Laser-arc hybrid additive manufacturing system based on trajectory-power dynamic regulation and working method thereof

Abstract

The application discloses a laser electric arc hybrid additive manufacturing system based on trajectory-power dynamic regulation and a working method thereof. The system comprises a laser unit, a beam shaping unit, a deformation optical unit, an electric arc unit, a first wire feeding unit, a second wire feeding unit, a substrate unit, a robot unit, a monitoring and control unit, a laser swing mode unit and a laser power modulation curve unit. The laser energy distribution and wavefront are dynamically modulated through the beam shaping and deformation optical unit, and the laser scanning trajectory and the laser power are cooperatively controlled to construct controllable energy distribution and temperature gradient within the dot matrix unit scale. Meanwhile, an electric arc heat source is introduced as an auxiliary heat input to form a complementary hybrid heat source with the laser to stabilize the molten pool shape and prolong the effective existence time. The system also realizes controllable deposition of single material, multi-material or gradient material dot matrix structure through independent control of the double wire feeding units. The corresponding working method realizes stable forming of the dot matrix structure through point-by-point and layer-by-layer trajectory-power cooperative regulation. The application can effectively improve the consistency, stability and metallurgical quality of the dot matrix structure forming, and is suitable for manufacturing of lightweight, high-performance and complex dot matrix structure parts.

Description

Technical Field

[0001] This invention belongs to the field of additive manufacturing technology, and in particular relates to a laser-arc composite additive manufacturing system based on trajectory-power dynamic control and its working method. Background Technology

[0002] Additive manufacturing (AM) is an advanced manufacturing technology based on layer-by-layer material deposition, enabling the efficient forming of complex structures. It has been widely used in aerospace, energy equipment, and biomedicine. Among these technologies, laser additive manufacturing uses a laser beam as the main energy source to melt metal materials and deposit them layer by layer to manufacture parts. It is currently one of the more mature additive manufacturing technologies.

[0003] With the increasing demand for lightweight and high-performance structures, lattice structures, due to their advantages such as high specific strength and high specific stiffness, have gradually become an important research direction in the field of additive manufacturing. However, lattice structures are characterized by small unit size, short forming pitch, and sensitivity to heat accumulation, which places higher demands on energy input methods and molten pool stability. Existing laser additive manufacturing technologies mostly use fixed power and continuous scanning trajectories, which are difficult to adapt to the discrete, point-by-point forming process characteristics of lattice structures. This can easily cause thermal interference between adjacent units, resulting in insufficient consistency and stability in lattice forming. In traditional laser additive manufacturing, the laser beam typically exhibits a Gaussian energy distribution, with energy highly concentrated at the center of the spot and rapidly attenuating at the edges. During the forming process of lattice structures, this energy distribution characteristic can easily cause local overheating and element burn-off, while also potentially leading to insufficient melting in the edge regions. This makes it difficult to precisely control the molten pool temperature field and temperature gradient, thereby causing molten pool fluctuations, spatter, and forming defects.

[0004] To improve energy input characteristics, existing technologies have proposed additive manufacturing solutions such as laser beam shaping, power modulation, and laser-arc composite heat sources. However, these solutions primarily focus on overall heat input regulation, lacking precise control over the synergistic relationship between laser scanning trajectory and power. Furthermore, the temporal and spatial coupling and controllability of the laser and arc heat source are limited, making it difficult to construct stable and controllable energy distribution and temperature gradients within the lattice unit scale. Molten pool behavior remains prone to fluctuations, and the forming quality and consistency of the lattice structure are difficult to guarantee. Therefore, how to achieve dynamic synergistic control of laser scanning trajectory and power during the additive manufacturing process of lattice structures, and effectively complement the arc heat source to precisely regulate the molten pool energy distribution and temperature gradient, is a key problem that urgently needs to be solved in existing technologies. Summary of the Invention

[0005] The purpose of this invention is to provide a laser-arc composite additive manufacturing system and its working method based on trajectory-power dynamic control, in order to solve the problems of difficult precise control of energy input distribution, independent laser scanning trajectory and power control, insufficient synergy between laser and arc heat source, and poor stability and forming consistency of molten pool at the lattice unit scale in the existing lattice structure additive manufacturing process. It realizes the controllable adjustment of energy distribution and temperature gradient within the unit scale of the lattice structure, thereby improving the forming accuracy, manufacturing efficiency and process stability of the lattice structure, so as to meet the manufacturing needs of lightweight, high-performance and complex lattice structure parts in aerospace, mechanical manufacturing and other fields.

