Pillar lattice structure, design method, 3D printing device and printing method

Abstract

The invention provides a strut lattice structure. The strut lattice structure comprises an outer frame and an inner strut, the outer frame is of a cubic structure; the inner supporting columns are of X-shaped structures, and six inner supporting columns are arranged in each lattice and are respectively arranged on six square surfaces of the cube; the four ends of the X-shaped structure of the inner supporting column are connected with the four corners of the square face. On the second aspect, the invention further discloses a 3D printing device for manufacturing the strut lattice structure, and the 3D printing device comprises a printing platform, a selective laser melting device, a powder layer absorbing device and a fused deposition device. The selective laser melting device is used for providing laser cladding printing and printing the outer wall of the pillar of the pillar lattice; the powder layer absorbing device is used for absorbing metal powder in the outer wall of the supporting column at a fixed point; the fused deposition device is used for filling the area in the outer wall of the supporting column with a fused material.

Description

Technical Field

[0001] The present invention relates to the technical field of processing lattice pillar lattice superstructures in additive manufacturing, and in particular to a pillar lattice structure, a design method, a 3D printing device and a printing method. Background Art

[0002] Selective laser melting is a type of metal 3D printing technology. Selective laser melting forming technology is an advanced laser additive manufacturing technology developed based on the basic principle of prototype manufacturing technology. The three-dimensional digital model of the part is sliced ​​and layered through special software to obtain the contour data of each section. Then, a high-energy laser beam is used to selectively melt the metal powder layer by layer according to the contour data. The three-dimensional solid parts are manufactured by spreading the powder layer by layer, melting, solidifying and accumulating layer by layer.

[0003] Laser selective melting technology has significant advantages in the lightweight manufacturing of metal parts. One of its main manufacturing methods is to use a lattice structure instead of a solid structure. The lattice structure has high specific strength and specific stiffness, and has great mechanical performance advantages in low-density structures. Compared with traditional solid materials, the density of metal lattice materials is greatly reduced, and a lattice structure with the same performance can reduce weight by more than 70%. Summary of the invention

[0004] The object of the present invention is to provide a pillar lattice structure, a 3D printing device and a printing method to solve at least one technical problem existing in the prior art.

[0005] In order to solve the above technical problems, the present invention provides a pillar lattice structure, comprising an outer frame and inner pillars; The outer frame is a cubic structure; The inner pillars are of X-shaped structure, with 6 arranged in each lattice, respectively arranged on the six square faces of the cube; The four ends of the inner support X-shaped structure are connected to the four corners of the square surface; The outer frame and the inner support are double-layer structures, including a support outer wall and an inner filling core; The outer wall of the pillar and the inner filling core are made of different materials respectively; The inner side of the outer wall of the pillar and the outer side of the inner filling core are melt-connected at the junction.

[0006] In a second aspect, the present application also discloses a 3D printing device for manufacturing a pillar lattice structure, comprising: a printing platform, a selective laser melting device, a powder layer absorption device and a molten deposition device; The selective laser melting device is used to provide laser cladding printing to print the outer wall of the pillars of the pillar lattice; The powder layer absorption device is used to absorb the metal powder inside the outer wall of the pillar at a fixed point; The molten deposition device is used to fill the area inside the outer wall of the pillar with molten material.

[0007] Further, the molten deposition device comprises a printing nozzle, a wire feed guide wheel, a printing wire made of a second material and a heating part; The printing wire is driven by the wire feed guide wheel to enter the printing nozzle; The printing nozzle is provided with a heating part for heating and melting the printing filament entering the printing nozzle.

[0008] Furthermore, the molten deposition device also includes a temperature sensor, a temperature measuring device and a controller; The controller is used to control the movement and printing of the print head according to a preset program; The temperature sensor is arranged on the printing nozzle and is used to detect the temperature of the molten material at the printing nozzle; The temperature measuring device is an infrared thermometer, which is arranged on the printing platform and is used to detect the temperature of the pillar lattice structure on the printing platform; The temperature sensor and the temperature measuring device are both electrically connected to the controller.

[0009] Further, the selective laser melting device includes a powder storage bin, a lifting part, a powder scraper, a lifting platform, a laser and a scanner; The powder storage bin is provided with metal powder made of a first material, and the lifting part is provided at the bottom end of the powder storage bin; The top of the lifting platform and the top of the powder storage bin are located on the same horizontal plane; The lifting part is lifted to push out the metal powder in the powder storage bin, and the powder scraper is horizontally movably arranged above the powder storage bin and the lifting platform. The protruding metal powder is evenly spread on the lifting platform, i.e., the forming platform, to form a powder bed under the push of the powder scraper. The laser is used to emit laser light and transmit the laser light to the scanner; The scanner receives the laser light generated by the laser and changes the path of the laser light through a galvanometer, thereby controlling the emission of the laser light.

[0010] Furthermore, the powder layer absorption device includes an air jet head, an air suction device and an air jet device; The diameter of the jet head is smaller than the inner diameter of the outer wall of the pillar; The jet head comprises an outer package area and an inner package tube, wherein the outer package area is arranged outside the inner package tube; The inner tube is a tube body connected to the air suction device; The outer package area is connected to the jet device through a pipeline; At least one circle of gas injection holes is circumferentially arranged on the side wall of the outer package area.

[0011] Furthermore, it also includes a three-degree-of-freedom feeding device; The three-degree-of-freedom feeding device is arranged on the printing platform; The powder layer absorbing device and the molten deposition device are arranged on the three-degree-of-freedom feeding device.

[0012] Further, the three-degree-of-freedom feeding device includes a first drive motor, a second drive motor, a telescopic cylinder, a first guide rail and a second guide rail; The powder layer absorption device and the molten deposition device are mounted on the telescopic rod of the telescopic cylinder; The telescopic cylinder is vertically inverted and is used to drive the powder layer absorbing device and the molten deposition device to move along the z-axis; The second driving motor is movably mounted on the second guide rail, the top of the telescopic cylinder is mounted on the second driving motor, and the second driving motor is used to drive the telescopic cylinder to move along the x-axis on the second guide rail; The first driving motor is movably mounted on the first guide rail, the second guide rail is mounted on the first driving motor, and the first driving motor is used to drive the second guide rail to move along the y-axis on the first guide rail.

