A functional gradient particulate reinforced composite laser additive manufacturing apparatus

Abstract

The present application belongs to the technical field of laser additive manufacturing, and discloses a kind of functional gradient particle reinforced composite laser additive manufacturing equipment, comprising: laser generating device, electromagnetic generating device, work platform, workpiece translation mechanism, workpiece clamping device, powder feeding device, wire feeding device;The present application solves the problem of the absence of reinforcing particles in the forming process: compared with the traditional powder feeding type and wire feeding type LDED forming equipment, the present equipment adopts wire powder co-feeding forming, by adjusting the relative pose of laser, powder and wire, the heating object of laser is metal wire, reinforcing particles can avoid direct radiation of laser, effectively solve the problem that reinforcing particles in FGM-PMMC have low solubility and metal matrix cannot be fully melted simultaneously. Realize the flexible control of FGM-PMMC composition and structure gradient.

Description

Technical Field

[0001] This invention belongs to the field of laser additive manufacturing technology, and particularly relates to a laser additive manufacturing equipment for functionally graded particle-reinforced composites. Background Technology

[0002] Functionally graded particle-reinforced metal matrix composites (FGM-PMMCs) combine the high hardness and wear resistance of ceramic particles with the high toughness and ductility of metal matrices, achieving continuous gradients in composition and structure. This overcomes the limitations of traditional single-material properties and occupies an important position in the field of special materials. For example, the inner wall of rocket engine nozzles uses FGM-PMMC with high SiC content and low Al content to provide high-temperature ablation resistance, while the outer layer uses FGM-PMMC with low SiC content and high Al content to improve thermal conductivity. Marine engineering equipment power system blades use high Ti content in the inner layer and low Ti content and high WC particle content in the outer layer to improve blade wear resistance. Currently, commercially available FGM-PMMCs are typically prepared using traditional methods such as high-temperature hot pressing, casting, and spark plasma sintering. In contrast, additive manufacturing methods, represented by laser-directed energy deposition (LDED), offer numerous advantages such as high efficiency and low cost, customized / functionally graded design, applicability to complex and irregular structures, and wide material adaptability. These advantages provide an effective means for high-quality and efficient forming and manufacturing of FGM-PMMCs, and they are gradually moving towards engineering applications.

[0003] LDED technology can be divided into powder-feed and wire-feed types based on the type of material fed. Powder-feed LDED uses a bypass or coaxial method to transport different types of metal / ceramic powders, and controls the laser melting of the powder to prepare FGM-PMMC. However, because the metal and ceramic powders are mixed, the ceramic particles are prone to melting or vaporization under high-energy laser irradiation. Adjusting only the powder feeding parameters (such as feed rate, speed, and angle) and laser parameters (power, speed, etc.) has a very limited effect on the distribution and content of ceramic particles in the metal matrix after forming, making it difficult to achieve the expected functionally graded structure and strengthening effect of FGM-PMMC. In contrast, wire-feed laser deposition technology has received increasing attention in recent years due to its high efficiency, high material utilization, and lower equipment requirements. Nevertheless, due to the high cost and complex process of preparing FGM-PMMC filaments, there are currently very few reports on the preparation of FGM-PMMC using wire-feed laser deposition technology.

[0004] Based on the above analysis, the problems and shortcomings of the existing technology are as follows:

[0005] Because metal powder and ceramic powder are mixed together, ceramic particles are prone to melting or vaporization under the action of high-energy laser. Adjusting only the powder feeding parameters (such as powder amount, speed, angle, etc.) and laser parameters (power, speed, etc.) has a very limited effect on the distribution and content of ceramic particles in the metal matrix after forming, making it difficult to achieve the expected functional gradient structure and strengthening effect of FGM-PMMC. Summary of the Invention

[0006] To address the problems existing in the prior art, this invention provides a laser additive manufacturing equipment for functionally graded particle-reinforced composites.

