Reinforcing method for 3D part

Abstract

The embodiment of the invention relates to a 3D part reinforcing method which comprises the steps that a solid structure of a 3D part is subjected to hollowing treatment, and a filling cavity with a thin-wall shell is generated; an internal supporting structure is added into the filling cavity, at least one injection opening is added to the outer wall of the filling cavity, and a 3D part model file is generated; supporting bodies of the internal supporting structure are a plurality of cylindrical bodies which are arranged at intervals and are not in contact with one another; printing a pre-filled shell of the 3D part according to the 3D part model file; filling a reinforcing material through an injection port of the pre-filling shell; and curing and shaping the filled pre-filled shell to form the 3D part comprising the pre-filled shell and the reinforcing material.

Description

Technical Field

[0001] The present invention relates to the technical field of 3D printing, and in particular to a method for strengthening 3D components. Background Art

[0002] With the wide application of 3D printing technology, its potential in the field of transportation structures such as vehicles, ships, and aerospace has become increasingly prominent. The existing method for strengthening 3D printed models is to adhere a composite material layer, such as carbon fiber reinforced polymer (CFRP), to the surface of the 3D printed model to improve strength. However, this surface adhesion method has problems such as poor adhesion and complex processes, and cannot fundamentally solve the insufficient strength of the internal structure of the model. Summary of the Invention

[0003] The object of the present invention is to address the deficiencies of the existing technology and provide a method for strengthening 3D components. By hollowing out the solid structure of the 3D component and filling the reinforcement material in combination with the internal support structure, the strength of the 3D component is strengthened; through the setting of the internal support structure, printing support is ensured, active regulation of fiber orientation is achieved, and fiber deposition is reduced.

[0004] To achieve the above object, the present invention provides a method for strengthening 3D components, including: hollowing out the solid structure of the 3D component to generate a filling cavity with a thin-walled shell;

[0005] Adding an internal support structure to the filling cavity and adding at least one injection port on the outer wall of the filling cavity to generate a 3D component model file; the support bodies of the internal support structure are a plurality of columnar bodies arranged at intervals and not in contact with each other;

[0006] Printing a pre-filled shell of the 3D component according to the 3D component model file;

[0007] Filling the reinforcement material through the injection port of the pre-filled shell;

[0008] Performing a curing and shaping process on the pre-filled shell after filling to form a 3D component including the pre-filled shell and the reinforcement material.

[0009] Furthermore, the circumferences and spacing distances of the plurality of columnar bodies are set according to the structure and strength of the 3D component.

[0010] Furthermore, the strengthening method further includes adding at least one air vent on the outer wall of the filling cavity.

[0011] Furthermore, the reinforcement material includes uniformly dispersed magnetic nanoparticles.

[0012] Furthermore, the injection port and the air vent are provided with a lockable setting.

[0013] Furthermore, the flow channels in the filled cavity have a discretized lotus node type topological structure; in the discretized lotus node type topological structure, any flow channel unit does not cross other flow channel units in three-dimensional space.

[0014] Furthermore, the ends of the flow channel units in the filled cavity adopt a NACA airfoil profile, and the curvature radius range of the NACA airfoil profile is 0.5 - 3.0 mm.

[0015] Furthermore, the height of the support body of a single flow channel is 0.8 - 1.2 times the average fiber length of the reinforcing material.

[0016] Furthermore, the distance between adjacent flow channel units is not less than the sum of three times the fiber diameter of the reinforcing material and the safety distance, where the safety distance range is 0.5 - 2.0 mm.

[0017] Furthermore, the cross - angle deviation between adjacent flow channel units in three - dimensional space is not less than 15 degrees.

[0018] Furthermore, the cross - section of the flow channel in the filled cavity changes periodically along the flow direction; the scaling ratio range of the flow channel cross - section is 1:1.5 - 1:3.

[0019] Furthermore, filling the reinforcing material through the injection port of the pre - filled shell specifically includes filling the reinforcing material into the injection port by means of pulsed injection; wherein, the pulse frequency range is 1 - 5 Hz, and the amplitude range is 0.2 - 0.8 MPa.

