A multi-functional multi-laser directed energy deposition system and method of controlling the same

Abstract

The application discloses a multifunctional multi-laser directional energy deposition system and a control method thereof, a multi-light-source laser module, which is used for providing any one of infrared laser, green laser and blue laser in the system to be outputted alone or any two lasers to be combined and outputted for depositing metal materials; a multi-axis linkage movement platform, which is used for realizing relative movement of the multi-light-source laser module and a substrate; a multi-material conveying module, which is used for conveying powder, wire material and protective gas to a deposition area; a multi-physical field auxiliary module, which is used for applying a magnetic field and / or an ultrasonic field to the deposition area, wherein the multi-physical field auxiliary module is arranged near the multi-light-source laser module, and the multi-physical field auxiliary module moves along with the multi-light-source laser module; an online monitoring module, which is used for collecting molten pool image information and acoustic emission signals in real time; and an integrated control module, which is used for controlling work of the modules.

Description

Technical Field

[0001] This invention relates to the field of laser additive manufacturing technology, and in particular to a multifunctional multi-laser directional energy deposition system and its control method. Background Technology

[0002] Laser Direct Energy Deposition (LDED) is an advanced additive manufacturing and remanufacturing technology. It uses a high-energy laser beam to create a molten pool on the surface of a substrate, melting and rapidly solidifying simultaneously fed metal powder or wire. This allows for layer-by-layer material deposition to form three-dimensional solid components or surface repair layers. Compared to traditional subtractive manufacturing methods, this technology offers advantages such as high forming efficiency, high material utilization, the ability to prepare functionally graded materials, manufacture complex structures, and repair and remanufacture high-value parts. It has been widely applied in aerospace, energy, and defense industries.

[0003] However, existing LDED technology still faces many limitations in terms of material applicability, consistency of forming quality, ability to deposit complex components, and process stability control. Currently, the materials that can achieve relatively stable deposition forming are mainly limited to a few types, such as 316 stainless steel, Ti6Al4V, and Inconel 718. For highly reflective materials such as copper and aluminum alloys, due to their low absorption rate of commonly used infrared laser bands, defects such as insufficient energy coupling efficiency, unstable molten pool, severe spatter, porosity, and inclusions are prone to occur during the deposition process, making it difficult to obtain stable and high-quality deposition forming results.

[0004] Furthermore, during the LDED process, the material undergoes a rapid melting-solidification-cooling thermal cycle, resulting in a significant temperature gradient and cooling rate in the molten pool region. This leads to substantial residual stress and deformation in the deposited components, making them prone to cracking. Simultaneously, the repeated thermal cycling of the metallic material during layer-by-layer deposition causes the local microstructure to experience a complex thermal history, easily forming coarse columnar crystals, non-uniform microstructure, and significant anisotropy. Consequently, the mechanical properties of the deposited components fluctuate considerably, resulting in insufficient reliability and stability.

[0005] Existing single laser heat sources are insufficient to achieve precise control over the temperature field and solidification behavior of the molten pool, which restricts the controllable fabrication of multi-material and functionally graded structures. Summary of the Invention

[0006] The purpose of this invention is to provide a multifunctional multi-laser directional energy deposition system to solve the problems mentioned in the background art.

[0007] To achieve the aforementioned objective, the present invention provides the following technical solution: A multifunctional multi-laser directional energy deposition system, including The multi-source laser module is used to provide the system with any one of infrared laser, green laser and blue laser, or any two lasers in combination, for the deposition of metallic materials. A multi-axis linkage motion platform is used to realize the relative motion between the multi-source laser module and the substrate; A multi-material delivery module is used to deliver powder, filaments, and protective gas to the deposition area; A multiphysics auxiliary module is used to apply a magnetic field and / or an ultrasonic field to the deposition area. The multiphysics auxiliary module is located near the multi-source laser module and moves as the multi-source laser module moves. The online monitoring module is used to acquire real-time image information and acoustic emission signals of the molten pool; An integrated control module is used to control the operation of the above modules.

[0008] As an improvement to the multifunctional multi-laser directional energy deposition system of the present invention, the multi-axis linkage motion platform is an eight-axis linkage motion platform based on a robotic arm-turntable structure. The eight-axis linkage motion platform includes a six-degree-of-freedom robotic arm and a dual-axis rotary table. The six-degree-of-freedom robotic arm and the dual-axis rotary table achieve bidirectional signal interaction through an integrated control module to provide eight-degree-of-freedom spatial motion. The dual-axis rotary table includes a base, a pair of support members, a work platform, and a motor. The support members are fixedly connected to the ground, and the motor is correspondingly mounted on the support members. The motor's rotating shaft is fixedly connected to the base. The work platform is mounted on the base. The work platform can rotate 360° around the center under the drive of the motor, and the forward and backward rotation range is 0°~90°.

[0009] Currently, five-axis CNC machine tools typically achieve deterministic interpolation control of spatial trajectories based on G-code. Their motion paths are pre-planned and generated in one go by computer-aided manufacturing systems. Their degrees of freedom primarily serve the limited decoupling between the tool path and the workpiece posture. However, when dealing with large, irregularly shaped components such as meter-scale propellers, rocket engine nozzles, and complex curved combustion chambers, limitations in workspace and posture coverage make it difficult to achieve integrated continuous additive manufacturing of complex surfaces. Six-axis motion systems based on industrial robotic arms, on the other hand, achieve Cartesian space trajectory control of the end effector within the joint space using inverse kinematics algorithms, offering high spatial accessibility and path flexibility. However, when manufacturing or repairing meter-scale complex curved components, since the workpiece is usually fixed, relying solely on the robotic arm to adjust the position and posture of the deposition head is easily limited by the robotic arm's reach, joint range of motion, singular configurations, and spatial interference between the robotic arm and the large component. This leads to problems such as unreachability or difficulty in maintaining a reasonable deposition posture in areas like the back side, deep cavities, inner walls, root transition zones, and locally obstructed areas.

[0010] An eight-axis linkage motion structure consisting of a six-DOF robotic arm and a dual-axis rotary table is adopted, simultaneously introducing the workpiece attitude control degree of freedom and the laser tool path control degree of freedom into the system. This transforms the machining process from trajectory control in a single reference frame to a collaborative control mode of two reference frames: the workpiece reference frame and the tool reference frame. This structure can realize the manufacturing and remanufacturing of large rotating bodies, deep cavity components, and complex irregular curved surfaces. Based on the three-dimensional model of the component to be manufactured, spatial path points for each deposition layer are generated using layer slicing and surface feature extraction methods. The target position and attitude of the coaxial dual-laser cladding head are determined according to the surface normal and path tangent of each path point. Subsequently, a joint kinematic model of the six-DOF robotic arm, the dual-axis rotary table, the cladding head, and the workpiece is established, converting each target pose into multiple sets of candidate eight-axis motion solutions for the six joint angles of the robotic arm and the two rotation angles of the dual-axis rotary table. Based on this, a redundant degree-of-freedom optimization method is adopted to maintain the predetermined working distance and laser incident direction as basic requirements. It comprehensively considers constraints such as joint limitations, singular configurations, equipment interference, continuity of motion between adjacent path points, and the motion of the robotic arm and turntable, selecting the target motion solution from multiple candidate motion solutions. Finally, the joint trajectories of the robotic arm and the rotational trajectories of the dual-axis turntable are time-parameterized and synchronously interpolated to generate an eight-axis linkage printing path for their coordinated motion. This allows the workpiece to be deposited area to be continuously adjusted to the appropriate working space of the robotic arm, achieving continuous deposition of large and complex curved surfaces.

