Reinforced particle switchable composite material 3D printing device and method

Abstract

The invention relates to a 3D printing device and method for a reinforced particle switchable composite material. The device comprises a material conveying system, a reinforced particle switching system, a three-dimensional forming platform and a control system. The material conveying system is responsible for supplying raw materials to the reinforced particle switching system, and the reinforced particle switching system controls micro-nano-scale reinforced particles in suspension liquid through sound wave radiation force, so that accurate aggregation and separation of the reinforced particles are achieved. The three-dimensional forming platform controls movement of the multi-material extrusion system in a three-dimensional space to construct a three-dimensional object. The control system ensures that the reinforced particles in the printing material can be gathered, separated and switched in real time and is coordinated with the three-dimensional forming platform, and complex printing design is achieved. The method comprises the steps of material preparation, an additive manufacturing process and post-treatment, and gradient change and function integration of the material are achieved by dynamically switching different reinforced particle combinations.

Description

Technical Field

[0001] The present invention relates to the technical field of additive manufacturing, and in particular to a device and method for 3D printing of reinforced particle switchable composite materials. Background Art

[0002] In traditional 3D printing technology, the manufacture of composite materials usually involves uniformly dispersing reinforcing particles such as carbon fiber or glass fiber in the matrix material to improve the mechanical properties of the printed object. However, these methods have some limitations, such as: existing 3D printing technology is usually unable to dynamically adjust the type and distribution of reinforcing particles during the printing process, which means that it is impossible to optimize material properties according to the needs of different parts of the printed object.

[0003] In order to solve the above problems, the present invention proposes a 3D printing device and method for reinforced particle switchable composite materials, which realizes real-time dynamic aggregation and separation of reinforced particles by using acoustic radiation force to manipulate micro-nanoscale reinforced particles in suspension without contact. By precisely controlling the distribution and movement of reinforced particles and coordinating with the three-dimensional molding platform, the present invention can realize complex printing designs and provide a new method for manufacturing high-performance composite materials. Summary of the invention

[0004] The present invention provides a device and method for 3D printing of reinforced particle switchable composite materials, which aims to achieve the construction of complex three-dimensional objects by accurately controlling the distribution of reinforced particles and dynamically adjusting the local properties of the material. The device and method are particularly suitable for application scenarios that require material gradient changes and functional integration during the printing process.

