Laser coaxial fuse wire additive manufacturing device and method based on double-magnetic-field cooperation

Abstract

The invention relates to the field of laser additive manufacturing, and particularly discloses a laser coaxial fuse additive manufacturing device and method based on double-magnetic-field collaboration.The laser coaxial fuse additive manufacturing device comprises a movement system, a coaxial fuse additive manufacturing system, a double-magnetic-field auxiliary system and a control monitoring system, and a wire feeding mechanism is arranged outside the device. The double-magnetic-field auxiliary system is composed of a magnetic pressure induction system and a symmetrical sliding type magnetic field generation system. The magnetic pressure sensing system is arranged around the welding head and generates a vertical magnetic field; the symmetrical sliding type magnetic field generation system generates a horizontal magnetic field through Helmholtz coils on the two sides. The two magnetic field systems are mutually independent and adjustable and form orthogonal configuration in space. The device is provided with a high-speed camera to monitor the state of the molten pool in real time, the magnetic field intensity and proportion are dynamically adjusted through a controller and double electromagnetic generators, and accurate control over molten drop transition and molten pool flowing is achieved. According to the invention, the quality and stability of coaxial fuse additive manufacturing are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of laser additive manufacturing, and in particular to a laser coaxial fuse additive manufacturing device and method based on dual magnetic field collaboration. Background Art

[0002] Laser additive manufacturing technology has been widely used in high-end manufacturing fields such as aerospace, automobile manufacturing, and shipbuilding industry due to its advantages such as high energy density, small deformation, narrow heat-affected zone, and wide applicability. However, the traditional lateral wire feeding method has problems such as unstable material deposition position, strong directional dependence, and poor process flexibility, and slight changes in the wire feeding angle will affect the deposition quality. Laser coaxial fuse technology achieves material deposition by feeding the metal wire coaxially with the laser beam, which can improve deposition efficiency and achieve precise control of composition. However, in the high-power laser coaxial fuse additive manufacturing process, the fluid dynamics behavior of the molten pool is complex, the instability problem caused by the surface tension gradient is prominent, and under high-speed deposition conditions, the depth of the molten pool is difficult to meet the process requirements.

[0003] The single magnetic field assisted laser welding technology has the following technical defects: first, the intensity and distribution of the single magnetic field are difficult to achieve precise control, resulting in poor stability of the additive manufacturing process; second, the existing magnetic field has a single mode of action, making it difficult to achieve multi-dimensional control of the molten pool flow and unable to effectively increase the molten pool depth. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides a laser coaxial fused wire additive manufacturing device and method based on dual magnetic field collaboration, which can effectively solve the problems of uneven weld formation caused by existing side-axis wire feeding, the inability of a single magnetic field to achieve multi-dimensional control, and the inability to effectively increase the depth of the molten pool.

[0005] To achieve the above-mentioned purpose, the present invention proposes a laser coaxial fuse additive manufacturing device based on dual magnetic field collaboration, the device comprising a motion system, a coaxial fuse additive manufacturing system, a dual magnetic field auxiliary system, a control and monitoring system, and a wire feeding mechanism is configured outside the device; the motion system is composed of a guide rail system and a bottom support structure; the coaxial fuse additive manufacturing system includes a support mechanism for a welding head; the dual magnetic field auxiliary system is composed of a magnetic pressure induction system and a symmetrical sliding magnetic field generating system; the control and monitoring system is composed of a high-speed camera and a controller.

[0006] Preferably, the guide rail system includes a horizontal X-guide rail and a Y-guide rail perpendicular to the horizontal X-guide rail, and is connected to a gear transmission mechanism to form an XY platform structure that moves in a horizontal plane; the guide rail system controls the vertical movement of the welding head through the Z-guide rail; the guide rail system as a whole is a three-dimensional motion control system.

[0007] Preferably, the support mechanism of the welding head is a trapezoidal metal three-dimensional structure; the support mechanism of the welding head is connected to the gear transmission mechanism of the guide rail system through a mechanical connection component to form a motion system that accurately adjusts the position of the welding head in three-dimensional space.

[0008] Preferably, the coaxial fuse welding head is fastened to the inner side of the supporting mechanism of the welding head, the welding head is connected to an external laser generator, and the laser emitter emits a high-power continuous wave laser beam into the welding head; a through coaxial shielding gas channel is arranged inside the welding head, and the coaxial shielding gas channel extends axially along the welding head, and transports the shielding gas downward to the working area; an optical system is also arranged inside the welding head, and the optical system is used to convert the incident continuous wave laser beam into a Bessel beam with an annular intensity distribution, and the optical system also includes a focusing optical mirror, which is used to focus the Bessel beam on the workpiece surface; a wire feeding channel is provided on the central axis of the welding head, and the wire feeding mechanism vertically transports the welding wire through the wire feeding channel; the conveying path of the welding wire coincides with the central axis of the welding head, so that the welding wire can accurately pass through the central area of ​​the Bessel beam; a wire feeding nozzle is installed under the mounting seat of the welding head.