[0006] The technical solution to achieve the purpose of this invention is as follows:

[0007] A laser-arc composite additive manufacturing system based on trajectory-power dynamic control includes, in sequence, a laser unit, a beam shaping unit, a deformable optics unit, an arc unit, a first wire feeding unit, a second wire feeding unit, a substrate unit, a robot unit, and a monitoring and control unit.

[0008] The laser unit is used to generate a laser beam with a set power, wavelength and modulation capability, as the main energy source in the lattice structure additive manufacturing process;

[0009] The beam shaping unit is used to adjust the spatial distribution and shape of the original laser beam output by the laser unit in order to change the shape, size and energy density distribution of the laser spot.

[0010] The deformable optical unit is used to dynamically modulate the laser beam after it has been processed by the beam shaping unit, and adjust the wavefront shape and propagation direction of the laser beam in real time, thereby realizing active control of the temperature gradient of the lattice molten pool.

[0011] The electric arc unit is used to generate an electric arc heat source and work in conjunction with the laser beam on the lattice molten pool region to supplement the heat input and regulate the flow state and stability of the molten pool.

[0012] The first wire feeding unit is used to feed the first filler material wire into the laser-arc composite action region;

[0013] The second wire feeding unit is used to deliver a second filler material wire to the laser-arc composite action region to achieve the deposition of a single material or multi-material lattice structure;

[0014] The substrate unit is used to support the layer-by-layer deposition of the lattice structure and serves as a component of the electrical circuit of the arc unit.

[0015] The robot unit is used to carry and drive the laser unit and its related optical components to realize the spatial motion scanning of the laser beam relative to the substrate unit.

[0016] The monitoring and control unit is used to acquire operating parameters and status information during the lattice structure forming process, and to coordinate and control the beam shaping unit, deformable optics unit, arc unit, first wire feeding unit, and second wire feeding unit based on preset lattice structure forming parameters. Specifically, through dynamic coordinated control of the laser scanning trajectory and laser power, a controllable energy distribution and temperature gradient are constructed within the lattice unit scale, achieving stable lattice structure forming.

[0017] The laser oscillation mode unit is used to monitor and provide feedback on the oscillation mode information of the laser beam in real time.

[0018] The laser power modulation curve unit is used to monitor and provide feedback on the laser power change information of the laser beam in real time.

[0019] The beam shaping unit is used to modulate the original laser beam output by the laser unit into a non-axisymmetric or quasi-flat-top energy distribution spot suitable for discrete forming of lattice units, thereby limiting the spatial expansion of laser energy within the scale of a single lattice unit. The deformable optics unit is used to dynamically modulate the wavefront shape and energy distribution of the laser beam in real time during the lattice unit forming process, so that the laser forms a directionally controllable energy gradient inside the lattice unit, thereby inducing directional surface tension gradient-driven flow within the lattice molten pool to suppress asymmetric collapse or flow of molten metal during the lattice forming process. The arc unit is used to provide auxiliary heat input around the lattice molten pool formed by the laser, and its arc action area is spatially above the main laser heating area. By dividing the lattice into overlapping or adjacent units, the effective existence time of the lattice molten pool is extended by reducing the temperature gradient amplitude in the area surrounding the lattice molten pool, thereby improving the forming integrity and repeatability of the lattice units. The first and second wire feeding units respectively feed filler material wires to the lattice molten pool, and by independently adjusting the wire feeding speed and timing of the two wire feeding units, the filler material completes controlled melting and deposition within a single lattice unit. The monitoring and control unit is used to acquire laser energy distribution, molten pool size, and forming stability parameters in real time based on the lattice unit scale, and accordingly coordinates the laser power, spot shape, arc heat input, and wire feeding parameters to ensure the geometric consistency and metallurgical bonding quality between each lattice unit.