[0005] A 3D printing device for reinforced particle switchable composite materials, comprising: Material delivery system, whose main function is to accurately, efficiently and reliably supply raw materials to the enhanced particle switching system; The enhanced particle switching system, as the core component of the 3D printing device, uses the acoustic radiation force to manipulate the micro-nanoscale enhanced particles in the suspension. This contactless method can achieve precise aggregation and separation of enhanced particles, thereby dynamically adjusting the local properties of the material during the printing process; The 3D molding platform is used to control the movement of the multi-material extrusion system in three-dimensional space, ensuring that multiple material systems containing different reinforcement particles can be accurately stacked layer by layer along a predetermined path to build a three-dimensional object. This precise control is essential for building complex three-dimensional objects, allowing for gradient changes in materials and functional integration during the printing process; Control system: ensures that the reinforcing particles in the printing material can be aggregated, separated, and switched in real time, and stacked layer by layer along the predetermined path with the matrix material. The control system is required to accurately control the distribution and movement of the reinforcing particles, as well as coordinate with the 3D molding platform to achieve complex printing designs; Furthermore, the material conveying system comprises: Material supply cylinder: used to store printing raw materials, the outlet is equipped with a control mechanism to ensure that the material can be delivered to the enhanced particle switching system at a predetermined rate of 6-83mm / s and in a predetermined manner; Material supply delivery channel: designed to take the raw materials out of the supply cylinder and deliver them to the inlet of the microfluidic chip in the enhanced particle switching system; Further, the enhanced particle switching system comprises: Microfluidic chip: It contains micro-scale fluid channels inside, which are used to induce enhanced particles to pass through the acoustic field to achieve local enrichment and separation of enhanced particles. It contains one inlet and two or more outlets. The height of the middle fluid channel ranges from 15-50μm and the width is 300-800μm. The outlets of the microfluidic chip are directly connected to multiple extruders of the multi-material extrusion system. Interdigital transducers: Two pairs of interdigital transducers are set up, each pair of transducers consists of two groups of metal strips that are staggered and periodically distributed. Each group of electrodes is connected to the bus bar. The two pairs of interdigital transducers can independently generate high-frequency sound waves with a frequency range of 100-310MHz. They can choose to work alone or in coordination, and can be turned on and off in real time as needed. They are located on the lower side of the microfluidic chip. In the initial state, the main axis position of the interdigital transducer is perpendicular to the main axis of the microfluidic chip, and the two pairs of interdigital transducers can be rotated clockwise or counterclockwise at a certain angle as needed, with an angle range of 10-45°; Piezoelectric substrate: When an electric field is applied to the piezoelectric substrate, the substrate deforms due to the inverse piezoelectric effect, thereby generating sound waves. Conversely, when the sound waves propagate to the piezoelectric substrate, charges are generated at both ends of the metal electrodes due to the direct piezoelectric effect, so that another set of interdigital transducers can be used to output alternating electrical signals. Power amplifier: Its function is to enhance the electrical signal generated by the signal generator so that it has enough power to excite the interdigital transducer; Signal generator: The main function of the generator is to generate electrical signals of specific frequency and amplitude, which are then used to excite the interdigital transducer to generate sound waves; Furthermore, the three-dimensional molding platform comprises: UV lamp curing module: It emits ultraviolet light of a specific wavelength to cause a chemical reaction in the photosensitive resin material, thereby curing it quickly. The power is 400-500W; 3D motion hardware system: responsible for controlling the precise movement of the multi-material extrusion system on the three coordinate axes X, Y, and Z. The print head is precisely positioned through the interaction between the stepper motor or servo motor and the slide rail or gear to ensure the accuracy and quality of the printed object. Multi-material extrusion system: Integrates two or more extrusion heads, each of which is directly connected to the outlets of the enhanced particle switching system, and can quickly and accurately deposit the switched composite material system at the corresponding position of the three-dimensional object; Furthermore, the control system comprises: Material delivery control: accurately control the material delivery system to deliver the printing material to be switched to the microfluidic chip of the enhanced particle switching system at a fixed time and speed; Three-dimensional motion control: responsible for controlling the movement of the multi-material extrusion system in three-dimensional space, including precise positioning and movement of the X, Y, and Z axes. The control system needs to be able to generate precise motion paths to ensure that the printed composite structure has the required geometry and dimensional accuracy; Material switching logic: Different types of enhanced particles need to be switched during the printing process. The control system needs to have logic control functions to ensure that the IDT is rotated, switched, and the material is switched at the correct time and position without affecting the printing quality. User interface and software support: Control systems are usually equipped with a user interface that allows the operator to enter printing parameters, select material type, and monitor printing progress.

[0006] A 3D printing method for reinforced particle switchable composite materials: Step 1: Material preparation Matrix material: photosensitive resin precursor material; Reinforced particles: one or more of polystyrene, polymethyl methacrylate, polyamide, polybutylene terephthalate, polypropylene, polyethylene terephthalate, silicon dioxide, aluminum oxide, silicon nitride, titanium boride, boron nitride, and graphite particles; The viscosity of the matrix material is 150 to 900 mPa·s; The reinforced particles have two or more discontinuous particle size distribution ranges, with an overall particle size range of 1-34 μm; Mix 5-20 vol% of the reinforcing particles with the matrix material, stir evenly, and set aside; Step 2: Additive manufacturing of enhanced particle switchable composite materials, specifically including: 1. Material preparation: Mix the matrix material and the reinforcement particles in a predetermined ratio to provide a basic material system for 3D printing with dynamic switching of different material combinations; 2. Design and modeling: Use 3D software to design the structure, create a 3D model, and slice it into printing paths; determine the distribution and switching strategy of the reinforcement particles based on the model to ensure that the equipment can accurately control the material delivery and the switching of the reinforcement particles; When setting the printing parameters: there is a quantitative relationship between the signal frequency of the interdigital transducer and the diameter of the enhanced particles. The smaller diameter enhanced particles correspond to the smaller signal frequency; the larger diameter enhanced particles correspond to the larger signal frequency. The specific parameter settings are as follows: the enhanced particle diameter 1-6μm sets the signal frequency in the range of 100-130MHz; the enhanced particle diameter 6-11μm sets the signal frequency in the range of 130-160MHz; the enhanced particle diameter 11-16μm sets the signal frequency in the range of 160-190MHz; the enhanced particle diameter 16-21μm sets the signal frequency in the range of 190-220MHz; the enhanced particle diameter 21-24μm sets the signal frequency in the range of 220-250MHz; the enhanced particle diameter 24-29μm sets the signal frequency in the range of 250-280MHz; the enhanced particle diameter 29-34μm sets the signal frequency in the range of 280-310MHz; And the input peak voltage of the IDT is closely related to the material conveying speed of the material conveying system. The higher the material conveying speed, the higher the input peak voltage of the IDT. The peak voltage range is 0.7-3.0Vpp. 3. Additive manufacturing process: Start the additive manufacturing equipment and deposit materials according to the preset path and parameters. During the manufacturing process, dynamically switch different combinations of enhanced particles according to design requirements; 4. Post-processing: Use isopropyl alcohol to clean the printed part to remove the residual photosensitive resin on the surface; then, place it under a 300-600W UV lamp for curing for 1-40 minutes.

