An arrayed laser additive manufacturing method and apparatus

Abstract

The application belongs to the technical field of laser additive manufacturing, and particularly relates to an array type laser additive manufacturing method and device, which comprises the following steps: S1, digital model import and layering slicing; S2, scanning path planning and filling setting; S3, array type laser synchronous output control; S4, powder flow and powder feeding path control; S5, according to the width of the additive, the width of single track cladding is adjusted in real time; S6, according to the slice layer material of the additive, the matching material is delivered; S7, S1-S6 are repeated, and layer-by-layer accumulation is performed until the part manufacturing is completed. The application can accurately control the grain size, improve the material microstructure, and improve the mechanical properties; the generation of defects such as thermal cracks and pores is reduced, the stability of the deposition process is ensured; the interlayer bonding is optimized, the quality of multi-layer deposition is ensured; the residual stress is reduced, the size precision, shape stability and fatigue performance of the part are improved; the post-processing requirement is reduced, and the processing cost is reduced.

Description

Technical Field

[0001] This invention belongs to the field of laser additive manufacturing technology, and particularly relates to an array-type laser additive manufacturing method and apparatus. Background Technology

[0002] Laser additive manufacturing technology, particularly laser deposition manufacturing, is an advanced directional energy deposition technology that uses a high-energy laser beam to melt synchronously fed metal powder or filament, depositing it layer by layer onto a substrate to ultimately form a three-dimensional solid part. Due to its advantages such as moldlessness and high design freedom, this technology shows great potential in the manufacturing and repair of complex parts in aerospace, automotive, and energy fields.

[0003] However, existing laser deposition manufacturing technology mainly relies on the coordinated operation of a single laser beam and a single powder feeding nozzle, which presents several technical bottlenecks in practical applications. Firstly, regarding forming accuracy, the molten pool width formed by a single laser beam is limited and fixed. When processing wide areas, multiple overlapping passes are required, easily leading to inter-pass depressions or protrusions, resulting in poor surface flatness and difficulty in precisely controlling dimensional accuracy. Secondly, regarding the stability of the forming process, concentrated heating from a single energy source easily causes violent fluctuations in the molten pool, triggering severe particle spatter. This not only degrades the surface quality of the workpiece, but spatter adhering to optical lenses or the inside of equipment also poses quality hazards and safety risks. Thirdly, regarding the control of the material solidification process, high heat input at a single point and rapid cooling create a large temperature gradient, making the solidification process difficult to control. This easily leads to the formation of coarse columnar crystals, pores, and incomplete fusion within the deposited layer, accumulating significant residual stress, causing part deformation and cracking, severely affecting its mechanical properties and service life.

[0004] Therefore, it is necessary to design an array-type laser additive manufacturing method and apparatus to solve the above problems. Summary of the Invention

[0005] The purpose of this invention is to provide an array-type laser additive manufacturing method and apparatus to solve the technical problems of low forming accuracy, unstable process and uncontrollable solidification process caused by a single laser beam and powder feeding channel.

[0006] To achieve the above objectives, the present invention provides the following solution: an array-type laser additive manufacturing method, comprising the following steps: S1. Importing and Layering the Model: Import the 3D model of the part into the system, slice it into layers along the additive manufacturing direction, and set the thickness of each layer. S2, Scan Path Planning and Filling Settings: Plan the scan path of the array laser for each slice and set the scan parameters; S3, Array-type laser synchronous output control, multiple array-set laser beam output components output synchronously or according to strategy according to the planned scanning path to form a molten pool; S4. Powder flow and powder feeding path control: Multiple arrayed powder feeding components feed metal powder into the molten pool formed in S3, while outputting protective gas through the protective gas path. S5. Based on the width of the additive manufacturing process, control the opening or closing of some of the laser beam output components in multiple arrays to adjust the width of a single cladding layer in real time. S6. Based on the additive manufacturing slice material, the matching material is delivered through multiple array-set powder feeding components; S7. Repeat S1-S6, stacking layer by layer until the part is manufactured.