[0007] This invention is implemented as follows: a laser additive manufacturing equipment for functionally graded particle-reinforced composites includes:

[0008] Laser generator, electromagnetic generator, work platform, workpiece translation mechanism, workpiece clamping device, powder feeding device, wire feeding device;

[0009] The laser generating device includes a high-power laser head, and the powder feeding device and the wire feeding device are respectively connected to the two sides of the high-power laser head through corner bracket connectors; the overall structure formed by connecting the laser generating device, the powder feeding device and the wire feeding device is "L" shaped.

[0010] Furthermore, the powder feeding device includes a powder feeding nozzle, a powder feeding quick-connect connector, a protective air quick-connect connector, a dovetail groove type two-degree-of-freedom adjustment device, and an angle code connector.

[0011] Furthermore, the powder feeding nozzle of the powder feeding device is divided into inner and outer layers: the inner layer is provided with one powder outlet hole, which is used to feed powder by air; the outer layer is provided with 10 protective air outlet holes, which are arranged coaxially with the powder outlet hole to constrain the powder action area.

[0012] Furthermore, the wire feeding device includes a wire feeding gun, a dovetail groove type two-degree-of-freedom adjustment device, a single-degree-of-freedom slide table, and corner code connectors.

[0013] Furthermore, the electromagnetic generating device includes an electromagnetic generating pole, a coil, an inner partition, a transverse yoke, a vertical yoke, a column sleeve, a lead screw, a pressure cover, an outer partition, and a 3P terminal block; by determining the target distribution gradient of the reinforcing particles in the functionally graded particle-reinforced metal matrix composite (FGM-PMMC), the magnitude / direction of the electromagnetic field and the directional Lorentz force it generates can be specifically controlled.

[0014] Furthermore, the workpiece translation mechanism includes a servo motor, a ball bearing nut mounting plate, a sensing plate, three U-shaped photoelectric sensors, and a screw drive device. Based on the set speed and moving distance, it works with the U-shaped photoelectric sensors to achieve high-precision movement through the screw drive device. In conjunction with the electromagnetic generator, it ensures the stability of the electromagnetic field by moving the workpiece while keeping the electromagnetic field fixed. The workpiece clamping device includes a clamping support, four adjusting fastening screws, and four workpiece pressure plates. It can adapt to workpieces of different thicknesses by adjusting the different fastening states of the fastening screws.

[0015] Furthermore, the work platform includes a fixed caster wheel, a work surface component, and a work platform support component.

[0016] Based on the above technical solutions and the technical problems solved, the advantages and positive effects of the technical solution to be protected by this invention are as follows:

[0017] First, this invention designs a laser-directed energy deposition (EDD) device for functionally graded particle-reinforced composites. It mainly consists of key components such as a laser generator, a powder feeding device, a wire feeding device, and an electromagnetic generator. Its principle is to simultaneously feed ceramic powder and metal wire while the laser scans. By adjusting the relative positions of the wire, powder, and laser, it achieves minimal powder melting and complete metal wire melting; simultaneously, by controlling the powder feeding amount, it achieves precise control of the FGM-PMMC reinforcing particle content. The electromagnetic generator can generate a directional Lorentz force on the molten metal pool. By adjusting the magnitude and direction of the Lorentz force, it achieves flexible and controllable distribution of reinforcing particles in the FGM-PMMC, meeting its compositional and structural gradient requirements. It is worth mentioning that the novel equipment designed in this invention will also be applied to other laser manufacturing fields.