[0020] The deformable optical unit employs adaptive optical elements based on electromagnetic actuation or piezoelectric actuation. By controlling multiple independent driving units, the deformation of the reflector or transmission optical element is adjusted to achieve shape reconstruction and energy distribution control of the laser spot within the lattice unit scale.

[0021] The arc unit is an independently controllable arc generating device. Its arc current, voltage, and spatial position are dynamically adjusted according to the geometric dimensions of the lattice structure, the lattice spacing, and the forming requirements. The arc heat source and the laser beam work together at a set angle to act on the lattice molten pool area to enhance the stability of the lattice molten pool and improve the material filling and fusion quality.

[0022] The first wire feeding unit and the second wire feeding unit are independently controlled wire feeding units, which respectively feed filler material wires of different compositions or different diameters. By adjusting the ratio of the wire feeding speeds of the two wire feeding units, the composition control or gradient material deposition of different lattice units or different layers in the lattice structure can be achieved.

[0023] The first wire feeding unit and the second wire feeding unit feed wire into the lattice molten pool at a preset angle. The angle between the wire feeding direction and the laser beam axis is 30°–60°, so as to improve the capture efficiency and deposition stability of the material in the lattice molten pool.

[0024] On the other hand, the present invention also provides a method for operating a laser-arc composite additive manufacturing system based on trajectory-power dynamic control, comprising the following steps:

[0025] Step 1: Based on the preset geometric parameters and forming sequence of the dot matrix structure, determine the spatial position, laser scanning trajectory, laser power waveform, and arc heat input parameters of a single dot matrix unit, and input the parameters into the monitoring and control unit;

[0026] Step 2: Start the laser unit. The laser beam passes through the beam shaping unit and the deformable optics unit (3) in sequence, forming a laser energy distribution of a preset shape within the lattice unit scale. This allows the laser to build a temperature gradient with controllable direction inside the lattice unit, which is used to adjust the initial shape of the lattice molten pool.

[0027] Step 3: While the laser forms the lattice molten pool, the electric arc unit is activated so that the electric arc heat source acts on the periphery or adjacent area of ​​the lattice molten pool. By adjusting the electric arc current and voltage, the heat loss around the lattice molten pool is compensated, the effective existence time of the lattice molten pool is extended, and its shape is stabilized.

[0028] Step 4: Based on the forming requirements of the lattice unit, start the first wire feeding unit and the second wire feeding unit, and deliver the filler material to the lattice molten pool according to the preset wire feeding sequence and wire feeding speed, so that the filler material completes controlled melting and deposition within the scale of a single lattice unit.

[0029] Step 5: After the deposition of a single lattice unit is completed, pause the laser beam, the electric arc heat source and the wire feeding process, and set a predetermined cooling or waiting interval to allow the formed lattice unit to enter a stable solidification state.

[0030] Step 6: Control the robot unit to drive the laser unit and its optical components to move to the next lattice unit position, and repeat steps 2 to 5 until the lattice structure is completed point by point and layer by layer.

[0031] Compared with the prior art, the significant progress of the present invention is as follows: (1) The present invention is based on a laser-arc composite heat source with dynamic coordinated control of trajectory and power, which gives full play to the complementary advantages of high energy density of laser and stable heat input of arc. Through the combined heating effect of laser beam and arc heat source, precise energy distribution is achieved within the scale of lattice unit, which effectively improves the stability and filling efficiency of molten pool. Laser beam is used to achieve high-precision and programmable energy input and temperature gradient control, and arc heat source is used to supplement heat input and stabilize molten pool flow, avoiding the problems of large molten pool fluctuation and uneven energy distribution in traditional additive manufacturing. (2) The present invention achieves rapid and precise control of laser energy distribution through the synergistic effect of beam shaping unit and deformable optics unit. Combined with the dynamic matching of laser scanning trajectory and power, a controllable energy distribution and temperature gradient field are constructed in the lattice structure forming process, which effectively reduces the temperature gradient of heat-affected zone, suppresses defects such as material overheating, burn-off and coarsening, and significantly improves the forming quality and consistency of lattice structure. (3) This invention, through precise coordinated control of laser parameters, arc parameters, and wire feeding parameters, possesses excellent process adaptability and can flexibly meet the manufacturing needs of single-material, multi-material, and gradient material lattice structures. By selecting different combinations of welding wires and precisely adjusting the wire feeding ratio, a smooth transition of material composition in different regions of the lattice structure is achieved, improving the compositional uniformity and overall performance of the deposited layer, and avoiding the problems of abrupt changes in material composition and uneven performance in traditional additive manufacturing.