[0007] According to the array-type laser additive manufacturing method of the present invention, in step S1, the thickness of the slice is 0.3mm-0.8mm.

[0008] According to the present invention, in the array-type laser additive manufacturing method, the scanning parameters in step S2 include scanning spacing and scanning speed. The scanning spacing ranges from 0.1 mm to 1.2 mm, and the scanning speed ranges from 200 mm / min to 1200 mm / min.

[0009] According to the array-type laser additive manufacturing method of the present invention, in step S3, the laser power range of the laser beam output component is 400W-2000W, and the laser spot diameter of the laser beam output component is 0.6mm-2mm.

[0010] According to the array-type laser additive manufacturing method of the present invention, in step S4, the flow rate of the metal powder of the powder feeding component is 5g / min-25g / min, the protective gas output from the protective gas path is an inert gas, the flow rate of the inert gas is 6L / min-15L / min, and the pressure of the inert gas is 0.1Mpa-0.5Mpa.

[0011] According to the array-type laser additive manufacturing method of the present invention, the scanning width in step S5 is adjusted within the range of 1mm-5mm.

[0012] According to the array-type laser additive manufacturing method of the present invention, the process between steps S5 and S6 further includes surface flatness adjustment, solidification adjustment control, and residual stress control.

[0013] According to the array-type laser additive manufacturing method of the present invention, during solidification regulation control, the solidification cooling rate is 10. 3 K / s-10 5When participating in stress control, the laser beam output component is used to irradiate the forming surface with energy. The power of the laser beam output component during energy irradiation is 200W-800W.

[0014] According to the array-type laser additive manufacturing method of the present invention, in step S6, the flow rate of metal powder of a single powder feeding component is 5g / min-25g / min, and the proportion of metal powder of multiple powder feeding components is determined according to the composition design requirements.

[0015] An array-type laser additive manufacturing apparatus for implementing an array-type laser additive manufacturing method includes multiple laser beam output components, multiple powder feeding components, multiple protective gas paths, a water cooling system, a powder conveying system, and optical fibers. The multiple powder feeding components are arranged in an array, the multiple laser beam output components are arranged in an array on both sides of the powder feeding components, the multiple protective gas paths are arranged in an array on both sides of the powder feeding components and located between the powder feeding components and the laser beam output components, the laser beam output components are connected to the optical fibers, the powder feeding components are connected to the powder conveying system, and the water cooling system is correspondingly arranged to the powder conveying system.

[0016] Compared with the prior art, the present invention has the following advantages and technical effects: 1. High forming precision: By controlling the energy and scanning path of each laser beam output component, the thickness and shape of each deposited layer are precisely controlled, thus ensuring extremely high dimensional accuracy during single-pass deposition. The layout of the laser beam output components can be flexibly configured according to processing requirements, avoiding deposition errors caused by excessively large laser spots or uneven heat input, and greatly improving surface quality and geometric accuracy.

[0017] 2. Residual Stress Control: By controlling the energy and scanning path of each laser beam output component, the cooling rate and temperature gradient are effectively adjusted, significantly reducing the generation of residual stress. Smaller heat input prevents excessive thermal gradients during part forming, thus reducing thermal deformation caused by large temperature differences. By rationally adjusting the switching and energy distribution of the laser beam output components, uniform heat input can be maintained during each deposition layer, avoiding stress concentration caused by localized overheating or excessively rapid cooling, thereby preventing internal material inhomogeneity and deformation.

[0018] 3. High forming efficiency: The forming efficiency can be significantly improved by the coordinated work of multiple laser beam output components.

