Lattice structure of bionic sea urchin mouthpart-Arimastodes lantern and design method and application of lattice structure of bionic sea urchin mouthpart-Arimastodes lantern

Abstract

The invention discloses a dot matrix structure of a bionic sea urchin mouthpart, namely an Arimastodes lantern, and a design method and application of the dot matrix structure. The bionic lattice structure has good designability and manufacturability, starting from the bionic concept, the structural and morphological characteristics of the sea urchin mouthpart serve as design elements, the design elements are matched, and regulation and control of local characteristics such as the bionic unit beam diameter, the panel (curved surface) thickness, the unit size and the porosity serve as a design scheme. The stress state and fracture failure characteristics of the lattice structure are effectively improved, and the mechanical properties and functional characteristics such as compressive strength, energy absorption performance, deformation resistance, service life and deformation recovery capacity of the lattice structure are optimized. The bionic lattice structure is prepared by adopting an additive manufacturing technology. The invention is expected to play a huge role in the fields of light-weight energy-absorbing structural members, orthopedic implants, dot matrix radiators and the like.

Description

Technical Field

[0001] The present invention belongs to the technical field of additive manufacturing and bionics, and specifically relates to a lattice structure of a bionic sea urchin mouthpart - Aristotle's lantern, a design method thereof, and an application thereof. Background Art

[0002] A lattice structure is an array structure formed by the periodic arrangement of basic units in a three-dimensional space, and has excellent mechanical properties and functional characteristics such as low density, high specific strength, high energy absorption rate, and high heat dissipation rate. As a new type of metamaterial, it has currently been applied in fields such as biomedicine, communication, energy, aerospace, construction engineering, and intelligent robots.

[0003] According to the unit type, it can be divided into lattice structures based on panels, beams, curved surfaces, bionic unit structures, etc. Its manufacturability, mechanical properties, and functional characteristics not only depend on the raw materials and preparation processes, but also largely depend on the type of basic unit of the lattice structure. For example, the lattice structure based on panels has good energy absorption performance and a large specific surface area, but poor connectivity; the lattice structure based on beams has better connectivity, but is prone to stress concentration at the nodes and has poor energy absorption performance under large deformations; the uniform lattice structure based on curved surfaces has better heat dissipation performance, deformation ability, and energy absorption performance, especially its gradient structure has better energy absorption ability; the lattice structure based on bionic structures is more likely to meet the requirements of special service environments. In order to further optimize the adaptability of lattice structures under extreme conditions and give full play to their unique advantages, it is of great scientific and engineering significance to develop and design high-performance lattice structures for multi-scenarios.

[0004] Through continuous evolution, organisms have better survival and environmental adaptation abilities. Bionics provides sufficient inspiration and design basis for lattice structure design, and many novel bionic structures have emerged. For example, the bionic bamboo structure has certain impact resistance; the exoskeletons of bionic crustaceans (mantis shrimp, crab claws) have good rigidity and energy absorption characteristics; the bionic honeycomb structure has good load-bearing capacity and saves materials; the bionic beetle forewing structure has the advantages of small mass and high toughness. The mouthpart of a sea urchin - Aristotle's lantern is a unique biological structure, composed of beam-shaped teeth and planar bone plates (gnathal plates, gnathal bones), showing pentaradial symmetry, and playing a chewing role through the traction of muscles, showing excellent mechanical properties and being able to crush shells and stones. Bionics provides an effective strategy for designing lattice structures to optimize their performance under extreme conditions.

[0005] Compared with traditional processes such as machining, direct foaming, and hot isostatic pressing, additive manufacturing technology can prepare high-porosity lattice structures with highly controllable pore sizes and morphologies, stable mechanical properties, and good connectivity, and has great potential in the field of lattice structure technology. Summary of the Invention

[0006] To solve the drawbacks and deficiencies of the prior art, the primary object of the present invention is to provide a design method for the lattice structure of a bionic sea urchin mouthpart - Aristotle's lantern, providing an effective approach for the design and optimization of high-performance lattice structures.

[0007] Another object of the present invention is to provide a lattice structure of a bionic sea urchin mouthpart - Aristotle's lantern obtained by the above method.

[0008] A further object of the present invention is to provide the application of the above lattice structure of a bionic sea urchin mouthpart - Aristotle's lantern, broadening the application of bionic lattice structures in lightweight energy absorption, lightweight compression resistance, lightweight bending resistance, and lightweight heat dissipation structural components.