[0007] The present invention has the following beneficial effects: Innovative integrated microfluidic chip design: Through the microscale fluid channel design inside the microfluidic chip and the independent high-frequency sound waves of the rotatable interdigital transducer to generate sound radiation force, combined with the multi-material extrusion system, an innovative technical solution is provided for the precise control of enhanced particles.

[0008] Dynamic material switching: Combining the enhanced particle switching system with the multi-material extrusion system can dynamically switch different enhanced particle combinations according to design requirements during the printing process, realize material gradient changes and functional integration, and improve the performance and functionality of the printed objects.

[0009] Wide range of material applicability: Applicable to a variety of matrix materials and reinforcing particles, including but not limited to photosensitive resin precursor materials and various types of reinforcing particles such as polystyrene, polymethyl methacrylate, silica, alumina, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Figure 1 It is a schematic diagram of the system configuration of the present invention; Figure 2 It is a top view schematic diagram of the switchable system of enhanced particles in the present invention; Figure 3 It is a material combination mode for inducing the local enrichment of enhanced particles under the action of a single interdigital transducer in the present invention; Figure 4 The present invention uses a switchable system for reinforcing particles to realize a gradual reduction of reinforcing particles from bottom to top inside a three-dimensional sample; Figure 5 It is a material combination mode produced by inducing enhanced local separation of particles under the synergistic action of two pairs of interdigital transducers in the present invention; Figure 6 The invention utilizes a switchable system of reinforcing particles to achieve a distribution of the diameters of the reinforcing particles from bottom to top inside a three-dimensional sample, which is first small, then large, and finally mixed.

[0011] The reference numerals in the figures indicate: 1. Material conveying system, 2. Enhanced particle switching system, 3. Three-dimensional molding platform, 4. Control system; 11. Material supply cylinder, 12. Material supply delivery channel, 21. Microfluidic chip, 22. Interdigital transducer, 23. Piezoelectric substrate, 24. Power amplifier, 25. Signal generator, 31. UV lamp curing module, 32. Three-dimensional motion hardware system, 33. Multi-material extrusion system. DETAILED DESCRIPTION

[0012] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. 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.