[0019] 4. High Forming Quality: By controlling the power and scanning path of each laser beam output component, precise adjustment of solidification during material deposition can be achieved. Different laser beam output components can be independently controlled, thereby optimizing the temperature distribution in local areas, controlling the cooling rate, achieving a meticulous solidification process, and preventing uneven cooling or thermal cracking. Precise control of the laser beam output component power can affect the grain structure of the material. By adjusting the laser heating and cooling rates, the crystallization process of the material can be controlled, the grain size optimized, and the mechanical properties of the material improved. By adjusting the power of the laser beam output components and the powder feeding component rate, the performance of the deposited material can be controlled. Through localized heating and cooling adjustments in different areas, regional customization of material properties can be achieved. Attached Figure Description

[0020] 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 described 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: Figure 1 This is a schematic diagram of the device structure of the present invention; Figure 2 This is a schematic diagram of multiple laser beams and multiple metal powder flows in the embodiment; Figure 3 This is a schematic diagram illustrating the independent control of the laser beam and metal powder in the embodiment; Figure 4 This is a schematic diagram of the forming area control in the embodiment; Figure 5 This is a schematic diagram for additive manufacturing dimensional control. Figure 6 A schematic diagram of an array of eight laser beams and four metal powders. Figure 7 A schematic diagram of the first control mode of an eight-laser-beam, four-metal-powder array arrangement. Figure 8 A schematic diagram of the second control mode for an eight-laser-beam, four-metal-powder array arrangement. Figure 9 A schematic diagram of the third control mode for an eight-laser-beam, four-metal-powder array arrangement; Figure 10 A schematic diagram of the fourth control mode for an eight-laser-beam, four-metal-powder array arrangement. Figure 11 A schematic diagram of the fifth control mode for an eight-laser-beam, four-metal-powder array arrangement. Figure 12 This is a schematic diagram of simultaneous processing of multi-metal powders; Among them, 1. Laser beam output component; 5. Powder feeding component; 13. Protective gas path; 16. Water cooling system; 18. Powder conveying system; 23. Optical fiber. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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.

[0022] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0023] Reference Figures 1 to 5 As shown, the present invention provides an array-type laser additive manufacturing method, comprising the following steps: S1. Model Import and Layer Slicing: Import the 3D model file of the part (supports STL / STEP / IGES formats), set the additive manufacturing direction, and add necessary support structures. Perform model layer slicing processing, which can be optimized and adjusted according to material type, structural dimensions, and surface quality requirements.

[0024] S2. Scan path planning and fill settings: Based on the part's geometry and process requirements, the scan path is planned, and the array-style scan fill spacing is set and optimized according to material and forming quality requirements. A multi-laser beam array scan trajectory is generated to achieve layer coverage.

[0025] S3, Array-type laser synchronous output control, multiple array-set laser beam output components 1 output synchronously or according to strategy according to the planned scanning path to form a molten pool; S4. Powder flow and powder feeding path control: Multiple arrayed powder feeding components 5 feed metal powder into the molten pool formed in S3, and at the same time output protective gas through protective gas path 13. S5. Based on the width of the additive manufacturing process, control the opening or closing of the middle part of the laser beam output component 1 set in multiple arrays to adjust the width of the single-pass cladding in real time. S6. Based on the additive slicing layer material, the matching material is delivered through multiple arrays of powder feeding components 5; S7. Repeat S1-S6, stacking layer by layer until the part is manufactured.

[0026] Furthermore, in step S1, the thickness of the slice is 0.3mm-0.8mm.

[0027] Furthermore, the scanning parameters in step S2 include scanning spacing and scanning speed, with the scanning spacing ranging from 0.2 mm to 1.2 mm and the scanning speed ranging from 200 mm / min to 1200 mm / min.

[0028] Furthermore, in step S3, the laser power range of the laser beam output component 1 is 400W-2000W, and the laser spot diameter of the laser beam output component 1 is 0.6mm-2mm.

[0029] Furthermore, in step S4, the flow rate of the metal powder in the powder feeding assembly 5 is 5 g / min-25 g / min, and the protective gas output from the protective gas path 13 is an inert gas with a flow rate of 6 L / min-15 L / min and a pressure of 0.1 MPa-0.5 MPa. This ensures that the powder deposition efficiency is between 60% and 90%, and controls the melt channel forming height to be between 0.3 mm and 1.3 mm, and the melt channel width to be between 0.8 mm and 1.5 mm.