[0011] As an improvement to the multifunctional multi-laser directional energy deposition system of the present invention, the multi-source laser module includes a coaxial dual-laser cladding head, an integrated laser, and a water-cooled machine connected to the laser; the coaxial dual-laser cladding head is fixed at the end of the six-degree-of-freedom robotic arm; the coaxial dual-laser cladding head moves in space under the drive of a multi-axis linkage motion platform; the infrared laser, blue laser, and green laser can all be optically connected to the coaxial dual-laser cladding head one or in pairs via optical fibers, so as to selectively realize the combination of infrared laser and blue laser, infrared laser and green laser, green laser and blue laser, and individual output of infrared laser, blue laser, and green laser under the control of the integrated control module.

[0012] As an improvement to the multifunctional multi-laser directional energy deposition system of the present invention, the multi-material delivery module includes a powder feeding device, a wire feeding device, and a gas supply device. The powder feeding device and the gas supply device are respectively connected to the coaxial dual-laser cladding head. The powder feeding device includes a multi-cylinder powder feeder and a powder feeding pipeline. The multi-cylinder powder feeder is connected to the coaxial dual-laser cladding head via the powder feeding pipeline and is used to transport one or more metal powders to the deposition area using carrier gas. The wire feeding device includes a wire feeder, a wire feeding nozzle, and a frame. The wire feeding nozzle is located on one side of the coaxial dual-laser cladding head, and the frame is used to support the coiled wire. The wire feeder is used for wire feeding and retraction control with external control equipment. The gas supply device includes a gas source, a solenoid valve, and a gas supply pipeline connected in sequence. The solenoid valve is electrically connected to an integrated control module, which controls the start and stop of the solenoid valve. The gas supply pipeline is connected to the multi-cylinder powder feeder and the coaxial dual-laser cladding head.

[0013] As an improvement to the multifunctional multi-laser directional energy deposition system of the present invention, the multiphysics field auxiliary module includes a follow-up synchronous auxiliary magnetic field application device and an auxiliary ultrasonic field application device. Both the auxiliary magnetic field application device and the auxiliary ultrasonic field application device are mounted on the end of a six-degree-of-freedom robotic arm via a bracket and are located near the coaxial dual-laser cladding head. They maintain a predetermined relative position and direction of action with the coaxial dual-laser cladding head to move synchronously with it, so that the magnetic field application area and the ultrasonic field application area move synchronously with the laser application area and continuously act on the current molten pool. The auxiliary magnetic field application device includes a DC power supply, an excitation coil, and an iron core. The excitation coil and the iron core are fixed at the coaxial dual-laser cladding head via a bracket. The excitation coil is fitted onto the iron core, which extends downward to the deposition area below the coaxial dual-laser cladding head. The DC power supply communicates with the excitation coil via an electrical connection.

[0014] As an improvement to the multifunctional multi-laser directional energy deposition system of the present invention, the auxiliary ultrasonic field application device includes an ultrasonic generator, a transducer, and an amplitude transformer. The ultrasonic generator is electrically connected to the transducer, and the transducer is connected to the amplitude transformer. The transducer and the amplitude transformer are mounted on the end of a six-degree-of-freedom robotic arm via a bracket and are located near the coaxial dual-laser cladding head. The ultrasonic end of the amplitude transformer faces the deposition area.

[0015] Based on this complex eight-axis linkage motion platform, traditional external field assistance methods using fixed supports or follow-up external field assistance structures implemented by independent robotic arms struggle to maintain stable spatial co-positional relationships under complex spatial trajectories. On one hand, fixed auxiliary fields suffer from positional shifts and decreased coupling efficiency when the spatial attitude of components changes; on the other hand, independent robotic arm assistance structures are prone to spatial interference and significantly increased complexity in synchronous control under eight-axis linkage path planning conditions. The follow-up synchronous multiphysics field assistance structure integrates the auxiliary magnetic field application device and the auxiliary ultrasonic field application device near the coaxial dual-laser cladding head, maintaining a predetermined relative position and direction of action with the coaxial dual-laser cladding head, and moving synchronously with it. Therefore, without the need for separate additional robotic arm path planning for the auxiliary field application device, the magnetic field and ultrasonic field application areas can continuously correspond to the current laser application area during the eight-axis linkage deposition process, and the auxiliary field application end and the molten pool can maintain a predetermined application distance. This reduces the auxiliary field offset, effect attenuation and equipment interference caused by changes in workpiece posture and deposition position, and ensures the continuity, consistency and stability of the multi-physics field effect on the dynamic molten pool.

[0016] As an improvement to the multifunctional multi-laser directional energy deposition system of the present invention, the online monitoring module includes a coaxial CCD camera, an off-axis camera, and a microphone. The coaxial CCD camera is located inside the coaxial dual-laser cladding head and couples the laser beam with the camera's visual optical path through a beam splitter for direct observation of the frontal morphology image of the molten pool. The off-axis camera is set near the coaxial dual-laser cladding head by a fixture for observing the dynamic changes of the deposition trajectory and the molten pool. The microphone is set near the coaxial dual-laser cladding head by a fixture for collecting the process acoustic signals generated by the interaction between the laser and the material. The coaxial CCD camera, off-axis camera, and microphone are respectively connected to the data processing unit of the integrated control module to realize real-time analysis and quality control of online detection data.

[0017] As an improvement to the multifunctional multi-laser directional energy deposition system of the present invention, the integrated control module includes an industrial computer, a path planning module, a motion controller, an I / O control card, a data processing unit, and an industrial Ethernet communication module.

[0018] The purpose of this invention is to provide a control method for a multifunctional multi-laser directional energy deposition system to solve the problems mentioned in the background art.