[0013] In a third aspect, the present application also discloses a design method for a pillar lattice structure, comprising the steps of: B1: Construct an XYZ three-dimensional coordinate system in three-dimensional space and determine the specific size and number of reciprocal lattice vectors required for reciprocal space construction; B2: Use the Fourier transform principle to map the reciprocal lattice vector from the reciprocal space to the real space. Derive the mathematical expression of the target superlattice polarization pattern and draw the corresponding curve graph accordingly; B3: In the Y-axis direction, design the specific graphics of the target superlattice polarization pattern and obtain its nonlinear coefficient by calculation; B4: The pattern is combined into a basic unit pattern within a complete polarization cycle by flipping and splicing. B5: By replicating and arranging these basic unit patterns, the entire target superlattice polarization pattern is constructed.

[0014] In a fourth aspect, the present application further discloses a printing method of a 3D printing device, comprising the steps of: S1: Add printing materials; S2: Set printing parameters; S3: Printing environment preprocessing; S4: Selective laser melting device prints the outer wall of the pillars of the pillar lattice; S5: The powder layer absorption device absorbs the metal powder inside the outer wall of the pillar at a fixed point; S6: heating the outer wall of the pillar; S7: The molten deposition device fills the area inside the outer wall of the pillar with molten material; S8: Repeat steps S4-S7 until printing is completed.

[0015] By adopting the above technical solution, the present invention has the following beneficial effects: (1) The X-shaped inner pillar structure is adopted, and 6 such pillars are set on the six faces of each cube, which greatly enhances the stability and bearing capacity of the overall structure. This layout can effectively disperse and resist external forces from different directions, improving the durability and safety of the structure.

[0016] (2) The double-layer structure of the outer frame and inner pillars can further improve the rigidity and toughness of the structure. The outer wall of the pillar and the inner core are made of different materials. The best material combination can be selected according to actual needs to optimize the overall performance of the structure.

[0017] (3) The diversity of material choices for the pillar outer wall and inner core provides more possibilities for the structure. The most suitable material combination can be selected according to different application scenarios and load requirements. For example, the outer wall can be made of high-strength material to improve the compressive performance, while the inner core can be made of lightweight material to reduce the overall weight.

[0018] (4) Double-layer structure design During the manufacturing process, the outer wall of the pillar and the inner filling core are tightly combined through the fusion connection technology, which not only simplifies the manufacturing process and reduces the production cost, but also improves the overall quality of the structure. In addition, this connection method also ensures the durability of the structure.

[0019] (5) The design of the pillar lattice structure is flexible and can adapt to different application scenarios and size requirements. Whether it is used as a support system for building structures or as a skeleton structure for other industrial equipment, it can exert its excellent performance.

[0020] (6) By combining a selective laser melting device and a fused deposition device, the 3D printing device can flexibly manufacture complex parts with a pillar lattice structure. This flexibility allows the outer wall of the pillar and the internal filling material to be customized according to specific needs, thereby optimizing the performance of the part.

[0021] (7) Allowing the use of materials with different melting points (such as a first material and a second material) for printing makes it possible to manufacture pillar lattice structures with specific performance requirements. Low melting point materials can be used to quickly build the outer wall of the pillar, while high melting point materials can be used to fill the inner area to provide additional strength or functionality.

[0022] (8) The printing accuracy and surface quality of the pillar lattice structure can be ensured by precise control of the selective laser melting device and the molten deposition device. At the same time, the three-degree-of-freedom feeding device can achieve high-precision positioning and control of the printing nozzle and the powder layer absorption device, thereby improving the printing efficiency.

[0023] (9) The design of the powder layer absorption device allows precise control of the metal powder absorption inside the outer wall of the pillar, thereby optimizing the structure and performance of the internal space. Through the cooperation of the jet device and the suction device, precise powder removal and molten material filling can be achieved.

[0024] (10) The intelligent components such as controller, temperature sensor and temperature measuring device in this technical solution make the printing process more automated and intelligent. The movement and printing of the print head can be controlled by preset programs, and the temperature can be monitored and adjusted in real time, which can ensure the stability and reliability of the printing process.

[0025] (11) The printed pillar lattice structure can be post-processed by electromagnetic induction heating through the induction coil set on the printing platform to further improve its performance and service life. This post-processing function makes it possible to manufacture high-quality and high-performance pillar lattice structures.

[0026] (12) The powder layer absorption device absorbs the metal powder inside the outer wall of the pillar at a fixed point, ensuring the accurate use of materials during the printing process and reducing the influencing factors during the printing process.

[0027] (13) By heating the outer wall of the pillar, the two materials can be better connected after the molten material is filled in the molten deposition device, thereby improving the overall strength of the pillar lattice structure. This increase in structural strength is crucial for application scenarios that need to withstand heavy loads or high stresses.

[0028] (14) Through the environmental pretreatment step, the technical solution can ensure a stable printing environment and reduce deformation and errors during the printing process.