[0009] Preferably, the magnetic pressure induction system is arranged around the welding head and fixed on the upper outer wall of the wire feeding nozzle, and the magnetic field action area intersects with the axis of the welding head; the magnetic pressure induction system is composed of a magnetic induction coil, a cooling guide seat, an annular magnetic pole assembly and a magnetic shielding layer; the magnetic induction coil is formed by winding an insulated coated copper wire with a rectangular cross-section, and is arranged in a radial multi-layer concentric annular structure, coaxially arranged with the welding head, each layer of coils is concentrically arranged and has the same number of turns, and a magnetic shielding layer is arranged on the outer layer; the magnetic induction coil is installed on the annular magnetic pole assembly, and the lead-out end of the magnetic induction coil is connected to the dual electromagnetic generator , the dual electromagnetic generator adjusts and controls the input power of the magnetic induction coil through a power control unit; the cooling guide seat is an annular structure, with a water inlet on the upper part and a cooling water channel inside; the annular magnetic pole assembly is made of high magnetic permeability soft magnetic material, located at the bottom of the magnetic pressure induction system, coaxial with the magnetic induction coil, and its inner diameter matches the welding head; the annular magnetic pole assembly has an annular cooling water channel inside, and a water outlet is provided at the bottom, the cooling water channel is connected to the water channel of the cooling guide seat, and the water inlet and the water outlet are connected through a water cooler to form a closed-loop cooling system; the annular magnetic pole assembly is fixed to the cooling guide seat through a detachable structure; The symmetrical sliding magnetic field generating system is composed of a bilaterally symmetrical slide rail device and an annular magnetic control symmetrical generating device; the annular magnetic control symmetrical generating device includes a coil mounting seat, which is arranged on both sides of the additive manufacturing working surface, and the central axis of the coil is parallel to the additive manufacturing direction; the coil mounting seat is made of non-magnetic material, and a Helmholtz coil is coaxially arranged inside the coil mounting seat, and an insulating gap is formed between the inner wall of the coil mounting seat and the outer wall of the Helmholtz coil; the Helmholtz coil is made of a hollow wire, and a spiral refrigeration loop for passing a cooling medium is formed inside the Helmholtz coil, and the Helmholtz coil has a spiral structure, is wound along its axial direction, and the axial direction is set at a preset angle to the additive manufacturing direction; the spiral refrigeration loop is coaxially arranged with the Helmholtz coil and extends in the spiral direction.

[0010] Preferably, the magnetic flux lines of the magnetic pressure induction system are distributed in the vertical direction, and the magnetic flux lines of the symmetrical sliding magnetic field generating system are distributed in the horizontal direction, and the two magnetic fields form an orthogonal magnetic field configuration in the molten pool area.

[0011] Preferably, the orthogonal magnetic field configuration adopts the principle of regional control, and forms a controllable and stable composite magnetic field distribution in the molten pool area by adjusting the magnetic pole position and adjusting the excitation parameters; the spatial coupling position of the orthogonal magnetic field is controlled by a magnetic field distribution measurement system; the magnetic field distribution measurement system includes a magnetic field detection device and a position recording and control system; the magnetic field detection device is composed of a three-dimensional Hall sensor array, and is installed on the slide rail device, and maintains a certain safety distance from the annular magnetically controlled symmetry generating device; the position recording and control system is provided with a data acquisition unit, and also includes a data processing module.

[0012] Preferably, the high-speed camera is fixed to the mounting base of the welding head by bolt connection, and a foldable support arm design is adopted. The support arms are interconnected by hinge nodes, bolt fastening points are arranged at key connections, and a non-interference design is adopted; the controller is used to receive the information after the high-speed camera analyzes the image obtained, and generate corresponding control instructions to control the output power and ratio of the two electromagnetic emissions in the dual electromagnetic generator for adjustment.

[0013] Preferably, the workpiece to be additively manufactured is fixed on the platform-wing bottom plate, which adopts a symmetrical double-wing design, with an independently adjustable protective plate on each side, and each protective plate has four corners provided with fixed points, so that the platform-wing bottom plate forms a semi-enclosed additive manufacturing workspace.