[0013] The present invention aims to solve the technical problem that the existing 3D printing technology lacks an effective means for switching enhanced particles. For specific technical solutions, please refer to Figure 1 and Figure 2 As shown, a 3D printing device for reinforced particle switchable composite materials comprises: A material delivery system 1, whose function is mainly to accurately, efficiently and reliably supply raw materials to the enhanced particle switching system 2; The enhanced particle switching system 2, as the core component of the 3D printing device, uses the acoustic radiation force to manipulate the micro-nanoscale enhanced particles in the suspension. This contactless method can achieve precise aggregation and separation of the enhanced particles, thereby dynamically adjusting the local properties of the material during the printing process; The three-dimensional forming platform 3 is used to control the movement of the multi-material extrusion system 32 in three-dimensional space, ensuring that a variety of material systems containing different reinforcing particles can be accurately stacked layer by layer according to a predetermined path to construct a three-dimensional object. This precise control is essential for building complex three-dimensional objects, and it allows the gradient change of materials and functional integration to be achieved during the printing process; Control system 4 ensures that the reinforcing particles in the printing material can be gathered, separated, and switched in real time, and stacked layer by layer along with the matrix material according to a predetermined path. It requires that the control system 4 can accurately control the distribution and movement of the reinforcing particles, as well as coordinate with the three-dimensional molding platform to achieve complex printing designs; The material conveying system 1 comprises: Material supply cylinder 11: used to store printing raw materials, and the outlet is equipped with a control mechanism to ensure that the material can be transported to the enhanced particle switching system 2 at a predetermined rate of 6-83 mm / s and in a predetermined manner; Material supply delivery channel 12: intended to take out the raw material from the supply cylinder and deliver it to the inlet of the microfluidic chip 21 in the enhanced particle switching system 2; The enhanced particle switching system 2 comprises: Microfluidic chip 21: contains a micro-scale fluid channel inside, which is used to induce the enhanced particles to pass through the acoustic field to achieve local enrichment and separation of the enhanced particles. It contains one inlet and two or more outlets. The height of the middle fluid channel ranges from 15 to 50 μm and the width ranges from 300 to 800 μm. The outlets of the microfluidic chip are directly connected to multiple extrusion heads of the multi-material extrusion system 33; Interdigital transducers 22: Two pairs of interdigital transducers 22 are set, each pair of transducers consists of two groups of metal strips that are staggered and periodically distributed. Each group of electrodes is connected to the bus bar. The two pairs of interdigital transducers 22 can independently generate high-frequency sound waves with a frequency range of 100-310MHz. They can choose to work alone or in coordination, and can be turned on and off in real time as needed. They are located on the lower side of the microfluidic chip 21. In the initial state, the main axis position of the interdigital transducer 22 is perpendicular to the main axis of the microfluidic chip. And the two pairs of interdigital transducers 22 can be rotated clockwise or counterclockwise at a certain angle as needed, with an angle range of 10-45°; Piezoelectric substrate 23: When an electric field is applied to the piezoelectric substrate, the substrate is deformed due to the inverse piezoelectric effect, thereby generating sound waves. Conversely, when the sound waves propagate to the piezoelectric substrate, charges are generated at both ends of the metal electrodes due to the direct piezoelectric effect, so that another set of interdigital transducers 22 can be used to output alternating electrical signals; Power amplifier 24: its function is to enhance the electrical signal generated by the signal generator 25 so that it has enough power to excite the interdigital transducer 22; Signal generator 25: The main function of the generator is to generate electrical signals of specific frequency and amplitude, which are then used to excite the interdigital transducer 22 to generate sound waves; The three-dimensional molding platform 3 comprises: UV lamp curing module 31: emits ultraviolet light of a specific wavelength to cause a chemical reaction in the photosensitive resin material, thereby curing it quickly. The power is 400-500W; Three-dimensional motion hardware system 32: responsible for controlling the precise movement of the multi-material extrusion system 32 on the three coordinate axes X, Y, and Z, and accurately positioning the print head through the interaction between the stepper motor or servo motor and the slide rail or gear to ensure the accuracy and quality of the printed object; The multi-material extrusion system 33 integrates two or more extrusion heads, each of which is directly connected to each outlet of the reinforced particle switching system 2, and can quickly and accurately deposit the switched composite material system at the corresponding position of the three-dimensional object; The control system 4 comprises: Material delivery control: accurately control the material delivery system to deliver the printing material to be switched to the microfluidic chip 21 of the enhanced particle switching system 2 at a fixed time and speed; Three-dimensional space motion control: responsible for controlling the motion of the multi-material extrusion system 33 in three-dimensional space, including precise positioning and movement of the X, Y, and Z axes. The control system needs to be able to generate precise motion paths to ensure that the printed composite structure has the required geometric shape and dimensional accuracy; Material switching logic: Different types of reinforcement particles need to be switched during the printing process. The control system needs to have a logic control function to ensure that the IDT 22 rotates, switches, and switches materials at the correct time and position without affecting the printing quality; User interface and software support: Control systems are usually equipped with a user interface that allows the operator to enter printing parameters, select material type, and monitor printing progress.