[0029] (15) This technical solution is applicable to a variety of printing materials and structures. Users can set different printing parameters according to specific needs to achieve customized printing. In addition, this technical solution can also be combined with other printing technologies to expand its application scope. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0031] Figure 1 is a schematic diagram of the three-dimensional structure of the pillar lattice structure; Figure 2 is a cross-sectional profile of the outer frame and inner struts of the lattice structure; Figure 3 is a cross-sectional view of the entire part of the lattice structure; Figure 4 A schematic diagram of the three-dimensional structure of a 3D printing device for manufacturing a pillar lattice structure; Figure 5 It is a schematic diagram of the three-dimensional structure of a fused deposition apparatus; Figure 6 It is a schematic diagram of the three-dimensional structure of a selective laser melting device; Figure 7 It is a schematic diagram of the three-dimensional structure of the powder layer absorption device; Figure 8 for Figure 7 A partial cross-sectional view of Fig. 9 for Figure 7 Schematic diagram of the plane structure of the jet pipe position; Fig.10 It is a flow chart of a printing method of a 3D printing device; Fig.11 for Fig.10 Detailed flow chart of step S1; Fig.12 for Fig.10 Detailed flow chart of step S2; Fig.13 for Fig.10 Detailed flow chart of step S3; Fig.14 for Fig.10 Detailed flow chart of step S4; Fig.15 for Fig.10 Detailed flow chart of step S5; Fig.16 for Fig.10 Step S6 is a detailed flow chart of the first set of solutions; Fig.17 for Fig.10 Detailed flow chart of step S7; Fig.18 for Fig.15Detailed flow chart of step S52; Fig.19 for Fig.15 Detailed flow chart of step S53; Fig. 20 for Fig.17 Detailed flow chart of step S71; Fig.21 for Fig.10 Step S6 is a detailed flow chart of the second solution; Fig. 22 The present invention is a flow chart of a method for recycling pillar lattice structure materials.

[0032] Reference numerals: 1-outer frame; 2-inner pillar; 3-outer wall of pillar; 4-inner filling core; 5-printing platform; 6-printing nozzle; 7-wire feed guide wheel; 8-printing wire material; 9-heating part; 10-temperature sensor; 11-powder storage bin; 12-lifting part; 13-powder scraper; 14-laser; 15-scanner; 16-jet head; 17-suction device; 18-jet device; 19-outer packaging area; 20-inner packaging tube; 21-jet hole; 22-first drive motor; 23-second drive motor; 24-telescopic cylinder; 25-first guide rail; 26-second guide rail; 27-scraper drive motor; 28-scraper guide rail; 29-lifting platform. DETAILED DESCRIPTION

[0033] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0035] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] The present invention is further explained below in conjunction with specific implementation modes.

[0037] Embodiment 1: like Figure 1 The figure shows a pillar lattice structure disclosed in this embodiment, including an outer frame 1 and inner pillars 2; The outer frame 1 is a cubic structure; The inner pillars 2 are of X-shaped structure, with 6 arranged in each lattice, respectively arranged on the six square faces of the cube; The four ends of the inner support 2X-shaped structure are connected to the four corners of the square surface.

[0038] like Figure 2-3 As shown, the outer frame 1 and the inner support 2 are double-layer structures, including a support outer wall 3 and an inner filling core 4; The pillar outer wall 3 and the inner filling core 4 are made of different materials respectively; The inner side of the pillar outer wall 3 and the outer side of the inner filling core 4 are melt-connected at the junction.

[0039] By adopting the above technical solution, the present invention has the following beneficial effects: (1) The use of an X-shaped inner support 2 structure, with 6 such supports set on each of the six faces of the cube, greatly enhances the stability and load-bearing capacity of the overall structure. This layout can effectively disperse and resist external forces from different directions, improving the durability and safety of the structure.

[0040] (2) The double-layer structure of the outer frame 1 and the inner support 2 can further improve the rigidity and toughness of the structure. The outer wall 3 of the support and the inner core 4 are made of different materials, and the best material combination can be selected according to actual needs to optimize the overall performance of the structure.

[0041] (3) The diversity of material choices for the pillar outer wall 3 and the inner filling core 4 provides more possibilities for the structure. The most suitable material combination can be selected according to different application scenarios and load requirements. For example, the outer wall can be made of high-strength material to improve the compressive performance, while the inner filling core 4 can be made of lightweight material to reduce the overall weight.

[0042] (4) Double-layer structure design During the manufacturing process, the outer wall 3 of the pillar and the inner filling core 4 are tightly combined through the fusion connection technology, which not only simplifies the manufacturing process and reduces the production cost, but also improves the overall quality of the structure. In addition, this connection method also ensures the durability of the structure.

[0043] (5) The design of the pillar lattice structure is flexible and can adapt to different application scenarios and size requirements. Whether it is used as a support system for building structures or as a skeleton structure for other industrial equipment, it can exert its excellent performance.

[0044] Embodiment 2: like Figure 4-9 As shown, this embodiment discloses a 3D printing device for manufacturing a pillar lattice structure, comprising: a printing platform 5, a selective laser melting device, a powder layer absorption device and a molten deposition device; The selective laser melting device is used to provide laser cladding printing to print the pillar outer wall 3 of the pillar lattice; The powder layer absorption device is used to absorb the metal powder in the outer wall 3 of the pillar at a fixed point; The molten deposition device is used to fill the area inside the outer wall 3 of the pillar with molten material.

[0045] As a further implementation of this embodiment, the molten deposition device includes a printing nozzle 6, a wire feed guide wheel 7, a printing wire 8 made of a second material and a heating part 9; The printing wire 8 is driven by the wire feed guide wheel 7 to enter the printing nozzle 6; The printing nozzle 6 is provided with a heating unit 9 for heating and melting the printing wire 8 entering the printing nozzle 6 .

[0046] like Figure 5 It is shown as a further implementation of this embodiment, the molten deposition device further includes a temperature sensor 10, a temperature measuring device and a controller; The controller is used to control the movement and printing of the print head 6 according to a preset program; The temperature sensor 10 is disposed on the print head 6 and is used to detect the temperature of the molten material at the print head 6; The temperature measuring device is an infrared thermometer, which is arranged on the printing platform 5 and is used to detect the temperature of the pillar lattice structure on the printing platform 5; The temperature sensor 10 and the temperature measuring device are both electrically connected to the controller.

[0047] When the temperature measuring device detects that the pillar lattice structure on the printing platform 5 is cooled to a preset temperature range, the printing nozzle 6 starts to work.