[0009] The object of the present invention is achieved by the following technical solutions:

[0010] A design method for the lattice structure of a bionic sea urchin mouthpart - Aristotle's lantern, comprising the following steps:

[0011] Step 1: Extract the design elements of beams and surfaces according to the external morphology and internal structural characteristics of the sea urchin mouthpart - Aristotle's lantern, design lattice units based on panels and surfaces and lattice units based on beams through 3D modeling software, and establish the relevant parameter ranges for each lattice unit;

[0012] Step 2: Transform the design elements into actual design schemes from the perspective of bionics, and combine the lattice units based on panels and surfaces and the lattice units based on beams by Boolean summation operation; optimize and analyze the design schemes from the aspects of structure and function, and adjust the local characteristics of the combined units such as beam diameter, panel (surface) thickness, unit size, porosity, etc., thereby obtaining bionic lattice units;

[0013] Step 3: Periodically array the bionic lattice units, connect the endpoints of the bionic lattice units, and obtain a bionic lattice structure with excellent functional characteristics such as mechanical properties, energy absorption characteristics, and deformation recovery.

[0014] Preferably, the types of lattice units based on panels in Step 1 include: triangular honeycomb, hexagonal honeycomb, concave-angle honeycomb, square honeycomb, face-centered cubic foam, body-centered cubic foam, simple cubic foam; the lattice unit size is 1 - 20 mm, the panel thickness is 5 - 70% of the unit size, and the lattice unit porosity is 10 - 95%; more preferably, the type of lattice unit based on panels is a rotating square honeycomb; the lattice unit size is 4 mm, the panel thickness is 16% of the unit size, and the lattice unit porosity is 59%.

[0015] Preferably, the lattice unit types based on surfaces in Step 1 include: Primitive, Diamond, Gyroid, Neovius, and Lidinoid of triply periodic minimal surfaces; the lattice unit size is 1-20 mm, the surface thickness is 5-70% of the unit size, and the lattice unit porosity is 10-95%; more preferably, the lattice unit type based on surfaces is one of Primitive triply periodic minimal surface, Diamond triply periodic minimal surface, and Gyroid triply periodic minimal surface; the lattice unit size is 2-4 mm, the surface thickness is 6-30% of the unit size, and the lattice unit porosity is 30-82%.

[0016] Preferably, the lattice unit types based on beams in Step 1 include: octahedron, cube, body-centered cubic, face-centered cubic, dodecahedron, diamond, truncated octahedron, octahedron + cube, body-centered cubic + face-centered cubic, octahedron + face-centered cubic; the lattice unit size is 1-20 mm, the diameter of the beam is 5-70% of the unit size, and the lattice unit porosity is 10-95%; more preferably, the lattice unit type based on beams is one of body-centered cubic, truncated octahedron, octahedron + face-centered cubic, face-centered cubic, and dodecahedron; the lattice unit size is 2-4 mm, the diameter of the beam is 9-20% of the unit size, and the lattice unit porosity is 70-95%.

[0017] The local features in Step 2 are at least one of the beam diameter, panel thickness, surface thickness, unit size, and porosity.

[0018] Preferably, the porosity of the bionic lattice unit in Step 2 is 10-95%, more preferably 23-80%; the bionic lattice unit size and local feature parameters are the same as those of the lattice unit in Step 1.

[0019] Preferably, the porosity of the bionic lattice structure in Step 3 is 10-95%; more preferably 23-80%.

[0020] Preferably, the number of periodic arrays in Step 3 is 2×2×2-20×20×20; more preferably 4×4×4-10×3×2.

[0021] Preferably, the 3D modeling software in Step 1 is at least one of Solid Works, UG, Rhino grasshopper, Materialise Magics, nTopology, 3ds Max, Autodesk Maya, and MATLAB.

[0022] Preferably, the specific geometric parameters, structural features, and array quantity of the bionic lattice structure described in Step 3 depend on the size and performance requirements of lightweight energy absorption, lightweight compression resistance, lightweight bending resistance, and lightweight heat dissipation components.

[0023] The present invention also provides a lattice structure of a bionic sea urchin mouthpart - Aristotle's lantern obtained by the above design method.

[0024] The present invention also provides an application of the above lattice structure of a bionic sea urchin mouthpart - Aristotle's lantern.