[0019] To achieve the aforementioned objective, the present invention provides the following technical solution: A control method for a multifunctional multi-laser directional energy deposition system includes the following steps: S1. Obtain a 3D model of the component to be manufactured, and generate an eight-axis linkage printing path based on the 3D model, in which the six-degree-of-freedom robotic arm and the dual-axis rotary table move in coordination; select a single output mode of infrared laser, green laser, or blue laser, or a composite output mode of any two lasers, according to the material to be deposited and the process requirements, and set the laser process parameters, magnetic field working parameters, and / or ultrasonic field working parameters; the integrated control module generates control timing instructions for laser output, material delivery, multi-physics field assistance, and online monitoring based on the eight-axis linkage printing path and the set working parameters; S2. Control the eight-axis linkage motion platform to move to a safe position, and detect whether the eight-axis linkage motion platform, the multi-source laser module, the multi-material conveying module, the multi-physics field auxiliary module, and the online monitoring module are in normal working condition; after the detection is normal, turn on the protective gas, and control the eight-axis linkage motion platform to move to the deposition start pose; S3. Perform deposition according to the eight-axis linkage printing path, control the six-degree-of-freedom robotic arm and the dual-axis rotary table to move in coordination, and start the online monitoring module according to the control timing instructions, turn on the laser output and powder or filament feeding, and start the auxiliary magnetic field application device and / or the auxiliary ultrasonic field application device; the auxiliary magnetic field application device and the auxiliary ultrasonic field application device move synchronously with the coaxial dual laser cladding head, so that the magnetic field action area and the ultrasonic field action area move synchronously with the laser action area and continuously correspond to the current molten pool; S4. During the deposition process, the online monitoring module collects real-time image information of the molten pool and process acoustic signals. The data processing unit analyzes the current deposition state based on the collected information. The integrated control module dynamically adjusts at least one of the following based on the analysis results: laser output mode, laser power, powder feeding rate, wire feeding speed, magnetic field operating parameters, and / or ultrasonic field operating parameters. When adjusting the moving speed of the eight-axis linkage motion platform, the motion timing of subsequent path segments and the control timing of each functional module are updated synchronously. S5. When the completion of single-layer deposition, path switching, or pause condition is detected, the integrated control module executes laser shutdown, powder feeding stop, wire feeding retraction, multiphysics field shutdown, online monitoring stop, motion platform repositioning, and protective gas delayed shutdown according to the control timing instructions; when an abnormal state is detected, an alarm shutdown operation is executed. S6. When there is a subsequent deposition task, control the eight-axis linkage motion platform to move to the next deposition starting pose and repeat steps S3 to S5; when there is no subsequent deposition task, end the deposition process.

[0020] As can be seen from the described technical solution, compared with the prior art, the beneficial effects of the present invention are as follows: 1. The system is equipped with a multi-source laser module, which can be used individually or in combination according to process requirements; the system is also equipped with a multi-material conveying module, including a powder feeding device and a wire feeding device. Each material conveying unit can operate independently or be combined according to process requirements to achieve flexible switching and collaborative deposition of powder / wire materials; at the same time, the system is equipped with a multi-physics field module, which is configured with non-contact auxiliary fields such as magnetic fields and ultrasonic fields. Each auxiliary field can be applied individually or in combination. This gives the system strong process adaptability and can meet the needs of composite additive manufacturing under multi-material, multi-condition, and multi-field coupling conditions. It can also effectively solve various problems in additive manufacturing, such as coarse grains, easy cracking, and anisotropy. 2. The system adopts a multi-source laser module that can output infrared laser, green laser and blue laser one or two in combination. It can use the difference in absorption characteristics of different materials by different wavelengths to control the temperature field of the molten pool, thereby improving the energy absorption rate and process stability of highly reflective materials such as copper and aluminum. It effectively solves the problems of poor wettability of molten pool, more spatter and high porosity, thus realizing high-quality and high-stability additive manufacturing and welding of such difficult-to-machine materials. 3. The system uses a multi-axis linkage motion platform and an integrated control module to achieve synchronous control of spatial attitude and motion trajectory, which can enhance the deposition flexibility and trajectory control accuracy of complex curved surfaces and rotating components, reduce forming deviations and improve the consistency of the deposition layer, thereby meeting the application requirements of additive manufacturing and remanufacturing of large and complex components. 4. During the deposition process, the system can selectively apply non-contact auxiliary fields such as magnetic fields and / or ultrasonic fields simultaneously or individually, and achieve parameter control to regulate the flow and solidification behavior of the molten pool, improve the uniformity and refinement effect of the microstructure, reduce the probability of forming defects, and thus enhance the strength, toughness and overall performance stability of the formed parts. 5. The system achieves precise and programmable conveying of various material components through a multi-cylinder powder feeder, which can support the rapid prototyping of heterogeneous materials, gradient materials and multi-material composite structures; 6. The system is equipped with an online monitoring module and a data processing unit, which can collect and analyze molten pool image information and acoustic emission signals in real time. It forms a closed-loop feedback control mechanism with the integrated control module to achieve adaptive adjustment of key process parameters, thereby improving the stability, consistency of forming and traceability of the deposition process. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the structure of a multifunctional multi-laser directional energy deposition system based on an eight-axis linkage motion platform according to the present invention; Figure 2 This is the present invention. Figure 1 Schematic diagram of the enlarged local structure Figure 1 ; Figure 3 For the present invention Figure 2 A magnified view of a portion of point A in the middle; Figure 4 For the present invention Figure 1 Schematic diagram of the enlarged local structure Figure 2 ; Figure 5 For the present invention Figure 4 A magnified view of a portion of point B in the middle; Figure 6 This is a schematic diagram of the connection method of the various components of the present invention; Figure 7 This is a schematic diagram of signal transmission in the integrated control module; Figure 8 This is a simulation diagram of the propeller eight-axis linkage laser directional energy deposition path of the present invention; Figure 9 These are photographs and metallographic images of bulk samples of high-reflectivity aluminum alloy materials prepared by the red-blue composite and coaxial powder feeding process of this invention.

[0023] The meanings of the annotations in the attached diagram are as follows: 1. Six-DOF robotic arm; 2. Dual-axis rotary table; 3. Coaxial dual-laser cladding head; 4. Integrated laser; 5. Water chiller; 6. Multi-cylinder powder feeder; 7. Air supply device; 8. Wire feeder; 9. Wire feed nozzle; 10. Frame; 11. Integrated control module; 12. DC power supply; 13. Excitation coil; 14. Iron core; 15. Ultrasonic generator; 16. Amplitude bar; 17. Transducer; 18. CCD camera; 19. Off-axis camera; 20. Microphone.

[0024] 211. Base; 212. Support platform; 213. Working platform; 214. Motor. Detailed Implementation

[0025] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0026] In the description of this application, it should be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0027] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0028] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0029] To better understand the purpose, structure, and function of this invention, the invention will be described in further detail below with reference to the accompanying drawings and embodiments.

[0030] Example 1 like Figure 1-5 As shown, a multifunctional multi-laser directional energy deposition system includes a multi-source laser module for providing the system with individual output of any one of infrared laser, green laser, and blue laser, or a combination of any two lasers, to deposit metallic materials; a multi-axis linkage motion platform for realizing the relative movement between the multi-source laser module and the substrate; a multi-material transport module for transporting protective gas, powder, and / or filaments to the deposition area; a multi-physics field auxiliary module for applying magnetic and / or ultrasonic fields to the deposition area, wherein the multi-physics field auxiliary module is located near the multi-source laser module and moves with the multi-source laser module; an online monitoring module for real-time acquisition of molten pool image information and acoustic emission signals; and an integrated control module 11 for controlling the operation of the above modules.

[0031] In this embodiment, the multi-axis linkage motion platform is an eight-axis linkage motion platform based on a robotic arm-turntable structure. The eight-axis linkage motion platform includes a six-degree-of-freedom robotic arm 1 and a dual-axis rotary table 2, wherein a base plate is fixed on the dual-axis rotary table 2; a coaxial dual laser cladding head 3 is mounted at the end of the six-degree-of-freedom robotic arm 1 and located above the dual-axis rotary table 2.