[0048] like Figure 6 The figure shows a further implementation of this embodiment, wherein the selective laser melting device comprises a powder storage bin 11, a lifting part 12, a powder scraper 13, a lifting platform 29, a laser 14 and a scanner 15; The powder storage bin 11 is provided with metal powder made of a first material, and the lifting portion 12 is provided at the bottom end of the powder storage bin 11; The top of the lifting platform 29 and the top of the powder storage bin are located on the same horizontal plane; The lifting part 12 is lifted to push out the metal powder in the powder storage bin 11, and the powder scraper 13 is horizontally movably arranged above the powder storage bin 11 and the lifting platform 29. The protruding metal powder is evenly spread on the lifting platform 29, i.e., the molding platform, under the push of the powder scraper 13 to form a powder bed; The laser 14 is used to emit laser light and transmit the laser light to the scanner 15; The scanner 15 receives the laser light generated by the laser 14 and changes the path of the laser light through a galvanometer, thereby controlling the emission of the laser light.

[0049] like Figure 7-9 The figure shows a further implementation of this embodiment, wherein the powder layer absorption device comprises an air jet head 16, an air suction device 17 and an air jet device 18; The diameter of the jet head 16 is smaller than the inner diameter of the pillar outer wall 3; The nozzle 16 includes an outer package area 19 and an inner package tube 20, wherein the outer package area 19 is arranged outside the inner package tube 20; The inner package tube 20 is a tube body connected to the air suction device 17; The outer packaging area 19 is connected to the jet device 18 through a pipeline; At least one circle of gas injection holes 21 is circumferentially arranged on the side wall of the outer package area 19 .

[0050] like Figure 4 Shown is a further implementation of this embodiment, further comprising a three-degree-of-freedom feeding device; The three-degree-of-freedom feeding device is arranged on the printing platform 5; The powder layer absorbing device and the molten deposition device are arranged on the three-degree-of-freedom feeding device.

[0051] As a further implementation of this embodiment, the three-degree-of-freedom feeding device includes a first drive motor 22, a second drive motor 23, a telescopic cylinder 24, a first guide rail 25 and a second guide rail 26; The powder layer absorption device and the molten deposition device are mounted on the telescopic rod of the telescopic cylinder 24; The telescopic cylinder 24 is vertically inverted and is used to drive the powder layer absorbing device and the molten deposition device to move along the z-axis; The second driving motor 23 is movably mounted on the second guide rail 26, and the top of the telescopic cylinder 24 is mounted on the second driving motor 23, and the second driving motor 23 is used to drive the telescopic cylinder 24 to move along the x-axis on the second guide rail 26; The first driving motor 22 is movably mounted on the first guide rail 25 , and the second guide rail 26 is mounted on the first driving motor 22 . The first driving motor 22 is used to drive the second guide rail 26 to move along the y-axis on the first guide rail 25 .

[0052] like Figure 4 It is shown as a further implementation of this embodiment, wherein the selective laser melting device further includes a scraper drive motor 27 and a scraper guide rail 28; The two scraper guide rails 28 are arranged oppositely on both sides of the printing platform 5, and the powder scraper 13 is arranged between the scraper guide rails 28; The scraper driving motor 27 is disposed at one end of the scraper guide rail 28 and is used to drive the powder scraper 13 to move along the scraper guide rail 28 .

[0053] As a further embodiment of the present application, an induction coil (not shown in the figure) is also provided on the printing platform 5 for performing electromagnetic induction heating on the printed pillar lattice structure.

[0054] By adopting the above technical solution, the present invention has the following beneficial effects: (1) By combining a selective laser melting device and a fused deposition device, the 3D printing device can flexibly manufacture complex components with a pillar lattice structure. This flexibility allows the pillar outer wall 3 and the internal filling material to be customized according to specific needs, thereby optimizing the performance of the component.

[0055] (2) It allows printing using materials with different melting points (e.g., a first material and a second material), which makes it possible to manufacture pillar lattice structures with specific performance requirements. Low melting point materials can be used to quickly build the outer wall of the pillar, while high melting point materials can be used to fill the inner area to provide additional strength or functionality.

[0056] (3) The printing accuracy and surface quality of the pillar lattice structure can be ensured by precise control of the selective laser melting device and the molten deposition device. At the same time, the three-degree-of-freedom feeding device can realize high-precision positioning and control of the print head 6 and the powder layer absorption device, thereby improving the printing efficiency.

[0057] (4) The design of the powder layer absorption device allows for precise control of the metal powder absorption within the pillar outer wall 3, thereby optimizing the structure and performance of the internal space. Through the cooperation of the jet device 18 and the suction device 17, precise powder removal and molten material filling can be achieved.

[0058] (5) The controller, temperature sensor 10 and temperature measuring device in the technical solution make the printing process more automated and intelligent. The movement and printing of the print head 6 are controlled by a preset program, and the temperature is monitored and adjusted in real time, which ensures the stability and reliability of the printing process.

[0059] (6) The printed pillar lattice structure can be post-processed by electromagnetic induction heating through the induction coil provided on the printing platform 5, thereby further improving its performance and service life. This post-processing function makes it possible to manufacture high-quality and high-performance pillar lattice structures.

[0060] Embodiment 3: like Fig.10 This embodiment discloses a printing method of a 3D printing device, including the steps of: S1: Add printing materials; S2: Set printing parameters; S3: Printing environment preprocessing; S4: Selective laser melting device prints the outer wall of the pillars of the pillar lattice; S5: The powder layer absorption device absorbs the metal powder inside the outer wall of the pillar at a fixed point; S6: heating the outer wall of the pillar; S7: The molten deposition device fills the area inside the outer wall of the pillar with molten material; S8: Repeat steps S4-S7 until printing is completed.

[0061] like Figure 2-3 As shown, through the printing method of the present application, a lattice pillar lattice composite metamaterial structure can be obtained, which has multiple application prospects in multiple performance improvement fields compared to traditional solid pillar lattice (SSL) and hollow pillar lattice (HSL) metamaterials. The performance of the composite structure is changed by changing the molten deposition to squeeze the molten material, for example, by adding polymer materials to the tube wall to increase the toughness of the structure, by adding copper to the tube wall to increase the conductivity of the structure, by adding steel to the tube wall to increase the stiffness of the structure, etc.