[0032] To more clearly illustrate the functional characteristics and structural parameters of the present invention, further explanation is provided below in conjunction with the accompanying drawings and specific embodiments. Attached Figure Description

[0033] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0034] Figure 1 This is a system schematic diagram of the present invention;

[0035] Figure 2 The light spots of different oscillation modes obtained by the light beam of the present invention after passing through the beam shaping unit and the deformable optical unit.

[0036] Figure 3 This is a power schematic diagram showing different curves obtained by power modulation of the laser of the present invention.

[0037] The figures are labeled as follows: 1-Laser unit, 2-Beam shaping unit, 3-Deformation optics unit, 4-Arc unit, 5-First wire feeding unit, 6-Second wire feeding unit, 7-Substrate unit, 8-Robot unit, 9-Monitoring and control unit, 10-Laser oscillation mode unit, 11-Laser power modulation curve unit Detailed Implementation

[0038] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0039] This invention provides a laser-arc composite additive manufacturing system based on trajectory-power dynamic control, combined with... Figures 1-3 It includes, in sequence, a laser unit 1, a beam shaping unit 2, a deformable optics unit 3, an arc unit 4, a first wire feeding unit 5, a second wire feeding unit 6, a substrate unit 7, a robot unit 8, a monitoring and control unit 9, a laser oscillation mode unit 10, and a laser power modulation curve unit 11.

[0040] The laser unit 1 is used to generate a laser beam with set power, wavelength and modulation capability, which serves as the main energy source in the additive manufacturing process of the lattice structure, so as to achieve precise control of the energy input position and intensity within the lattice unit scale.

[0041] The beam shaping unit 2 is used to adjust the spatial distribution and shape of the original laser beam output by the laser unit 1, so as to change the shape, size and energy density distribution of the laser spot, thereby matching the laser energy with the geometric characteristics of the lattice unit and reducing energy spillover.

[0042] The deformable optical unit 3 is used to dynamically modulate the laser beam after it has been processed by the beam shaping unit 2, and adjust the wavefront shape and propagation direction of the laser beam in real time, thereby constructing a controllable temperature gradient field within the lattice unit scale and realizing active regulation of the flow behavior of the lattice molten pool.

[0043] The electric arc unit 4 is used to generate an electric arc heat source and work in conjunction with the laser beam on the lattice molten pool region to supplement the heat input and regulate the flow state and stability of the molten pool, thereby reducing thermal fluctuations and the tendency of the molten pool to collapse during the lattice forming process.

[0044] The first wire feeding unit 5 is used to deliver the first filling material wire to the laser-arc composite action area to realize material replenishment within the lattice unit;

[0045] The second wire feeding unit 6 is used to deliver the second filler material wire to the laser-arc composite action area to achieve the deposition of a single material or multi-material lattice structure and to provide a material basis for composition control.

[0046] The substrate unit 7 is used to support the layer-by-layer deposition of the lattice structure and serves as a component of the electrical circuit of the arc unit 4 to ensure stable arc combustion.

[0047] The robot unit 8 is used to carry and drive the laser unit 1 and its related optical components to realize the spatial motion scanning of the laser beam relative to the substrate unit 7, so as to ensure the accuracy of the dot matrix unit position arrangement.

[0048] The monitoring and control unit 9 is used to acquire the operating parameters and status information during the formation process of the lattice structure, and to coordinate and control the beam shaping unit 2, the deformable optical unit 3, the arc unit 4, the first wire feeding unit 5, and the second wire feeding unit 6 based on the preset lattice structure forming parameters. In this process, through the dynamic coordinated regulation of the laser scanning trajectory and the laser power, a controllable energy distribution and temperature gradient are constructed within the lattice unit scale, thereby achieving stable and repeatable forming of the lattice structure.