[0030] Furthermore, based on the arrangement of the laser beam output component 1, the single-layer scanning width is adjusted in real time to ensure continuous layer coverage and no obvious gaps between forming channels. The scanning width is mainly determined by the spot diameter, spot spacing, and scanning channel overlap rate. The typical inter-channel overlap rate is controlled in the range of 20%-45%, which can be adjusted according to the material wettability and molten pool stability; the scanning width is adjustable in the range of 1mm-5mm (determined by the number of array beams). By correcting the array beam spacing, adjusting the energy distribution, and optimizing the scanning path spacing, continuous cladding of the array channels in the layer direction is achieved, improving the interlayer bonding quality and avoiding heat accumulation caused by unfused areas or excessive overlap of the molten pool.

[0031] Furthermore, steps S5 and S6 also include surface smoothing adjustment, solidification adjustment control, and residual stress control.

[0032] By controlling the single-pass forming height and the multi-pass cumulative height, a uniform and continuous surface is formed. Through combined adjustment of laser power, scanning speed, powder mass flow rate, and powder feed angle, the surface tension and flowability of the molten pool are maintained within a stable range, with a typical single-layer forming height maintained at 0.6mm-1.5mm. Dynamic balancing compensation of the array beam output eliminates surface ripples and height errors caused by energy differences between different beams in the array. If necessary, a uniform energy scan (power 200W-600W) can be performed between layers to shallowly melt micro-protrusion areas on the surface, adjusting surface smoothness and improving the deposition stability and forming accuracy of the next layer.

[0033] By controlling the temperature field to influence the solidification rate of the molten pool, the grain morphology, microstructure, and thermal stress level can be optimized. During scanning, the array laser creates a controllable intralayer temperature gradient by adjusting the power of each laser beam, the scanning sequence, and the scanning strategy (such as staggered scanning, rotating scanning, island scanning, etc.). The solidification cooling rate is maintained at 10... 3 K / s-10 5 The K / s range is used to obtain fine equiaxed or weakly preferred columnar crystals, reducing the tendency for macroscopic hot cracking. At the same time, preheating the substrate (100℃-350℃ range, depending on the material selection) can reduce the interlayer temperature gradient, avoid high residual stress caused by rapid cooling, and improve the uniformity of the microstructure after forming.

[0034] After multi-layer scanning, the part will accumulate thermal stress. An array laser is used to perform a "stress relief scan" on the layers. Without powder feeding, the surface is uniformly irradiated with low power (200W-800W) and a high scanning speed (600mm / min-1500mm / min), causing a slight thermal relaxation effect on the surface layer. This releases some residual tensile stress and inhibits warping and crack formation. This process can be performed once after every 3-8 layers, with the frequency adjusted according to the part size and actual temperature rise.

[0035] For multi-material fabrication, a multi-channel powder feeding system is used to proportionally adjust the mass flow rate of different powder materials, achieving layer-by-layer transitions or regional deposition of different materials. The powder flow rate of a single channel is maintained at 5 g / min-25 g / min, and multi-material powder feeding is proportionally controlled to meet the composition design requirements (with an error typically of ±2%-5%). Array lasers are used in multi-material forming to adjust the local energy density to match the melting point, absorbance, and flowability of different materials, ensuring metallurgical bonding at the interface rather than brittle fracture. Typical applications include: wear-resistant / high-toughness bilayer materials, nickel-based / titanium-based transition structures, and gradient thermal expansion coefficient structures. Interface cleanliness and smooth compositional transitions can be ensured through material switching delay compensation and powder dwell time control.

[0036] After interlayer processing is completed, the deposition, scanning, solidification, stress release, and local correction steps are repeated layer by layer according to the slicing plan until all layers are completed. The entire process relies on a real-time monitoring system (melt pool temperature monitoring, optical forming monitoring, powder deposition tracking, etc.) for process quality feedback and parameter fine-tuning to ensure that the overall dimensional accuracy, microstructure uniformity, and forming quality of the part meet the design requirements. The final result is a complex multi-material or single-material component with complete forming, high internal density, and low residual stress.

