3D printing spraying device and method suitable for precise deposition and forming of nano-particles

Abstract

The invention discloses a 3D printing jet device and method suitable for precise deposition and forming of nanoparticles, a sheath flow air inlet channel is arranged on the periphery of a main nozzle, the sheath flow channel and an outlet of the main nozzle are coaxially distributed, and the sheath flow air inlet channel is connected with a sheath flow air source. By adjusting the flow of the sheath flow and the main flow, stable coating airflow can be formed around the aerosol, the main jet airflow is accelerated and focused, and diffusion and splashing of nano-particles can be effectively avoided. And meanwhile, a micro-beam adjustable ultraviolet irradiation module is integrated, local light treatment operation in a deposition beam spot range is carried out, and the printing efficiency is improved. The interior of the main nozzle adopts the design of a multi-stage shrinkage cone structure, and after main airflow enters the nozzle, a stepped acceleration effect is formed; and then converging with sheath gas flow and spraying to finish 3D printing.

Description

Technical Field

[0001] The present invention belongs to the field of micro-nano 3D printing technology, and specifically relates to a 3D printing jet device suitable for the precise deposition and forming of nanoparticles, and also relates to a 3D printing jet method suitable for the precise deposition and forming of nanoparticles. Background Art

[0002] Nanoparticles are the foundation of numerous devices and applications with complex properties and functions. Due to their flexibility and compatibility, nanoparticles have attracted significant research interest in a wide range of fields, including microelectronics, optics, and sensing. However, focusing and deposition of aerosol nanoparticles faces significant challenges related to fundamental properties of nanoparticles, such as their high diffusivity and low inertia. To overcome these key limitations of aerosol nanoparticle beam printing, two approaches have been employed. The first involves aerosol deposition of liquid droplets containing nanoparticles. This approach is similar to droplet inkjet printing, but suffers from the drawbacks of requiring the preparation and storage of nanoparticle-containing inks and the use of solvents during the printing process. The second approach involves dry deposition of nanoparticles onto substrates using aerodynamic lenses or coaxial nozzles. This involves obtaining droplets through spraying, drying, charging, and electromobility separation to distribute the nanoparticle fraction, followed by aerodynamic particle focusing. The most widely used technique is dry aerosol direct writing, which selectively creates nanoparticle patterns on substrates.

[0003] In existing nanoparticle 3D printing devices, the airflow at the nozzle outlet fluctuates dramatically due to complex fluid dynamics. This causes the nanoparticles to be disturbed by unstable aerodynamic forces during the injection process, making the particle trajectory easily deviated. This deviation not only leads to severe beam spot non-uniformity in the deposition area, resulting in a discrete material distribution, but also significantly reduces deposition efficiency, preventing a large number of nanoparticles from being effectively deposited in the target area. This uneven and inefficient deposition beam spot further affects subsequent processing quality, leading to significant performance differences between batches and severely compromising the repeatability and reliability of the process. Several strategies exist for focusing particles, including pneumatic, electrostatic, and electro / thermophoretic focusing. Given the operating principles of dry aerosol direct writing methods and the electrical neutrality of nanoparticles, electrostatic and electro / thermophoretic focusing methods are not optimal for particle focusing in dry aerosol direct writing. Furthermore, traditional single-airflow nozzle structures rely solely on a single airflow to transport and confine nanoparticles. This lack of sufficient control dimensions makes it difficult to precisely guide particles along a predetermined trajectory. Furthermore, the limited confinement of a single airflow cannot effectively suppress jet diffusion, preventing external interference and the fluid's inherent diffusion tendency. This causes the jet to gradually diverge during propagation. This is particularly true in high-speed, compressible jets, where particles are particularly susceptible to shock wave disturbances and shear layer instability. This limitation sharply conflicts with the high-resolution, high-stability deposition requirements of high-precision micro-nano manufacturing, making it difficult to meet the increasingly stringent precision demands placed on nanoparticle jet deposition technology in advanced manufacturing.

[0004] Therefore, developing a nanoparticle 3D printing jet device that can effectively regulate the interaction between sheath flow and main airflow and achieve stable particle transmission and precise deposition has become an urgent problem to be solved in this field. Summary of the Invention

[0005] The purpose of the present invention is to provide a 3D printing jet device suitable for the precise deposition and forming of nanoparticles, aiming to solve the problems of unstable nozzle outlet airflow and low particle deposition rate in the prior art.