[0062] like Fig.11 It is shown as a further implementation of this embodiment, step S1 specifically comprises: S11: adding metal powder made of a first material into a powder storage bin, and placing a printing filament made of a second material into a filament feed guide wheel; S12: Flatten the metal powder in the powder storage bin and start the wire feed guide wheel to allow the printing filament to enter the printing nozzle.

[0063] like Fig.12 FIG. 2 is a further implementation of this embodiment, in which step S2 is specifically as follows: S21: Create a three-dimensional solid model of the part to be printed and export it in STL format; S22: Import the controller, slice the model in layers in the controller, and set printing parameters such as laser power, scanning speed, and scanning mode.

[0064] like Fig.13 It is shown as a further implementation of this embodiment, and step S3 is specifically: S31: placing the 3D printing device in a sealed space; S32: The air in the sealed space is extracted and filled with argon gas to reduce the oxygen content in the chamber to less than 200ppm to prevent metal oxidation during the printing process.

[0065] like Fig.14 It is shown as a further implementation of this embodiment, and step S4 is specifically: S41: The lifting part is lifted to push out the metal powder in the powder storage bin; S42: The powder scraper moves along the scraper guide rail to one side of the forming platform in the cabin under the drive of the scraper drive motor, and then returns to the initial position to evenly spread the metal powder on the printing platform to form a powder bed; S43: The selective laser melting device scans the metal powder bed with a laser according to the printing parameters set in step S2 to print the outer wall of the pillars of the pillar lattice.

[0066] like Fig.15 FIG. 5 is a further implementation of this embodiment, in which step S5 is specifically as follows: S51: Determine the position information of the hollow part of the outer wall of the pillar according to the parameters in step S2; S52: moving the jet head of the powder layer absorbing device to the hollow part of the outer wall of the pillar through the three-degree-of-freedom feeding device; S53: Turn on the powder layer absorption device to remove the metal powder; S54: Return the powder layer absorbing device to the initial position through the three-degree-of-freedom feeding device.

[0067] After the selective laser melting device is used for printing, metal powder will remain in the pillar outer wall 3 of the pillar lattice, and the residual metal powder will become impurities when the molten deposition device is working in step S7, affecting the quality of the finished product. Therefore, step S5 is required to absorb the residual metal powder.

[0068] like Fig.16 It is shown as a further implementation of this embodiment, and step S6 is specifically: S61a: Reduce the laser power of the selective laser melting unit to 90-95% of the original power; S62a: The selective laser melting device scans along the inner side of the outer wall of the pillar.

[0069] Scanning the inner side of the pillar outer wall 3 with 90-95% of the original power of the laser in step S61a and step S62a can rapidly heat the inner side of the pillar outer wall 3 to 75-90% of the melting point. When performing step S7, the molten second material can conduct heat to the inner side of the pillar outer wall 3 made of the first material, so that the pillar outer wall 3 is further heated, thereby melting its inner wall, and the inner side of the pillar outer wall 3 can penetrate each other with the molten second material after melting, and the interface between the two materials has more excellent mechanical properties after cooling.

[0070] like Fig.17 FIG. 1 is a further implementation of this embodiment, in which step S7 is specifically as follows: S71: moving the printing nozzle of the fused deposition device to above the hollow part of the outer wall of the pillar through the three-degree-of-freedom feeding device; S72: The printing filament is driven by the filament guide wheel to enter the printing nozzle, and the heating part is turned on to melt the printing filament; S73: The printing nozzle fills the molten printing filament into the hollow position of the outer wall of the pillar; S74: Returning the molten deposition device to the initial position through the three-degree-of-freedom feeding device.

[0071] like Fig.18 FIG. 5 is a further implementation of this embodiment, in which step S52 is specifically as follows: S521: driving the powder layer absorbing device to move along the y-axis on the first guide rail by means of a first driving motor; S522: driving the powder layer absorbing device to move along the x-axis on the second guide rail by a second driving motor; S523: The telescopic cylinder is used to drive the powder layer absorbing device to move along the z-axis.

[0072] like Fig.19 FIG. 5 is a further implementation of this embodiment, in which step S53 is specifically as follows: S531: Start the air suction device; S532: After the air suction device is turned on for 1 second, the air suction device is turned off and the air injection device is turned on; S533: 0.1s after the air injection device is turned on, the air suction device is turned on; S534: The air suction device is turned on for 0.5-1s and then turned off, and the air suction device and the air injection device are turned off at the same time.

[0073] After the suction device 17 is turned on in step S531, most of the metal powder in the hollow part of the pillar outer wall 3 can be sucked away, but a small amount of powder will still remain in the corner. Therefore, as shown in steps S532 and S533, the suction device 17 is turned off after suctioning for 1 second, and the jet device 18 is turned on. After the jet device 18 is turned on, the powder in the corner will be disturbed. Turning on the suction device 17 after an interval of 0.1 seconds can not only increase the disturbance to make it float, but also make the air in the hollow part of the pillar outer wall 3 circulate so as to inhale the powder floating in the air. If the time interval between the opening of the jet device 18 and the opening of the second suction device 17 is too large, the powder in the hollow of the pillar outer wall 3 will be scattered into the environment. Although it can also play the role of clearing the powder in the hollow of the pillar outer wall 3, there are three disadvantages: (1) The metal powder scattered into the environment is likely to affect the movement of the three-degree-of-freedom feeding device, reducing its accuracy and service life; (2) The powder sucked by the suction device 17 can be recycled, but it is difficult to recycle the powder after it is scattered into the environment; (3) After the seal is opened after printing, the metal powder may float out and affect the experimenter. Based on the above reasons and according to the inventor's multiple experiments, it is finally determined that the interval of 0.1 seconds is the optimal time interval, which can not only play the role of disturbance but also avoid the above three disadvantages.