[0018] Laser-directed energy deposition (LDED) technology provides an effective means for the high-quality and efficient forming and manufacturing of functionally graded particle-reinforced metal matrix composites (FGM-PMMC). However, it faces the challenge of controlling the content and distribution of reinforcing particles after forming, making it difficult to achieve the expected functionally graded structure and performance requirements of FGM-PMMC. To address these issues, this invention designs a laser-directed energy deposition equipment for functionally graded particle-reinforced composites, specifically a laser energy deposition equipment based on electromagnetic field-filament / powder co-feeding synergistic forming. It mainly consists of key components such as a laser generator, a powder feeding device, a filament feeding device, and an electromagnetic generator. The equipment designed in this invention has the following advantages:

[0019] 1. Solved the problem of missing reinforcing particles during the forming process: Compared with traditional powder feeding and wire feeding LDED forming equipment, this equipment adopts wire and powder co-feeding forming. By adjusting the relative positions of the laser, powder and wire, the laser heats the metal wire, and the reinforcing particles can avoid direct laser radiation. This effectively solves the problem that the requirements for low melting degree of reinforcing particles and full melting of the metal matrix in FGM-PMMC cannot be met at the same time.

[0020] 2. Achieved flexible and controllable composition and structural gradient of FGM-PMMC: Compared with traditional LDED forming equipment, this equipment is equipped with an electromagnetic field generator while forming the filament powder. By determining the target distribution gradient of reinforcing particles in FGM-PMMC, the magnitude / direction of the electromagnetic field and the directional Lorentz force generated therefrom can be designed in a targeted manner, thereby achieving flexible and controllable distribution of reinforcing particles.

[0021] 3. Higher efficiency and lower cost while ensuring performance: The co-feeding device of this equipment combines the advantages of good formability and low cost of powder-fed LDED with the high efficiency and high material utilization of wire-fed LDED. Furthermore, to meet performance requirements, FGM-PMMC formed using traditional LDED equipment typically requires pre-treatment and post-treatment. This equipment, however, uses electromagnetic field-wire-feeding co-feeding to form FGM-PMMC in a single step, satisfying its performance and functional gradient requirements and further improving processing efficiency.

[0022] 4. Wider adaptability to LDED forming processes: The wire-powder co-feeding device designed in this equipment has 5 degrees of freedom adjustable function in space. By adjusting the relative poses of the light-wire, light-powder, and wire-powder, the characteristics of the molten pool, powder migration behavior, and wire melting behavior can be flexibly and controllably adjusted, thus meeting more laser energy deposition process requirements.

[0023] 5. Ensures the stability of processing parameters: The electromagnetic generator is designed with a translation mechanism. During processing, the workpiece is moved while the laser head, wire feeding device, powder feeding device, and electric / magnetic field generator remain stationary. This ensures that the electromagnetic field strength remains unchanged throughout the entire processing process.

[0024] 6. Applicable to other laser processing fields: Because this device is equipped with a multi-degree-of-freedom adjustable wire feeding mechanism, powder feeding mechanism and electromagnetic generator, this equipment can also be applied to various laser processing technologies such as laser-arc hybrid welding, laser multi-energy field welding, laser powder feeding welding, laser cladding, and laser injection.

[0025] This invention proposes a laser additive manufacturing equipment for functionally graded particle-reinforced composites (FGM-PMMCs), which effectively solves the problem of difficult-to-control particle distribution in traditional LDED technology. By using a co-feeding method, this equipment avoids particle loss due to direct laser radiation while simultaneously achieving full melting of the metal matrix, thus balancing the performance requirements of different components in the composite material. Furthermore, the equipped electromagnetic field generator flexibly adjusts the particle distribution gradient by generating directional Lorentz forces, meeting the stringent requirements of FGM-PMMCs for composition and structural gradients. Compared to traditional LDED equipment, this invention achieves a good balance between high efficiency and high performance. The co-feeding device combines the low cost of powder-feed LDED with the high material utilization of wire-feed LDED, and through the synergistic effect of the electromagnetic field, achieves one-time forming of FGM-PMMCs, eliminating cumbersome pre- and post-processing steps, significantly improving processing efficiency and reducing manufacturing costs. In addition, the 5-DOF adjustable mechanism designed for this equipment gives it a wide range of process adaptability. By adjusting the relative positions of the laser, powder and wire, the characteristics of the molten pool and the material migration behavior can be flexibly controlled. It is suitable for a variety of laser processing scenarios, including laser-arc hybrid welding, laser multi-energy field welding, laser powder feeding welding, laser cladding, laser injection and other fields.