[0025] Preferably, the application includes applications in the preparation of lightweight energy absorption, lightweight compression resistance, lightweight bending resistance, and lightweight heat dissipation structural components, and the fields involved include at least one of biomedical devices, automobiles, ships, communications, energy, aerospace, construction engineering, and intelligent robots.

[0026] More preferably, it is applied in the preparation of lightweight energy absorption structural components, orthopedic implants, and lightweight heat dissipation structural components.

[0027] The present invention also provides a preparation method of a structural component having the above bionic lattice structure, including the following steps:

[0028] Prepare a structural component with a bionic lattice structure by using the above bionic lattice structure through additive manufacturing technology.

[0029] Preferably, the additive manufacturing technology is at least one of laser powder bed fusion, electron beam powder bed fusion, laser directed energy deposition, arc additive manufacturing, binder jetting, material extrusion, and stereolithography; more preferably, it is laser powder bed fusion technology, and its process parameters are: laser power is 65 - 300 W, scanning speed is 350 - 2400 mm / s, spot diameter is 70 - 85 μm, scanning spacing is 60 - 100 μm, layer thickness is 30 - 45 μm, and the printing strategy is to rotate the laser path by 60 - 80° every other layer.

[0030] The raw materials used in the additive manufacturing technology include at least one of metals, polymers, ceramics, or their composites; more preferably, it is NiTi alloy powder.

[0031] The present invention also provides a structural component having a bionic lattice structure obtained by the above preparation method.

[0032] The present invention also provides an application of the above structural component having a bionic lattice structure in the fields of biomedical device preparation, automobiles, ships, communications, energy, aerospace, construction engineering, and intelligent robots.

[0033] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0034] The lattice structure of a bionic sea urchin mouthpart - Aristotle's lantern proposed by the present invention has good designability and manufacturability. By combining beam elements and surface elements and regulating local characteristics such as the diameter of the bionic unit beam, the thickness of the panel (curved surface), the unit size, and the porosity, the stress state and fracture failure characteristics of the lattice structure can be effectively improved, and its mechanical properties and functional characteristics, such as compressive strength, energy absorption performance, anti-deformation ability, service life, and deformation recovery ability, can be optimized. It has great application potential in the fields of lightweight energy-absorbing structural components, orthopedic implants, lattice radiators, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a schematic diagram of the design process of the lattice structure of a bionic sea urchin mouthpart - Aristotle's lantern.

[0036] Figure 2 It is a bionic lattice structure model of Example 1 of the present invention.

[0037] Figure 3 It is a physical diagram of the bionic lattice structure of Example 1 of the present invention.

[0038] Figure 4 It is a performance diagram of the bionic lattice structure of Example 1 of the present invention.

[0039] Figure 5 It is a bionic lattice structure model of Example 2 of the present invention.

[0040] Figure 6 It is a physical diagram of the bionic lattice structure of Example 2 of the present invention.

[0041] Figure 7 It is a performance diagram of the bionic lattice structure of Example 2 of the present invention.

[0042] Figure 8 It is a bionic lattice structure model of Example 3 of the present invention.

[0043] Figure 9 It is a physical diagram of the bionic lattice structure of Example 3 of the present invention.

[0044] Figure 10 It is a performance diagram of the bionic lattice structure of Example 3 of the present invention.

[0045] Figure 11 It is a model diagram of the bionic lattice structure of Example 4 of the present invention.

[0046] Figure 12 It is a model diagram of the bionic lattice structures of Examples 5 and 6 of the present invention.

[0047] Figure 13 It is a model diagram of the lattice structure of Comparative Example 1 of the present invention.

[0048] Figure 14Physical diagram of the lattice structure of Comparative Example 1 of the present invention.

[0049] Figure 15 Performance diagram of the lattice structure of Comparative Example 1 of the present invention. Detailed implementation manners

[0050] The present invention will be further described in detail below in conjunction with embodiments and the accompanying drawings, but the implementation manners of the present invention are not limited thereto.

[0051] In the embodiments of the present invention, those not specified under specific conditions are carried out according to conventional conditions or conditions recommended by the manufacturer. Raw materials, reagents, etc. that are not specified by the manufacturer can all be obtained as conventional products through commercial purchase.

[0052] Embodiment 1

[0053] Step 1: Design of the lattice structure of a bionic sea urchin mouthpart - Aristotle's lantern

[0054] Extract key beam-like and curved design elements according to the external morphology and internal structure of the sea urchin mouthpart, and design a body-centered cubic lattice unit based on the beam, with a unit size of 3×3×3 mm 3 , the beam rod diameter is 458 μm, and the unit porosity is 90%; design a Primitive triply periodic minimal surface lattice unit based on the curved surface, with a unit size of 3×3×3 mm 3 , the curved surface thickness is 175 μm, and the unit porosity is 80%.