[0014] A laser coaxial fuse additive manufacturing method based on dual magnetic field collaboration as the device, comprising the following steps: S1. Pre-treat and install the workpiece: clean the workpiece surface to ensure there is no contaminant, fix the workpiece on the platform wing bottom plate, adjust the position of the protective plate to form a semi-enclosed additive manufacturing space, load the welding wire into the wire feeding mechanism, check the operation status of the wire feeding system, and ensure that the welding wire delivery channel is unobstructed; S2. Spatial layout and parameter setting of magnetic field generating device: First, install the Helmholtz coil so that its axis is parallel to the additive manufacturing direction and the center of the coil is coplanar with the optical axis of the laser welding head. Set a reasonable coil spacing according to the coil radius to ensure that a uniform magnetic field is formed in the additive manufacturing area. Then install the magnetic pressure induction system directly above the welding head and adjust its position so that the direction of the generated magnetic field is perpendicular to the workpiece surface. Install a magnetic shielding layer outside the magnetic field generating device, adjust the excitation parameters of the Helmholtz coil and the magnetic pressure induction system according to the process requirements, form the required horizontal and vertical magnetic fields, and maintain the orthogonal relationship between the two magnetic fields. S3. Measurement and calibration of magnetic field spatial distribution: Use magnetic field detection device to conduct comprehensive three-dimensional magnetic field distribution scanning of the additive manufacturing area, collect and analyze magnetic field strength data through position recording and control system, accurately adjust the position and angle of the Helmholtz coil according to the measurement results, and install a spiral refrigeration loop; S4. Additive manufacturing process start-up and control: Start each system component in a predetermined order, including the wire feeding mechanism, shielding gas supply, laser system, and position recording and control system; S5. Real-time monitoring and parameter optimization: The molten pool state is monitored in real time by a high-speed camera. The controller analyzes the collected image data to obtain the morphological characteristics of the molten pool. Based on the analysis results, the system dynamically adjusts the strength of the vertical and horizontal magnetic fields through dual electromagnetic generators, and uses a progressive adjustment method to ensure the stability of the additive manufacturing process and accurately control the droplet transition and molten pool flow. S6. Additive manufacturing completion and post-processing: After the additive manufacturing is completed, each system is shut down in sequence according to the established procedures, the workpiece is quality checked, and the process parameter data including magnetic field strength, laser power, and wire feeding speed are fully recorded.

[0015] Therefore, the present invention proposes a laser coaxial fuse additive manufacturing device and method based on dual magnetic field collaboration, and its beneficial effects are as follows: (1) The present invention ensures that the wire feeding direction is always coaxial with the laser beam, thus overcoming the problem of unstable droplet transport caused by changes in the wire feeding angle in traditional lateral wire feeding and improving the reliability of the welding process.

[0016] (2) The magnetic pressure induction system and the symmetrical sliding magnetic field generating system of the present invention form a dual magnetic field auxiliary system that cooperates with each other. By adjusting the reasonable ratio of the dual magnetic fields, not only the depth of the molten pool is increased, but also the technical bottleneck of the traditional single magnetic field that is difficult to achieve deep fusion welding is solved. At the same time, it can produce a stronger electromagnetic stirring effect, promote the heat and mass transfer inside the molten pool, improve the uniformity and stability of the fusion depth, and make the molten pool flow more uniform.

[0017] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a diagram of a laser coaxial fuse additive manufacturing device based on dual magnetic field collaboration according to an embodiment of the present invention; Figure 2 is a schematic structural diagram of a magnetic pressure induction system according to an embodiment of the present invention; Figure 3 2 is a schematic structural diagram of a ring-shaped magnetically controlled symmetry generating device according to an embodiment of the present invention; Figure 4 It is a schematic diagram of the current direction and magnitude of the orthogonal magnetic field system of the present invention.

[0019] Reference numerals 1. Guide rail system; 2. Gear transmission mechanism; 3. Workpiece; 4. Platform wing bottom plate; 5. Welding wire; 6. Welding head; 7. Support mechanism; 8. Magnetic pressure induction system; 9. Magnetic induction coil; 10. Cooling guide seat; 11. Annular magnetic pole assembly; 12. Water inlet; 13. Slide rail device; 14. Annular magnetic control symmetry generating device; 15. Water outlet; 16. Helmholtz coil; 17. High-speed camera; 18. Bolt; 19. Support arm; 20. Controller; 21. Dual electromagnetic generator; 22. Spiral refrigeration loop; 23. Magnetic field detection device; 24 Position recording and control system; 25. Protective plate; 26. Wire feeding mechanism; 27. Fixed point; 28. Cooler; 29. ​​Mounting seat; 30. Magnetic shielding layer; 31. Wire feeding nozzle. DETAILED DESCRIPTION

[0020] In order to make the technical solutions, advantages and purposes of the present invention clearer, the technical solutions of the embodiments of the present invention are clearly and completely described below. The described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the described embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work belong to the protection scope of this application.