[0037] An array-type laser additive manufacturing apparatus for realizing an array-type laser additive manufacturing method includes multiple laser beam output components 1, multiple powder feeding components 5, multiple protective gas paths 13, a water cooling system 16, a powder conveying system 18, and an optical fiber 23. The multiple powder feeding components 5 are arranged in an array, the multiple laser beam output components 1 are arranged in an array on both sides of the powder feeding components 5, the multiple protective gas paths 13 are arranged in an array on both sides of the powder feeding components 5 and located between the powder feeding components 5 and the laser beam output components 1, the laser beam output components 1 are connected to the optical fiber 23, the powder feeding components 5 are connected to the powder conveying system 18, and the water cooling system 16 is correspondingly arranged to the powder conveying system 18.

[0038] Example: The array-type laser additive manufacturing device in this embodiment mainly consists of a laser beam output component 1, a powder feeding component 5, a protective gas path 13, a water cooling system 16, and a powder conveying system 18.

[0039] The laser beam is transmitted through optical fiber 23 into the device and emitted sequentially from multiple laser beam output components 1, forming an array of multi-path laser beams. These laser beams create an energy overlap zone on the workpiece surface to establish a stable molten pool. Powders of different materials are fed into the molten pool from the powder feeding component 5. Protective gas path 13 continuously sprays protective gas on both sides of the powder feeding component 5, forming a protective gas curtain covering the molten pool and powder flow. This prevents oxidation, nitrogen absorption, and processing spatter from affecting the stability of the molten pool, thus ensuring forming quality and maintaining stable temperatures for optical components and structural parts under high-energy-density processing conditions. This ensures consistent output and processing stability of the array laser. Through the coupling of multiple laser beams and multi-path powder injection, wide-area, high-efficiency, and highly consistent metal additive manufacturing and cladding processes can be achieved.

[0040] Multi-beam, multi-powder flow configuration: The versatility of laser beams: Different laser beams have different powers, which can be adjusted according to actual processing needs. For example, when manufacturing larger or thicker parts, the laser power can be increased to effectively melt more powder; while in areas with more complex details, the laser power can be appropriately reduced to avoid overheating and deformation.

[0041] Powder flow diversity: Adjusting the powder flow rate ensures that each laser beam receives the appropriate amount of powder, guaranteeing that each area of ​​the molten pool has sufficient powder supply, thus avoiding forming defects caused by insufficient powder.

[0042] Independent control: Independent laser control: Each laser beam in the array can be independently controlled. Each laser has its own separate control channel, allowing for individual power settings and enabling or disabling. This beam-by-beam independent control method enables the system to output appropriate energy for each laser beam based on the actual needs of different locations, achieving more flexible and precise processing results.

[0043] Independent powder control: Each powder channel has independent control capabilities. Each powder channel corresponds to an independent powder supply unit, which can control the start / stop of the powder, the switching of the supply path, the selection of powder type, and the timing of the powder entering the processing area, thereby achieving independent operation between channels without interference. Through this channel-by-channel independent powder control method, the system can obtain different types or combinations of powder materials at different locations according to actual forming requirements, significantly improving the flexibility of material configuration.

[0044] Precise control of the forming area: Multi-zone melting and deposition: When dealing with large or multi-zone parts, array-type laser powder feeders can ensure differences in laser power and powder delivery volume in different zones. For example, for parts with uneven thickness, the laser power can be adjusted to ensure that thicker areas are fully melted while thinner areas are prevented from overheating.

[0045] Localized fine machining: This system can perform localized fine machining according to the needs of different parts of the part. For example, on complex structures, the array-type laser powder feeder can use higher laser power and more powder flow in specific areas to ensure high-quality forming in these areas.

[0046] The array-based approach of this invention precisely controls the additive manufacturing width by adjusting the number of laser units and the laser power. In a multi-row array, the processing area can be expanded through staggered arrangement and overlapping control, achieving seamless, wide-width forming; it can also be coordinated with powder flow rate and scanning speed for linked control. This design is particularly suitable for manufacturing complex structural parts with high precision and continuity requirements.

