F1 satisfies F1=F*sinθ.

[0062] The control system 10's control over the additive tool 20 is not limited to controlling the tilt angle.

[0063] In the embodiments of the present invention, the additive tool 20 is tilted in the opposite direction of the additive manufacturing direction V. However, in practical applications, the tilting direction of the additive tool 20 may not be limited to the opposite direction of the additive manufacturing direction V, depending on the shape characteristics of the shoulder 201 and the shape requirements of the additive body.

[0064] An adjustable worktable can be used to tilt the additive tool relative to the substrate so that the angle between the shoulder and the substrate is within a preset angle range.

[0065] For example, the substrate is placed on the worktable, and the angle between the worktable and the ground can be adjusted manually or by the control system described above. When the worktable is adjusted by the control system, the additive tool is kept vertical, and the angle between the worktable and the ground is equal to the angle between the shoulder and the substrate. Furthermore, the tilt angle of the additive tool and the angle between the worktable and the ground can be adjusted and controlled simultaneously according to the actual situation.

[0066] Preferably, the preset angle range is 1°≤θ≤7°.

[0067] When 0° < θ < 1°, the shoulder does not significantly improve the compaction effect on the additive material, has a low driving force on the additive material, and is prone to forming flash on the additive body, resulting in low material utilization.

[0068] When 7°<θ≤15°, the contact area between the front edge of the shoulder and the additive body is small, resulting in low friction and hindering material flow. In contrast, the contact area between the rear edge of the shoulder and the additive body is large, making it easier for the rear edge of the shoulder to penetrate into the additive body. This causes some additive raw materials to be squeezed to the sides of the additive body, resulting in surface depressions.

[0069] Optionally, the control system includes a control unit, sensors, and a user interface.

[0070] The control unit includes a main controller and a motion controller; the main controller is responsible for the logic control and decision-making of the above-mentioned device; the motion controller is specifically used to control mechanical motion and is connected to the additive tool.

[0071] Additive manufacturing based on logic control can improve production efficiency and reduce human error.

[0072] The sensors include a position sensor, a force sensor, and a temperature sensor. The position sensor and the force sensor are mounted on the substrate, and the temperature sensor is used to detect the temperature of the additive material in a plastic state. The sensors transmit the detected data to the control unit via Ethernet or serial communication.

[0073] The user interface includes an operation panel and a software interface; the operation panel includes a touch screen and buttons for operators to input motion commands and control the motion state of the aforementioned device; the software interface is used to design, simulate and preview the additive manufacturing process, as well as to automatically monitor and adjust parameters in real time.

[0074] Optionally, embodiments of the present invention further include a feeding mechanism and a driving system. The upper end of the additive tool is fixedly connected to the feeding mechanism, and the driving system is connected to the additive tool to drive the additive tool to rotate and perform a stirring action. The driving system is also connected to the control system to be controlled by the control system.

[0075] The upper end of the additive manufacturing tool is fixedly connected to the feeding mechanism to ensure smooth feeding.

[0076] The drive system includes a motor and a spindle. The motor is connected to the additive tool via the spindle. The motor can be a servo motor, a stepper motor, or other types of motor. The motor is controlled by the aforementioned motion controller. Depending on the actual needs, the drive system can be designed as an integrated structure with the control system.

[0077] Preferably, the shoulder 201 and the discharge port 202 are cylindrical, and the diameter of the shoulder 201 is 4-30 mm larger than the diameter of the discharge port 202.

[0078] The portion of the shoulder diameter that is larger than the outlet diameter determines the contact area between the shoulder and the substrate. When matched with a preset angle range of 1°≤θ≤7°, it can better enhance the forging effect under the entire additive tool and avoid forming a loose additive body.

[0079] Optionally, the shoulder includes at least one of the following: a flat shoulder, a concave shoulder, and a shoulder with one or more bosses.

[0080] Flat shoulders provide a simple contact surface, which can generate uniform frictional heat and help plasticize and flow additive materials; concave shoulders can form a local cavity, which helps the additive materials to aggregate and the pressure to concentrate, thereby improving the bonding strength; shoulders with bosses can increase the contact area, improve the friction, and more effectively plasticize the additive materials. In addition, the design of the bosses can also promote the uniform mixing of additive materials, improve the microstructure uniformity and mechanical properties of the additive body.