[0055] Furthermore, combine the body-centered cubic lattice unit and the Primitive triply periodic minimal surface lattice unit by Boolean summation operation to obtain a bionic lattice unit, and adjust the size of the bionic lattice unit to 3×3×3 mm 3 , the curved surface thickness is 175 μm, the beam rod diameter is 458 μm, and the porosity of the bionic lattice unit is 70%.

[0056] Furthermore, perform a periodic array on the bionic units so that the endpoints of the bionic units are connected to obtain a bionic lattice structure ( Figure 2 ). In this embodiment, the number of bionic unit arrays is 4×4×4, and the size of the bionic lattice structure is 12×12×12 mm 3 , and the porosity is 70%.

[0057] Convert the bionic lattice structure model into an STL format file.

[0058] Step 2: Prepare a bionic lattice structure part by laser powder bed melting

[0059] Import the STL file of the bionic lattice structure into slicing software for slicing processing to generate the printing path for each layer, and import the sliced file into a laser powder bed melting additive manufacturing system.

[0060] Preheat the NiTi alloy substrate to 200 °C, place NiTi alloy powder with a particle size of 15 - 53 μm in the powder chamber, and adjust the oxygen content in the forming chamber to 100 ppm.

[0061] Laser powder bed melting process parameters: laser power is 180 W, scanning speed is 2000 mm / s, spot diameter is 80 μm, scanning pitch is 60 μm, layer thickness is 30 μm, and the printing strategy is to rotate the laser path by 75° every other layer; obtain a bionic lattice structure part ( Figure 3 ).

[0062] Step 3: Compression performance test

[0063] Use a universal testing machine to conduct a quasi-static compression performance test on the obtained bionic lattice structure part, set the compression rate to 0.72 mm / min, and obtain the compression stress-strain curve of the bionic lattice structure, as shown in the appendix Figure 4 as shown.

[0064] Example 2

[0065] Step 1: Design of a lattice structure of a bionic sea urchin mouthpart - Aristotle's lantern

[0066] Extract key beam-shaped and curved surface-shaped design elements according to the external morphology and internal structure of the sea urchin mouthpart, design a truncated octahedron lattice unit based on a beam, with a unit size of 3×3×3 mm 3 , the beam rod diameter is 592 μm, and the unit porosity is 80%; design a Primitive triply periodic minimal surface lattice unit based on a curved surface, with a unit size of 3×3×3 mm 3 , the curved surface thickness is 175 μm, and the unit porosity is 80%.

[0067] Furthermore, use the Boolean sum operation to combine the truncated octahedron lattice unit and the Primitive triply periodic minimal surface lattice unit to obtain a bionic lattice unit, and adjust the size of the bionic lattice unit to 3×3×3 mm 3 , the curved surface thickness is 175 μm, the beam rod diameter is 592 μm, and the porosity of the bionic lattice unit is 70%.

[0068] Furthermore, perform a periodic array on the bionic unit so that the endpoints of the bionic unit are connected to obtain a bionic lattice structure ( Figure 5 ). In this example, the number of bionic unit arrays is 4×4×4, the size of the bionic lattice structure is 12×12×12 mm 3 , and the porosity is 70%.

[0069] Convert the bionic lattice structure model into an STL format file.

[0070] Step 2: Preparation of bionic lattice structure parts by laser powder bed melting

[0071] Import the STL file of the bionic lattice structure into slicing software for slicing to generate the printing path for each layer, and then import the sliced file into a laser powder bed melting additive manufacturing system.

[0072] Preheat the NiTi alloy substrate to 200 °C, place NiTi alloy powder with a particle size of 15 - 53 μm in the powder chamber, and adjust the oxygen content in the forming chamber to 100 ppm.

[0073] Laser powder bed melting process parameters: laser power is 180 W, scanning speed is 2000 mm / s, spot diameter is 80 μm, scanning spacing is 60 μm, thickness of each layer is 30 μm, and the printing strategy is to rotate the laser path by 75° every other layer; obtain the bionic lattice structure part( Figure 6 ).