[0049] The laser oscillation mode unit 10 is used to monitor and provide feedback on the oscillation mode information of the laser beam in real time.

[0050] The laser power modulation curve unit 11 is used to monitor and provide feedback on the laser power change information of the laser beam in real time.

[0051] The beam shaping unit 2 is used to modulate the original laser beam output by the laser unit 1 into a non-axisymmetric or quasi-flat-top energy distribution spot suitable for discrete forming of lattice units, thereby limiting the spatial expansion of laser energy within a single lattice unit scale and reducing thermal interference between adjacent lattice units. The deformable optics unit 3 is used to dynamically modulate the wavefront shape and energy distribution of the laser beam in real time during the lattice unit forming process, so that the laser forms a directionally controllable energy gradient inside the lattice unit, thereby inducing directional surface tension gradient-driven flow within the lattice molten pool to suppress asymmetric collapse or flow of molten metal during the lattice forming process. The arc unit 4 is used to provide auxiliary heat input around the lattice molten pool formed by the laser, and its arc action area is adjacent to the laser. The main heating zones partially overlap or are adjacent to each other in space. By reducing the temperature gradient amplitude around the lattice molten pool, the effective existence time of the lattice molten pool is extended, thereby improving the forming integrity and repeatability of the lattice units. The first wire feeding unit 5 and the second wire feeding unit 6 respectively feed the filler material wire to the lattice molten pool. By independently adjusting the wire feeding speed and timing of the two wire feeding units, the filler material completes controlled melting and deposition within a single lattice unit. The monitoring and control unit 9 is used to acquire laser energy distribution, molten pool size, and forming stability parameters in real time based on the lattice unit scale. Based on this, the laser power, spot shape, arc heat input, and wire feeding parameters are coordinated to ensure the geometric consistency and metallurgical bonding quality between each lattice unit.

[0052] The deformable optical unit 3 adopts an adaptive optical element based on electromagnetic actuation or piezoelectric actuation. By controlling multiple independent driving units to adjust the deformation of the reflector or transmission optical element, the shape reconstruction and energy distribution control of the laser spot within the lattice unit scale are realized, thereby improving the response speed and accuracy of laser control during the lattice forming process.

[0053] The arc unit 4 is an independently controllable arc generating device. Its arc current, voltage and spatial position are dynamically adjusted according to the geometric dimensions of the lattice structure, the lattice spacing and the forming requirements. The arc heat source and the laser beam work together at a set angle to act on the lattice molten pool area to enhance the thermal stability of the lattice molten pool and improve the material filling and fusion quality.

[0054] The first wire feeding unit 5 and the second wire feeding unit 6 are independently controlled wire feeding units, which respectively transport filler material wires of different compositions or different diameters. By adjusting the ratio of the wire feeding speeds of the two wire feeding units, the composition control or gradient material deposition of different lattice units or different layers in the lattice structure can be achieved.

[0055] The first wire feeding unit 5 and the second wire feeding unit 6 feed wires into the lattice molten pool at a preset angle. The angle between the wire feeding direction and the laser beam axis is 30°–60°, so as to improve the capture efficiency of the filler material entering the molten pool, reduce splashing, and improve the stability of the lattice deposition process.

[0056] The present invention discloses a working method for a laser-arc composite additive manufacturing system based on trajectory-power dynamic control, comprising the following steps:

[0057] Step 1: Based on the preset geometric parameters and forming sequence of the dot matrix structure, determine the spatial position, laser scanning trajectory, laser power waveform, and arc heat input parameters of a single dot matrix unit, and input the parameters into the monitoring and control unit 9;

[0058] Step 2: Start laser unit 1. The laser beam passes through beam shaping unit 2 and deformable optics unit 3 in sequence, forming a laser energy distribution of a preset shape within the lattice unit scale. This allows the laser to build a directionally controllable temperature gradient inside the lattice unit to adjust the initial shape of the lattice molten pool.