[0021] Unless otherwise defined, technical or scientific terms used in the present invention shall have the common meanings understood by one having ordinary skills in the field to which the present invention belongs.

[0022] like Figure 1-Figure 4 As shown, the present invention is a laser coaxial fuse additive manufacturing device based on dual magnetic field collaboration, the device includes a motion system, a coaxial fuse additive manufacturing system, a dual magnetic field auxiliary system, a control and monitoring system, and a wire feeding mechanism is configured outside the device; the motion system is composed of a guide rail system 1 and a bottom support structure; the coaxial fuse additive manufacturing system includes a support mechanism 7 for a welding head 6; the dual magnetic field auxiliary system is composed of a magnetic pressure induction system 8 and a symmetrical sliding magnetic field generating system; the control and monitoring system is composed of a high-speed camera 17 and a controller 20.

[0023] The guide rail system 1 includes a horizontal X-guide rail and a Y-guide rail perpendicular to the X-guide rail, which are connected by a gear transmission mechanism 2 to form an XY platform structure that moves in the horizontal plane, and realizes the vertical movement of the welding head 6 through the Z-guide rail, forming a three-dimensional motion control system as a whole. The system can accurately control the position of the welding head 6 in space according to the requirements of additive manufacturing, and realize precise positioning movement in the front, back, left, right, and up and down directions.

[0024] The support mechanism 7 of the welding head 6 is a trapezoidal metal three-dimensional structure, and the support mechanism 7 of the welding head is connected to the gear transmission mechanism 2 of the guide rail system 1 through a mechanical connection component, forming a motion system that accurately adjusts the position of the welding head in three-dimensional space. The system ensures that the welding head 6 can move stably on the guide rail with the gear transmission mechanism 2, and under the movement of the gear transmission mechanism 2, ensures that the working position of the welding head 6 can be accurately aligned with the surface of the workpiece 3, and cooperates with the guide rail system 1 to achieve three-dimensional precise positioning of the welding head 6.

[0025] The coaxial fuse welding head 6 is fastened to the inner side of the welding head support mechanism 7. The welding head 6 is connected to an external laser generator. The laser emitter emits a high-power continuous wave laser beam into the welding head 6. A through coaxial shielding gas channel is arranged inside the welding head 6. The coaxial shielding gas channel extends axially along the welding head 6 to transport the shielding gas downward to the working area.

[0026] An optical system is also provided in the welding head 6, which is used to convert the incident continuous wave laser beam into a Bessel beam with a ring-shaped intensity distribution. The optical system also includes a focusing optical mirror, which is used to focus the Bessel beam on the surface of the workpiece 3, thereby realizing concentric and coaxial additive manufacturing of the welding wire 5 and the laser beam; a wire feeding channel is provided on the central axis of the welding head 6, and the wire feeding mechanism 26 vertically transports the welding wire 5 through the wire feeding channel. The conveying path of the welding wire 5 coincides with the central axis of the welding head 6, so that the welding wire can accurately pass through the central area of ​​the Bessel beam.

[0027] A wire feed nozzle 31 is installed below the mounting seat of the welding head 6. The magnetic pressure induction system 8 is fixed on the upper outer wall of the wire feed nozzle 31 and is arranged around the welding head 6. The magnetic field action area intersects with the axis of the welding head 6, so that the main magnetic induction intensity reaches the maximum value in the additive manufacturing molten pool area; the magnetic pressure induction system 8 is composed of a magnetic induction coil 9, a cooling guide seat 10, an annular magnetic pole assembly 11 and a magnetic shielding layer 30; the magnetic induction coil 9 is formed by winding an insulating coated copper wire with a rectangular cross section, and is arranged in a radial multi-layer concentric annular structure, coaxially arranged with the welding head 6, each layer of coils is concentrically arranged and has the same number of turns, and a magnetic shielding layer 30 is arranged on the outer layer to limit the range of action of the magnetic field and reduce interference with other components of the system; the magnetic induction coil 9 is installed on the annular magnetic pole assembly 11, and the lead end of the magnetic induction coil 9 is connected to the dual electromagnetic generator 21, and the dual electromagnetic generator 21 adjusts and controls the input power of the magnetic induction coil 9 through the power control unit.

[0028] The cooling guide seat 10 is an annular structure with a water inlet 12 on the top and a cooling water channel inside; the annular magnetic pole assembly 11 is made of high magnetic permeability soft magnetic material, located at the bottom of the magnetic pressure induction system 8, coaxial with the magnetic induction coil 9, used to guide the magnetic lines of force, and its inner diameter matches the welding head 6; there is an annular cooling water channel inside the annular magnetic pole assembly 11, and a water outlet 15 is provided at the bottom. The cooling water channel is connected to the water channel of the cooling guide seat 10, and the water inlet 12 and the water outlet 15 are connected through a water cooler 28 to form a closed-loop cooling system; the annular magnetic pole assembly 11 is fixed to the cooling guide seat 10 through a detachable structure.