[0032] The six-degree-of-freedom robotic arm 1 and the dual-axis rotary table 2 achieve bidirectional signal interaction through the integrated control module 11, so as to provide eight-degree-of-freedom spatial motion capability according to printing requirements.

[0033] The six-degree-of-freedom robotic arm 1 can be controlled by the integrated control module 11 to realize the spatial translation and attitude adjustment of the end coaxial dual laser cladding head 3. The coaxial dual laser cladding head 3 provides six degrees of freedom of spatial motion under the drive of the robotic arm 1, and can move at any speed in the following forms: ±X direction, ±Y direction, ±Z direction, rotation around the X axis, rotation around the Y axis, rotation around the Z axis, and any combination thereof. More preferably, the six-degree-of-freedom robotic arm 1 can complete complex motion within a radius of not less than 2.1m and cover a fan-shaped range of -120° to +165° (about 285°) on the plane.

[0034] The dual-axis rotary table 2 includes a base 211, two support platforms 212, a working platform 213, and a motor 214. The two support platforms 212 are symmetrically arranged on the base 211, and the working platform 213 is arranged between the two support platforms 212. The working platform 213 can rotate 360° infinitely around the center under the drive of the motor 214. Preferably, the dual-axis rotary table 2 can perform forward and backward flipping movements under the drive of the motor 214, with a range of 0°~90° backward flipping and 0°~90° forward flipping.

[0035] The dual-axis rotary table 2 can receive control signals from the integrated control module 11 and work in conjunction with the coaxial dual laser cladding head 3 at the end of the robotic arm 1 to complete the preset printing path, thereby obtaining the target part.

[0036] Five-axis CNC machine tools, limited by their workspace and attitude coverage capabilities, are ill-suited for the integrated continuous additive manufacturing of large, irregularly shaped components such as meter-scale propellers and complex curved combustion chambers. While six-axis industrial robotic arms improve spatial accessibility, during the overall manufacturing or repair of large components, the workpiece is usually kept fixed. The robotic arm's reach, joint limitations, unusual configurations, and spatial interference with the component body lead to problems such as unreachability or difficulty in maintaining a reasonable deposition posture in the back side, deep cavity, and root transition areas.

[0037] An eight-axis linkage motion structure consisting of a six-DOF robotic arm and a dual-axis turntable is adopted, simultaneously introducing the workpiece attitude control degree of freedom and the laser tool path control degree of freedom into the system. This transforms the machining process from trajectory control in a single reference frame to a collaborative control mode of two reference frames: the workpiece reference frame and the tool reference frame. Based on the three-dimensional model of the component to be manufactured, spatial path points for each deposition layer are generated using layered slicing and surface feature extraction methods. The target position and attitude of the coaxial dual-laser cladding head are determined based on the surface normal and path tangent of each path point. Subsequently, a joint kinematic model of the six-DOF robotic arm, the dual-axis turntable, the cladding head, and the workpiece is established, converting each target pose into multiple sets of candidate eight-axis motion solutions for the six joint angles of the robotic arm and the two rotation angles of the dual-axis turntable. On this basis, a redundant degree of freedom optimization method is adopted, taking into account the predetermined working distance and laser incident direction as basic requirements, and comprehensively considering constraints such as joint limits, singular configurations, equipment interference, continuity of motion of adjacent path points, and the motion of the robotic arm and turntable, to select the target motion solution from multiple sets of candidate motion solutions. Finally, the joint trajectory of the robotic arm and the rotation trajectory of the dual-axis turntable are time-parameterized and synchronously interpolated to generate an eight-axis linkage printing path for coordinated motion of the two, so that the workpiece to be deposited area is continuously adjusted to the appropriate working space of the robotic arm, realizing the continuous deposition of large and complex curved surfaces.

[0038] The multi-source laser module includes a coaxial dual-laser cladding head 3, an integrated laser 4 (infrared laser, blue laser, and green laser), and a water-cooled unit 5 connected to the laser. The coaxial dual-laser cladding head 3 is fixed on the end flange of a six-degree-of-freedom robotic arm 1. The coaxial dual-laser cladding head 3 moves in space under the drive of the six-degree-of-freedom robotic arm 1. The red, blue, and green lasers are connected to the coaxial dual-laser cladding head 3 through optical fibers. Under the control of the integrated control module 11, the coaxial dual-laser cladding head 3 realizes the combination of infrared and blue lasers, the combination of infrared and green lasers, the combination of green and blue lasers, and the individual output of infrared, blue, and green lasers.

[0039] The integrated laser 4 is electrically connected to the integrated control module 11 and enables signal communication. During operation, the integrated control module 11 outputs a power control signal to control the laser to emit laser light. The composite laser beam is projected onto the substrate surface through the coaxial dual laser cladding head 3 to form a molten pool and melt the powder or filament fed coaxially with the laser or fed laterally, thereby achieving layer-by-layer deposition and forming.

[0040] The multi-material conveying module includes a powder feeding device, a wire feeding device, and a gas supply device 7. The powder feeding device and the gas supply device 7 are respectively connected to the coaxial dual-laser cladding head 3. The powder feeding device includes a multi-cylinder powder feeder 6 and a powder feeding pipeline. The multi-cylinder powder feeder 6 is connected to the coaxial dual-laser cladding head 3 through the powder feeding pipeline and is used to transport one or more metal powders to the deposition area using carrier gas. The wire feeding device includes a wire feeder 8, a wire feeding nozzle 9, and a frame 10. The wire feeding nozzle 9 is located on one side of the coaxial dual-laser cladding head 3, and the frame 10 is placed on the six-degree-of-freedom robotic arm 1 to carry the coiled wire. The gas supply device 7 includes a gas source, a solenoid valve, and a gas supply pipeline connected in sequence. The solenoid valve is electrically connected to an integrated control module 11, which controls the start and stop of the solenoid valve. The gas supply pipeline is connected to the multi-cylinder powder feeder 6 and the coaxial dual-laser cladding head 3.

[0041] The multi-cylinder powder feeder 6 is a rotary powder feeder. The multi-cylinder powder feeder 6 stirs and preheats the powder. The powder conveying amount of each powder cylinder per unit time can be automatically and independently controlled by the integrated control module 11. The powder conveying amount error of the multi-cylinder powder feeder 6 is less than 1%. The powder particle size range that can be conveyed is 20-300μm. It can also stir and preheat the powder, and the preheating temperature can reach 80ºC.

[0042] The wire feeder 8 has a wire feeding speed of 0.1 m / min to 10 m / min, and the speed adjustment accuracy is 0.03 m / min.

[0043] The air supply lines are connected to the multi-cylinder powder feeder 6 and the coaxial dual laser cladding head 3 respectively to provide carrier gas and central protective gas for powder conveying.