[0006] The technical solution adopted by the present invention is a 3D printing jet device suitable for the precise deposition and formation of nanoparticles, comprising a console fixedly connected to an insulating support platform, the console being provided with two stepper motors, the output ends of the two stepper motors being connected to a four-way pipe via a flange, one of the passages formed by the four-way pipe being connected to a 3D printing nozzle in a printing chamber via connected main gas pipelines a and b, and the other being connected to a gas cylinder; the gas cylinder being connected to a sheath gas inlet of the 3D printing nozzle via a sheath gas pipeline; The present invention is also characterized in that: A printing nozzle and a micro-beam adjustable ultraviolet irradiation device are provided in the printing cavity, and the printing nozzle and the micro-beam adjustable ultraviolet irradiation device are fixed to the upper part of the cavity through a V-shaped bracket; the printing nozzle is sealed and connected to the end of the main air path pipe b extending into the cavity through a sealing sleeve.

[0007] A ceramic heating tube is provided in section b of the main gas pipeline, a ceramic heating tube protective sleeve is provided on the outside of the ceramic heating tube, and a section of Laval pipeline is connected to the lower part of the ceramic heating tube. The Laval pipeline has a variable cross-section structure with throat contraction and outlet expansion; the Laval pipeline is connected to the main gas pipeline b through a sleeve reducer.

[0008] The main gas line pipe a is connected to the main gas line pipe b through an elbow tube joint and a tube joint a; the main gas line pipe b is connected to the 3D printing nozzle through a tube joint b, a flange connection plate a, and a V-shaped bracket; The 3D printing nozzle includes a multi-stage convergence cone installed in a detachable shell, and the main gas path pipe b is sealed and connected to the upper part of the multi-stage convergence cone through a sealing gasket; a sheath flow inlet channel is formed between the multi-stage convergence cone and the detachable shell, and the sheath gas in the sheath gas inlet enters the sheath flow inlet channel and merges with the main gas; the end of the detachable shell is a diversion outlet, which is a straight pipe with an inner diameter of 0.15-0.25mm.

[0009] An intermediate cavity is formed inside the four-way tube, and a symmetrically arranged discharge end electrode and a cylindrical electrode are provided inside the intermediate cavity. The two discharge end electrodes are opposite to each other to form a discharge gap; the air inlet connected to the gas cylinder is arranged near the discharge gap position of the two discharge end electrodes.

[0010] The stepper motor is also connected to an input conductive rod, which is provided with an insulating sleeve on the outside. The input conductive rod is a metal conductor, one end of which is connected to an external high-voltage power supply, and the other end of the input conductive rod is connected to a cylindrical electrode, which is connected to the discharge end electrode.

[0011] A spark discharge generator consists of a stepper motor, an intermediate cavity formed by a four-way tube, electrodes, and an external high-voltage power supply. The spark discharge generator's control console includes a high-voltage power supply control module and a stepper motor drive module, which centrally control and adjust the spark discharge energy and conductive rod position.

[0012] The printing chamber includes a chamber, which is provided with a visible chamber door and a control panel. The chamber is provided with a chamber exhaust port, which is connected to an air pump; the visible chamber door is connected to the chamber through a hinge.

[0013] A mass flow controller c is provided on the main gas pipeline a, a mass flow controller a is provided on the sheath gas pipeline, and a mass flow controller b is provided on the pipeline connecting the gas cylinder and the four-way pipeline.

[0014] The micro-beam adjustable ultraviolet irradiation device includes an ultraviolet light source drive motor, which is connected to the focusing tube through a light source connector and a flange connection plate b; the focusing tube is connected to an adjustable aperture group, which is connected to a collimating light guide cover, and an irradiation port is provided at the end of the collimating light guide cover.

[0015] The V-shaped bracket is connected to the detachable shell through a hexagonal cone-end set screw and a nozzle support shell.

[0016] The chamber is also equipped with a lighting lamp, and a movable platform is provided directly below the 3D printing nozzle and the micro-beam adjustable ultraviolet irradiation device, on which a movable printing substrate is provided.