[0026] Does the technical solution of this invention solve a technical problem that people have long desired to solve but have never been able to successfully address?

[0027] By employing a wire-powder co-feeding forming process, this equipment optimizes the relative orientation of the laser, powder, and wire, enabling the metal wire to be the primary heating element. This effectively avoids direct laser radiation to the reinforcing particles, thus balancing the low melting point requirement of the reinforcing particles in FGM-PMMC with the requirement for full melting of the metal matrix. It solves the problem of missing reinforcing particles in traditional powder-feeding and wire-feeding LDED forming. The equipped electromagnetic field generator produces directional Lorentz forces, flexibly adjusting the particle distribution gradient to meet the stringent requirements of FGM-PMMC for composition and structural gradients. Balancing forming, efficiency, and cost, this equipment achieves higher efficiency and lower cost while ensuring performance, and shows broad prospects in laser-arc hybrid welding, laser multi-energy field welding, laser powder-feeding welding, laser cladding, and laser injection welding. Attached Figure Description

[0028] Figure 1 This is a structural diagram of the laser additive manufacturing equipment for functionally graded particle-reinforced composites provided in an embodiment of the present invention;

[0029] Figure 2 This is a structural layout diagram of the laser generating device, wire feeding device, and powder feeding device provided in the embodiments of the present invention;

[0030] Figure 3This is a schematic diagram of the powder feeding device provided in an embodiment of the present invention;

[0031] Figure 4 This is a partially enlarged view of the powder feeding nozzle of the powder feeding device provided in an embodiment of the present invention;

[0032] Figure 5 This is a schematic diagram of the wire feeding device provided in an embodiment of the present invention;

[0033] Figure 6 This is a schematic diagram of the electromagnetic generator structure provided in an embodiment of the present invention;

[0034] Figure 7 This is a schematic diagram of the workpiece translation mechanism and workpiece clamping device provided in the embodiments of the present invention;

[0035] Figure 8 This is a schematic diagram of the working platform structure provided in an embodiment of the present invention;

[0036] Figure 9 This is a diagram showing the experimental results of using this equipment to control the porosity of the weld seam during laser welding, as provided in an embodiment of the present invention.

[0037] Figure 10 This is a diagram showing the test results of applying an electric field using this equipment during laser welding, as provided in an embodiment of the present invention.

[0038] In the diagram: 1. Laser generator; 2. Electromagnetic generator; 3. Working platform; 4. Workpiece translation mechanism; 5. Workpiece clamping device; 6. Powder feeding device; 7. Wire feeding device; 8. Angle code connector; 9. Workpiece; 1-1. High-power laser head; 2-1. Electromagnetic generator pole; 2-2. Wire coil; 2-3. Inner partition; 2-4. Horizontal yoke; 2-5. Vertical yoke; 2-6. Column sleeve; 2-7. Lead screw; 2-8. Pressure cap; 2-9. Outer partition; 2-10. 3P terminal block; 3-1. Fixable caster wheel; 3-2. Working plane component; 3-3. Working surface 4-1. Support component; 4-2. Servo motor; 4-3. Ball bearing nut mounting plate; 4-4. Induction plate; 4-5. U-shaped photoelectric sensor; 4-6. Screw drive device; 5-1. Clamping support component; 5-2. Adjusting fastening screw; 5-3. Workpiece pressure plate; 6-1. Powder feeding nozzle; 6-2. Powder feeding quick connector; 6-3. Protective gas quick connector; 6-4. Dovetail groove type two-degree-of-freedom adjustment device; 6-5. Powder outlet hole; 6-6. Protective gas outlet hole; 7-1. Wire feeding gun; 7-2. Dovetail groove type two-degree-of-freedom adjustment device; 7-3. Single-degree-of-freedom slide table. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0040] like Figure 1 As shown, an embodiment of the present invention provides a laser additive manufacturing equipment for functionally graded particle-reinforced composites, comprising:

[0041] It includes a laser generator 1, an electromagnetic generator 2, a working platform 3, a workpiece translation mechanism 4, a workpiece clamping device 5, a powder feeding device 6, and a wire feeding device 7.