[0029] The symmetrical sliding magnetic field generating system is composed of a bilaterally symmetrical slide rail device 13 and an annular magnetic control symmetric generating device 14; the slide rail device 13 has a linear sliding function and can realize precise positioning and adjustment; the annular magnetic control symmetric generating device 14 includes a coil mounting seat 29 and is arranged on both sides of the additive manufacturing working surface, and the central axis of the coil is parallel to the additive manufacturing direction; the coil mounting seat 29 is made of non-magnetic material, and a Helmholtz coil 16 is coaxially arranged inside the coil mounting seat 29, and an insulating gap is formed between the inner wall of the coil mounting seat 29 and the outer wall of the Helmholtz coil 16; the Helmholtz coil 16 is made of a hollow wire, and a spiral refrigeration loop 22 for passing a cooling medium is formed inside the Helmholtz coil 16, and the Helmholtz coil 16 has a spiral structure and is arranged to be wound along its axial direction, and the axial direction is set at a preset angle to the additive manufacturing direction; the spiral refrigeration loop 22 is coaxially arranged with the Helmholtz coil 16 and extends along the spiral direction.

[0030] The magnetic flux lines of the magnetic pressure induction system 8 are mainly distributed in the vertical direction, and the magnetic flux lines of the symmetrical sliding magnetic field generating system are mainly distributed in the horizontal direction. The two magnetic fields form an orthogonal magnetic field configuration in the molten pool area.

[0031] The orthogonal magnetic field configuration design makes the magnetic flux lines of the two magnetic field systems perpendicular to each other in geometric space, forming a relatively independent magnetic field action area. The orthogonal magnetic field configuration adopts the principle of regional control, and forms a controllable and stable composite magnetic field distribution in the molten pool area by adjusting the magnetic pole position and adjusting the excitation parameters.

[0032] The spatial coupling position of the orthogonal magnetic field is controlled by a magnetic field distribution measurement system, which includes a magnetic field detection device 23 and a position recording and control system 24.

[0033] The magnetic field detection device 23 is installed on the slide rail device 13 and maintains a certain safety distance from the annular magnetic control symmetry generating device 14. The magnetic field detection device 23 is composed of a three-dimensional Hall sensor array, which can simultaneously measure the three-directional magnetic field components of any point in space. The detection range covers the additive manufacturing molten pool area and its surrounding space.

[0034] The position recording and control system 24 is provided with a data acquisition unit for synchronously collecting magnetic field strength signals and position signals, with an adjustable sampling frequency, and a data processing module capable of calculating the magnetic field vector and magnetic field orthogonality at different positions in real time. The magnetic field spatial distribution data is obtained by measuring the magnetic field strength at preset spatial grid points. The angle distribution of the two magnetic field directions is calculated using the magnetic field vector analysis method. Based on the magnetic field orthogonality evaluation index, the optimal magnetic field coupling position is determined, and the calibration results are converted into position parameters of the magnetic field generating device. Finally, the optimal position parameter information is transmitted to the motion system to ensure the accuracy of the magnetic field spatial coupling position.

[0035] The high-speed camera 17 is fixed to the mounting base of the welding head 6 by bolts 18, and adopts a foldable support arm 19 design. The support arms 19 are interconnected by hinge nodes, and bolt fastening points are set at key connections to ensure stability. The non-interference design avoids mutual influence with other components of the welding head 6.

[0036] When the welding head 6 performs additive manufacturing along a preset trajectory, the high-speed camera 17 and the welding head 6 form a synchronously moving whole, always maintaining a predetermined relative position relationship. By accurately adjusting the angles of each joint of the support arm 19, the shooting field of view of the high-speed camera 17 can be accurately aligned with the molten pool area, so as to realize real-time monitoring of the morphology, size and dynamic characteristics of the molten pool during the additive manufacturing process. The high-speed camera 17 analyzes the obtained image and then transmits the information to the controller 20. The controller 20 generates corresponding control instructions to adjust the output power and ratio of the two electromagnetic emissions in the dual electromagnetic generator 21. The dual magnetic field ratio and power information are transmitted to the dual electromagnetic generator 21.