[0017] The second technical solution adopted by the present invention is: a 3D printing jet method suitable for the precise deposition and formation of nanoparticles, which utilizes plasma ablation of two discharge end electrodes to generate nanoparticles, directly mixes inert gas with nanoparticles through a gas cylinder to form an aerosol, and delivers it to the 3D printing nozzle through main gas pipelines a and b. The sheath flow inlet channel on the periphery of the 3D printing nozzle is connected to a sheath flow gas source, and the sheath flow inlet channel is connected to the sheath flow gas source. By adjusting the sheath flow and the mainstream flow rate, a stable enveloping airflow can be formed around the aerosol. A ceramic heating tube is provided in the main gas section to achieve precise heating and control of the main airflow and nanoparticles, accelerate and focus the main jet airflow, and effectively avoid the diffusion and splashing of nanoparticles; an integrated micro-beam adjustable ultraviolet irradiation module performs local light processing operations within the deposition beam spot range to complete the printing operation.

[0018] The beneficial effects of the present invention are: First, the present invention utilizes dry particle deposition, utilizing an inert gas to carry nanoparticles directly into a powder aerosol. In contrast, conventional inkjet printing involves depositing droplets of surfactant-stabilized nanoparticles onto a substrate to form the desired pattern. The use of chemical reagents to stabilize the suspension during nanoparticle synthesis and printing can cause contamination and affect the performance of nanoparticle films. Unlike solvent-based nanoparticle deposition methods, dry techniques do not involve chemical reagents during particle synthesis and deposition, reducing the potential for particle contamination and impurities.

[0019] Second, the focused deposition of nanoparticles (i.e., particles with an aerodynamic diameter less than 100 nanometers) is challenging because they have low inertia and tend to leave the deposition chamber along streamlines without being deposited. Due to the presence of carrier gas and the outlet vacuum environment, a stable enveloping airflow can be formed around the aerosol, which shear-stabilizes the main jet airflow, effectively guiding the nanoparticles to deposit at high speed onto the target substrate, thereby improving deposition efficiency.

[0020] Third, by introducing a Laval nozzle structure into the main airflow, the present invention enables the gas to reach sonic speeds in the throat region and further accelerate to supersonic speeds in the expansion section. This effectively increases the velocity and kinetic energy of nanoparticles entering the nozzle, enhancing particle transport capacity. By adjusting the throat diameter and expansion angle, the Mach number of the main airflow can also be flexibly controlled to adapt to different particle characteristics and process requirements, improving system versatility and aerodynamic efficiency.

[0021] Fourth, the present invention integrates a micro-beam adjustable UV irradiation unit on the side of the nozzle. This irradiation unit has the functions of adjustable beam spot size and variable irradiation direction, which can achieve precise and localized UV treatment of the beam spot area below the nozzle. By controlling the range of the light spot and the irradiation angle, it can match the nanoparticle deposition area, effectively improving the edge clarity of the deposition pattern and the bonding strength between particles. The UV irradiation module is activated during the deposition process and has immediate post-processing capabilities, which helps to enhance the density, adhesion and functional stability of the deposited structure, thereby improving the deposition quality and process accuracy of the nanoparticle printing system.

[0022] Fifth, ceramic heating tubes installed in the main gas path fully preheat the main gas path before entering the nozzle, thereby improving the thermal stability and dynamic performance of the main gas flow. By precisely controlling the heating temperature, the kinetic energy matching between gas and particles is effectively improved, enhancing particle carrying capacity and directional transport. Furthermore, the ceramic heating elements offer excellent thermal stability and corrosion resistance, making them suitable for long-term continuous operation and significantly enhancing the reliability and service life of the device.

[0023] Sixth, the main nozzle adopts a multi-stage convergence cone structure design. When the main airflow enters the nozzle, under the guidance of the first-stage convergence cone, the cross-sectional area of ​​the flow channel gradually decreases, the airflow begins to accelerate and initially realizes the conversion of pressure energy into kinetic energy. As the airflow continues to advance to the subsequent multi-stage convergence cone, each stage of the convergence structure further compresses the airflow, forming a step-by-step acceleration effect. This gradual contraction design avoids the vortex and turbulence caused by the sudden contraction of the airflow, allowing the main airflow to achieve a smooth speed increase and pressure conversion during the injection process. It can not only effectively enhance the airflow's ability to carry nanoparticles, but also ensure that the nanoparticles are sprayed onto the substrate with a more precise trajectory under the action of a stable airflow, thereby improving the beam spot accuracy and deposition rate in the deposition area.