[0014] A method for 3D printing of reinforced particle switchable composite materials, comprising: Step 1: Material preparation Matrix material: photosensitive resin precursor material; Reinforced particles: one or more of polystyrene, polymethyl methacrylate, polyamide, polybutylene terephthalate, polypropylene, polyethylene terephthalate, silicon dioxide, aluminum oxide, silicon nitride, titanium boride, boron nitride, and graphite particles; The viscosity of the matrix material is 150 to 900 mPa·s; The reinforced particles have two or more discontinuous particle size distribution ranges, and the overall particle size range is 1-34 μm; Mix 5-20 vol% of the reinforcing particles with the matrix material, stir evenly, and set aside; Step 2: Additive manufacturing of enhanced particle switchable composite materials, specifically including: 1. Material preparation: Mix the matrix material and the reinforcement particles in a predetermined ratio to provide a basic material system for 3D printing with dynamic switching of different material combinations; 2. Design and modeling: Use 3D software to design the structure, create a 3D model, and slice it into printing paths; determine the distribution and switching strategy of the reinforcement particles based on the model to ensure that the equipment can accurately control the material delivery and the switching of the reinforcement particles; When setting the printing parameters: there is a quantitative relationship between the signal frequency of the interdigital transducer 22 and the diameter of the enhanced particles. The smaller diameter enhanced particles correspond to the smaller signal frequency, and the larger diameter enhanced particles correspond to the larger signal frequency. The specific parameter settings are as follows: the enhanced particle diameter 1-6μm sets the signal frequency in the range of 100-130MHz; the enhanced particle diameter 6-11μm sets the signal frequency in the range of 130-160MHz; the enhanced particle diameter 11-16μm sets the signal frequency in the range of 160-190MHz; the enhanced particle diameter 16-21μm sets the signal frequency in the range of 190-220MHz; the enhanced particle diameter 21-24μm sets the signal frequency in the range of 220-250MHz; the enhanced particle diameter 24-29μm sets the signal frequency in the range of 250-280MHz; the enhanced particle diameter 29-34μm sets the signal frequency in the range of 280-310MHz; And the input peak voltage of the IDT 22 is closely related to the material conveying speed of the material conveying system 1. The greater the material conveying speed, the higher the input peak voltage of the IDT 22. The peak voltage range is 0.7-3.0Vpp. 3. Additive manufacturing process: Start the additive manufacturing equipment and deposit materials according to the preset path and parameters. During the manufacturing process, dynamically switch different combinations of enhanced particles according to design requirements; 4. Post-processing: Use isopropyl alcohol to clean the printed part to remove the residual photosensitive resin on the surface; then, place it under a 300-600W UV lamp for curing for 1-40 minutes.

[0015] Example 1: Matrix material (90 vol%): photosensitive resin precursor material, with a viscosity of 300 mPa·s; Reinforced particles (10 vol%): polystyrene particles with two particle size distributions, 1-3 μm and 4-6 μm; Mix the two materials evenly and set aside; Use 3D software to design the structure, create a 3D model, and slice it into printing paths; determine the distribution and switching strategy of the reinforcement particles based on the model to ensure that the equipment can accurately control the material delivery and the switching of the reinforcement particles; During the printing process, the left IDT 22 is rotated counterclockwise to make the angle of the IDT 22 θ 1， θ1 is 30°, such as Figure 3 As shown, the signal frequency is 125MHz, the material conveying speed is 50mm / s, and the peak voltage of the interdigital transducer 22 is 0.7Vpp. By adjusting the rotation and switch of the interdigital transducer 22 and combining the real-time switching of the extruder head of the multi-material extrusion system 33, the internal enhancement particles of the three-dimensional sample are gradually reduced from bottom to top, as shown in FIG. Figure 4 Shown After printing, the printed part was cleaned with isopropyl alcohol to remove any residual photosensitive resin on the surface; then, it was placed under a 400W UV lamp for curing for 20 minutes.

[0016] Example 2: Matrix material (80 vol%): photosensitive resin precursor material, with a viscosity of 500 mPa·s; Reinforced particles (20 vol%): Contains two types of reinforced particles, one is polystyrene particles with a particle size range of 1-3 μm; the other is silica particles with a particle size of 10-15 μm; Mix the two materials evenly and set aside.