[0037] After receiving the instruction from the controller 20, the dual electromagnetic generator 21 adjusts the electromagnetic fields of the magnetic pressure induction system 8 and the symmetrical sliding magnetic field generating system respectively, independently adjusts the intensity of each electromagnetic field, realizes the proportional control of the electromagnetic field intensity, and dynamically changes the electromagnetic field ratio. The controller is used to receive the information obtained by the high-speed camera after analyzing the image, and generate corresponding control instructions to adjust the output power and ratio of the two electromagnetic emissions in the dual electromagnetic generator.

[0038] The workpiece 3 for additive manufacturing is fixed on the platform-wing bottom plate 4 at the bottom. The platform-wing bottom plate 4 adopts a symmetrical double-wing design, with an independently adjustable protective plate 25 on each side. The double-sided protective plates 25 ensure the safety and process stability of the additive manufacturing process. Fixed points 27 are set at the four corners of each protective plate 25 to make the structure more stable and reliable. The platform-wing bottom plate 4 forms a semi-enclosed additive manufacturing workspace.

[0039] A laser coaxial fuse additive manufacturing method based on dual magnetic field collaboration includes the following steps: S1. Pre-treat and install the workpiece 3: clean the workpiece surface to ensure that there is no contaminant, fix the workpiece 3 on the platform wing bottom plate 4, adjust the position of the protective plate 25 to form a semi-enclosed additive manufacturing space, load the welding wire 5 into the wire feeding mechanism, check the operation status of the wire feeding system, and ensure that the welding wire conveying channel is unobstructed; S2. Spatial layout and parameter setting of magnetic field generating device: First, install the Helmholtz coil 16 so that its axis is parallel to the additive manufacturing direction and the center of the coil is coplanar with the optical axis of the laser welding head 6. Set a reasonable coil spacing according to the coil radius to ensure that a uniform magnetic field is formed in the additive manufacturing area. Then, install the magnetic pressure induction system 8 directly above the welding head 6 and adjust its position so that the direction of the generated magnetic field is perpendicular to the workpiece surface. A magnetic shielding layer 30 is installed outside the magnetic field generating device to limit the diffusion range of the magnetic field; the excitation parameters of the Helmholtz coil 16 and the magnetic pressure induction system 8 are adjusted according to the process requirements to form the horizontal and vertical magnetic fields of the required strengths, and the orthogonal relationship between the two magnetic fields is maintained; S3. Measurement and calibration of magnetic field spatial distribution: Use magnetic field detection device 23 to conduct a comprehensive three-dimensional magnetic field distribution scan of the additive manufacturing area, collect and analyze magnetic field strength data through position recording and control system 24, and accurately adjust the position and angle of Helmholtz coil 16 according to the measurement results to ensure that the horizontal magnetic field uniformity, vertical magnetic field gradient distribution and spatial orthogonality of the two magnetic fields meet the process requirements; at the same time, install spiral refrigeration loop 22 to effectively control the temperature of the magnetic field generating device; S4, additive manufacturing process start and control: start each system component in a predetermined order, including the wire feeding mechanism 26, the shielding gas supply, the laser system, and the position recording and control system 24, to ensure the continuity and stability of the additive manufacturing process; S5. Real-time monitoring and parameter optimization: The molten pool state is monitored in real time by a high-speed camera 17, and the controller 20 analyzes the collected image data to obtain the morphological characteristics of the molten pool; based on the analysis results, the system dynamically adjusts the strength of the vertical and horizontal magnetic fields through a dual electromagnetic generator 21, and uses a progressive adjustment method to ensure the stability of the additive manufacturing process, and accurately controls the droplet transition and molten pool flow; S6. Additive manufacturing completion and post-processing: After the additive manufacturing is completed, each system is shut down in sequence according to the established procedure, the workpiece 3 is quality checked, and the process parameter data including magnetic field strength, laser power, and wire feeding speed are fully recorded.

[0040] Therefore, the present invention provides a laser coaxial fused wire additive manufacturing device and method based on dual magnetic field collaboration, so that the wire feeding direction always remains coaxial with the laser beam, overcoming the problem of unstable molten droplet transport caused by changes in the wire feeding angle in traditional lateral wire feeding, and improving the reliability of the welding process. The magnetic pressure induction system and the symmetrical sliding magnetic field generation system in the present invention form a dual magnetic field auxiliary system that cooperates with each other. By adjusting a reasonable dual magnetic field ratio, it not only increases the depth of the molten pool, but also solves the technical bottleneck that the traditional single magnetic field is difficult to achieve deep fusion welding. At the same time, it can produce a stronger electromagnetic stirring effect, promote heat and mass transfer inside the molten pool, improve the uniformity and stability of the fusion depth, and make the molten pool flow more uniformly.