[0024] Seventh, a guide outlet structure is set at the end of the main nozzle outlet cone to effectively avoid the problem of reverse pressure area caused by air flow turbulence. When the airflow carrying nanoparticles is accelerated through the multi-stage contraction cone, if it is directly sprayed into the open space, the airflow will form a backflow due to the sudden change in pressure, forming a reverse pressure area near the nozzle outlet. The reverse airflow in this area will interfere with the normal movement trajectory of the nanoparticles, resulting in uneven dispersion and deposition of particles. The introduction of the guide outlet can guide and constrain the high-speed airflow for a second time, so that the airflow can be ejected from the nozzle in a smooth and stable manner, reducing the turbulent interaction between the airflow and the external environment, eliminating the reverse pressure area, and enabling the airflow to continuously and stably push the nanoparticles to move in the preset direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of the overall structure of the nanoparticle 3D printing injection device of the present invention; In the figure: 1. Support table, 2. Insulating support platform, 3. Control console, 4. Stepper motor, 5. Gas cylinder, 6. Sheath gas pipeline, 7. Mass flow controller a, 8. Mass flow controller b, 9. Mass flow controller c, 10. Intermediate chamber, 11. Main gas pipeline a, 12. Ceramic heating kit, 13. Print chamber, 14. Hinge, 15. Control panel, 16. Visual chamber door, 17. Chamber exhaust port, 18. Air pump.

[0026] Figure 2 This is a schematic diagram of the internal structure of the printing cavity of the nanoparticle 3D printing injection device of the present invention; In the figure: 19. Sealing sleeve, 20. V-shaped bracket, 21. Illumination lamp, 22. 3D printing nozzle, 23. Micro-beam adjustable UV irradiation device, 24. Movable printing substrate.

[0027] Figure 3 (a) is a schematic diagram of the overall structure of the nanoparticle 3D printing nozzle according to the present invention; Figure 3 (b) is a schematic cross-sectional view of the nanoparticle 3D printing nozzle according to the present invention; In the figure: 25. Elbow tube connector, 26. Tube connector a, 27. Tube reducer, 28. Tube connector b, 29. Flange connection plate a, 30. Sheath gas inlet, 31. Removable shell, 32. Main gas line pipe b, 33. Ceramic heating tube, 34. Ceramic heating tube protective sleeve, 35. Laval pipe, 36. Nozzle bracket, 37. Hexagon socket set screw, 38. Sealing gasket, 39. Sealing gasket, 40. Multi-stage contraction cone, 41. Diversion outlet.

[0028] Figure 4 Schematic diagram of the structure of the microbeam adjustable ultraviolet irradiation device of the present invention; In the figure: 42. UV light source drive motor, 43. Light source connector, 44. Flange connection plate b, 45. Focusing tube, 46. Adjustable aperture assembly, 47. Collimating light guide cover, 48. UV irradiation outlet port.

[0029] Figure 5 Schematic diagram of the structure of the spark discharge generator of the present invention; Figure 6 Schematic diagram of the cross section of the intermediate cavity of the present invention; In the figure: 49. Connection end with main gas line, 50. Input conductive rod, 51. Insulating sleeve, 52. Air inlet, 53. Discharge end electrode, 54. Cylindrical electrode, 55. Air outlet.

[0030] Figure 7 Flow chart of the method of the present invention. DETAILED DESCRIPTION

[0031] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0032] Example 1 The present invention is a 3D printing jet device suitable for precise deposition and forming of nanoparticles, which uses a coaxial flow nozzle running at high subsonic speed as a focusing system. Figure 1 The device schematic shown in Figure 3 shows a pneumatic nanoparticle injection device comprising an integrated support, a spark discharge generator, an air system, a nanoparticle 3D printing nozzle, and a microbeam adjustable UV irradiation unit. Nanoparticles are generated by the spark discharge generator and mixed with inert gas from a gas cylinder 5 to form an aerosol. These aerosols are then accelerated through the main airway a11 and the Laval pipe 35 (Figure 3) into the nanoparticle 3D printing nozzle 22, where they are deposited on a movable printing substrate 24. Simultaneously, the integrated microbeam adjustable UV irradiation unit 23 performs localized light treatment within the deposition beam spot.