[0074] Step 3: Compression performance test

[0075] Use a universal testing machine to conduct quasi-static compression performance testing on the prepared bionic lattice structure part, set the compression rate to 0.72 mm / min, and obtain the compression stress-strain curve of the bionic lattice structure, as shown in the appendix Figure 7 as follows.

[0076] Example 3

[0077] Step 1: Design of a bionic sea urchin mouthpart - Aristotle's lantern lattice structure

[0078] Extract key beam-like and curved surface-like design elements according to the external morphology and internal structure of the sea urchin mouthpart, design an octahedron + face-centered cubic lattice unit based on beams, with a unit size of 3×3×3 mm 3 , the beam rod diameter is 292 μm, and the unit porosity is 90%; design a Primitive triply periodic minimal surface lattice unit based on curved surfaces, with a unit size of 3×3×3 mm 3 , the curved surface thickness is 175 μm, and the unit porosity is 80%.

[0079] Furthermore, use Boolean summation operation to combine the octahedron + face-centered cubic lattice unit and the Primitive triply periodic minimal surface lattice unit to obtain a bionic lattice unit, and adjust the size of the bionic lattice unit to 3×3×3 mm 3 , the curved surface thickness is 175 μm, the beam rod diameter is 290 μm, and the porosity of the bionic lattice unit is 70%.

[0080] Furthermore, perform periodic array on the bionic units so that the endpoints of the bionic units are connected to obtain a bionic lattice structure( Figure 8)。In this embodiment, the number of bionic unit arrays is 4×4×4, the size of the bionic lattice structure is 12×12×12 mm 3 , and the porosity is 70%.

[0081] Convert the bionic lattice structure model into an STL format file.

[0082] Step 2: Fabricate the bionic lattice structure part by laser powder bed melting

[0083] Import the STL file of the bionic lattice structure into slicing software for slicing to generate the printing path for each layer, and then import the sliced file into the laser powder bed melting additive manufacturing system.

[0084] Preheat the NiTi alloy substrate to 200 °C, place NiTi alloy powder with a particle size of 15 - 53 μm in the powder chamber, and adjust the oxygen content in the forming chamber to 100 ppm.

[0085] Laser powder bed melting process parameters: laser power is 180 W, scanning speed is 2000 mm / s, spot diameter is 80 μm, scanning spacing is 60 μm, thickness of each layer is 30 μm, and the printing strategy is to rotate the laser path by 75° every other layer; obtain the bionic lattice structure part ( Figure 9 ).

[0086] Step 3: Compression performance test

[0087] Use a universal testing machine to conduct quasi-static compression performance testing on the fabricated bionic lattice structure part, set the compression rate to 0.72 mm / min, and obtain the compression stress-strain curve of the bionic lattice structure, as shown in the appendix Figure 10 .

[0088] Example 4

[0089] Step 1: Design of a lattice structure of a bionic sea urchin mouthpart - Aristotle's lantern

[0090] Extract the key beam-like and curved surface-like design elements according to the external morphology and internal structure of the sea urchin mouthpart, design a face-centered cubic lattice unit based on beams, with a unit size of 2×2×2 mm 3 , the beam rod diameter is 180 μm, and the unit porosity is 95%; design a Gyroid triply periodic minimal surface lattice unit based on curved surfaces, with a unit size of 2×2×2 mm 3 , the thickness of the curved surface is 180 μm, and the unit porosity is 82%.

[0091] Furthermore, use the Boolean sum operation to combine the face-centered cubic lattice unit and the Gyroid triply periodic minimal surface unit to obtain a bionic lattice unit, and adjust the size of the bionic lattice unit to 2×2×2 mm 3, the surface thickness is 180 μm, the beam rod diameter is 180 μm, and the porosity of the bionic lattice unit is 80%.

[0092] Further, the bionic units are periodically arrayed so that the endpoints of the bionic units are connected to obtain a bionic lattice structure ( Figure 11 ). In this embodiment, the number of bionic unit arrays is 8×8×8, and the size of the bionic lattice structure is 16×16×16 mm 3 , and the porosity is 80%.

[0093] Convert the bionic lattice structure model into an STL format file.

[0094] Step 2: Preparation of bionic lattice structure parts by laser powder bed melting

[0095] Import the STL file of the bionic lattice structure into slicing software for slicing processing to generate the printing path for each layer, and import the sliced file into a laser powder bed melting additive manufacturing system.

[0096] Preheat the NiTi alloy substrate to 200 °C, place NiTi alloy powder with a particle size of 15 - 53 μm in the powder chamber, and adjust the oxygen content in the forming chamber to 100 ppm.