[0081] It is worth noting that when there is no tilt angle between the additive tool and the substrate (no angle between the shoulder and the substrate), the use of a shoulder with a boss results in a particularly noticeable problem of insufficient density of the additive body and easy formation of flash.

[0082] Optionally, the additive raw material includes at least one of the following: rod-shaped additive raw material, filament-shaped additive raw material, and powder-shaped additive raw material.

[0083] The friction stir additive manufacturing apparatus provided by the embodiments of the present invention can be applied to various forms of additive raw materials and has good versatility.

[0084] The embodiments of this invention also provide a method for friction stir additive manufacturing, please refer to... Figure 2 As shown, it includes the following steps:

[0085] Step S100: The additive raw material is fed into the additive tool;

[0086] Step S200: Additive material is output to the surface of the substrate through the discharge port of the additive tool. The additive material is rotated and rubbed by the shoulder around the discharge port to obtain the additive material in a plastic state. Step S300: The additive tool is controlled to maintain the target posture and move along the predetermined direction to lay the additive material in the plastic state along the predetermined direction and to compact the additive material by the shoulder.

[0087] The target posture is defined as follows: the angle between the shoulder and the substrate is within a preset angle range.

[0088] The friction stir additive manufacturing method provided by the embodiments of the present invention enhances the forging effect below the shoulder by controlling the additive tool to maintain the angle between the shoulder and the substrate within a preset angle range, thereby improving the driving ability of the additive tool on the material and thus improving the performance of the additive body and the material utilization rate.

[0089] The above-mentioned friction stir additive manufacturing method will now be described in detail:

[0090] Specifically, in step S200, before controlling the additive tool to maintain the target posture and move along the predetermined direction, the above method further includes:

[0091] Adjust the additive tool to the target orientation;

[0092] The additive tool, which adjusts the target orientation, reaches the starting position.

[0093] The starting position needs to be determined based on the target shape and thickness of the additive body; adjusting the additive tool to the target posture before reaching the starting position can avoid height errors caused by tilting.

[0094] Specifically, in step S200, controlling the additive tool to maintain the target posture and move along a predetermined direction includes:

[0095] Control the additive tool to maintain the target orientation and move it from the starting position to the ending position along a predetermined direction;

[0096] The completion of additive manufacturing is determined based on the thickness and shape of the additive body; for example, methods for determination include:

[0097] The thickness and shape information of the additive material were obtained using an Artec 3D scanner, and the information was then analyzed using SOLIDWORKS software.

[0098] Alternatively, a portable coordinate measuring machine can be used to obtain the thickness and shape information of the additive body, which can then be edited and analyzed using the FARO RevEng software platform.

[0099] Operators can use other judgment methods or detection devices according to actual needs and convenient conditions. Specifically, when the thickness and shape of the additive body meet the set requirements, the additive manufacturing is completed, and the movement of the additive manufacturing tool is stopped.

[0100] If the thickness or shape of the additive does not meet the set requirements, the additive process is not yet complete. After raising the additive tool to a specified height, move it to a new starting position and continue to control the additive tool to maintain the target posture and move it in the predetermined direction.

[0101] Raising the additive manufacturing tool to a specified height can prevent the tool from squeezing the additive body during its movement to a new starting point, thereby improving the accuracy of additive manufacturing.

[0102] Preferably, the above method further includes:

[0103] Once additive manufacturing is complete, stop feeding additive materials into the additive manufacturing tool.

[0104] While the additive manufacturing process is not yet complete, the additive raw materials are continuously fed into the additive manufacturing tool.

[0105] In this process, as the additive manufacturing tool moves from the endpoint to the new starting point, the tool is controlled to not discharge material, but the additive raw materials are still continuously fed into the tool.