[0042] The laser generating device 1 includes a high-power laser head 1-1, with a powder feeding device 6 and a wire feeding device 7 respectively connected to both sides of the high-power laser head 1-1 via angle bracket connectors 8. The overall structure formed by connecting the laser generating device, the powder feeding device, and the wire feeding device is L-shaped, occupying little space and offering flexible application scenarios, such as... Figure 2 As shown.

[0043] The powder feeding device 6 includes a powder feeding nozzle 6-1, a powder feeding quick-connect connector 6-2, a protective gas quick-connect connector 6-3, a dovetail-groove two-degree-of-freedom adjustment device 6-4, and an angle bracket connector 8, which can realize the position and posture adjustment of the powder feeding device 2. Figure 3 As shown.

[0044] like Figure 4 As shown in the enlarged view, the powder feeding nozzle 6-1 of the powder feeding device 6 is divided into inner and outer layers: the inner layer is provided with one powder outlet hole 6-5, which is used to feed powder by air; the outer layer is provided with 10 protective air outlet holes 6-6, which are arranged coaxially with the powder outlet hole to constrain the powder action area.

[0045] The wire feeding device 7 includes a wire feeding gun 7-1, a dovetail groove type two-degree-of-freedom adjustment device 7-2, a single-degree-of-freedom slide table 7-3, and an angle code connector 8, which can realize the position and posture adjustment of the wire feeding device in three degrees of freedom, such as... Figure 5 As shown.

[0046] The electromagnetic generating device 2 of this invention includes an electromagnetic generating pole 2-1, a coil 2-2, an inner partition 2-3, a horizontal yoke 2-4, a vertical yoke 2-5, a column sleeve 2-6, a lead screw 2-7, a pressure cap 2-8, an outer partition 2-9, and a 3P terminal block 2-10, as shown. Figure 6 As shown. By determining the target distribution gradient of the reinforcing particles in FGM-PMMC, and then selectively controlling the magnitude / direction of the electromagnetic field and the resulting directional Lorentz force, flexible and controllable distribution of the reinforcing particles can be achieved.

[0047] This device achieves high-precision machining of workpiece 9 through the coordinated operation of a laser generator 1 and an electromagnetic generator 2. The high-power laser head 1-1 in the laser generator 1 emits a laser beam, locally heating the workpiece surface. Simultaneously, the electromagnetic generator pole 2-1 and coil 2-2 in the electromagnetic generator 2 generate a strong electromagnetic field. This stable electromagnetic field controls the internal thermoelectric effect of the workpiece, thereby optimizing machining quality. Workpiece 9 is mounted on the work platform 3, and the machining area is dynamically adjusted via a workpiece translation mechanism 4, ensuring high-precision positioning and stability.

[0048] The workpiece translation mechanism 4 is driven by a servo motor 4-1, which in turn moves the workpiece via a ball bearing nut mounting plate 4-2 and a screw drive 4-5. The movement process is monitored in real-time by a U-shaped photoelectric sensor 4-4 and an induction plate 4-3 to ensure precise movement. The workpiece clamping device 5 securely clamps workpieces of different thicknesses and sizes through a clamping support 5-1, adjusting fastening screws 5-2, and a workpiece pressure plate 5-3. The clamping device is connected to an electric field power supply to ensure a stable electric field is formed inside the workpiece during processing, improving processing consistency.