[0059] Step 3: While the laser forms the lattice molten pool, the electric arc unit 4 is activated so that the electric arc heat source acts on the periphery or adjacent area of ​​the lattice molten pool. By adjusting the electric arc current and voltage, the heat loss around the lattice molten pool is compensated, the effective existence time of the lattice molten pool is extended, and its shape is stabilized.

[0060] Step 4: According to the forming requirements of the lattice unit, start the first wire feeding unit 5 and the second wire feeding unit 6, and deliver the filler material to the lattice molten pool according to the preset wire feeding sequence and wire feeding speed, so that the filler material completes controlled melting and deposition within the scale of a single lattice unit.

[0061] Step 5: After the deposition of a single lattice unit is completed, pause the laser beam, the electric arc heat source and the wire feeding process, and set a predetermined cooling or waiting interval to allow the formed lattice unit to enter a stable solidification state.

[0062] Step 6: Control robot unit 8 to drive laser unit 1 and its optical components to move to the next lattice unit position, repeat steps 2 to 5 until the lattice structure is completed point by point and layer by layer.

[0063] This invention dynamically modulates the laser energy distribution and wavefront through beam shaping and deformation optics units, and coordinates the laser scanning trajectory and laser power to construct a controllable energy distribution and temperature gradient within the lattice unit scale. Simultaneously, an electric arc heat source is introduced as an auxiliary heat input, forming a complementary composite heat source with the laser to stabilize the molten pool morphology and extend its effective existence time. The system also achieves controllable deposition of single-material, multi-material, or gradient-material lattice structures through independent control of dual wire-feeding units. The corresponding working method achieves stable lattice structure formation through point-by-point and layer-by-layer trajectory-power coordinated regulation. Compared with existing technologies, this invention effectively improves the consistency, stability, and metallurgical quality of lattice structure formation, and is suitable for manufacturing lightweight, high-performance, and complex lattice structure components.

[0064] Example

[0065] Example 1

[0066] First, the substrate unit 7 is pretreated by cleaning its surface with anhydrous ethanol to remove oil and impurities. After cleaning, the substrate unit 7 is fixed on the worktable using a fixture to ensure its stability and prevent displacement during the lattice structure additive manufacturing process.

[0067] The output power of laser unit 1 is set to 3000W. Laser unit 1 emits a laser beam with a Gaussian energy distribution, which enters beam shaping unit 2. Beam shaping unit 2 processes the laser beam using a collimating beam shaper, shaping the Gaussian laser beam into a quasi-flat-top beam with a uniform energy distribution to improve laser energy utilization and reduce the central energy peak. Simultaneously, the defocusing amount is adjusted so that the laser beam focal point is located +10mm above the surface of substrate unit 7, and the laser scanning speed is set to 12mm / s.

[0068] The quasi-flat-top beam, processed by beam shaping unit 2, enters deformable optics unit 3. By controlling multiple electromagnetic drive units within deformable optics unit 3, the reflector undergoes controllable deformation, thereby generating a non-axisymmetric spot shape within the lattice unit scale. After further adjustment by the focusing unit, a laser spot with directional energy distribution is formed on the surface of substrate unit 7, such as... Figure 2 As shown, a controllable temperature gradient is constructed within a single lattice unit.

[0069] Based on the preset geometric parameters of the dot matrix structure, the spatial distribution and forming sequence of the dot matrix units are set in the monitoring and control unit 9, and a corresponding laser scanning trajectory and laser power waveform are configured for each dot matrix unit. During the dot matrix unit forming process, the laser beam performs short-range scanning within the dot matrix unit range according to the preset trajectory, while the laser power is dynamically adjusted according to the scanning position, thereby achieving coordinated control of trajectory and power within the scale of the dot matrix unit.

[0070] Adjust the wire feeding angle of the first wire feeding unit 5 so that the angle between the welding wire and the laser beam axis is 45°, and adjust the end of the welding wire to be close to the surface of the substrate unit 7 so that it is located in the laser spot action area, and keep the distance between the end of the welding wire and the surface of the substrate unit 7 at 1.5mm.