[0106] Rod-shaped, filament-shaped, and powdered additive raw materials are all solids and need to reach a preset plastic state before they can be compacted by the shoulder. The time it takes for the additive raw materials to reach the preset plastic state can be controlled by adjusting the rotation speed and temperature of the additive tool. By adjusting and controlling the conveying speed of the additive raw materials in combination with the rotation speed and temperature of the additive tool, it is possible to prevent the material from leaving the outlet of the additive tool, but still continuously convey the additive raw materials into the additive tool, thereby ensuring the continuity and material stability after the additive tool starts additive processing at a new starting point.

[0107] Specifically, after adjusting the additive manufacturing tool to the starting position, the above method also includes:

[0108] Set a preset rotation speed for the additive manufacturing tool;

[0109] After the additive tool reaches the preset rotational speed, the additive tool is controlled to maintain the target posture and move in a predetermined direction, thereby ensuring that the additive raw material output by the additive tool has a relatively consistent plastic state.

[0110] To achieve different plastic states, different preset rotation speeds can be set, and more precise adjustments and controls can be made in conjunction with the additive manufacturing temperature.

[0111] Specifically, in the initial stage, the additive tool is in a non-additive state before it moves to the starting position and reaches the preset speed, and no material is discharged from the outlet;

[0112] Once the preset rotation speed is reached, the additive tool remains in additive mode until it moves from the starting position to the ending position, and the discharge port continuously and stably discharges material.

[0113] If the additive manufacturing process is not completed, the additive tool remains in a non-additive state as it moves from the endpoint to the new starting point, and no material is discharged from the outlet.

[0114] It is understandable that the endpoint position of the additive manufacturing tool can be manually adjusted via buttons or automatically controlled, based on the target shape and thickness of the additive body and the real-time additive manufacturing process. Specifically, the above method also includes the following steps in controlling the additive manufacturing tool to maintain the target orientation and move along a predetermined direction:

[0115] Control the additive manufacturing tool to maintain a preset speed to ensure that the additive raw materials output by the tool are laid evenly.

[0116] For example, the embodiments of the present invention also provide experimental data of the above-described solution to verify its technical effects, as follows:

[0117] Please refer to Figure 3 As shown, the worktable 60 is kept in a horizontal position, and the feeding mechanism 40 feeds additive raw materials to the additive tool 20. Under the control of the control system, the additive tool 20 is kept tilted and moves in a predetermined direction (additive manufacturing direction) V, thereby laying and compacting the additive raw materials in a plastic state on the substrate 30 to form an additive body 50.

[0118] In this experiment, 6-series aluminum alloy bars with a diameter of 10-15 mm were used as additive raw materials. The discharge port diameter was 3-6 mm larger than the bar diameter. The angle θ between the shoulder and the substrate was 2.5°. The shoulder diameter was 5-10 mm larger than the discharge port diameter. The shoulder had two bosses with a height of 3 mm. The starting position of the additive tool was 1-2 mm above the substrate. The rotation speed was 300-400 rpm. The moving speed was 50-70 mm / min. The specified height to which the additive tool was raised was 1.5-2 mm when the additive process was not completed. The performance data of the additive body 50 are shown in Table 1.

[0119] Table 1 Performance data of additives

[0120]

[0121] Among them, X1, X2, and X3 are selected from three bottom sampling points distributed along the X-axis of the additive body 50, and Z1, Z2, and Z3 are selected from three different layer sampling points distributed along the Z-axis of the additive body 50.

[0122] Tensile strength is the maximum stress a material can withstand under tensile force without breaking.

[0123] Yield strength is the critical stress at which a material changes from elastic deformation to plastic deformation under the action of external force. When the stress reaches the yield point, the material will continue to undergo significant plastic deformation even if the external force no longer increases.

[0124] Elongation after fracture (EPF) is the elongation of the gauge length after fracture during tensile testing, representing the maximum deformation a material can withstand before fracture. A higher EPF indicates better performance under impact loads, stronger plastic deformation capacity, and smaller defects in weakly bonded areas.

[0125] Among them, the greater the tensile strength and yield strength, the better the strength and rigidity of the material; the greater the elongation after fracture, the better the plasticity and toughness of the material.