[0044] The multiphysics field auxiliary module includes a follow-up synchronous auxiliary magnetic field application device and an auxiliary ultrasonic field application device. Figure 3 , Figure 5 The auxiliary magnetic field application device and the auxiliary ultrasonic field application device are both mounted on the end of the six-degree-of-freedom robotic arm via a bracket and located near the coaxial dual-laser cladding head. They maintain a predetermined relative position and direction of action with the coaxial dual-laser cladding head, so as to move synchronously with the coaxial dual-laser cladding head. This allows the magnetic field action area and the ultrasonic field action area to move synchronously with the laser action area and continuously act on the current molten pool. The auxiliary magnetic field application device includes a DC power supply 12, an excitation coil 13, and an iron core 14. The excitation coil 13 and the iron core 14 are fixed at the coaxial dual-laser cladding head 3 via a bracket. The excitation coil 13 is fitted onto the iron core 14, and the iron core 14 extends downward to the deposition area below the coaxial dual-laser cladding head 3. The DC power supply 12 communicates with the excitation coil 13 via an electrical connection.

[0045] The auxiliary ultrasonic field application device includes an ultrasonic generator 15, a transducer 17, and an amplitude transformer 16. The ultrasonic generator 15 is electrically connected to the transducer 17, and the transducer 17 is connected to the amplitude transformer 16. The transducer 17 and the amplitude transformer 16 are mounted on the end of a six-degree-of-freedom robotic arm via a bracket and are located near the coaxial dual-laser cladding head. The ultrasonic end of the amplitude transformer faces the deposition area.

[0046] Based on this complex eight-axis linkage motion platform, traditional external field assistance methods using fixed supports or follow-up external field assistance structures implemented with independent robotic arms are difficult to maintain stable spatial co-positional relationships under complex spatial trajectories. A follow-up synchronous multi-physics field assistance structure is adopted, integrating the auxiliary magnetic field application device and the auxiliary ultrasonic field application device near the coaxial dual-laser cladding head. This ensures they maintain a predetermined relative position and direction of action with the coaxial dual-laser cladding head and move synchronously with it. Therefore, without the need for separate additional robotic arm path planning for the auxiliary field application devices, the magnetic field and ultrasonic field application areas continuously correspond to the current laser application area during the eight-axis linkage deposition process. Furthermore, a predetermined distance is maintained between the auxiliary field application end and the molten pool, reducing auxiliary field offset, effect attenuation, and equipment interference caused by changes in workpiece posture and deposition position. This ensures the continuity, consistency, and stability of the multi-physics field's effect on the dynamic molten pool.

[0047] The online monitoring module includes a coaxial CCD camera 18, an off-axis camera 19, and a microphone 20. The coaxial CCD camera 18 is located inside the coaxial dual-laser cladding head 3 and couples the laser beam with the camera's visual optical path through a beam splitter for direct observation of the frontal morphology image of the molten pool. The off-axis camera 19 is set near the coaxial dual-laser cladding head 3 by a fixture for observing the dynamic changes of the deposition trajectory and the molten pool. The microphone 20 is set near the coaxial dual-laser cladding head 3 by a fixture for collecting the process acoustic signals generated by the interaction between the laser and the material. The coaxial CCD camera 18, the off-axis camera 19, and the microphone 20 are respectively connected to the data processing unit of the integrated control module 11 to realize real-time analysis and quality control of online detection data.

[0048] The integrated control module 11 includes an industrial computer, a path planning module, a motion controller, an I / O control card, a data processing unit, and an industrial Ethernet communication module to achieve coordinated control of the above modules.

[0049] See the diagram illustrating the connection methods of the above components. Figure 6 As shown.

[0050] During operation, the integrated control module 11, following a preset eight-axis linkage printing path, process parameter sequence, and collaborative control timing, synchronously sends control commands to each controlled device via an industrial Ethernet communication module and I / O control card. This achieves spatiotemporal coordination and linkage matching of laser output, material conveying, attitude movement, and multi-physics field assistance. A schematic diagram of the signal transmission of the integrated control module 11 is shown below. Figure 7 As shown, it specifically includes: Laser power control: A 0-10V analog control signal is output to the infrared, blue, and green lasers via the analog output channel to achieve continuous and precise adjustment of the laser output power. Simultaneously, enable and emission control signals are sent to the lasers via the digital output channel, thereby enabling laser start / stop control and switching of operating states. The material delivery rate, laser power, and scanning speed are coordinated and matched according to the path segment to ensure a constant deposition rate per unit length.

[0051] Material delivery control: The powder delivery enable and rate of the powder delivery device are controlled via digital output signals. Single-cylinder or multi-cylinder combined powder delivery can be selected according to a program to achieve independent or coordinated supply of multiple material powders. Simultaneously, a 0-10V control signal is output to the wire feeder 8 via analog output signals to adjust the wire feeding speed, and wire feeding enable and start / stop control are achieved via digital output signals. The material delivery rate is coordinated with the laser power and scanning speed according to the path segment to ensure a constant deposition rate per unit length.

[0052] Gas supply device control: The opening and closing of the central protective gas solenoid valve is controlled by digital output signals to realize the start and stop of protective gas and the timing control of gas supply.

[0053] Eight-axis linkage motion control: Through the data bus, it communicates and interacts with the six-degree-of-freedom robotic arm 1 and the dual-axis rotary table 2, outputting motion trajectory and attitude commands, so that the coaxial dual laser cladding head 3 fixed at the end of the robotic arm 1 and the dual-axis rotary table 2 can achieve coordinated linkage, thereby completing the synchronous execution of the eight-degree-of-freedom spatial trajectory; during the printing process, the laser power, powder / filament feeding speed and motion speed can be linked and matched according to the path segment to ensure the continuity and consistency of the deposition process.

[0054] Multi-physics field assisted control: The start-up and operation parameters of the auxiliary magnetic field application device and the auxiliary ultrasonic field application device are controlled according to a preset timing sequence through the digital / analog output channels of the I / O control card; the multi-physics field assisted module moves synchronously with the coaxial dual laser cladding head, so that its action area and the molten pool maintain a fixed spatial orientation relationship.

[0055] A control method for a multifunctional multi-laser directional energy deposition system includes the following steps: S1. Obtain a 3D model of the component to be manufactured, and generate an eight-axis linkage printing path based on the 3D model, in which the six-degree-of-freedom robotic arm and the dual-axis rotary table move in coordination; select a single output mode of infrared laser, green laser, or blue laser, or a composite output mode of any two lasers, according to the material to be deposited and the process requirements, and set the laser process parameters, magnetic field working parameters, and / or ultrasonic field working parameters; the integrated control module generates control timing instructions for laser output, material delivery, multi-physics field assistance, and online monitoring based on the eight-axis linkage printing path and the set working parameters; S2. Control the eight-axis linkage motion platform to move to a safe position, and detect whether the eight-axis linkage motion platform, the multi-source laser module, the multi-material conveying module, the multi-physics field auxiliary module, and the online monitoring module are in normal working condition; after the detection is normal, turn on the protective gas, and control the eight-axis linkage motion platform to move to the deposition start pose; S3. Perform deposition according to the eight-axis linkage printing path, control the six-degree-of-freedom robotic arm and the dual-axis rotary table to move in coordination, and start the online monitoring module according to the control timing instructions, turn on the laser output and powder or filament feeding, and start the auxiliary magnetic field application device and / or the auxiliary ultrasonic field application device; the auxiliary magnetic field application device and the auxiliary ultrasonic field application device move synchronously with the coaxial dual laser cladding head, so that the magnetic field action area and the ultrasonic field action area move synchronously with the laser action area and continuously correspond to the current molten pool; S4. During the deposition process, the online monitoring module collects real-time image information of the molten pool and process acoustic signals. The data processing unit analyzes the current deposition state based on the collected information. The integrated control module dynamically adjusts at least one of the following based on the analysis results: laser output mode, laser power, powder feeding rate, wire feeding speed, magnetic field operating parameters, and / or ultrasonic field operating parameters. When adjusting the moving speed of the eight-axis linkage motion platform, the motion timing of subsequent path segments and the control timing of each functional module are updated synchronously. S5. When the completion of single-layer deposition, path switching, or pause condition is detected, the integrated control module executes laser shutdown, powder feeding stop, wire feeding retraction, multiphysics field shutdown, online monitoring stop, motion platform repositioning, and protective gas delayed shutdown according to the control timing instructions; when an abnormal state is detected, an alarm shutdown operation is executed. S6. When there is a subsequent deposition task, control the eight-axis linkage motion platform to move to the next deposition starting pose and repeat steps S3 to S5; when there is no subsequent deposition task, end the deposition process.