[0017] During the printing process, the left interdigital transducer 22 is rotated counterclockwise to make the angle of the left interdigital transducer 22 θ 1， θ1 is 30°, and the right IDT 22 is rotated clockwise to make the included angle of the right IDT 22 θ1=30°. 2， θ2 is 30° Figure 5 As shown; the signal frequency of the left IDT 22 is 125MHz, and the signal frequency of the right IDT 22 is 170MHz; the material conveying speed is 70mm / s, and the peak voltage of the IDT 22 is 1.6Vpp. By adjusting the rotation and switch of the IDT 22 and combining the real-time switching of the extruder head of the multi-material extrusion system 33, the distribution of the particle diameter from small to large and finally mixed inside the three-dimensional sample is realized from bottom to top, as shown in FIG. Figure 6 shown.

[0018] After printing, the printed part was cleaned with isopropyl alcohol to remove the residual photosensitive resin on the surface; then, it was placed under a 300W UV lamp for curing for 30 minutes.

Claims

1. A 3D printing device for reinforced particle switchable composite materials, characterized in that: include: A material delivery system (1), whose main function is to accurately, efficiently and reliably supply raw materials to the enhanced particle switching system (2); The reinforcing particle switching system (2), as the core component of the 3D printing device, uses the acoustic radiation force to manipulate the micro-nanoscale reinforcing particles in the suspension. This contactless method can achieve precise aggregation and separation of the reinforcing particles, thereby dynamically adjusting the local properties of the material during the printing process; A three-dimensional molding platform (3) is used to control the movement of a multi-material extrusion system (32) in a three-dimensional space, ensuring that a multi-material system containing different reinforcing particles can be accurately stacked layer by layer along a predetermined path to construct a three-dimensional object. This precise control is essential for constructing complex three-dimensional objects, and it allows for gradient changes in materials and functional integration during the printing process; A control system (4) ensures that the reinforcing particles in the printing material can be aggregated, separated, and switched in real time, and can be stacked layer by layer along a predetermined path with the matrix material. The control system (4) is required to be able to accurately control the distribution and movement of the reinforcing particles, as well as coordinate with the three-dimensional molding platform to achieve complex printing designs; The material conveying system (1) comprises: Material supply cylinder (11): used to store printing raw materials, and the outlet is equipped with a control mechanism to ensure that the material can be delivered to the enhanced particle switching system (2) at a predetermined rate of 6-83 mm / s and in a predetermined manner; Material supply delivery channel (12): is intended to take out the raw material from the supply cylinder and deliver it to the inlet of the microfluidic chip (21) in the enhanced particle switching system (2); The enhanced particle switching system (2) comprises: Microfluidic chip (21): contains a microscale fluid channel inside, which is used to induce the enhanced particles to pass through the acoustic field to achieve local enrichment and separation of the enhanced particles. It contains one inlet and two or more outlets. The height of the middle fluid channel ranges from 15 to 50 μm and the width ranges from 300 to 800 μm. The outlets of the microfluidic chip are directly connected to multiple extrusion heads of the multi-material extrusion system (33). Interdigital transducers (22): Two pairs of interdigital transducers (22) are provided, each pair of transducers is composed of two groups of metal strips that are staggered and periodically distributed, each group of electrodes is connected to a bus bar, and the two pairs of interdigital transducers (22) can independently generate high-frequency sound waves in the frequency range of 100-310 MHz, can be selected to work alone or in coordination, and can be switched on and off in real time as required, and are located on the lower side of the microfluidic chip (21). In the initial state, the main axis position of the interdigital transducers (22) is perpendicular to the main axis of the microfluidic chip, and the two pairs of interdigital transducers (22) can be rotated clockwise or counterclockwise by a certain angle as required, and the angle range is 10-45°; Piezoelectric substrate (23): When an electric field is applied to the piezoelectric substrate, the substrate is deformed due to the inverse piezoelectric effect, thereby generating sound waves. Conversely, when the sound waves propagate to the piezoelectric substrate, charges are generated at both ends of the metal electrodes due to the direct piezoelectric effect, thereby outputting an alternating electric signal using another set of interdigital transducers (22); Power amplifier (24): its function is to enhance the electrical signal generated by the signal generator (25) so that it has sufficient power to excite the interdigital transducer (22); Signal generator (25): The main function of the generator is to generate electrical signals of specific frequency and amplitude, which are then used to excite the interdigital transducer (22) to generate sound waves; The three-dimensional molding platform (3) comprises: UV lamp curing module (31): emits ultraviolet light of a specific wavelength to cause a chemical reaction in the photosensitive resin material, thereby rapidly curing the material. The power is 400-500W; Three-dimensional motion hardware system (32): responsible for controlling the precise movement of the multi-material extrusion system (32) on the three coordinate axes X, Y, and Z, and accurately positioning the print head through the interaction between the stepper motor or servo motor and the slide rail or gear to ensure the accuracy and quality of the printed object; A multi-material extrusion system (33): integrating two or more extrusion heads, each of which is directly connected to each outlet of the reinforced particle switching system (2), and can quickly and accurately deposit the switched composite material system at a corresponding position of the three-dimensional object; The control system (4) comprises: Material delivery control: accurately controlling the material delivery system to deliver the printing material to be switched at a fixed time and speed to the microfluidic chip (21) of the enhanced particle switching system (2); Three-dimensional motion control: responsible for controlling the motion of the multi-material extrusion system (33) in three-dimensional space, including precise positioning and movement of the X, Y, and Z axes. The control system needs to be able to generate precise motion paths to ensure that the printed composite structure has the required geometric shape and dimensional accuracy; Material switching logic: Different types of reinforcement particles need to be switched during the printing process, and the control system needs to have a logic control function to ensure that the IDT (22) is rotated, switched, and the material is switched at the correct time and position without affecting the printing quality; User interface and software support: Control systems are usually equipped with a user interface that allows the operator to enter printing parameters, select material type, and monitor printing progress.