[0041] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A laser coaxial fuse additive manufacturing device based on dual magnetic field collaboration, characterized in that: The device includes a motion system, a coaxial fused wire additive manufacturing system, a dual magnetic field auxiliary system, and a control and monitoring system. A wire feeding mechanism is configured outside the device; the motion system is composed of a guide rail system and a bottom support structure; the coaxial fused wire additive manufacturing system includes a support mechanism for a welding head; the dual magnetic field auxiliary system is composed of a magnetic pressure induction system and a symmetrical sliding magnetic field generating system; the control and monitoring system is composed of a high-speed camera and a controller.

2. According to the dual magnetic field synergy laser coaxial fuse additive manufacturing device of claim 1, it is characterized in that: The guide rail system includes a horizontal X-guide rail and a Y-guide rail perpendicular to the horizontal X-guide rail, and is connected with a gear transmission mechanism to form an XY platform structure that moves in a horizontal plane; the guide rail system controls the vertical movement of the welding head through the Z-guide rail; the guide rail system as a whole is a three-dimensional motion control system.

3. The laser coaxial fuse additive manufacturing device based on dual magnetic field collaboration according to claim 1 is characterized in that: The support mechanism of the welding head is a trapezoidal metal three-dimensional structure; the support mechanism of the welding head is connected to the gear transmission mechanism of the guide rail system through a mechanical connection component to form a motion system for accurately adjusting the position of the welding head in three-dimensional space.

4. The laser coaxial fuse additive manufacturing device based on dual magnetic field collaboration according to claim 1 is characterized in that: The coaxial fuse welding head is fastened to the inner side of the supporting mechanism of the welding head, and the welding head is connected to an external laser generator, and the laser emitter emits a high-power continuous wave laser beam into the welding head; a through coaxial shielding gas channel is arranged inside the welding head, and the coaxial shielding gas channel extends axially along the welding head, and the shielding gas is transported downward to the working area; an optical system is also arranged inside the welding head, and the optical system is used to convert the incident continuous wave laser beam into a Bessel beam with an annular intensity distribution, and the optical system also includes a focusing optical mirror, which is used to focus the Bessel beam on the surface of the workpiece; a wire feeding channel is arranged on the central axis of the welding head, and the wire feeding mechanism vertically transports the welding wire through the wire feeding channel; the conveying path of the welding wire coincides with the central axis of the welding head, so that the welding wire can accurately pass through the central area of ​​the Bessel beam; a wire feeding nozzle is installed under the mounting seat of the welding head.

5. The laser coaxial fuse additive manufacturing device based on dual magnetic field collaboration according to claim 1 is characterized in that: The magnetic pressure induction system is arranged around the welding head and fixed on the upper outer wall of the wire feeding nozzle, and the magnetic field action area intersects with the axis of the welding head; the magnetic pressure induction system is composed of a magnetic induction coil, a cooling guide seat, an annular magnetic pole assembly and a magnetic shielding layer; the magnetic induction coil is formed by winding an insulating coated copper wire with a rectangular cross-section, and is arranged in a radial multi-layer concentric annular structure, coaxially arranged with the welding head, each layer of coils is concentrically arranged and has the same number of turns, and a magnetic shielding layer is arranged on the outer layer; the magnetic induction coil is installed on the annular magnetic pole assembly, and the lead-out end of the magnetic induction coil is connected to the dual electromagnetic generator. The dual electromagnetic generator regulates and controls the input power of the magnetic induction coil through a power control unit; the cooling guide seat is an annular structure, with a water inlet on the upper part and a cooling water channel inside; the annular magnetic pole assembly is made of high magnetic permeability soft magnetic material, located at the bottom of the magnetic pressure induction system, coaxial with the magnetic induction coil, and its inner diameter matches the welding head; the annular magnetic pole assembly has an annular cooling water channel inside, and a water outlet is provided at the bottom, the cooling water channel is connected to the water channel of the cooling guide seat, and the water inlet and the water outlet are connected through a water cooler to form a closed-loop cooling system; the annular magnetic pole assembly is fixed to the cooling guide seat through a detachable structure; The symmetrical sliding magnetic field generating system is composed of a bilaterally symmetrical slide rail device and an annular magnetic control symmetrical generating device; the annular magnetic control symmetrical generating device includes a coil mounting seat, which is arranged on both sides of the additive manufacturing working surface, and the central axis of the coil is parallel to the additive manufacturing direction; the coil mounting seat is made of non-magnetic material, and a Helmholtz coil is coaxially arranged inside the coil mounting seat, and an insulating gap is formed between the inner wall of the coil mounting seat and the outer wall of the Helmholtz coil; the Helmholtz coil is made of a hollow wire, and a spiral refrigeration loop for passing a cooling medium is formed inside the Helmholtz coil, and the Helmholtz coil has a spiral structure, is wound along its axial direction, and the axial direction is set at a preset angle to the additive manufacturing direction; the spiral refrigeration loop is coaxially arranged with the Helmholtz coil and extends in the spiral direction.