[0047] The width of the additive manufacturing process is controlled by switching on and off the number of laser beams and the number of powder feed nozzles. When a single laser beam is working, the width of the cladding track formed is mainly determined by the spot size of that laser beam. However, when multiple laser beams are turned on simultaneously, with adjacent spots superimposed or combined, the width of the cladding track increases significantly with the increase in the number of laser beams on. In other words, the more laser beams on, the wider the track formed by the combined action of multiple spots, allowing for a larger area of ​​material cladding.

[0048] Figures 6 to 12It represents an array of eight laser beams and four metal powders, with multiple control modes. 1-4 and 9-12 are laser beams, and 5-8 are metal powders. The laser power can be adjusted as needed to generate a specific temperature gradient. Figures 7 to 11 In the middle, from left to right, are a schematic diagram of laser power, a schematic diagram of the molten pool shape, and a schematic diagram of the processing process.

[0049] First control mode: 1, 2, 3, 4 on, 9, 10, 11, 12 off; The laser is turned on only in the first four positions and off in the last four, making it suitable for high-precision, small-area laser deposition. This configuration is ideal for scenarios requiring fine machining or localized repair, such as the precision machining of small parts. Local temperatures can be controlled by adjusting the laser power, ensuring precise heat input to the manufactured area.

[0050] Heating is performed only at the first four lasers, allowing for controlled temperature and cooling rates in localized areas. The relatively small heat input results in a faster cooling rate, which helps control the material's solidification process. Because the laser energy is concentrated in a small area, the cooling rate can be finely adjusted locally, contributing to the formation of fine grain structures and improving the material's density and strength.

[0051] Concentrated laser heating creates a large thermal gradient, but due to the small heating area and high cooling rate, residual stress formation is relatively small. During manufacturing, areas with high temperature gradients are cooled more quickly, effectively reducing thermal stress. For even better heat treatment results (e.g., stress relief or surface strengthening), the laser power can be adjusted to further regulate the heat input, resulting in more uniform grain size and deposition layers.

[0052] Second control mode: Laser fully on; With all eight lasers activated, the entire area will be simultaneously irradiated, making it suitable for rapid, large-scale material deposition. It is well-suited for applications requiring uniform deposition over large areas, such as fabricating large structures or performing large-scale additive manufacturing. Simultaneous laser activation helps increase the deposition rate, but careful control of heat input is necessary to avoid overheating or deformation of the material.

[0053] With all eight lasers activated simultaneously, the heating area becomes very extensive, and the cooling rate may be slow, making it suitable for large-area deposition requiring significant heat input. Higher laser power and longer heating times can lead to slower cooling rates, potentially resulting in larger grain sizes. In such cases, controlling the cooling rate is crucial to avoid porosity or cracks.

[0054] Turning on all lasers creates a significant temperature gradient, potentially leading to high residual stress throughout the workpiece. To avoid excessive thermal stress, the temperature gradient needs to be balanced by controlling the cooling rate, thereby reducing localized thermal deformation. Adjusting the laser power and scanning path can help regulate the material's curing process, preventing excessive stress accumulation and improving the durability and crack resistance of the final part.

[0055] Third control mode: Laser fully on, with high power in modes 1, 4, 9, and 12, and low power in modes 2, 3, 10, and 11; With only some lasers activated, and some of these lasers having higher power, this configuration is suitable for localized deposition with concentrated energy. In this configuration, the energy is mainly concentrated in lasers 1, 4, 9, and 12, which may be suitable for applications requiring higher energy density, such as hardening, melting, or high-intensity deposition.

[0056] In this configuration, the control of laser power allows for greater heat input to localized areas of material deposition. This localized heating increases the temperature of the deposition region, promoting rapid melting and deposition of the material. The faster cooling rate helps achieve uniform solidification, making it suitable for applications with stringent grain size requirements. Controlling the cooling rate has a significant impact on the material's microstructure.