[0126] Specifically, in response to the problems that existing additive manufacturing equipment neglects the enhancement forging effect during the additive process and that the additive tool has low driving ability for the material, the performance of the additive body is evaluated based on the elongation after fracture, but it is also necessary to ensure that the additive body has a certain tensile strength and yield strength.

[0127] Specifically, since the forging effect is mainly reflected in the Z-axis direction, the three bottom sampling points X1, X2, and X3 selected in the X-axis direction are only used as a reference.

[0128] In terms of tensile strength, X1, X2, and X3 have tensile strengths of 318.517, 335.666, and 333.974 respectively when there is a 2.5° angle between the shoulder and the substrate, and 335.298, 327.614, and 336.827 respectively when there is no angle between the shoulder and the substrate. The difference is not significant.

[0129] Regarding yield strength, X1, X2, and X3 have yield strengths of 296.848, 303.516, and 304.824 respectively when there is a 2.5° angle between the shoulder and the substrate, and 299.695, 292.25, and 305.344 respectively when there is no angle between the shoulder and the substrate. The difference is not significant.

[0130] Regarding elongation after fracture, X1, X2, and X3 have elongations of 20.75, 15, and 14.875 respectively when there is a 2.5° angle between the shoulder and the substrate, and 19, 16.38, and 15.5 respectively when there is no angle between the shoulder and the substrate. The difference is not significant.

[0131] It can be seen that whether there is an angle between the shoulder and the substrate has little impact on the performance of the additive body 50 on the X-axis.

[0132] Specifically, in the Z-axis direction, when there is an angle between the shoulder and the substrate, the performance of the additive body 50 is significantly improved.

[0133] In terms of tensile strength, Z1, Z2, and Z3 have tensile strengths of 340.111, 323.321, and 323.043 respectively when there is a 2.5° angle between the shoulder and the substrate, and 318.494, 324.865, and 329.127 respectively when there is no angle between the shoulder and the substrate. The difference is not significant.

[0134] Regarding yield strength, Z1, Z2, and Z3 have yield strengths of 303.153, 289.598, and 292.714 respectively when there is a 2.5° angle between the shoulder and the substrate, and 301.924, 303.97, and 298.97 respectively when there is no angle between the shoulder and the substrate. The difference is not significant.

[0135] Regarding elongation after fracture, Z1, Z2, and Z3 have elongations of 16.875, 13.875, and 15.875 respectively when there is a 2.5° angle between the shoulder and the substrate, and 7.62, 7.25, and 6.25 respectively when there is no angle between the shoulder and the substrate. Each sampling point has a significantly larger elongation after fracture when there is a 2.5° angle between the shoulder and the substrate, which is 2.215 times, 1.914 times, and 2.54 times that when there is no angle between the shoulder and the substrate.

[0136] The above comparative data demonstrates that when there is an angle between the shoulder and the substrate, the additive material can maintain a certain strength and rigidity while possessing better plasticity and toughness, reflecting the improvement of additive material performance by the forging effect and indicating that the driving ability of the additive tool on the material has been improved.

[0137] Embodiments of the present invention also provide a non-transitory machine-readable medium storing a computer program, wherein the computer program, when executed by a computer's processor, is used to cause the computer to perform a method according to an embodiment of the present invention.

[0138] Embodiments of the present invention also provide a computer program product, including a computer program, wherein the computer program, when executed by a computer's processor, is used to cause the computer to perform the method of an embodiment of the present invention.

[0139] An embodiment of the present invention also provides an electronic device, including: at least one processor; and a memory communicatively connected to the at least one processor. The memory stores a computer program executable by the at least one processor, which, when executed by the at least one processor, causes the electronic device to perform the method of the embodiment of the present invention.

[0140] refer to Figure 4The present invention will now describe structural block diagrams of electronic devices that can serve as embodiments of the present invention, serving as examples of hardware devices applicable to various aspects of the present invention. The term "electronic device" is intended to represent various forms of digital electronic computer devices, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The components shown herein, their connections and relationships, and their functions are merely illustrative and are not intended to limit the implementation of the present invention described and / or claimed herein.