[0071] Turn on arc unit 4, set the arc current to 100A and the arc voltage to 15V, so that the arc heat source acts on the periphery of the lattice molten pool, which is spatially adjacent to the main laser heating area. Simultaneously start the side-blowing protective gas device to introduce pure argon protective gas into the processing area, with the gas flow rate set to 25L / min, to prevent oxidation of the molten pool during the forming process.

[0072] The first layer of lattice units is deposited. After the first layer of lattice units is formed, its height is measured and set as the interlayer offset for subsequent layer-by-layer lattice deposition. Then, according to the preset lattice unit positions and interlayer offsets, the lattice structure is additively manufactured point by point and layer by layer. After each layer is formed, the lattice unit is allowed to cool to below 40°C before the next layer of lattice units is deposited, until the entire lattice structure is completed.

[0073] Example 2

[0074] First, the substrate unit 7 is pre-processed and fixed on the worktable. The output power of the laser unit 1 is set to 3000W. The laser beam is shaped into a quasi-flat-top beam by the beam shaping unit 2, and the laser focal point is located 10mm above the surface of the substrate unit 7 by adjusting the defocusing amount. The laser scanning speed is set to 12mm / s.

[0075] The laser beam wavefront is dynamically modulated by the deformable optics unit 3 to generate a light spot morphology with a directional gradient distribution within the lattice unit scale. The monitoring and control unit 9 sets different laser scanning trajectories and power waveforms for different lattice units according to their positions and forming sequences, thereby achieving dynamic and coordinated control of trajectory and power within the lattice unit scale.

[0076] Unlike Embodiment 1, in this embodiment, the first wire feeding unit 5 is configured with pure aluminum welding wire, and the second wire feeding unit 6 is configured with pure titanium welding wire. The wire feeding angles of the two wire feeding units are adjusted so that both welding wires are fed into the lattice molten pool area at a 45° angle, and the distance between the end of the welding wire and the surface of the substrate unit 7 is maintained at 1.5 mm. According to the material composition requirements of the target lattice unit, the wire feeding speeds of the first wire feeding unit 5 and the second wire feeding unit 6 are set in the monitoring and control unit 9, respectively.

[0077] Arc unit 4 is activated, with the arc current set to 100A and the arc voltage to 15V. This allows the arc heat source to provide auxiliary heat input around the lattice molten pool, slowing down the cooling rate of the molten pool and improving the stability of multi-material fusion. Simultaneously, pure argon protective gas is introduced into the processing area at a flow rate of 25L / min.

[0078] In the lattice structure additive manufacturing process, the material composition control of different lattice units or different layers is achieved by dynamically adjusting the wire feeding speed ratio of the first wire feeding unit 5 and the second wire feeding unit 6: when the wire feeding speeds of the two wire feeding units are equal, Ti-Al alloy lattice units with approximately equal atomic ratios are obtained; when the wire feeding speed of the first wire feeding unit 5 is higher than that of the second wire feeding unit 6, the aluminum content in the lattice unit increases; when the wire feeding speed of the second wire feeding unit 6 is higher than that of the first wire feeding unit 5, the titanium content in the lattice unit increases.

[0079] After each lattice unit is formed, a cooling waiting time is set to allow it to solidify fully. Then, the robot unit 8 drives the laser unit 1 to move to the next lattice unit position. The above process is repeated to finally obtain a multi-material lattice structure with adjustable spatial composition.

[0080] Matters not covered in this invention are common knowledge. The above embodiments are only for illustrating the technical concept and features of this invention, and are intended to enable those skilled in the art to understand the content of this invention and implement it accordingly. They should not be construed as limiting the scope of protection of this invention. All equivalent changes or modifications made in accordance with the spirit and essence of this invention should be covered within the scope of protection of this invention.