[0074] like Fig. 20 FIG. 1 is a further implementation of this embodiment, in which step S71 is specifically as follows: S711: driving the molten deposition device to move along the y-axis on the first guide rail by a first driving motor; S712: driving the molten deposition device to move along the x-axis on the second guide rail by a second driving motor; S713: The telescopic cylinder is used to drive the molten deposition device to move along the z-axis.

[0075] By adopting the above technical solution, the present invention has the following beneficial effects: (1) The lattice pillar lattice composite metamaterial structure manufactured by this method has significant performance advantages over traditional solid or hollow pillar lattice metamaterials. By selectively filling molten materials with different properties, customized regulation of various properties such as structural toughness, conductivity, stiffness, etc. can be achieved to meet the needs of different application scenarios.

[0076] (2) Through precise printing parameter settings and printing environment pretreatment, as well as the application of laser melting technology, high-precision printing of the pillar outer wall 3 is achieved. At the same time, the residual metal powder in the pillar outer wall 3 is removed by the powder layer absorption device, ensuring the quality of the melt deposition process, thereby obtaining a high-quality composite metamaterial structure.

[0077] (3) The powder layer absorption device can effectively remove the metal powder remaining in the outer wall 3 of the pillar. The powder can be recycled and reused, thereby improving the utilization rate of materials and reducing production costs.

[0078] (4) The printing method realizes precise control of the print head 6 and the powder layer absorption device through the three-degree-of-freedom feeding device, making the printing process more flexible and automated. At the same time, through the preset printing parameters and program control, one-click printing can be achieved, thereby improving production efficiency.

[0079] (5) By controlling the working sequence of the jet device 18 and the suction device 17, the adverse effects of metal powders being dispersed into the environment on equipment and personnel are effectively avoided, and the recycling rate of the powders is also improved, meeting environmental protection requirements.

[0080] Embodiment 4: like Fig.21 The embodiment 4 of the present application is shown. This embodiment is basically the same as the embodiment 3, except that step S6 is specifically as follows: S61b: turning on the electromagnetic induction coil to heat the printed outer wall of the pillar, and turning on the temperature measuring device to measure the temperature of the outer wall of the pillar; S62b: When the temperature of the outer wall of the pillar reaches 75-90% of the melting point temperature, the electromagnetic induction coil and the temperature measuring device are turned off.

[0081] The temperature of the pillar outer wall 3 is brought to 75-90% of the melting point by electromagnetic induction in step S61b and step S62b. When performing step S7, the molten second material can conduct heat to the inner side of the pillar outer wall 3 made of the first material, so that the pillar outer wall 3 is further heated, thereby melting its inner wall, and the inner side of the pillar outer wall 3 can penetrate the molten second material after melting, and the interface between the two materials has better mechanical properties after cooling.

[0082] Compared with Example 3, the temperature of the pillar outer wall 3 can be controlled more accurately by the cooperation of the electromagnetic induction coil and the temperature measuring device. In addition, since Example 3 adopts local laser heating, the area of ​​the pillar outer wall 3 directly irradiated by the laser may melt directly while other areas are not heated enough, resulting in premature collapse of the pillar outer wall 3. In contrast, this embodiment uses electromagnetic induction heating to uniformly heat the pillar outer wall 3, thus avoiding the defects that may occur in Example 3.

[0083] By adopting the above technical solution, the present invention has the following beneficial effects: (1) The temperature of the printed pillar outer wall 3 can be more accurately controlled by using the electromagnetic induction coil and the temperature measuring device. This temperature control method enables the pillar outer wall 3 to reach the predetermined temperature range (75-90% of the melting point temperature) uniformly and accurately, providing ideal conditions for the subsequent molten deposition process.

[0084] (2) Compared with the method of using local laser heating, electromagnetic induction heating can ensure that the outer wall 3 of the pillar is heated more evenly. This can avoid the problem of local overheating and premature melting caused by direct laser irradiation, thereby reducing the risk of collapse of the outer wall 3 of the pillar and improving the stability of the printing process and the quality of the finished product.

[0085] (3) When the temperature of the pillar outer wall 3 reaches 75-90% of the melting point, the second material can transfer heat to the inner side of the pillar outer wall 3 made of the first material in a molten state. This heat transfer process causes the pillar outer wall 3 to further heat up until its inner wall reaches a molten state. Subsequently, the two materials penetrate each other in a molten state, and after cooling, the interface has more excellent mechanical properties. This close combination of materials not only improves the overall strength of the structure, but also enhances its anti-fatigue, anti-corrosion and other properties.

[0086] Embodiment 5: This embodiment provides a preferred solution for manufacturing the first material and the second material of the pillar lattice structure through Embodiment 3 or Embodiment 4.

[0087] The first material is fine steel, and the second material is titanium alloy.

[0088] When a collision occurs and the ambient temperature rises rapidly, since the thermal expansion coefficient of fine steel is slightly larger than that of titanium alloy, the first material will wrap the second material more tightly, so that the overall strength of the pillar lattice structure material is rapidly improved. The pillar lattice structure that needs to be recycled in this embodiment requires a molten connection at the junction of the first material and the second material. If it is a non-molten connection in the prior art, relative movement may occur between the first material and the second material. When a collision occurs and the temperature rises rapidly, in addition to expansion, the outer wall 3 of the pillar will also produce a torsional tendency due to the collision, and fracture will occur at the shear stress concentration point. However, when the pillar lattice structure is manufactured by Example 3 or Example 4, since the first material and the second material are molten at the junction, the torsional tendency will offset the bonding force provided by the molten connection, thereby avoiding shear stress concentration and fracture of the first material.

[0089] Due to this effect, the solution of this embodiment can be used in devices that need to deal with certain specific dangerous situations. When an explosion occurs (i.e., the material surfaces collide and the ambient temperature rises rapidly), the first material will wrap the second material more tightly, so that the overall strength of the pillar lattice structure material will increase rapidly, thereby improving the strength.