6. The laser coaxial fuse additive manufacturing device based on dual magnetic field collaboration according to claim 1 is characterized in that: The magnetic flux lines of the magnetic pressure induction system are distributed in the vertical direction, and the magnetic flux lines of the symmetrical sliding magnetic field generating system are distributed in the horizontal direction, and the two magnetic fields form an orthogonal magnetic field configuration in the molten pool area.

7. The laser coaxial fuse additive manufacturing device based on dual magnetic field collaboration according to claim 6 is characterized in that: The orthogonal magnetic field configuration adopts the principle of regional control, and forms a controllable and stable composite magnetic field distribution in the molten pool area by adjusting the magnetic pole position and adjusting the excitation parameters; the spatial coupling position of the orthogonal magnetic field is controlled by a magnetic field distribution measurement system; the magnetic field distribution measurement system includes a magnetic field detection device and a position recording and control system; the magnetic field detection device is composed of a three-dimensional Hall sensor array, and is installed on the slide rail device, and maintains a certain safety distance from the annular magnetic control symmetry generating device; the position recording and control system is provided with a data acquisition unit and also includes a data processing module.

8. The laser coaxial fuse additive manufacturing device based on dual magnetic field collaboration according to claim 1 is characterized in that: The high-speed camera is fixed to the mounting base of the welding head by bolt connection, and adopts a folding support arm design. The support arms are connected to each other by hinge nodes, bolt fastening points are set at key connections and a non-interference design is adopted; the controller is used to receive information after the high-speed camera analyzes the image obtained, and generate corresponding control instructions to control the output power and ratio of the two electromagnetic emissions in the dual electromagnetic generator to adjust.

9. The laser coaxial fuse additive manufacturing device based on dual magnetic field collaboration according to claim 1 is characterized in that: The workpiece to be additively manufactured is fixed on the platform-wing bottom plate at the bottom. The platform-wing bottom plate adopts a symmetrical double-wing design, with an independently adjustable protective plate on each side. Fixed points are set at the four corners of each protective plate. The platform-wing bottom plate forms a semi-enclosed additive manufacturing workspace.

10. A laser coaxial fuse additive manufacturing method based on dual magnetic field collaboration according to the device of claims 1-9, characterized in that: The following steps are involved: S1. Pre-treat and install the workpiece: clean the workpiece surface to ensure there is no contaminant, fix the workpiece on the platform wing bottom plate, adjust the position of the protective plate to form a semi-enclosed additive manufacturing space, load the welding wire into the wire feeding mechanism, check the operation status of the wire feeding system, and ensure that the welding wire delivery channel is unobstructed; S2. Spatial layout and parameter setting of magnetic field generating device: First, install the Helmholtz coil so that its axis is parallel to the additive manufacturing direction and the center of the coil is coplanar with the optical axis of the laser welding head. Set a reasonable coil spacing according to the coil radius to ensure that a uniform magnetic field is formed in the additive manufacturing area. Then install the magnetic pressure induction system directly above the welding head and adjust its position so that the direction of the generated magnetic field is perpendicular to the workpiece surface. Install a magnetic shielding layer outside the magnetic field generating device, adjust the excitation parameters of the Helmholtz coil and the magnetic pressure induction system according to the process requirements, form the required horizontal and vertical magnetic fields, and maintain the orthogonal relationship between the two magnetic fields. S3. Measurement and calibration of magnetic field spatial distribution: Use magnetic field detection device to conduct comprehensive three-dimensional magnetic field distribution scanning of the additive manufacturing area, collect and analyze magnetic field strength data through position recording and control system, accurately adjust the position and angle of the Helmholtz coil according to the measurement results, and install a spiral refrigeration loop; S4. Additive manufacturing process start-up and control: Start each system component in a predetermined order, including the wire feeding mechanism, shielding gas supply, laser system, and position recording and control system; S5. Real-time monitoring and parameter optimization: The molten pool state is monitored in real time by a high-speed camera. The controller analyzes the collected image data to obtain the morphological characteristics of the molten pool. Based on the analysis results, the system dynamically adjusts the strength of the vertical and horizontal magnetic fields through dual electromagnetic generators, and uses a progressive adjustment method to ensure the stability of the additive manufacturing process and accurately control the droplet transition and molten pool flow. S6. Additive manufacturing completion and post-processing: After the additive manufacturing is completed, each system is shut down in sequence according to the established procedures, the workpiece is quality checked, and the process parameter data including magnetic field strength, laser power, and wire feeding speed are fully recorded.

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