[0020] Furthermore, printing the pre - filled shell of the 3D component according to the 3D component model file is specifically printing the pre - filled shell of the 3D component by the FDM process according to the 3D component model file; wherein, the support angle range of the support body is 30 - 60 degrees, the compression modulus range is 300 - 800 MPa, and the critical collapse stress is not less than twice the square of the ratio of the support body thickness to the overhang span multiplied by the compression modulus.

[0021] Furthermore, the thin - walled shell is made of a soluble or thermally degradable material, the wall thickness of the thin - walled shell is distributed in a periodic gradient, and the wall thickness range is 0.2 - 0.8 mm.

[0022] Furthermore, the filling environment for filling the reinforcing material through the injection port of the pre - filled shell is a vacuum environment.

[0023] Furthermore, the mode of the hollowing - out treatment includes a thin - walled hollowing - out replacement mode; the thin - walled hollowing - out replacement mode is to perform lightweight reconstruction on the 3D component solid model based on finite element analysis to generate a filled cavity with a thin - walled shell.

[0024] Further, the hollowing treatment mode further includes a housing replacement mode; the housing replacement mode is to generate an outward offset housing by offsetting a preset distance outward based on the outer surface contour of the basic model of the 3D component; perform a Boolean subtraction operation on the outward offset housing and the basic model of the 3D component to generate a filled cavity with a thin-walled housing.

[0025] Further, the ratio range of the average thermal expansion coefficient of the reinforcing material to the average thermal expansion coefficient of the support is [1.03, 1.07].

[0026] Further, the reinforcement method further includes generating a programmable magnetic field through an external permanent magnet array for directionally regulating the fiber orientation in the reinforcing material.

[0027] Further, the directional regulation of the fiber orientation in the reinforcing material is specifically:

[0028] When the reinforcing material is in the pressure-holding stage in the pre-filled housing, start the pulsed magnetic field of the programmable magnetic field to directionally regulate the fiber orientation in the reinforcing material;

[0029] When the reinforcing material is in the curing stage in the pre-filled housing, start the steady magnetic field of the programmable magnetic field to lock the fiber orientation state.

[0030] Further, the pulsed magnetic field of the programmable magnetic field is a pulsed gradient magnetic field, where the pulsed gradient magnetic field is to synchronously program the gradient magnetic field and the pulsed magnetic field parameters; the steady magnetic field of the programmable magnetic field is a gradient magnetic field.

[0031] Further, the particle size range of the magnetic nanoparticles is 20 - 50 nm, the surface is modified with a silane coupling agent, and the addition amount in the reinforcing material is 2 - 5 vol%.

[0032] A reinforcement method for a 3D component provided by an embodiment of the present invention realizes the strength reinforcement of the 3D component by hollowing out the solid structure of the 3D component and filling the reinforcing material in combination with an internal support structure; through the setting of the internal support structure, the printing support is ensured, the active regulation of the fiber orientation is realized, and the fiber deposition is reduced. Description of the Drawings

[0033] Figure 1 It is one of the flowcharts of the reinforcement method for a 3D component provided by an embodiment of the present invention;

[0034] Figure 2 It is another flowchart of the reinforcement method for a 3D component provided by an embodiment of the present invention;

[0035] Figure 3 It is a schematic diagram of the hollowing of a 3D component in the reinforcement method for a 3D component provided by an embodiment of the present invention;

[0036] Figure 4 Schematic diagram of a 3D component adding an internal support structure to the filling cavity of the reinforcement method for 3D components provided by an embodiment of the present invention. Detailed implementation manners

[0037] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0038] The technical solutions of the present invention will be further described in detail below through the accompanying drawings and embodiments.

[0039] A reinforcement method for 3D components provided by an embodiment of the present invention applies 3D printing technology to fields such as aerospace, medical and health, new energy vehicles, renewable energy, and industrial equipment and high-end equipment. By hollowing out the solid structure of the 3D component and combining it with an internal support structure for filling reinforcement materials, the strength reinforcement of the 3D component is achieved; through the setting of the internal support structure, printing support is ensured, active regulation of fiber orientation is achieved, and fiber deposition is reduced; uniformly dispersed magnetic nanoparticles are added to the original reinforcement materials, and combined with a programmable magnetic field, precise fiber orientation control is achieved; through modular magnetic pole design, the magnetic field direction is differentially regulated within a small control unit to make the local anisotropy ratio adjustable within a certain range, accurately matching the multi-directional load requirements of complex components.