[0090] By adopting the above technical solution, the present invention has the following beneficial effects: (1) Through the fusion connection of fine steel and titanium alloy, the technical solution forms a strong bond between the first material and the second material of the pillar lattice structure. When a collision occurs and the ambient temperature rises rapidly, the fine steel will tightly wrap the titanium alloy due to its larger thermal expansion coefficient, thereby significantly improving the stability of the entire structure.

[0091] (2) When the ambient temperature rises sharply (such as in extreme situations such as explosions), the tight wrapping of the stainless steel around the titanium alloy rapidly increases the overall strength of the pillar lattice structure. This dynamic strengthening mechanism is particularly critical for applications that need to withstand high impact loads.

[0092] (3) The fusion connection method effectively avoids the relative movement between the first material and the second material, thereby eliminating the torsion tendency and shear stress concentration caused by collision. This design significantly reduces the risk of structural fracture under extreme conditions.

[0093] (4) This technical solution is not only suitable for the manufacture of pillar lattice structures, but can also be widely used in fields that require high structural stability and impact resistance, especially in the field of safety protection, showing great application potential.

[0094] Embodiment 6: This embodiment provides a preferred solution for manufacturing the first material and the second material of the pillar lattice structure through Embodiment 3 or Embodiment 4 and a method for recycling the pillar lattice structure material.

[0095] The first material is zinc, and the second material is aluminum alloy.

[0096] Zinc is a bluish-white metal with a relatively low melting point. At standard atmospheric pressure, the melting point of zinc is about 419.5°C. At the same time, the thermal expansion coefficient of zinc is also relatively large, at 30.2μm·m^-1·K^-1, which means that the volume of zinc changes significantly when the temperature changes.

[0097] Aluminum alloy is an alloy composed of aluminum and other metals (such as copper, magnesium, zinc, etc.), which has the characteristics of light weight and high strength. The melting point of aluminum alloy varies depending on the alloy composition, but is usually around 600°C. Compared with zinc, the thermal expansion coefficient of aluminum alloy is smaller. When the temperature changes by 1°C, the length of aluminum alloy will change by 0.01% to 0.0001% of its original length.

[0098] like Fig. 22 As shown, a method for recycling pillar lattice structure materials comprises the steps of: A1: Put the pillar lattice structure into liquid nitrogen. Due to the difference in thermal expansion coefficients between zinc and aluminum alloy, a large number of cracks appear in the zinc in the coolant; A2: Turn on the circulation pump to circulate the liquid nitrogen through the circulation pump to accelerate the heat exchange between the lattice structure and the liquid nitrogen, and speed up the stripping of zinc; A3: Turn off the circulation pump and take out the aluminum alloy material; A4: Filter the liquid nitrogen to obtain the zinc material.

[0099] The pillar lattice structure that needs to be recycled by this recycling method requires a fusion connection at the junction of the first material and the second material. If it is a non-fusion connection in the prior art, the first material and the second material may move relative to each other, and it is impossible to ensure that the first material cracks evenly, but only cracks at some stress concentration points. However, through the fusion connection method of the present application, the first material and the second material are tightly connected, but because the two materials have a large difference in thermal expansion coefficients, the first material will crack evenly on the surface of the second material to form a large number of cracked fragments, which can make the first material easier to peel off after the circulation pump drives the liquid nitrogen to circulate.

[0100] By adopting the above technical solution, the present invention has the following beneficial effects: (1) By utilizing the significant difference in thermal expansion coefficients between zinc and aluminum alloys, this technical solution can make the zinc material crack evenly in the pillar lattice structure under the cooling effect of liquid nitrogen, and then accelerate the flow of liquid nitrogen through a circulation pump to achieve efficient stripping of the zinc material. This recycling method not only simplifies the recycling process, but also improves the recycling efficiency.

[0101] (2) During the recycling process, zinc materials and aluminum alloy materials are effectively separated, ensuring a high recovery rate for both materials. Aluminum alloy materials, due to their light weight and high strength, can be reused in manufacturing new pillar lattice structures or other products after recycling, thus achieving the recycling of resources.

[0102] (3) This technical solution uses liquid nitrogen as the cooling medium. Liquid nitrogen does not produce harmful substances during the cooling process and is environmentally friendly. At the same time, liquid nitrogen can be recycled during the recovery process, reducing energy consumption and costs.

[0103] (4) This technical solution is applicable to the recycling of pillar lattice structure materials formed by fusion connection and has wide applicability. Other material combinations with different thermal expansion coefficients can also be recycled by similar methods.

[0104] Embodiment 7: This embodiment provides a design method of a pillar lattice structure, which comprises the following steps: B1: Construct an XYZ three-dimensional coordinate system in three-dimensional space and determine the specific size and number of reciprocal lattice vectors required for reciprocal space construction; B2: Use the Fourier transform principle to map the reciprocal lattice vector from the reciprocal space to the real space. Derive the mathematical expression of the target superlattice polarization pattern and draw the corresponding curve graph accordingly; B3: In the Y-axis direction, design the specific graphics of the target superlattice polarization pattern and obtain its nonlinear coefficient by calculation; B4: The pattern is combined into a basic unit pattern within a complete polarization cycle by flipping and splicing. B5: By replicating and arranging these basic unit patterns, the entire target superlattice polarization pattern is constructed.

[0105] By adopting the above technical solution, the present invention has the following beneficial effects: (1) By mapping the reciprocal lattice vector to real space through the Fourier transform method, the mathematical expression of the target superlattice polarization pattern can be accurately derived and an accurate curve graph can be drawn. This precise design method ensures the accuracy and reliability of the superlattice polarization pattern.

[0106] (2) The target superlattice polarization pattern is designed in the Y-axis direction, and the corresponding nonlinear coefficient is obtained by calculation, thereby enhancing the nonlinear performance of the superlattice material. This performance improvement has important application value in the fields of optoelectronic devices, sensors, etc.

[0107] (3) The basic unit pattern formed by flipping upside down and splicing can form a superlattice polarization pattern with a periodic structure after repeated arrangement. This periodic structure not only enhances the regularity of the pattern, but also helps to improve the stability and reliability of the superlattice material.