2. A method for 3D printing of reinforced particle switchable composite materials, characterized in that: Using the reinforced particle switchable composite material 3D printing device according to claim 1, the steps include: Step 1: Material preparation Matrix material: photosensitive resin precursor material; Reinforced particles: one or more of polystyrene, polymethyl methacrylate, polyamide, polybutylene terephthalate, polypropylene, polyethylene terephthalate, silicon dioxide, aluminum oxide, silicon nitride, titanium boride, boron nitride, and graphite particles; The viscosity of the matrix material is 150 to 900 mPa·s; The reinforced particles have two or more discontinuous particle size distribution ranges, with an overall particle size range of 1-34 μm; Mix 5-20 vol% of the reinforcing particles with the matrix material, stir evenly, and set aside; Step 2: Additive manufacturing of enhanced particle switchable composite materials, specifically including:

1. Material preparation: Mix the matrix material and the reinforcement particles in a predetermined ratio to provide a basic material system for 3D printing with dynamic switching of different material combinations; 2. Design and modeling: Use 3D software to design the structure, create a 3D model, and slice it into printing paths; determine the distribution and switching strategy of the reinforcement particles based on the model to ensure that the equipment can accurately control the material delivery and the switching of the reinforcement particles; When setting the printing parameters: there is a quantitative relationship between the signal frequency of the interdigital transducer (22) and the diameter of the enhanced particles. The smaller the diameter of the enhanced particles, the smaller the signal frequency. The larger the diameter of the enhanced particles, the larger the signal frequency. The specific parameter settings are as follows: the enhanced particle diameter of 1-6 μm sets the signal frequency in the range of 100-130 MHz; the enhanced particle diameter of 6-11 μm sets the signal frequency in the range of 130-160 MHz; the enhanced particle diameter of 11-16 μm sets the signal frequency in the range of 160-190 MHz; the enhanced particle diameter of 16-21 μm sets the signal frequency in the range of 190-220 MHz; the enhanced particle diameter of 21-24 μm sets the signal frequency in the range of 220-250 MHz; the enhanced particle diameter of 24-29 μm sets the signal frequency in the range of 250-280 MHz; the enhanced particle diameter of 29-34 μm sets the signal frequency in the range of 280-310 MHz. Furthermore, the input peak voltage of the interdigital transducer (22) is closely related to the material conveying speed of the material conveying system (1). The greater the material conveying speed, the higher the input peak voltage of the interdigital transducer (22). The peak voltage range is 0.7-3.0 Vpp.

3. Additive manufacturing process: Start the additive manufacturing equipment and deposit materials according to the preset path and parameters. During the manufacturing process, dynamically switch different combinations of enhanced particles according to design requirements; 4. Post-processing: Use isopropyl alcohol to clean the printed part to remove the residual photosensitive resin on the surface; then, place it under a 300-600W UV lamp for curing for 1-40 minutes.

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