[0049] The powder feeding device 6 and the wire feeding device 7 are responsible for the precise supply of processing materials. The powder feeding device 6 evenly sprays powder material into the processing area through the powder feeding nozzle 6-1. The protective gas quick-connect connector 6-3, in conjunction with the protective gas outlet 6-6, provides a protective atmosphere to prevent oxidation or contamination during processing. The wire feeding device 7 achieves precise feeding of the welding wire through the wire feeding gun 7-1 and the single-degree-of-freedom slide 7-3. The dovetail-groove two-degree-of-freedom adjustment devices 6-4 and 7-2 ensure precise adjustment of the spatial angles of the powder feeding nozzle and the wire feeding gun to meet complex processing requirements.

[0050] This system achieves overall equipment stability through the fixed universal casters 3-1 on the working platform 3, while the working plane 3-2 on the platform serves as the support plane for workpiece processing. The entire device ensures coordination and consistency among all aspects of the processing by real-time monitoring of the laser, powder feeding, wire feeding, and electromagnetic field operation, combined with the dynamic adjustment function of the workpiece translation mechanism 4. When a deviation in the processing position or workpiece condition is detected, the control system can dynamically adjust the laser power, powder feeding amount, or wire feeding speed through feedback signals, while simultaneously optimizing the electromagnetic field parameters to guarantee high stability and accuracy in processing quality.

[0051] like Figure 7As shown, the workpiece translation mechanism 4 of this invention includes a servo motor 4-1, a ball bearing nut mounting plate 4-2, a sensing plate 4-3, three U-shaped photoelectric sensors 4-4, and a screw drive device 4-5. Based on the set speed and moving distance, the U-shaped photoelectric sensors 4-4, in conjunction with the screw drive device 4-5, achieve high-precision movement. Combined with the electromagnetic generator 2, the electromagnetic field is stabilized by the movement of the workpiece 9 while the electromagnetic field remains fixed. The workpiece clamping device 5 includes a clamping support 5-1, four adjusting fastening screws 5-2, and four workpiece pressure plates 5-3. The adjusting fastening screws 5-2 are used to adapt to workpieces of different thicknesses depending on their tightening state. The workpiece clamping device 5 is connected to an electric field power source to ensure a stable electric field is formed inside the workpiece.

[0052] The workpiece clamping device 5 further includes anti-slip pads and elastic adjusting pads to effectively prevent workpiece slippage and provide uniform pressure during clamping, avoiding damage to the workpiece surface. Its clamping support 5-1 is made of high-strength material to ensure stability under high load or high electric field environments. By adjusting the fastening screws 5-2, rapid adjustment for workpieces of different sizes, shapes, and thicknesses can be achieved. The clamping device also integrates a conductive path for connection to an electric field power supply to ensure the efficient formation of a stable electric field within the workpiece.

[0053] The working platform 3 of this invention includes a fixed universal wheel 3-1, a working plane component 3-2, and a working platform support component 3-3, which enables the entire device to flexibly change its working position and stably support the laser processing process in place. Figure 8 As shown.

[0054] This device achieves precise projection of a high-power laser beam through a laser generator 1. Its high-power laser head 1-1 is fixedly connected to the powder feeding device 6 and the wire feeding device 7 via angle bracket connectors 8. The laser generator, powder feeding device, and wire feeding device form a compact "L"-shaped structure. During laser processing, the laser head 1-1 provides a high-intensity beam to melt the material, while the powder feeding device 6 and wire feeding device 7 respectively transport metal powder and metal wire to the processing area. The powder and wire feeding paths are precisely aligned coaxially with the laser head, ensuring uniform melting of the reinforcing particles and the substrate, thus realizing laser additive manufacturing of functionally graded composite materials.

[0055] The powder feeding device 6, through a dovetail-groove two-degree-of-freedom adjustment device 6-4 and an angle bracket connector 8, enables free adjustment of the position and orientation of the powder feeding nozzle 6-1 to adapt to different workpiece shapes and processing requirements. The powder feeding nozzle 6-1 is designed with inner and outer layers. The inner layer powder outlet hole 6-5 accurately delivers metal powder through a pneumatic transmission method, while the outer layer protective air outlet hole 6-6 forms a protective airflow in a coaxial layout to prevent powder dispersion and achieve stable control of the powder feeding area, thereby improving processing accuracy and particle distribution consistency.