[0033] Example 2 A 3D printing jet device suitable for precise deposition and forming of nanoparticles includes a console 3 fixedly connected to an insulating support platform 2, wherein the console 3 is provided with two stepper motors 4, and the output ends of the two stepper motors 4 are connected to a four-way pipe via a flange. One of the passages formed by the four-way pipe is connected to the 3D printing nozzle 22 in the printing cavity 13 via the connected main gas pipeline a11 and the main gas pipeline b32, and the other passage is connected to the gas cylinder 5; the gas cylinder 5 is connected to the sheath gas inlet 32 ​​of the 3D printing nozzle 22 via the sheath gas pipeline 6.

[0034] A printing nozzle 22 and a micro-beam adjustable ultraviolet irradiation device 23 are provided in the printing cavity 13, and the printing nozzle 22 and the micro-beam adjustable ultraviolet irradiation device 23 are fixed to the upper part of the cavity through a V-shaped bracket 20; the printing nozzle 22 is sealedly connected to the end of the main air path pipe b32 extending into the cavity through a sealing sleeve 19.

[0035] A ceramic heating tube 33 is provided in the main gas pipeline b32 section, and a ceramic heating tube protective sleeve 34 is provided on the outside of the ceramic heating tube 33. A section of Laval pipe 35 is connected to the lower part of the ceramic heating tube 33. The Laval pipe 35 has a variable cross-section structure with throat contraction and outlet expansion; the Laval pipe 35 is connected to the main gas pipeline b32 through a sleeve reducer 27.

[0036] The main gas pipeline a11 is connected to the main gas pipeline b32 through an elbow sleeve joint 25 and a sleeve joint a26; the main gas pipeline b32 is connected to the 3D printing nozzle 22 through a sleeve joint b28, a flange connection plate a29, and a V-shaped bracket 20; The 3D printing nozzle 22 includes a multi-stage convergence cone 40 installed in a detachable shell 31, and the main air path pipe b32 is sealed and connected to the upper part of the multi-stage convergence cone 40 through a sealing gasket 39; a sheath flow inlet channel is formed between the multi-stage convergence cone 40 and the detachable shell 31, and the sheath gas in the sheath gas inlet 30 enters the sheath flow inlet channel and merges with the main gas; the end of the detachable shell 31 is a guide outlet 41, which is a straight tube with an inner diameter of 0.15-0.25 mm.

[0037] like Figure 6 As shown, an intermediate cavity 10 is formed inside the four-way tube, and a discharge end electrode 53 and a cylindrical electrode 54 are symmetrically arranged inside the intermediate cavity 10. The two discharge end electrodes 53 are opposite to each other to form a discharge gap; the cylindrical electrode 54 is connected to the output end of the stepper motor; the air inlet 52 connected to the gas cylinder 5 is set near the discharge gap position of the two discharge end electrodes 53.

[0038] The stepper motor 4 is also connected to an input conductive rod 50 , and an insulating sleeve 51 is provided on the outside of the input conductive rod 50 ; the input conductive rod 50 is a metal conductor, one end of which is connected to an external high-voltage power supply, and the other end passes through the electrode mounting structure and is connected to the cylindrical electrode 54 .

[0039] The printing chamber 13 includes a chamber, which is provided with a visible chamber door 16 and a control panel 15. The chamber is provided with a chamber exhaust port 17, which is connected to an air pump 18. The visible chamber door 16 is connected to the chamber via a hinge 14. The main gas pipeline a11 is provided with a mass flow controller c9, the sheath gas pipeline 6 is provided with a mass flow controller a7, and the pipeline connecting the gas cylinder 5 and the four-way pipeline is provided with a mass flow controller b8.

[0040] The micro-beam adjustable ultraviolet irradiation device 23 includes an ultraviolet light source driving motor 42, which is connected to a focusing tube 45 through a light source connector 43 and a flange connecting plate b44; the focusing tube 45 is connected to an adjustable aperture group 46, and the adjustable aperture group 46 is connected to a collimating light guide cover 47, and an irradiation port 48 is provided at the end of the collimating light guide cover 47.

[0041] The V-shaped bracket 20 is connected to the detachable housing 31 via a hexagonal cone-end set screw 37 and a nozzle support housing 36 .

[0042] The chamber is further provided with an illumination lamp 21 , and a movable platform is provided directly below the 3D printing nozzle and the micro-beam adjustable ultraviolet irradiation device, on which a movable printing substrate is provided.