[0040] Figure 1 One of the flowcharts of the reinforcement method for 3D components provided by an embodiment of the present invention, as Figure 1 shown, the reinforcement method for 3D components includes:

[0041] Step 110, hollow out the solid structure of the 3D component to generate a filling cavity with a thin-walled shell. Optionally, the thin-walled shell is made of a soluble or thermally degradable material.

[0042] Specifically, a basic model of the 3D component is constructed through design software, and the solid structure of the basic model is hollowed out to form a filling cavity with a thin-walled shell. The flow channel surface of the thin-walled shell is a periodic micron-scale groove structure, such as stripes or grid structures parallel to the flow direction, and the surface roughness ranges from 0.1 to 0.5 μm. Through the periodic micron-scale groove structure, the rotation of fibers is suppressed by the fluid boundary layer effect, so that the fibers can still maintain a stable orientation state after flowing out of the flow channel, and the relaxation time is extended by 3-5 times.

[0043] In a possible implementation, the hollowing treatment mode is a thin-walled hollow replacement mode; the thin-walled hollow replacement mode is to perform lightweight reconstruction on the 3D component solid model based on finite element analysis to generate a filled cavity with a thin-walled shell. Optionally, the wall thickness of the thin-walled shell is periodically gradient-distributed, and the wall thickness range is 0.2 - 0.8 mm. The periodic gradient distribution within this wall thickness range can ensure that the bending modulus of the thin-walled shell is not less than 500 MPa and the tensile strength is not greater than 5 MPa. This tensile strength is only 1 / 50 of the strength of the final formed material. The high bending modulus makes the thin-walled shell not easily bend under stress, ensuring structural stability, and the low tensile strength ensures that it can be easily removed by mechanical peeling, dissolution, or thermal degradation after curing is completed, avoiding residual effects on the performance of the final component.

[0044] In a possible implementation, the hollowing treatment mode is an outer shell replacement mode; the outer shell replacement mode is to generate an outer offset shell by offsetting a preset distance outward based on the outer surface contour of the basic model of the 3D component; perform a Boolean subtraction operation on the outer offset shell and the basic model of the 3D component to generate a filled cavity with a thin-walled shell. Optionally, the preset distance range is 0.2 - 0.5 mm.

[0045] Step 120, add an internal support structure to the filled cavity and add at least one injection port on the outer wall of the filled cavity to generate a 3D component model file; the support bodies of the internal support structure are multiple columnar bodies arranged at intervals and not in contact with each other. Optionally, the ratio range of the average thermal expansion coefficient of the reinforcement material to the average thermal expansion coefficient of the support body is [1.03, 1.07]. Within this expansion coefficient range, it can be ensured that the dimensional deviation after dissolution is not greater than 0.1%.

[0046] Among them, one or more injection ports can be added to the outer wall of the filled cavity. Optionally, the injection port and the air exhaust port share one port, or at least one air exhaust port is added to the outer wall of the filled cavity. Further optionally, the injection port and the air exhaust port are set to be lockable and removed by cutting and grinding after curing and shaping.

[0047] Among them, the perimeter and spacing distance of the multiple columnar bodies are set according to the structure and strength of the 3D component; the columnar body can be a cylinder, a prism, an elliptical cylinder, or other polygonal columns. Preferably, the columnar body is a cylinder. When the reinforcement material is a resin containing short carbon fiber, the fiber length range is 0.2 - 10.0 mm, and the aspect ratio range is 50 - 2000. When flowing through the filled cavity, the internal support body actively regulates the fiber orientation through the shear stress orientation effect and the normal stress difference strengthening. Among them, the shear stress orientation effect is that a high shear rate (γ = 100 - 500 s -1), inducing the long axis of the fiber to align along the streamline direction, which conforms to the Jeffery orbit theory; the normal stress difference is enhanced to the second normal stress difference generated in the flow channel expansion region (the expansion angle ranges from 5° to 15°) (N2 = η·γ -2 ·λ, where λ is the fluid relaxation time, γ is the shear rate, and η is the viscosity of the fluid) forcing the fiber towards the center plane of the flow channel, forming a gradient distribution in the thickness direction.