[0097] Laser powder bed melting process parameters: laser power is 180 W, scanning speed is 2000 mm / s, spot diameter is 80 μm, scanning spacing is 60 μm, thickness of each layer is 30 μm, and the printing strategy is to rotate the laser path by 75° every other layer; obtain bionic lattice structure parts.

[0098] Step 3: Compression performance test

[0099] Use a universal testing machine to conduct a quasi-static compression performance test on the prepared bionic lattice structure parts, and set the compression rate to 0.72 mm / min.

[0100] Example 5

[0101] Step 1: Design of a lattice structure of a bionic sea urchin mouthpart - Aristotle's lantern

[0102] Extract the key beam-like and panel-like design elements according to the external morphology and internal structure of the sea urchin mouthpart, and design a dodecahedral lattice unit based on beams with a unit size of 4×4×4 mm 3 , the beam rod diameter is 700 μm, and the unit porosity is 75%; design a rotating square honeycomb lattice unit based on panels with a unit size of 4×4×4 mm 3 , the panel thickness is 650 μm, and the unit porosity is 59.31%.

[0103] Further, the dodecahedron lattice unit and the rotated square honeycomb lattice unit are combined by Boolean summation operation to obtain a bionic lattice unit, and the size of the bionic lattice unit is adjusted to 4×4×4 mm 3 , the panel thickness is 650 μm, the beam and rod diameter is 700 μm, and the porosity of the bionic lattice unit is 50%.

[0104] Further, the bionic units are periodically arrayed so that the endpoints of the bionic units are connected to obtain a bionic lattice structure ( Figure 12 ). In this embodiment, the number of bionic unit arrays is 10×3×2, and the size of the bionic lattice structure is 40×12×8 mm 3 , and the porosity is 50%.

[0105] Convert the bionic lattice structure model into an STL format file.

[0106] Step 2: Fabricate the bionic lattice structure part by laser powder bed melting

[0107] Import the STL file of the bionic lattice structure into slicing software for slicing processing to generate the printing path for each layer, and import the sliced file into a laser powder bed melting additive manufacturing system.

[0108] Preheat the NiTi alloy substrate to 200 °C, place the NiTi alloy powder with a particle size of 15 - 53 μm in the powder chamber, and adjust the oxygen content in the forming chamber to 100 ppm.

[0109] Laser powder bed melting process parameters: laser power is 180 W, scanning speed is 2000 mm / s, spot diameter is 80 μm, scanning spacing is 60 μm, thickness of each layer is 30 μm, and the printing strategy is to rotate the laser path by 75° every other layer; obtain the bionic lattice structure part.

[0110] Step 3: Flexural performance test

[0111] Use a universal testing machine to conduct a three-point bending test on the fabricated bionic lattice structure part, and set the loading rate to 0.5 mm / min to achieve quasi-static loading.

[0112] Example 6

[0113] Step 1: Design of a lattice structure of a bionic sea urchin mouthpart - Aristotle's lantern

[0114] Extract the key beam-like and curved surface-like design elements according to the external morphology and internal structure of the sea urchin mouthpart, and design an octahedron lattice unit based on beams, with a unit size of 4×4×4 mm 3 , the beam and rod diameter is 700 μm, and the unit porosity is 70%; design a Diamond triply periodic minimal surface lattice unit based on curved surfaces, with a unit size of 4×4×4 mm 3, the surface thickness is 1200μm, and the unit porosity is 30%.

[0115] Further, the octahedron lattice unit and the Diamond three-period minimal surface lattice unit are combined by Boolean summation operation to obtain a bionic lattice unit, and the size of the bionic lattice unit is adjusted to 4×4×4mm 3 , the surface thickness is 1200μm, the beam and rod diameter is 700μm, and the porosity of the bionic lattice unit is 23%.

[0116] Further, the bionic units are periodically arrayed so that the endpoints of the bionic units are connected to obtain a bionic lattice structure ( Figure 12 ). In this embodiment, the number of bionic unit arrays is 10×3×2, and the size of the bionic lattice structure is 40×12×8mm 3 , and the porosity is 23%.

[0117] Convert the bionic lattice structure model into an STL format file.

[0118] Step 2: Fabricate the bionic lattice structure part by laser powder bed melting

[0119] Import the STL file of the bionic lattice structure into slicing software for slicing processing to generate the printing path of each layer, and import the sliced file into the laser powder bed melting additive manufacturing system.