[0043] Example 3 On the basis of Example 2, Figure 5As shown, the spark discharge generator ablates the electrode, producing a mixture of electrode material and gas, called aerosol. An insulating support platform 2 is located above the support platform 1, and the two are bolted together, providing structural support for the control console 3. Made of alumina ceramic, it ensures excellent structural stability and electrical insulation. The control console 3 is bolted to the insulating support platform 2 and equipped with a stepper motor 4. This motor 4, coupled to the input conductive rod 50 via a fine-tuning mechanism, drives the rod 50 in axial forward and backward motion, thereby adjusting the discharge gap. The power supply utilizes a pulsed AC power supply, integrating control of the stepper motor 4 and the mass flow controller b8. The motor offers high control precision and can achieve 0.01mm gap adjustment, adapting to varying discharge energies and breakdown distances. The input conductive rod 50 is a cylindrical metal conductor. One end is connected to an external high-voltage power supply, and the other end passes through the electrode mounting structure and connects to the cylindrical electrode 54, enabling the introduction of high-voltage power. An insulating sleeve 51 is provided on the outside of the input conductive rod 50 to prevent breakdown during discharge. The spark discharge generator's central chamber 10 is the core of the device, housing a symmetrically arranged discharge end electrode 53 and cylindrical electrode 54. This chamber serves as a gas guide and provides a sealed environment for the discharge process, creating high-voltage breakdown conditions. The chamber is constructed of non-conductive materials to prevent arc creep. The main gas line connection 49, located on the left side of the spark discharge generator's central chamber 10, is a through-hole. Gas is introduced into the nozzle via an elbow tube fitting 25 in conjunction with a mass flow controller c9. An air inlet 52, located on the right side of the spark discharge generator's central chamber 10, introduces inert gas from a gas cylinder 5 into the chamber and regulates the gas flow in conjunction with a mass flow controller b8. Argon gas supplied through this inlet 52 creates a protective atmosphere in the discharge region, reducing electrode oxidation and particle escape. The discharge end electrode 53 is installed within the spark discharge generator's central chamber 10, located on one side of the electrode gap. The electrode material is preferably a high-melting-point metal to ensure that it does not melt or deform under high temperature and high current. The cylindrical electrode 54 is arranged opposite the discharge end electrode 53, forming a counter-electrode during the discharge process. The electrode has a cylindrical flat-end design and a large power receiving surface, which helps to form a stable plasma channel and prolong the discharge duration. The gas outlet 55 is located at the left end of the intermediate cavity and forms a flow path with the gas inlet 52. The gas and plasma mixture generated during the discharge process enters the 3D printing nozzle 22 through the gas outlet 55 and the main gas path pipe b32.

[0044] Example 4 On the basis of Example 2, Figure 1The print chamber 13 is placed on the support platform 1, with a portion of the chamber positioned within the insulating support platform 2 of the spark discharge generator, effectively saving space. A sealing sleeve 19 is installed between the ferrule connector b28 and the upper portion of the print chamber 13 to ensure a sealed environment. A visual door 16 is mounted on the front of the print chamber via a hinge 14 and can rotate at multiple angles. A sealing strip is installed on the inside of the visual door 16, ensuring real-time visual monitoring of the nanoparticle deposition process within the chamber while maintaining the chamber's airtightness. The visual door is made of a highly transmissive, corrosion-resistant material, offering excellent optical transparency and sealing properties, allowing operators to visually observe the deposition process. A print chamber control panel 15 is located on the left side of the print chamber 13, providing centralized control and operation of the operating environment parameters and auxiliary function modules within the print chamber. This control panel enables real-time adjustment and monitoring of key parameters such as temperature, atmosphere composition, UV radiation, and particle injection status. It also coordinates the operating status of modules such as the nanoparticle nozzle, substrate movement mechanism, heating unit, and exhaust system. An exhaust port 17 is provided on the right side of the printing chamber 13 and is tightly connected to the air pump 18, which is used to achieve rapid replacement of the gas inside the chamber. This exhaust structure can effectively discharge the residual gas, suspended nanoparticles and reaction by-products generated during the printing process in a timely manner, thereby maintaining a clean environment and stable pressure conditions inside the chamber. The air pump 18 can extract and discharge gas periodically or in real time according to the set program to match the working rhythm of the main gas path, sheath gas path and heating component, avoiding airflow turbulence, particle backflow or pollution accumulation. Figure 2 The lighting 21, located inside the print chamber 13, provides stable visible light during the printing process, allowing the operator to observe the working status of the printing area, the material ejection process, and whether the equipment is operating normally in real time, improving visibility and safety. The V-shaped bracket 20 is connected to the upper portion of the print chamber 13 via screws and bolts. The V-shaped structure effectively improves the bracket's overall rigidity and stability, enhancing its support for the nozzle and preventing shaking or displacement during operation.