[0108] (4) Through precise calculation and design, this technology can predetermine the polarization pattern of the superlattice material before preparing it. This pre-design method can simplify the preparation process, reduce preparation costs, and improve production efficiency.

[0109] (5) The superlattice polarization pattern designed by this technology is highly customizable and flexible, and can be designed and adjusted according to different application requirements. Therefore, it has broad application prospects in optoelectronic devices, sensors, microelectronic devices and other fields.

[0110] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A pillar lattice structure, characterized in that: It includes an outer frame and inner pillars; The outer frame is a cubic structure; The inner pillars are of X-shaped structure, with 6 arranged in each lattice, respectively arranged on the six square faces of the cube; The four ends of the inner support X-shaped structure are connected to the four corners of the square surface; The outer frame and the inner support are double-layer structures, including a support outer wall and an inner filling core; The outer wall of the pillar and the inner filling core are made of different materials respectively; The inner side of the outer wall of the pillar and the outer side of the inner filling core are melt-connected at the junction.

2. A 3D printing device for manufacturing the pillar lattice structure according to claim 1, characterized in that: include: Printing platform, selective laser melting device, powder layer absorption device and fused deposition device; The selective laser melting device is used to provide laser cladding printing to print the outer wall of the pillars of the pillar lattice; The powder layer absorption device is used to absorb the metal powder inside the outer wall of the pillar at a fixed point; The molten deposition device is used to fill the area inside the outer wall of the pillar with molten material.

3. The 3D printing device according to claim 2, characterized in that: The molten deposition device comprises a printing nozzle, a wire feed guide wheel, a printing wire made of a second material and a heating part; The printing wire is driven by the wire feed guide wheel to enter the printing nozzle; The printing nozzle is provided with a heating part for heating and melting the printing filament entering the printing nozzle.

4. The 3D printing device according to claim 3, characterized in that: The molten deposition device also includes a temperature sensor, a temperature measuring device and a controller; The controller is used to control the movement and printing of the print head according to a preset program; The temperature sensor is arranged on the print head and is used to detect the temperature of the molten material at the print head; The temperature measuring device is an infrared thermometer, which is arranged on the printing platform and is used to detect the temperature of the pillar lattice structure on the printing platform; The temperature sensor and the temperature measuring device are both electrically connected to the controller.

5. The 3D printing device according to claim 3, characterized in that: The selective laser melting device includes a powder storage bin, a lifting part, a powder scraper, a lifting platform, a laser and a scanner; The powder storage bin is provided with metal powder made of a first material, and the lifting part is provided at the bottom end of the powder storage bin; The top of the lifting platform and the top of the powder storage bin are located on the same horizontal plane; The lifting part is lifted to push out the metal powder in the powder storage bin, and the powder scraper is horizontally movably arranged above the powder storage bin and the lifting platform. The protruding metal powder is evenly spread on the lifting platform to form a powder bed under the push of the powder scraper; The laser is used to emit laser light and transmit the laser light to the scanner; The scanner receives the laser light generated by the laser and changes the path of the laser light through a galvanometer, thereby controlling the emission of the laser light.

6. The 3D printing device according to claim 2, characterized in that: The powder layer absorption device comprises an air jet head, an air suction device and an air jet device; The diameter of the jet head is smaller than the inner diameter of the outer wall of the pillar; The jet head comprises an outer package area and an inner package tube, wherein the outer package area is arranged outside the inner package tube; The inner tube is a tube body connected to the air suction device; The outer package area is connected to the jet device through a pipeline; At least one circle of air-jet holes is circumferentially arranged on the side wall of the outer package area.

7. The 3D printing device according to claim 2, characterized in that: Also included is a three-degree-of-freedom feeding device; The three-degree-of-freedom feeding device is arranged on the printing platform; The powder layer absorbing device and the molten deposition device are arranged on the three-degree-of-freedom feeding device.

8. The 3D printing device according to claim 7, characterized in that: The three-degree-of-freedom feeding device includes a first drive motor, a second drive motor, a telescopic cylinder, a first guide rail and a second guide rail; The powder layer absorption device and the molten deposition device are mounted on the telescopic rod of the telescopic cylinder; The telescopic cylinder is vertically inverted and is used to drive the powder layer absorbing device and the molten deposition device to move along the z-axis; The second driving motor is movably mounted on the second guide rail, the top of the telescopic cylinder is mounted on the second driving motor, and the second driving motor is used to drive the telescopic cylinder to move along the x-axis on the second guide rail; The first driving motor is movably mounted on the first guide rail, the second guide rail is mounted on the first driving motor, and the first driving motor is used to drive the second guide rail to move along the y-axis on the first guide rail.

9. A design method for a pillar lattice structure, characterized in that: Includes steps: B1: Construct an XYZ three-dimensional coordinate system in three-dimensional space and determine the specific size and number of reciprocal lattice vectors required for reciprocal space construction; B2: Using the Fourier transform principle, the reciprocal lattice vector is mapped from the reciprocal space to the real space; the mathematical expression of the target superlattice polarization pattern is derived, and the corresponding curve graph is drawn accordingly; B3: In the Y-axis direction, design the specific graphics of the target superlattice polarization pattern and obtain its nonlinear coefficient by calculation; B4: The pattern is combined into a basic unit pattern within a complete polarization cycle by flipping and splicing. B5: By replicating and arranging these basic unit patterns, the entire target superlattice polarization pattern is constructed.

10. A printing method for the 3D printing device according to any one of claims 2 to 8, characterized in that: Includes steps: S1: Add printing materials; S2: Set printing parameters; S3: Printing environment preprocessing; S4: Selective laser melting device prints the outer wall of the pillars of the pillar lattice; S5: The powder layer absorption device absorbs the metal powder inside the outer wall of the pillar at a fixed point; S6: heating the outer wall of the pillar; S7: The molten deposition device fills the area inside the outer wall of the pillar with molten material; S8: Repeat steps S4-S7 until printing is completed.

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