[0048] Among them, the flow channel in the filled cavity has a discretized coupled-node topological structure. The discretized coupled-node topological structure is such that any flow channel unit does not cross other flow channel units in three-dimensional space. Optionally, the cross-angle deviation between adjacent flow channel units in three-dimensional space is not less than 15 degrees to ensure the uniqueness of the fiber flow path. Optionally, the height of the support body of a single flow channel is 0.8 to 1.2 times the average length of the fibers of the reinforcing material to ensure that the fibers can pass through the unit completely without being intercepted. Further optionally, the distance between adjacent flow channel units is not less than the sum of three times the fiber diameter of the reinforcing material and the safety distance, where the safety distance ranges from 0.5 to 2.0 mm. Through computational fluid dynamics verification, this distance can eliminate the recirculation vortex, and the vorticity is less than 0.1 s -1 .

[0049] Among them, the end of the flow channel unit in the filled cavity adopts the NACA (National Aeronautics and Space Administration) airfoil profile. Optionally, the radius of curvature of the airfoil profile ranges from 0.5 to 3.0 mm, and this range makes the velocity gradient of the outflow fluid not greater than 50 s -1 to avoid the accumulation of fibers due to sudden velocity changes.

[0050] Among them, the cross-section of the flow channel in the filled cavity changes periodically along the flow direction. The periodically changing flow channel cross-section causes changes in flow velocity and pressure (△P = 0.5ρ(v2 2 -v1 2 ), where ρ is the fluid density, and v1 and v2 are the flow velocities of the fluid at cross-section 1 and cross-section 2 respectively), thereby accelerating the fiber arrangement and avoiding fiber agglomeration caused by sudden changes in flow velocity. Optionally, the scaling ratio of the flow channel cross-section ranges from 1:1.5 to 1:3.

[0051] Among them, multiple support body structures serve as the mechanical support for the suspended part. Optionally, the support angle of the support body ranges from 30 to 60 degrees, the compression modulus ranges from 300 to 800 MPa, and the critical collapse stress is not less than twice the square of the ratio of the compression modulus multiplied by the thickness of the support body to the suspended span, that is, σ_cr≥2E_c(t / L)2, where σ_cr is the critical collapse stress, E_c is the compression modulus, t is the thickness of the support body, and L is the suspended span.

[0052] In a specific simulation experiment, a multi-field coupling model of the fluid field, solid field, and fiber field is established through finite element analysis. The generated simulation result verification indexes are that the fiber orientation angle deviation is not greater than 8°, the deviation of the traditional process is not less than 25°, the fiber volume fraction at the runner intersection is not greater than 5%, the traditional structure is not less than 22%, and the deformation of the printed support structure is not greater than 0.1 mm / m, meeting the FDM layer thickness accuracy requirements.

[0053] In a specific example, Figure 3 Schematic diagram of hollowing of the 3D component for the reinforcement method of the 3D component provided in the embodiment of the present invention; Figure 4 Schematic diagram of the 3D component with an internal support structure added to the filling cavity for the reinforcement method of the 3D component provided in the embodiment of the present invention, combined with Figure 3 and Figure 4 , including a thin-walled shell 1, a filling cavity 2, a support body 3, and an injection port 4. It should be noted that Figure 3 and Figure 4 are 3D components with different structures and complexities.

[0054] Step 130, printing a pre-filled shell of the 3D component according to the 3D component model file.

[0055] Specifically, the pre-filled shell of the 3D component is printed by the Fused Deposition Modeling (FDM) process according to the 3D component model file. It should be noted that the dimensional parameter values involved in step 120 do not retain the engineering implementation elasticity. In actual application, the engineering implementation elasticity needs to be retained. Optionally, the engineering implementation elasticity is 0.5 - 3.0 mm.

[0056] Step 140, filling the reinforcement material through the injection port of the pre-filled shell.