[0056] Example 2 This embodiment uses the directional energy deposition manufacturing of propellers as an example to illustrate the implementation of eight-axis linkage path planning.

[0057] First, the 3D model of the propeller is imported into the path planning module, and the surface to be deposited on the blade is extracted. Based on the preset deposition layer thickness and channel spacing, the surface to be deposited is normalized and divided into equidistant paths to generate continuous surface deposition path points. Based on the position of each path point, the surface normal, and the path tangent, the target position and attitude of the coaxial dual-laser cladding head are determined.

[0058] A six-DOF robotic arm kinematic model was established using the DH parameter method, and a two-axis rotary table kinematic model was established using a homogeneous coordinate transformation matrix. Based on the calibration relationships between the robotic arm base coordinate system, the table coordinate system, the workpiece coordinate system, and the cladding head tool coordinate system, a joint kinematic model of the robotic arm and the two-axis rotary table was established. Through joint inverse kinematics solving, a candidate eight-axis kinematic solution consisting of the six robotic arm joint angles and the two table rotation angles was obtained.

[0059] The path planning module employs a constrained nonlinear optimization algorithm, with sequential quadratic programming being the preferred choice. The optimization objective is to minimize the weighted sum of the changes in the joint angles of the robotic arm and the rotation angles of the worktable between adjacent path points. The constraints include joint limits, worktable movement range, singular configurations, working distance, laser incident angle, motion continuity, and equipment collision avoidance, to determine the target eight-axis motion solution.

[0060] During the collision detection process, a geometric envelope model is established based on the installation position and external dimensions of the end effector. The bounding box method is first used for initial collision screening, and then geometric model collision detection is performed on the positions where interference may occur. Candidate motion solutions that collide with the end effector, propeller, dual-axis rotary table, robotic arm body or peripheral equipment or have insufficient safety clearance are eliminated.

[0061] For the back side of the propeller blades, the blade root transition area, and locally obstructed areas, the rotation and oscillation angles of the dual-axis rotary table are adjusted first to bring the current deposition area into the suitable working space of the six-degree-of-freedom robotic arm. Then, the six-degree-of-freedom robotic arm adjusts the position and attitude of the end effector. For example... Figure 8 As shown, the six-degree-of-freedom robotic arm works in concert with the dual-axis rotary table, enabling the coaxial dual-laser cladding head to adjust its spatial position and attitude along the complex curved surface of the propeller, thereby ensuring continuous accessibility for processing the front, back and root transition areas of the propeller blades.

[0062] After obtaining the target eight-axis motion solution, the joint trajectory of the robotic arm and the rotation angle trajectory of the dual-axis rotary table are generated respectively. The time parameterization is performed by the S-shaped velocity planning method, and eight-axis synchronous interpolation is performed based on a unified time reference to maintain the preset scanning speed, working distance and laser incident angle. At the same time, the auxiliary magnetic field application device and the auxiliary ultrasonic field application device move synchronously with the coaxial dual laser cladding head.

[0063] Finally, the industrial control computer correlates the eight-axis linkage trajectory with the laser output mode, laser power, powder or filament feeding parameters, protective gas parameters, magnetic field parameters, ultrasonic field parameters, and online monitoring parameters to generate a propeller printing project that includes the motion trajectory, process parameters, and the start and stop sequence of each module. After the printing project passes motion simulation, collision detection, and timing verification, it responds to the printing start command, and the integrated control module automatically executes the propeller manufacturing or repair task.

[0064] Example 3 This embodiment describes a implementation of the multifunctional multi-laser directional energy deposition system using a red-blue composite laser process. This embodiment employs infrared lasers, blue lasers, and red-blue composite lasers, in conjunction with an eight-axis linkage motion platform, a powder feeding device, and a gas supply device, to achieve a stable deposition and forming process for high-reflectivity aluminum alloy materials. The wire feeding device and the multiphysics auxiliary module are not activated.

[0065] Step 1: Select a 7075 aluminum alloy substrate and fix it on the working platform of the dual-axis rotary table 2. Adjust the relative position between the coaxial dual laser cladding head 3 and the substrate so that the cladding head is located above the deposition start point. The coaxial dual laser cladding head 3 is installed at the end of the six-degree-of-freedom robotic arm 1 and is located above the substrate.

[0066] Step 2: Start the integrated laser 4 and water chiller 5 to put the multi-source laser module into working state, and the integrated control module 11 realizes the individual output and composite output of infrared laser and blue laser.

[0067] Step 3: Activate the powder feeding device and gas feeding device 7 in the multi-material conveying module. The powder feeding device is a multi-cylinder powder feeder 6. In this embodiment, only one powder feeding cylinder is activated for single-cylinder powder feeding. The powder feeding device is connected to the coaxial dual laser cladding head 3 through the powder feeding pipeline, so that the aluminum alloy powder is transported to the deposition area and enters the molten pool under the action of the carrier gas. The carrier gas flow rate is set to 4 L / min.

[0068] Step 4: Provide central protective gas to the deposition area through the gas supply device 7. The flow rate of the central protective gas is set to 10 L / min to form a stable protective atmosphere in the deposition area. Its start and stop are controlled by the integrated control module 11.

[0069] Step 5: Import the path planning file into the integrated control module 11 and run the control program, setting deposition process parameters such as laser power, powder feed rate, and scanning rate, including: The powder feeding rate was set to 2.1 g / min. When the infrared laser is output alone: ​​the power is set to 1400W, and the movement speed (i.e., scanning rate) of the six-free robotic arm 1 driving the coaxial laser melting head 3 is set to 1600 mm / min; When blue laser is output alone: ​​power is set to 900W, and scanning rate is set to 1200 mm / min; When red and blue lasers are combined for output: the infrared laser power is set to 200 W and the blue laser power is set to 700 W, that is, the scanning rate is set to 1500 mm / min.