[0120] Preheat the NiTi alloy substrate to 200°C, place the NiTi alloy powder with a particle size of 15 - 53μm in the powder chamber, and adjust the oxygen content in the forming chamber to 100ppm.

[0121] Laser powder bed melting process parameters: laser power is 180W, scanning speed is 2000mm / s, spot diameter is 80μm, scanning spacing is 60μm, thickness of each layer is 30μm, and the printing strategy is to rotate the laser path by 75° every other layer; obtain the bionic lattice structure part.

[0122] Step 3: Flexural performance test

[0123] Use a universal testing machine to conduct a three-point bending test on the fabricated bionic lattice structure, and set the loading rate to 0.5mm / min to achieve quasi-static loading.

[0124] Comparative Example 1

[0125] Step 1: Design a Primitive three-period minimal surface lattice unit based on a surface, with a unit size of 3×3×3mm 3 , the surface thickness is 262μm, and the unit porosity is 70%.

[0126] Further, the unit cells of the Primitive triply periodic minimal surface are periodically arrayed, and the endpoints of the cells are connected to obtain the Primitive triply periodic minimal surface lattice structure ( Figure 13 ). In this comparative example, the number of unit arrays is 4×4×4, the lattice structure size is 12×12×12 mm 3 , and the porosity is 70%.

[0127] Convert the lattice structure model into an STL format file.

[0128] Step 2: Fabricate the lattice structure part by laser powder bed melting

[0129] Import the STL file of the lattice structure into slicing software for slicing to generate the printing path for each layer, and then import the sliced file into a laser powder bed melting additive manufacturing system.

[0130] Preheat the NiTi alloy substrate to 200 °C, place NiTi alloy powder with a particle size of 15 - 53 μm in the powder chamber, and adjust the oxygen content in the forming chamber to 100 ppm.

[0131] Laser powder bed melting process parameters: laser power is 180 W, scanning speed is 2000 mm / s, spot diameter is 80 μm, scanning spacing is 60 μm, layer thickness is 30 μm, and the printing strategy is to rotate the laser path by 75° every other layer; obtain the bionic lattice structure part ( Figure 14 ).

[0132] Step 3: Compression performance test

[0133] Use a universal testing machine to conduct a quasi-static compression performance test on the fabricated lattice structure part, set the compression rate to 0.72 mm / min, and obtain the compression stress-strain curve of the lattice structure, as shown in the appendix Figure 15 .

[0134] In Comparative Example 1, the lattice structure fails instantly after reaching the compressive strength, losing the ability to continue bearing loads and absorb energy. While in Examples 1 - 3, the lattice structures of the bionic sea urchin mouthpart - Aristotle's lantern not only have better fracture strength and fracture strain, but also due to the interaction between beam elements and surface elements during the loading process, the structure can still continue to bear loads and has the ability to absorb energy after reaching the compressive strength.

[0135] By comparing Examples 1 - 3 and Comparative Example 1, it can be seen that under the condition of ensuring the same porosity, the bionic lattice structure inspired by the sea urchin mouthpart - Aristotle's lantern in the present invention has better compressive mechanical properties and energy absorption characteristics (calculated from the force - displacement or stress - strain curve).

[0136] In summary, the lattice structure of a bionic sea urchin mouthpart - Aristotle's lantern proposed by the present invention can be formed by additive manufacturing technology, has good designability and manufacturability, has the characteristics of lightweight compression resistance and lightweight energy absorption, and has great engineering application potential in the field of lightweight lattice structures.

[0137] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications made without departing from the spirit and principle of the present invention shall be equivalent replacement methods and are all included in the protection scope of the present invention.

Claims

1. A design method for the lattice structure of a bionic sea urchin mouthpart - Aristotle's lantern, characterized in that, Including the following steps: Step 1: Extract the design elements of beams and surfaces according to the external morphology and internal structural characteristics of the sea urchin mouthpart - Aristotle's lantern. Design lattice units based on panels, surfaces and beams through 3D modeling software, and establish the relevant parameter ranges for each lattice unit; Step 2: Combine the lattice units based on panels, surfaces and beams by Boolean summation operation; optimize and adjust the local characteristics of the combined units based on structure and function to obtain bionic lattice units; Step 3: Perform periodic array on the bionic lattice units so that the endpoints of the bionic lattice units are connected to obtain a bionic lattice structure.