Claims

1. A laser-arc composite additive manufacturing system based on trajectory-power dynamic control, comprising a laser unit (1), a beam shaping unit (2), a deformation optics unit (3), an arc unit (4), a first wire feeding unit (5), a second wire feeding unit (6), and a substrate unit (7) arranged sequentially, characterized in that, It also includes a robot unit (8), a monitoring and control unit (9), a laser oscillation mode unit (10), and a laser power modulation curve unit (11); among which, The robot unit (8) is used to carry and drive the laser unit (1) and its related optical components to realize the spatial motion scanning of the laser beam relative to the substrate unit (7); The monitoring and control unit (9) is used to acquire the operating parameters and status information during the formation process of the lattice structure, and to coordinate and control the beam shaping unit (2), the deformable optical unit (3), the arc unit (4), the first wire feeding unit (5), and the second wire feeding unit (6) based on the preset lattice structure forming parameters. In this way, through the dynamic coordinated regulation of the laser scanning trajectory and the laser power, a controllable energy distribution and temperature gradient are constructed within the lattice unit scale to achieve stable formation of the lattice structure. The laser oscillation mode unit (10) is used to monitor and provide feedback on the oscillation mode information of the laser beam in real time. The laser power modulation curve unit (11) is used to monitor and provide feedback on the laser power change information of the laser beam in real time.

2. The laser-arc composite additive manufacturing system based on trajectory-power dynamic control according to claim 1, characterized in that, The beam shaping unit (2) modulates the original laser beam output by the laser unit (1) into a non-axisymmetric or quasi-flat-top energy distribution spot suitable for discrete forming of the lattice unit, so as to limit the spatial expansion of laser energy within the scale of a single lattice unit.

3. The laser-arc composite additive manufacturing system based on trajectory-power dynamic control according to claim 1, characterized in that, The deformable optical unit (3) dynamically modulates the wavefront shape and energy distribution of the laser beam in real time during the formation of the lattice unit, so that the laser forms a directionally controllable energy gradient inside the lattice unit, thereby inducing a directional surface tension gradient to drive the flow in the lattice molten pool and suppressing the asymmetric collapse or flow of molten metal during the lattice formation process.

4. The laser-arc composite additive manufacturing system based on trajectory-power dynamic control according to claim 1, characterized in that, The electric arc unit (4) provides auxiliary heat input around the lattice molten pool formed by the laser. Its arc action area partially overlaps or is adjacent to the main laser heating area in space. By reducing the temperature gradient amplitude around the lattice molten pool, the effective existence time of the lattice molten pool is extended, thereby improving the forming integrity and repeatability of the lattice unit.

5. The laser-arc composite additive manufacturing system based on trajectory-power dynamic control according to claim 2, characterized in that, The first wire feeding unit (5) and the second wire feeding unit (6) feed wire to the lattice molten pool at a preset angle, and the angle between the wire feeding direction and the laser beam axis is 30°-60°.

6. A method of operating the laser-arc composite additive manufacturing system according to any one of claims 1-5, characterized in that, Includes the following steps: Step 1: Based on the preset geometric parameters of the dot matrix structure and the forming sequence, determine the spatial position, laser scanning trajectory, laser power waveform and arc heat input parameters of a single dot matrix unit, and input the parameters into the monitoring and control unit (9). Step 2: Start the laser unit (1). The laser beam passes through the beam shaping unit (2) and the deformable optics unit (3) in sequence, forming a laser energy distribution of a preset shape within the lattice unit scale. This allows the laser to build a temperature gradient with controllable direction inside the lattice unit, which is used to adjust the initial shape of the lattice molten pool. Step 3: While the laser forms the lattice molten pool, the electric arc unit (4) is activated so that the electric arc heat source acts on the periphery or adjacent area of ​​the lattice molten pool. By adjusting the electric arc current and voltage, the heat loss around the lattice molten pool is compensated, the effective existence time of the lattice molten pool is extended, and its shape is stabilized. Step 4: According to the forming requirements of the lattice unit, start the first wire feeding unit (5) and the second wire feeding unit (6) to deliver the filling material to the lattice molten pool according to the preset wire feeding sequence and wire feeding speed, so that the filling material completes controlled melting and deposition within the scale of a single lattice unit. Step 5: After the deposition of a single lattice unit is completed, pause the laser beam, the electric arc heat source and the wire feeding process, and set a predetermined cooling or waiting interval to allow the formed lattice unit to enter a stable solidification state. Step 6: Control the robot unit (8) to drive the laser unit (1) and its optical components to move to the next lattice unit position, repeat steps 2 to 5 until the lattice structure is completed point by point and layer by layer.

Images