[0141] like Figure 4 As shown, the electronic device includes a computing unit 0401, which can perform various appropriate actions and processes based on a computer program stored in read-only memory (ROM) 0402 or a computer program loaded into random access memory (RAM) 0403 from storage unit 0408. The RAM 0403 may also store various programs and data required for the operation of the electronic device. The computing unit 0401, ROM 0402, and RAM 0403 are interconnected via bus 0404. An input / output (I / O) interface 0405 is also connected to bus 0404.

[0142] Multiple components in the electronic device are connected to I / O interface 0405, including: input unit 0406, output unit 0407, storage unit 0408, and communication unit 0409. Input unit 0406 can be any type of device capable of inputting information into the electronic device. Input unit 0406 can receive input digital or character information and generate key signal inputs related to user settings and / or function control of the electronic device. Output unit 0407 can be any type of device capable of presenting information and may include, but is not limited to, a display, speaker, video / audio output terminal, vibrator, and / or printer. Storage unit 0408 may include, but is not limited to, a hard disk and an optical disk. Communication unit 0409 allows the electronic device to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunications networks, and may include, but is not limited to, modems, network cards, infrared communication devices, and / or wireless communication transceivers, such as Bluetooth devices, WiFi devices, WiMax devices, cellular communication devices, and / or the like.

[0143] The computing unit 0401 can be various general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of the computing unit 0401 include, but are not limited to, CPUs, graphics processing units (GPUs), various special-purpose artificial intelligence (AI) computing units, various computing units running machine learning model algorithms, digital signal processors (DSPs), and any suitable processors, controllers, microcontrollers, etc. The computing unit 0401 performs the various methods and processes described above. For example, in some embodiments, the method embodiments of the present invention can be implemented as computer programs tangibly contained in a machine-readable medium, such as storage unit 0408. In some embodiments, part or all of the computer program can be loaded and / or installed on an electronic device via ROM 0402 and / or communication unit 0409. In some embodiments, the computing unit 0401 can be configured to perform the methods described above by any other suitable means (e.g., by means of firmware).

[0144] Computer programs for implementing the methods of embodiments of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor or controller of a general-purpose computer, special-purpose computer, or other programmable data processing apparatus, such that when executed by the processor or controller, the computer programs cause the functions / operations specified in the flowcharts and / or block diagrams to be performed. The computer programs may be executed entirely on a machine, partially on a machine, or as a standalone software package, partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

[0145] In the context of embodiments of this invention, a machine-readable medium can be a tangible medium that may contain or store a program for use by or in conjunction with an instruction execution system, apparatus, or device. A machine-readable medium can be a machine-readable signal medium or a machine-readable storage medium. A machine-readable signal medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, or infrared systems, apparatus, or devices, or any suitable combination of the foregoing. More specific examples of machine-readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing.

[0146] It should be noted that the term "comprising" and its variations used in the embodiments of this invention are open-ended, meaning "including but not limited to". The term "based on" means "at least partially based on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments". The modifications of "one" and "a plurality" mentioned in the embodiments of this invention are illustrative and not restrictive, and those skilled in the art should understand that unless explicitly indicated otherwise in the context, they should be understood as "one or more".

[0147] The user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in the embodiments of this invention are all information and data authorized by the user or fully authorized by all parties. Furthermore, the collection, use and processing of related data must comply with the relevant laws, regulations and standards of the relevant countries and regions, and corresponding operation entry points are provided for users to choose to authorize or refuse.

[0148] The steps described in the method embodiments provided by the present invention can be performed in different orders and / or in parallel. Furthermore, the method embodiments may include additional steps and / or omit the steps shown. The scope of protection of the present invention is not limited in this respect.

[0149] The term "embodiment" in this specification refers to a specific feature, structure, or characteristic described in connection with an embodiment that may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily imply the same embodiment, nor does it imply independence or alternativeity from other embodiments. The various embodiments in this specification are described in a related manner, with reference made to similar or identical parts between embodiments. In particular, for apparatus and device embodiments, since they are substantially similar to method embodiments, the description is relatively simple, and relevant details are referred to in the description of the method embodiments.

[0150] The above-described embodiments are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of protection. It should be noted that those skilled in the art can make various modifications and improvements without departing from the inventive concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims.