[0070] Step Six: The integrated control module 11 synchronously outputs laser power control signals, powder feeding control signals, and gas supply control signals according to the preset printing path, realizing the automated execution of the deposition process; during the deposition process, the six-degree-of-freedom robotic arm 1 drives the coaxial dual-laser cladding head 3 to move spatially along the preset path, while the dual-axis rotating stage 2 remains horizontal, completing the printing of the aluminum alloy deposition block sample. Figure 9 In this embodiment, infrared laser (a), blue laser (b), and red-blue composite laser (c) were used to print block samples of high-reflectivity aluminum alloy material, i.e., the corresponding metallographic images.

[0071] Step 7: Repeat steps 1 through 6 until deposition is complete.

[0072] Example 4 This embodiment describes the process of preparing metallic materials using a multi-physics field-assisted module in a multi-functional multi-laser directional energy deposition system. Based on this complex eight-axis linkage motion platform, traditional external field assistance methods using fixed supports or follow-up external field assistance structures using independent robotic arms are difficult to maintain a stable spatial co-position relationship under complex spatial trajectories. This application utilizes a follow-up synchronous auxiliary magnetic field application device and an auxiliary ultrasonic field application device to solve the above-mentioned technical problems.

[0073] Step 1: As Figure 2 As shown, the auxiliary magnetic field application device and the auxiliary ultrasonic field application device are mounted on the end of the six-degree-of-freedom robotic arm 1 via a bracket and located near the coaxial dual-laser cladding head 3, so that they maintain a predetermined relative position and direction of action with the coaxial dual-laser cladding head 3, respectively. The substrate is fixed on the working platform of the dual-axis rotary stage 2, and the six-degree-of-freedom robotic arm 1 and the dual-axis rotary stage 2 are adjusted so that the coaxial dual-laser cladding head 3 is located at the deposition start position.

[0074] Step 2: Import the preset printing path file into the integrated control module 11 and set the deposition process parameters, including laser power, scanning rate, powder feeding rate, carrier gas flow rate and center protection gas flow rate, etc.; the control method of the multi-source laser module, multi-material delivery module and gas delivery device 7 shall be executed in accordance with Example 3.

[0075] Step 3: Set the operating current of the excitation coil 13 of the auxiliary magnetic field application device to 1–15 A to form an adjustable intensity directional magnetic field; more preferably, the operating current of the excitation coil 13 is set to 3–10 A. During the deposition process, the excitation coil 13 generates a magnetic field under the drive of the DC power supply 12. The magnetic field covers the molten pool and its adjacent area, and remains aligned with the coaxial dual-laser cladding head 3 to electromagnetically control the flow and solidification process of the molten pool.

[0076] Step 4: Activate the auxiliary ultrasonic field application device, set the working frequency of the ultrasonic generator 15 to 20-55kHz, the ultrasonic generator 15 outputs a high-frequency electrical signal, the transducer 17 converts the high-frequency electrical signal into mechanical vibration, and the amplitude transformer 16 adjusts and transmits the amplitude of the mechanical vibration to promote molten pool flow, improve grain structure and enhance the stability of the molten pool.

[0077] Step 5: Activate the multi-source laser module, multi-material delivery module, gas supply device 7, auxiliary magnetic field application device, and auxiliary ultrasonic field application device. The integrated control module 11 executes the deposition process according to the preset printing path and process parameter sequence, synchronizing laser energy input, material delivery, protective gas supply, and eight-axis linkage motion to complete the layer-by-layer deposition of metallic materials. Compared with Example 3, the difference in this example is that the auxiliary magnetic field application device and the auxiliary ultrasonic field application device are activated simultaneously during the deposition process to achieve multi-physics field synergistic assisted deposition.

[0078] Example 4 This embodiment describes the usage and operation of the online monitoring module of a multifunctional multi-laser directional energy deposition system. During deposition, the online monitoring module and the integrated control module 11 work together to collect, analyze, and provide feedback control of the melt pool state in real time through multiple sensor units, thereby achieving online monitoring and stability control of the deposition process, as detailed below: Step 1: Before deposition begins, the sensor unit of the online monitoring module is arranged near the coaxial dual-laser cladding head, including a microphone 20, a coaxial camera 18, and an off-axis camera 19; the coaxial integrated high-speed CMOS camera 18 acquires images of the front of the molten pool at a frame rate of 30 Hz; the off-axis camera 19 acquires dynamic images of the molten pool area at a frame rate of 60 Hz; the microphone 20 is placed near the laser nozzle, with a frequency response range of 50–20000 Hz and a sampling rate of 48000 Hz.

[0079] Step 2: During the deposition process, the acoustic signals generated by the interaction between the laser and the material are collected in real time through the microphone 20. At the same time, the images of the molten pool and the deposition trajectory are collected synchronously through the coaxial camera 18 and the off-axis camera 19, forming a real-time data stream of acoustic and optical sources.

[0080] Step 3: The acoustic signal and image signal are transmitted in real time to the data processing unit of the integrated control module 11. The data is then processed for time synchronization, filtering and noise reduction, and formatting to obtain real-time input data that can be used for analysis.

[0081] Step 4: The data processing unit runs the molten pool feature extraction algorithm to analyze the real-time data. Preferably, a machine learning-based model algorithm (such as a trained convolutional neural network CNN) is used to extract feature parameters such as molten pool width, length, area and brightness distribution from the image, and combines acoustic signals to extract energy, main frequency or frequency band features to achieve online identification of the molten pool state.

[0082] Step 5: Compare the extracted molten pool feature parameters with the preset process window threshold to determine whether the molten pool state is within the set range; when abnormal deviations are detected in the molten pool size, stability index or spatter characteristics, generate the corresponding abnormal judgment result and adjustment requirements.

[0083] Step 6: Based on the anomaly determination results, dynamically adjust the laser output mode, laser power, powder feeding rate, wire feeding speed, magnetic field working parameters and / or ultrasonic field working parameters to bring the molten pool state back to the process window range. Step 7: Repeat steps 1 through 6 until deposition is complete.

[0084] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. Furthermore, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A multifunctional multi-laser directional energy deposition system, characterized in that, include The multi-source laser module is used to provide the system with any one of infrared laser, green laser and blue laser, or any two lasers in combination, for the deposition of metallic materials. A multi-axis linkage motion platform is used to realize the relative motion between the multi-source laser module and the substrate; A multi-material delivery module is used to deliver powder, filaments, and protective gas to the deposition area; A multiphysics auxiliary module is used to apply a magnetic field and / or an ultrasonic field to the deposition area. The multiphysics auxiliary module is located near the multi-source laser module and moves as the multi-source laser module moves. The online monitoring module is used to acquire real-time image information and acoustic emission signals of the molten pool; An integrated control module is used to control the operation of the above modules.

2. The multifunctional multi-laser directional energy deposition system according to claim 1, characterized in that, The multi-axis linkage motion platform is an eight-axis linkage motion platform based on a robotic arm-turntable structure. The eight-axis linkage motion platform includes a six-degree-of-freedom robotic arm and a dual-axis rotary table. The six-degree-of-freedom robotic arm and the dual-axis rotary table achieve bidirectional signal interaction through an integrated control module to provide eight degrees of freedom of spatial motion. The dual-axis rotary table includes a base, a pair of support members, a work platform, and a motor. The support members are fixedly connected to the ground, and the motor is correspondingly mounted on the support members. The motor's rotating shaft is fixedly connected to the base. The work platform is mounted on the base. The work platform can rotate 360° around the center under the drive of the motor, and the forward and backward rotation range is 0°~90°.