[0057] Among them, the reinforcement material includes one or more of materials such as carbon fiber resin, ceramic resin, a mixture of metal powder and liquid, or plasticized plastic. Here, it should be noted that the experimental data and application data involved in this embodiment regarding the reinforcement material parameters are based on the carbon fiber resin and the support body being cylindrical.

[0058] Among them, filling the reinforcement material through the injection port of the pre-filled shell specifically includes filling the reinforcement material into the injection port by a pulsed injection method. Optionally, the pulse frequency range is 1 - 5 Hz, and the amplitude range is 0.2 - 0.8 Mpa. Under this pulse frequency and amplitude range, a periodic peeling effect is generated on the boundary layer of the runner wall surface, making the residence time of the adhering fibers less than 0.1 s.

[0059] Among them, the filling environment for filling the reinforcement material through the injection port of the pre-filled shell is a vacuum environment. In a specific example, at a vacuum degree ≤ 103 Under Pa environment, the viscosity η of the carbon fiber resin is 0.5 - 2.0 Pa·s, and it infiltrates between pre-filled shells under the drive of a pressure difference ΔP = 0.5 - 1.2 MPa, where the permeability coefficient K = 10 -12 -10 -10 m 2 , achieving a gap filling rate ≥ 98%. When the carbon fiber resin cures, it undergoes an ester exchange reaction with the pre-filled shell to form a covalent bond network. The interfacial shear strength is not less than 15 MPa and can reach 45 - 60 MPa. Microscopic characterization shows that the thickness range of the interfacial transition zone is 50 - 200 nm, achieving molecular-level bonding.

[0060] In a possible implementation, the reinforcing material further includes uniformly dispersed magnetic nanoparticles. The magnetic nanoparticles can be Fe3O4, etc. Adding the magnetic nanoparticles to the original reinforcing material forms a composite material. For example, adding magnetic nanoparticles to the carbon fiber resin can form a magnetic-fiber composite. Optionally, the particle size range of the magnetic nanoparticles is 20 - 50 nm, and the surface is modified with a silane coupling agent to ensure good compatibility with the resin. The addition amount in the reinforcing material is 2 - 5 vol%, so as to form a continuous magnetic response network without affecting the resin fluidity.

[0061] In the step 140, in a possible implementation, it specifically includes step A1:

[0062] Step A1, generating a programmable magnetic field through an external permanent magnet array for directionally regulating the fiber orientation in the reinforcing material.

[0063] Specifically, a Halbach array is constructed using permanent magnets. Optionally, the permanent magnet is samarium cobalt Sm2Co 17 , and it still maintains a magnetic field strength ≥ 0.8 T at a high temperature of 150 °C.

[0064] Among them, the programmable magnetic field is a differential magnetic field. By adjusting the magnetic pole angle through modular magnetic pole design, a differential magnetic field is formed in different regions of the same component to achieve precise matching between the local fiber orientation and the principal stress direction at the corresponding position, and the deviation angle is controlled within ≤ 8°. Optionally, the minimum control unit is 5×5×5 mm 3 and the modular unit size is 10×10×10 mm 3 .

[0065] Among them, directionally regulating the fiber orientation in the reinforcing material specifically means:

[0066] In the injection stage, turn off the magnetic field to avoid interfering with the resin flow, and maintain the resin temperature at 40 - 60 °C to ensure the initial uniform distribution of the fibers.

[0067] When the reinforcing material is in the pressure-holding stage in the pre-filled shell, that is, when the temperature is raised to 60 - 80 °C, the resin viscosity is reduced to 0.5 - 2.0 Pa·s, and the fiber freedom of movement is enhanced, the pulse magnetic field of the programmable magnetic field is activated to directionally regulate the fiber orientation in the reinforcing material. Among them, the pulse magnetic field of the programmable magnetic field is a pulsed gradient magnetic field, and the pulsed gradient magnetic field synchronously programs the gradient magnetic field and the pulse magnetic field parameters. The optional range of the pulse frequency is 1 - 10 Hz, and the gradient magnetic field range is 1 - 5 T / m.