2. The design method according to claim 1, characterized in that, The lattice unit based on panel in Step 1 is one of triangular honeycomb, hexagonal honeycomb, concave corner honeycomb, square honeycomb, face-centered cubic foam, body-centered cubic foam and simple cubic foam; And / or, the size of the lattice unit based on panel in Step 1 is 1 - 20 mm, the panel thickness is 5 - 70% of the unit size, and the porosity of the lattice unit is 10 - 95%; And / or, the lattice unit based on surface in Step 1 is one of Primitive, Diamond, Gyroid, Neovius and Lidinoid of triply periodic minimal surface; And / or, the size of the lattice unit based on surface in Step 1 is 1 - 20 mm, the surface thickness is 5 - 70% of the unit size, and the porosity of the lattice unit is 10 - 95%; And / or, the lattice unit based on beam in Step 1 is one of octahedron, cube, body-centered cubic, face-centered cubic, dodecahedron, diamond, truncated octahedron, octahedron + cube, body-centered cubic + face-centered cubic, octahedron + face-centered cubic; And / or, the size of the lattice unit based on beam in Step 1 is 1 - 20 mm, the diameter of the beam is 5 - 70% of the unit size, and the porosity of the lattice unit is 10 - 95%.

3. The design method according to claim 2, wherein The lattice unit based on panel in Step 1 is a rotating square honeycomb; And / or, the size of the lattice unit based on panel in Step 1 is 4 mm, the panel thickness is 16% of the unit size, and the porosity of the lattice unit is 59%; And / or, the lattice unit based on surface in Step 1 is one of Primitive, Diamond and Gyroid of triply periodic minimal surface; And / or, the size of the lattice unit based on surface in Step 1 is 2 - 4 mm, the surface thickness is 6 - 30% of the unit size, and the porosity of the lattice unit is 30 - 82%; And / or, the lattice unit based on beam in Step 1 is one of body-centered cubic, truncated octahedron, octahedron + face-centered cubic, face-centered cubic, dodecahedron; And / or, the size of the lattice unit based on beam in Step 1 is 2 - 4 mm, the diameter of the beam is 9 - 20% of the unit size, and the porosity of the lattice unit is 70 - 95%.

4. The design method according to claim 1 or 2, characterized in that, The local characteristics in Step 2 are at least one of beam diameter, panel thickness, surface thickness, unit size and porosity; And / or, the beam diameter, panel thickness, surface thickness, unit size are consistent with those of the lattice unit in Step 1; And / or, the porosity of the bionic lattice unit described in Step 2 is 10-95% or 23-80%; And / or, the porosity of the bionic lattice structure described in Step 3 is 10-95% or 23-80%.

5. The design method according to claim 1 or 2, characterized in that, The number of the periodic arrays described in Step 3 is 2×2×2 to 20×20×20; And / or, the 3D modeling software described in Step 1 is at least one of Solid Works, UG, Rhino grasshopper, Materialise Magics, nTopology, 3ds Max, Autodesk Maya, and MATLAB.

6. A lattice structure of a bionic sea urchin mouthpart - Aristotle's lantern obtained by the design method according to any one of claims 1 to 5.

7. Application of the dot matrix structure of the bionic sea urchin mouthpart - Aristotle's lantern according to claim 6, characterized in that, Application in the preparation of lightweight energy-absorbing, lightweight compressive, lightweight bending, and lightweight heat-dissipating structural components; And / or, the fields involved are at least one of biomedical devices, automobiles, ships, communications, energy, aerospace, construction engineering, and intelligent robots.

8. A method for preparing a structural member having the dot matrix structure of the bionic sea urchin mouthpart - Aristotle's lantern according to claim 6, characterized in that, Comprising the following steps: Preparing a structural component with a bionic lattice structure from the lattice structure of the bionic sea urchin mouthpart - Aristotle's lantern described in claim 6 by additive manufacturing technology; And / or, the additive manufacturing technology is at least one of laser powder bed melting, electron beam powder bed melting, laser directed energy deposition, arc additive manufacturing, binder jetting, material extrusion, and stereolithography; And / or, the raw materials used in the additive manufacturing technology include at least one of metals, polymers, ceramics, or their composites.

9. A structural component having the lattice structure of the bionic sea urchin mouthpart - Aristotle's lantern described in claim 6 obtained by the method described in claim 8.

10. Application of the structural component described in claim 9 in the fields of biomedical devices, automobiles, ships, communications, energy, aerospace, construction engineering, and intelligent robots.

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