3. The multifunctional multi-laser directional energy deposition system according to claim 2, characterized in that, The multi-source laser module includes a coaxial dual-laser cladding head, an integrated laser, and a water-cooled unit connected to the laser. The coaxial dual-laser cladding head is fixed to the end of the six-degree-of-freedom robotic arm. The infrared laser, blue laser, and green laser can all be optically connected to the coaxial dual-laser cladding head, either individually or in pairs, via optical fibers. Under the control of the integrated control module, they can selectively achieve the combination of infrared and blue lasers, infrared and green lasers, and green and blue lasers, as well as the individual output of infrared, blue, and green lasers.

4. The multifunctional multi-laser directional energy deposition system according to claim 3, characterized in that, The multi-material conveying module includes a powder feeding device, a wire feeding device, and a gas supply device. The powder feeding device and the gas supply device are respectively connected to the coaxial dual-laser cladding head. The powder feeding device includes a multi-cylinder powder feeder and a powder feeding pipeline. The multi-cylinder powder feeder is connected to the coaxial dual-laser cladding head through the powder feeding pipeline and is used to transport one or more metal powders to the deposition area using carrier gas. The wire feeding device includes a wire feeder, a wire feeding nozzle, and a frame. The wire feeding nozzle is located on one side of the coaxial dual-laser cladding head, and the frame is used to support the coiled wire. The wire feeder is used to control the wire conveying and retraction with external control equipment. The gas supply device includes a gas source, a solenoid valve, and a gas supply pipeline connected in sequence. The solenoid valve is electrically connected to an integrated control module, which controls the start and stop of the solenoid valve. The gas supply pipeline is connected to the multi-cylinder powder feeder and the coaxial dual-laser cladding head.

5. The multifunctional multi-laser directional energy deposition system according to claim 1, characterized in that, The multiphysics field auxiliary module includes a follow-up synchronous auxiliary magnetic field application device and an auxiliary ultrasonic field application device. Both the auxiliary magnetic field application device and the auxiliary ultrasonic field application device are mounted on the end of the six-degree-of-freedom robotic arm via a bracket and are located near the coaxial dual-laser cladding head. They maintain a predetermined relative position and direction of action with the coaxial dual-laser cladding head to move synchronously with it. This allows the magnetic field application area and the ultrasonic field application area to move synchronously with the laser application area and continuously act on the current molten pool. The auxiliary magnetic field application device includes a DC power supply, an excitation coil, and an iron core. The excitation coil and the iron core are fixed at the coaxial dual-laser cladding head via a bracket. The excitation coil is fitted onto the iron core, which extends downward to the deposition area below the coaxial dual-laser cladding head. The DC power supply communicates with the excitation coil via an electrical connection.

6. The multifunctional multi-laser directional energy deposition system according to claim 5, characterized in that, The auxiliary ultrasonic field application device includes an ultrasonic generator, a transducer, and an amplitude transformer; the ultrasonic generator is electrically connected to the transducer, and the transducer is connected to the amplitude transformer; the transducer and the amplitude transformer are mounted on the end of a six-degree-of-freedom robotic arm via a bracket and are located near the coaxial dual-laser cladding head, with the ultrasonic end of the amplitude transformer facing the deposition area.

7. The multifunctional multi-laser directional energy deposition system according to claim 1, characterized in that, The online monitoring module includes a coaxial CCD camera, an off-axis camera, and a microphone. The coaxial CCD camera is located inside the coaxial dual-laser cladding head and couples the laser beam with the camera's visual optical path through a beam splitter for direct observation of the frontal morphology image of the molten pool. The off-axis camera is positioned near the coaxial dual-laser cladding head using a fixture to observe the dynamic changes in the deposition trajectory and the molten pool. The microphone is positioned near the coaxial dual-laser cladding head using a fixture to collect the acoustic signals generated by the interaction between the laser and the material. The coaxial CCD camera, off-axis camera, and microphone are connected to the data processing unit of the integrated control module to achieve real-time analysis and quality control of the online detection data.

8. A multifunctional multi-laser directional energy deposition system according to claim 1, characterized in that, The integrated control module includes an industrial computer, a path planning module, a motion controller, an I / O control card, a data processing unit, and an industrial Ethernet communication module.

9. A control method for a multifunctional multi-laser directional energy deposition system comprising any one of claims 1-8, characterized in that, Includes the following steps: S1. Obtain a 3D model of the component to be manufactured, and generate an eight-axis linkage printing path based on the 3D model, in which a six-degree-of-freedom robotic arm and a dual-axis rotary table move in coordination; select a single output mode of infrared laser, green laser, or blue laser, or a composite output mode of any two lasers, according to the material to be deposited and the process requirements, and set the laser process parameters, magnetic field working parameters, and / or ultrasonic field working parameters; the integrated control module generates control timing instructions for laser output, material delivery, multi-physics field assistance, and online monitoring based on the eight-axis linkage printing path and the set working parameters; S2. Control the eight-axis linkage motion platform to move to a safe position, and detect whether the eight-axis linkage motion platform, the multi-source laser module, the multi-material conveying module, the multi-physics field auxiliary module, and the online monitoring module are in normal working condition; after the detection is normal, turn on the protective gas, and control the eight-axis linkage motion platform to move to the deposition start pose; S3. Perform deposition according to the eight-axis linkage printing path, control the six-degree-of-freedom robotic arm and the dual-axis rotary table to move in coordination, and start the online monitoring module according to the control timing instructions, turn on the laser output and powder or filament feeding, and start the auxiliary magnetic field application device and / or auxiliary ultrasonic field application device; the auxiliary magnetic field application device and the auxiliary ultrasonic field application device move synchronously with the coaxial dual laser cladding head, so that the magnetic field action area and the ultrasonic field action area move synchronously with the laser action area and continuously correspond to the current molten pool; S4. During the deposition process, the online monitoring module collects real-time image information of the molten pool and process acoustic signals. The data processing unit analyzes the current deposition state based on the collected information. The integrated control module dynamically adjusts at least one of the following based on the analysis results: laser output mode, laser power, powder feeding rate, wire feeding speed, magnetic field working parameters, and / or ultrasonic field working parameters. When adjusting the moving speed of the eight-axis linkage motion platform, the motion timing of subsequent path segments and the control timing of each functional module are updated synchronously. S5. When the end of single-layer deposition, path switching, or pause condition is detected, the integrated control module executes the laser shutdown, powder feeding stop, wire feeding retraction, multiphysics field shutdown, online monitoring stop, motion platform repositioning, and protective gas delay shutdown according to the control timing instructions; when an abnormal state is detected, an alarm shutdown operation is executed. S6. When there is a subsequent deposition task, control the eight-axis linkage motion platform to move to the next deposition starting pose and repeat steps S3 to S5; when there is no subsequent deposition task, end the deposition process.

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