[0056] The wire feeding device 7 achieves flexible adjustment of three degrees of freedom through a combination of a dovetail groove type two-degree-of-freedom adjustment device 7-2 and a single-degree-of-freedom slide table 7-3. The wire feeding gun 7-1 stably delivers the metal wire to the laser processing area, and its position can be finely adjusted according to specific processing requirements. Through this precise adjustment mechanism, uniform and stable wire feeding can be achieved on the surface of workpieces with complex geometries, further improving the structural performance of composite materials.

[0057] The electromagnetic generator 2 generates a directional electromagnetic field through the coil 2-2 and the electromagnetic generating pole 2-1. Combined with the structural design of the inner partition 2-3 and the outer partition 2-9, this ensures a uniform distribution of the electromagnetic field within the processing area. By adjusting the lead screw 2-7 and the pressure cap 2-8, the direction and intensity of the electromagnetic field are dynamically controlled, thereby flexibly regulating the distribution gradient of the reinforcing particles in the functionally graded composite material. This method achieves a high degree of controllability in particle distribution through directional Lorentz force applied to the particles.

[0058] The workpiece translation mechanism 4 drives the ball nut mounting plate 4-2 and the screw transmission device 4-5 via a servo motor 4-1 to achieve high-precision movement of the workpiece 9. Simultaneously, a U-shaped photoelectric sensor 4-4 precisely monitors the movement distance and speed. This design maintains a fixed electromagnetic field while the workpiece moves, preventing electromagnetic field disturbances from causing uneven particle distribution, thus ensuring the stability of the gradient distribution of reinforcing particles and the processing quality.

[0059] The work platform 3 enables flexible movement of the entire device via fixed casters 3-1, adapting to different processing environments. During processing, the work plane 3-2 and the work platform support 3-3 provide stable support, avoiding the impact of vibration during laser processing and ensuring that the relative position of the laser head and the workpiece in the processing area remains consistent, thereby achieving high-quality manufacturing of functionally graded composite materials.

[0060] In summary, the functionally graded particle-reinforced composite laser additive manufacturing equipment proposed in this invention effectively solves the problem of difficult-to-control reinforcement particle distribution in traditional LDED technology. By using a co-feeding method, this equipment avoids the loss of reinforcement particles due to direct laser radiation, while simultaneously achieving full melting of the metal matrix, thus accommodating the performance requirements of different components in the composite material. Furthermore, the equipped electromagnetic field generator flexibly adjusts the particle distribution gradient by generating directional Lorentz forces, meeting the stringent requirements of FGM-PMMC for composition and structural gradients. Compared to traditional LDED equipment, this invention achieves a good balance between high efficiency and high performance. The co-feeding device combines the low cost of powder-feed LDED with the high material utilization rate of wire-feed LDED, and through the synergistic effect of the electromagnetic field, achieves one-time forming of functionally graded composites, eliminating cumbersome pre- and post-processing steps, significantly improving processing efficiency and reducing manufacturing costs. In addition, the 5-DOF adjustable mechanism designed for this equipment gives it a wide range of process adaptability. By adjusting the relative positions of the laser, powder and wire, the characteristics of the molten pool and the material migration behavior can be flexibly controlled. It is suitable for a variety of laser processing scenarios, including laser-arc hybrid welding, laser multi-energy field welding, laser powder feeding welding, laser cladding, laser injection and other fields.

[0061] In the field of laser-arc hybrid welding, the wire feeding device of this equipment can be used to connect an electric welding machine and a laser head to achieve laser-arc hybrid welding. In the field of laser multi-energy field welding, an electromagnetic field can be applied to the molten pool during laser welding to control weld strength and porosity. In the field of laser powder feeding welding, the powder feeding device and laser head of this equipment can be used to achieve powder feeding welding and improve joint strength.