Claims

1. An apparatus for friction stir additive manufacturing, characterized in that, It includes a control system, an additive manufacturing tool, and a substrate. The control system is connected to the additive manufacturing tool and can adjust the tilt angle of the additive manufacturing tool relative to the substrate. The lower end of the additive manufacturing tool is provided with a discharge port and a shoulder. The discharge port outputs additive raw material to the surface of the substrate. The shoulder surrounds the discharge port and is used to rotate and rub the additive raw material to obtain additive raw material in a plastic state, and to compact the additive raw material in the plastic state. The angle between the shoulder and the substrate is within a preset angle range, which is 1°≤θ≤7°, where θ represents the included angle. The substrate is placed on a worktable, and the angle between the worktable and the ground is adjusted by a control system. The additive tool is tilted in the opposite direction to the additive manufacturing direction. The shoulder and the discharge port are cylindrical, and the diameter of the shoulder is 4~30mm larger than the diameter of the discharge port to match the preset angle range. The shoulder is a shoulder with a boss. The additive raw material is a rod-shaped additive raw material.

2. The apparatus for friction stir additive manufacturing according to claim 1, characterized in that, It also includes the feeding mechanism and drive system; The upper end of the additive manufacturing tool is fixedly connected to the feeding mechanism; The drive system is connected to the additive tool to drive the additive tool to rotate and perform a stirring action; the drive system is also connected to the control system to be controlled by the control system.

3. A method for friction stir additive manufacturing, characterized in that, Includes the following steps: Feed the additive manufacturing materials into the additive tool; The additive material is output to the surface of the substrate through the discharge port of the additive tool, and the additive material is rotated and rubbed by the shoulder around the discharge port to obtain the additive material in a plastic state. The additive tool is controlled to maintain the target posture and move along a predetermined direction, the additive raw material in a plastic state is laid along the predetermined direction, and the additive raw material is compacted by the shoulder; The target posture is as follows: the angle between the shoulder and the substrate is within a preset angle range, where the preset angle range is 1°≤θ≤7°, and θ represents the angle; the substrate is placed on the worktable, and the angle between the worktable and the ground is adjusted by the control system; the additive tool is tilted in the opposite direction to the additive manufacturing direction; the shoulder and the discharge port are cylindrical, and the diameter of the shoulder is 4~30mm larger than the diameter of the discharge port to match the preset angle range; the shoulder is a shoulder with a boss; and the additive raw material is a rod-shaped additive raw material.

4. The method for friction stir additive manufacturing according to claim 3, characterized in that, Before controlling the additive tool to maintain the target posture and move along a predetermined direction, the method further includes: Adjust the additive tool to the target orientation; The additive tool, having adjusted its target orientation, reaches the starting position; Controlling the additive tool to maintain the target posture and move along a predetermined direction includes: Control the additive tool to maintain the target posture and move it from the starting position to the ending position along a predetermined direction; Determine whether the additive manufacturing process is complete based on the thickness and shape of the additive body; Once additive manufacturing is complete, stop the movement of the additive manufacturing tool. Before the additive manufacturing process is completed, the additive manufacturing tool is raised to a specified height and moved to a new starting position. The additive manufacturing tool is then controlled to maintain the target posture and move along the predetermined direction.

5. The method for friction stir additive manufacturing according to claim 4, characterized in that, The method further includes: Once additive manufacturing is complete, stop feeding the additive material into the additive manufacturing tool. While the additive manufacturing process is not yet complete, the additive raw materials are continuously fed into the additive manufacturing tool.

6. The method for friction stir additive manufacturing according to claim 4, characterized in that, After adjusting the additive manufacturing tool to the starting position, the method further includes: A preset rotational speed is set for the rotational speed of the additive tool; After the additive manufacturing tool reaches the preset rotational speed, the additive manufacturing tool is controlled to maintain the target posture and move along the predetermined direction.

7. The method for friction stir additive manufacturing according to claim 3, characterized in that, During the process of controlling the additive tool to maintain the target posture and move along a predetermined direction, the method further includes: The additive tool is controlled to move at a preset speed.

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