[0068] When the reinforcing material is in the curing stage in the pre-filled shell, that is, when the temperature is raised to 80 - 120 °C and the resin viscosity rises and gradually cures to 60 - 80%, the steady magnetic field of the programmable magnetic field is activated to lock the fiber orientation state. The steady magnetic field of the programmable magnetic field is a gradient magnetic field.

[0069] In a specific application example, the 3D component is a drone wing bracket, a radial orientation (E∥ = 58 GPa) is formed in the wing root area, a gradient orientation (E∥ / E⊥ transitions from 3:1 to 1:1) is set in the wing tip transition area, the fatigue life is increased from 20,000 times to 150,000 times, and while the weight is reduced by 12%, the load-bearing capacity is increased by 40%.

[0070] Step 150, perform a curing and shaping process on the pre-filled shell after filling to form a 3D component including the pre-filled shell and the reinforcing material.

[0071] Specifically, send the pre-filled shell after filling into a heating box, and perform curing, melting or sintering treatment according to the characteristics of the reinforcing material to achieve the final shaping.

[0072] In a possible implementation manner, the pre-filled shell and the reinforcing material are cured and retained together.

[0073] In another possible implementation manner, a water-soluble material is used to print the pre-filled shell, and after curing, the internal model is retained by water dissolution, or a thermodegradable material is used to print the pre-filled shell, and high-temperature sintering is performed to degrade and volatilize the surface material.

[0074] In an alternative solution, Figure 2 This is the second flowchart of the 3D component reinforcement method provided by the embodiment of the present invention. As Figure 2 shown, the reinforcement method further includes:

[0075] Step 160, remove the injection port and the air vent on the cured 3D component.

[0076] Specifically, when the injection port and the air vent are of a locking design and the inlet and outlet protrude from the component surface, use cutting and grinding tools to remove their protruding parts and restore the external shape of the 3D component.

[0077] In a possible implementation, the 3D components with cleared ports are subjected to surface spraying treatment to enhance appearance and durability.

[0078] Those skilled in the art should further realize that the units and algorithm steps of the examples described in combination with the embodiments disclosed herein can be implemented by electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the composition and steps of the examples have been generally described according to functions in the above description. Whether these functions are executed in a hardware or software manner depends on the specific application and design constraints of the technical solution. Skilled professionals can use different methods for each specific application to implement the described functions, but such implementation should not be considered to exceed the scope of the present invention.

[0079] The steps of the methods or algorithms described in combination with the embodiments disclosed herein can be implemented by hardware, software modules executed by a processor, or a combination of both. The software modules can be placed in a random access memory (RAM), memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art.

[0080] The specific implementation manners described above further elaborate on the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only the specific implementation manners of the present invention and is not used to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for reinforcing a 3D component, characterized in that: The reinforcement method comprises: Hollow out the solid structure of the 3D part to generate a filled cavity with a thin-walled shell; An internal support structure is added to the filling cavity, and at least one injection port is added to the outer wall of the filling cavity to generate a 3D component model file; the support body of the internal support structure is a plurality of cylindrical bodies arranged at intervals and not in contact with each other; Printing a pre-filled shell of a 3D component according to the 3D component model file; Filling the reinforcing material through the injection port of the pre-filled shell; The filled pre-filled shell is cured and shaped to form a 3D component including the pre-filled shell and the reinforcement material.

2. The reinforcement method according to claim 1, characterized in that: The circumferences and spacing distances of the plurality of columnar bodies are set according to the structure and strength of the 3D component.

3. The reinforcement method according to claim 1, characterized in that: The reinforcement method also includes adding at least one air vent on an outer wall of the filling cavity.

4. The reinforcement method according to claim 1, characterized in that: The reinforcing material includes uniformly dispersed magnetic nanoparticles.

5. The reinforcement method according to claim 3, characterized in that: The injection port and the air exhaust port are lockable.

6. The reinforcement method according to claim 1, characterized in that: The flow channel in the filling cavity is a discretized lotus-root-node topological structure; the discretized lotus-root-node topological structure means that any flow channel unit does not intersect with other flow channel units in three-dimensional space.

7. The reinforcement method according to claim 1, characterized in that: The end of the flow channel unit in the filling cavity adopts a NACA airfoil profile, and the curvature radius of the NACA airfoil profile ranges from 0.5 to 3.0 mm.