[0057] When a high-power laser is activated, a strong temperature gradient may be generated due to significant temperature differences in the locally heated areas. This temperature gradient can lead to the accumulation of residual stress. However, by controlling the cooling rate, stress accumulation can be effectively reduced. For example, gradual cooling can avoid cracking and deformation problems caused by rapid cooling.

[0058] Fourth control mode: Laser fully on, modes 1, 4, 9, and 12 have low power, modes 2, 3, 10, and 11 have high power; In contrast to the previous control mode, this setup concentrates less power on some lasers while using more power on others. It is suitable for finer, localized deposition, and the use of high-power lasers to cover a larger area can help control temperature gradients in different regions. This configuration is suitable for manufacturing parts with specific requirements for heat distribution, such as metallic materials requiring multi-stage heat treatment.

[0059] Low-power lasers are used for heating at positions 1, 4, 9, and 12, effectively controlling the melting and cooling rates of the material. This configuration achieves lower heat input, making it suitable for applications with a small heat-affected zone. The faster cooling rate of this configuration helps form a more uniform microstructure, suitable for fine deposition requirements.

[0060] Although the power is relatively low and the temperature gradient may be relatively low, the laser covers a larger area, which may result in a more uniform heat input distribution. In this configuration, residual stress control becomes more important. By adjusting the cooling rate and laser scanning path, the adverse effects of the temperature gradient can be reduced, and excessive thermal stress accumulation can be avoided.

[0061] Fifth control mode: Laser beams 1, 2, 3, 9, 10, and 11 are on, metal powder 6 is on; This configuration shuts off the supply of metal powders 5, 7, and 8 simultaneously with laser activation, thus preventing unnecessary powder introduction or deposition and making it suitable for delicate post-processing work. It is applicable to applications requiring precise control of laser energy and powder deposition, such as surface repair or localized strengthening.

[0062] This means that the powder supply and deposition rate can be precisely controlled during the deposition process. Controlling the cooling rate and heat input ensures the stability of the solidification process while avoiding metal deformation or uneven solidification caused by overheating.

[0063] Because only specific areas are heated, the temperature gradient is relatively small, which helps reduce residual stress. By adjusting the cooling rate, laser scanning path, and power, the heat input can be effectively controlled, thus mitigating the temperature gradient and preventing the generation of large-scale thermal stress.

[0064] This invention arranges multiple laser beam output components 1 and powder feeding components 5 in a specific manner within a certain space, allowing each laser to operate independently or collaboratively. The switching and power of each laser can be individually controlled.

[0065] The additive width can be continuously controlled by adjusting the number of beams, beam spacing, spot diameter, and overlap rate. By selecting different array numbers and rationally configuring beam spacing and overlap rate, a seamless splicing processing mode from narrow track to wide area coverage can be achieved. Furthermore, the track width and deposition stability can be further optimized by combining powder flow rate and scanning speed, thereby meeting the differentiated requirements of different component areas in terms of accuracy and efficiency.

[0066] By coordinating and controlling laser power, scanning speed, beam arrangement, and scanning strategy, precise control of the molten pool temperature gradient is achieved. Increasing the central energy density and scanning speed yields a fine equiaxed crystal structure. Preheating the substrate, reducing laser power, or employing a slow cooling strategy effectively reduces the temperature gradient, residual stress, and the tendency for hot cracking. The array of multi-beam lasers offers the advantage of independently controllable energy input. Through a three-stage energy design—preheating the leader, the central molten pool, and slow cooling at the rear—a programmable temperature field can be formed within the layer, making solidification conditions more controllable and achieving synergistic optimization of microstructure refinement, stress suppression, and improved forming quality. To clarify, temperature gradient control is achieved through active surface control of the formed material via single-pass height control, inter-pass overlap adjustment, array beam coordinated scanning, and surface remelting finishing. By adjusting powder flow rate and laser power, the deposition height of each pass is kept consistent. Utilizing synchronous or staggered scanning modes of the array beam allows subsequent beams to perform slight remelting of the previous melt pool. Furthermore, employing low-power, powder-free flattening scanning during multilayer deposition further eliminates surface ripples and improves layer smoothness. Through these combined methods, the interlayer step effect is significantly reduced, resulting in a consistently high level of additive surface quality and providing a good substrate for subsequent multilayer forming.