[0062] Figure 9 The test results show that the porosity of the weld was controlled by magnetic field using this equipment during laser welding. As the magnetic field strength increased, the penetration depth tended to stabilize and the porosity decreased to a certain extent. Figure 10 The results of the electric field test when using this equipment in laser welding show that when the value is lower than this value, the weld porosity is similar to that of a single magnetic field, and when the value is higher than this value, the weld porosity decreases as the applied current density increases.

[0063] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications, equivalent substitutions, and improvements made by those skilled in the art within the scope of the technology disclosed in the present invention, and within the spirit and principles of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A laser additive manufacturing equipment for functionally graded particle-reinforced composites, characterized in that, include: Laser generator, electromagnetic generator, work platform, workpiece translation mechanism, workpiece clamping device, powder feeding device, wire feeding device; The laser generating device includes a high-power laser head, and the powder feeding device and the wire feeding device are respectively connected to the two sides of the high-power laser head through corner bracket connectors; the overall structure formed by connecting the laser generating device, the powder feeding device and the wire feeding device is "L" shaped. The powder feeding device includes a powder feeding nozzle, a powder feeding quick-connect connector, a protective gas quick-connect connector, a dovetail groove type two-degree-of-freedom adjustment device, and an angle code connector; the powder feeding device achieves two-degree-of-freedom pose adjustment through the dovetail groove type two-degree-of-freedom adjustment device. The powder feeding device has two layers: the inner layer has one powder outlet hole, which feeds powder by air; the outer layer has 10 protective air outlet holes, which are arranged coaxially with the powder outlet hole to constrain the powder action area. The wire feeding device includes a wire feeding gun, a dovetail groove two-degree-of-freedom adjustment device, a single-degree-of-freedom slide, and corner bracket connectors. The wire feeding device achieves three degrees of freedom of pose adjustment through the dovetail groove two-degree-of-freedom adjustment device and the single-degree-of-freedom slide. The powder feeding device, together with the wire feeding device, forms a five-degree-of-freedom pose adjustment capability, used to adjust the relative pose of light and wire, light and powder, and wire and powder, so that the laser output by the high-power laser head heats the metal wire fed by the wire feeding device, and the reinforcing particles fed by the powder feeding device can avoid direct laser radiation. The electromagnetic generator includes an electromagnetic pole, a coil, an inner partition, a horizontal yoke, a vertical yoke, a sleeve, a lead screw, a pressure cap, an outer partition, and a 3P terminal block. The electromagnetic generator produces a directional electromagnetic field through the coil and the electromagnetic pole. Combined with the structural design of the inner and outer partitions, it ensures that the electromagnetic field is uniformly distributed within the processing area. By adjusting the lead screw and pressure cap, the direction and intensity of the electromagnetic field are dynamically controlled. By determining the target distribution gradient of the reinforcing particles in the functionally graded particle reinforced metal matrix composite, the magnitude and direction of the electromagnetic field and the directional Lorentz force it generates can be specifically controlled. The workpiece translation mechanism includes a servo motor, a ball bearing nut mounting plate, a sensor plate, three U-shaped photoelectric sensors, and a screw drive device. Based on the set speed and moving distance, it works with the U-shaped photoelectric sensors to achieve high-precision movement through the screw drive device. In conjunction with an electromagnetic generator, it ensures electromagnetic field stability by moving the workpiece while keeping the electromagnetic field fixed. The workpiece clamping device includes a clamping support, four adjusting fastening screws, and four workpiece pressure plates. It can adapt to workpieces of different thicknesses by adjusting the different fastening states of the fastening screws.

2. The laser additive manufacturing equipment for functionally graded particle-reinforced composites as described in claim 1, characterized in that, The work platform includes fixed casters, a work surface component, and a work platform support component.

Images