8. The reinforcement method according to claim 6, characterized in that: The height of the support body of a single flow channel is 0.8 to 1.2 times the average length of the fibers of the reinforcing material.

9. The reinforcement method according to claim 6, characterized in that: The spacing between adjacent flow channel units is not less than the sum of three times the fiber diameter of the reinforcement material and the safety distance, wherein the safety distance ranges from 0.5 to 2.0 mm.

10. The reinforcement method according to claim 6, characterized in that: The intersection angle deviation between adjacent flow channel units in three-dimensional space is not less than 15 degrees.

11. The reinforcement method according to claim 1, characterized in that: The flow channel cross section in the filling cavity changes periodically along the flow direction; the scaling ratio of the flow channel cross section ranges from 1:1.5 to 1:

3.

12. The reinforcement method according to claim 1, characterized in that: The filling of the reinforcing material through the injection port of the pre-filled shell specifically includes filling the reinforcing material into the injection port by pulse injection; wherein the pulse frequency range is 1 to 5 Hz, and the amplitude range is 0.2 to 0.8 MPa.

13. The reinforcement method according to claim 1, characterized in that: Printing a pre-filled shell of a 3D component according to the 3D component model file, specifically printing a pre-filled shell of a 3D component according to the 3D component model file through an FDM process; wherein the support angle range of the support body is 30-60 degrees, the compression modulus range is 300-800MPa, and the critical collapse stress is not less than twice the compression modulus multiplied by the square of the ratio of the support body thickness to the suspended span.

14. The reinforcement method according to claim 1, characterized in that: The thin-walled shell is made of a soluble or thermally degradable material, and the wall thickness of the thin-walled shell is distributed in a periodic gradient, with a wall thickness range of 0.2-0.8 mm.

15. The reinforcement method according to claim 1, characterized in that: The filling environment for filling the reinforcement material through the injection port of the pre-filling shell is a vacuum environment.

16. The reinforcement method according to claim 1, characterized in that: The hollowing treatment mode includes a thin-wall hollowing replacement mode; the thin-wall hollowing replacement mode is to perform lightweight reconstruction on the 3D component solid model based on finite element analysis to generate a filling cavity with a thin-wall shell.

17. The reinforcement method according to claim 1, characterized in that: The hollowing treatment mode also includes an outer shell replacement mode; the outer shell replacement mode is based on the outer surface contour of the basic model of the 3D component, and is offset outward by a preset distance to generate an outer shell; The outer eccentric shell is subjected to a Boolean subtraction operation from the base model of the 3D component to generate a filled cavity with a thin-walled shell.

18. The reinforcement method according to claim 1, characterized in that: The ratio of the average thermal expansion coefficient of the reinforcing material to the average thermal expansion coefficient of the supporting body is in the range of [1.03, 1.07].

19. The reinforcement method according to claim 4, characterized in that: The reinforcement method also includes generating a programmable magnetic field through an external permanent magnetic array to directionally control the fiber orientation in the reinforcement material.

20. The reinforcement method according to claim 19, characterized in that: The directional control of the fiber orientation in the reinforcement material is specifically as follows: When the reinforcement material is in a pressure-holding stage in the pre-filled shell, starting a pulse magnetic field of a programmable magnetic field to directionally regulate the fiber orientation in the reinforcement material; When the reinforcement material is in the curing stage in the pre-filled shell, the steady-state magnetic field of the programmable magnetic field is activated to lock the fiber orientation state.

21. The reinforcement method according to claim 20, characterized in that: The pulse magnetic field of the programmable magnetic field is a pulse gradient magnetic field, wherein the pulse gradient magnetic field is a synchronous programming of the gradient magnetic field and the pulse magnetic field parameters; the steady-state magnetic field of the programmable magnetic field is a gradient magnetic field.

22. The reinforcement method according to claim 4, characterized in that: The particle size of the magnetic nanoparticles is in the range of 20 to 50 nm, the surface of the magnetic nanoparticles is modified by a silane coupling agent, and the amount of the magnetic nanoparticles added to the reinforcing material is 2 to 5 vol%.

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