[0067] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "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, and are only for the convenience of describing this invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0068] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made to the technical solutions of the present invention by those skilled in the art without departing from the spirit of the present invention should fall within the protection scope of the present invention.

Claims

1. An array-type laser additive manufacturing method, characterized in that, Includes the following steps: S1. Importing and Layering the Model: Import the 3D model of the part into the system, slice it into layers along the additive manufacturing direction, and set the thickness of each layer. S2, Scan Path Planning and Filling Settings: Plan the scan path of the array laser for each slice and set the scan parameters; S3, array-type laser synchronous output control, multiple array-set laser beam output components (1) output synchronously or according to strategy according to the planned scanning path to form a molten pool; S4. Powder flow and powder feeding path control: Multiple array-set powder feeding components (5) feed metal powder into the molten pool formed in S3, and at the same time output protective gas through the protective gas path (13). S5. Based on the width of the additive manufacturing process, control the opening or closing of the middle part of the laser beam output component (1) of the multiple arrays to adjust the width of the single-pass cladding in real time. S6. Based on the additive slicing layer material, the matching material is delivered through multiple array-set powder feeding components (5); S7. Repeat S1-S6, stacking layer by layer until the part is manufactured.

2. The array-type laser additive manufacturing method according to claim 1, characterized in that, In step S1, the thickness of the slice is 0.3mm-0.8mm.

3. The array-type laser additive manufacturing method according to claim 1, characterized in that, The scanning parameters in step S2 include scanning spacing and scanning speed. The scanning spacing ranges from 0.2 mm to 1.2 mm, and the scanning speed ranges from 200 mm / min to 1200 mm / min.

4. The array-type laser additive manufacturing method according to claim 1, characterized in that, In step S3, the laser power range of the laser beam output component (1) is 400W-2000W, and the laser spot diameter of the laser beam output component (1) is 0.6mm-2mm.

5. The array-type laser additive manufacturing method according to claim 1, characterized in that, In step S4, the flow rate of the metal powder in the powder feeding component (5) is 5 g / min-25 g / min, and the protective gas output by the protective gas path (13) is an inert gas with a flow rate of 6 L / min-15 L / min and a pressure of 0.1 MPa-0.5 MPa.

6. The array-type laser additive manufacturing method according to claim 1, characterized in that, In step S5, the scanning width can be adjusted from 1mm to 5mm.

7. The array-type laser additive manufacturing method according to claim 1, characterized in that, Between steps S5 and S6, there are also surface smoothing adjustment, solidification adjustment control and residual stress control.

8. The array-type laser additive manufacturing method according to claim 7, characterized in that, During solidification regulation control, the solidification cooling rate is 10. 3 K / s-10 5 When participating in stress control, the laser beam output component (1) is used to irradiate the forming surface with energy. The power of the laser beam output component (1) during energy irradiation is 200W-800W.

9. The array-type laser additive manufacturing method according to claim 1, characterized in that, In step S6, the flow rate of metal powder in a single powder feeding component (5) is 5 g / min-25 g / min, and the proportion of metal powder in multiple powder feeding components (5) is determined according to the component design requirements.

10. An array-type laser additive manufacturing apparatus for implementing the array-type laser additive manufacturing method according to any one of claims 1-9, characterized in that, It includes multiple laser beam output components (1), multiple powder feeding components (5), multiple protective gas paths (13), a water cooling system (16), a powder conveying system (18), and an optical fiber (23). The multiple powder feeding components (5) are arranged in an array. The multiple laser beam output components (1) are arranged in an array on both sides of the powder feeding components (5). The multiple protective gas paths (13) are arranged in an array on both sides of the powder feeding components (5) and located between the powder feeding components (5) and the laser beam output components (1). The laser beam output components (1) are connected to the optical fiber (23). The powder feeding components (5) are connected to the powder conveying system (18). The water cooling system (16) is correspondingly arranged to the powder conveying system (18).

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