[0045] Example 5 On the basis of Example 2, as shown in the nanoparticle 3D printing nozzle described in Figure 3, the mixture of nanoparticles and gas phase output at the gas outlet 55 enters the main gas pipeline b32 through the main gas pipeline a11 through the main gas pipeline connection end 49, and an elbow sleeve joint 25 is provided between the main gas pipeline a11 and the main gas pipeline b32, which are connected by internal and external threads. The main gas is transported downward through the main gas pipeline b32. The pipeline is a hollow channel structure, and a ceramic heating tube 33 is provided on the outside of the main gas pipeline, and a ceramic heating tube protective sleeve 34 is provided on the outside thereof, which can realize efficient and stable external heating treatment of the carrier gas in the main gas pipeline. Preheating the gas by the ceramic heating tube can improve the kinetic energy and thermal stability of the gas. The external ceramic protective sleeve can effectively maintain heat, protect against collisions, and isolate external interference, thereby enhancing the safety and service life of the heating structure. It is internally connected to a section of Laval pipe 35, which has a variable cross-section structure with throat contraction and outlet expansion, and is used to achieve acceleration and pressure drop control of the main airflow, realize local supersonic airflow at the nozzle outlet, and improve particle carrying capacity. At the lower end of the main gas path, it is connected to the main nozzle module through a sleeve reducer 27. The internal sleeve structure is convenient for assembly and disassembly, and has both sealing and stability functions. The V-shaped bracket 20 is the supporting frame of the entire lower part of the nozzle and the micro-beam adjustable ultraviolet irradiation device. It is provided with a flange connection plate a29, which is detachably connected by a number of fastening screws. The bracket material is preferably aluminum alloy or high-strength plastic, which has good structural rigidity and thermal conductivity. The removable housing 31 is mounted on the exterior of the nozzle support housing 36 via hexagonal set screws 37. The V-shaped bracket 20 is connected to the multi-step converging cone 40 via internal and external threads. A sealing ring 39 is placed between the multi-step converging cone 40 to ensure an airtight seal within the nozzle. A sealing gasket 38 is placed between the multi-step converging cone 40 and the removable housing 31 to prevent sheath gas leakage and ensure the nozzle's internal tightness. The removable housing 31 allows for replacement of nozzles of varying sizes or angles to accommodate varying flow rates and spray patterns. The sheath gas inlet 30, located on one side of the removable housing 31, connects to an external sheath gas source cylinder 5 and works in conjunction with a mass flow controller a7 to precisely control the sheath gas flow rate. The gas is guided into the nozzle via a sheath gas conduit 6, where it passes through an annular conduit outside the multi-step converging cone 40 and mixes with the main gas flow at the confluence section. This confluence section is designed as a multi-channel integrated area, where flow field guidance achieves coaxial coupling between the main and sheath gas flows, ensuring a stable central jet. Finally, the gas mixture is ejected from the guide outlet 41, completing the accelerated, mixed, and regulated gas and particle transport process for precise deposition on the movable printing substrate 24. By translating or lifting the substrate, in conjunction with the nozzle system, the accuracy, consistency, and repeatability of the deposited pattern are effectively improved, while supporting the layer-by-layer construction of complex graphics and providing key support for high-resolution printing.

[0046] Example 6 On the basis of Example 2, Figure 4 The micro-beam adjustable ultraviolet irradiation device is arranged on the side of the fixed nozzle and mainly includes an ultraviolet light source drive component, a focus adjustment cylinder, an adjustable aperture mechanism and a collimated light output system, which can achieve variable direction of the ultraviolet light beam and controllable spot size. The device can perform high-precision, directional irradiation on the nozzle deposition beam spot area and is suitable for immediate light processing operations during or after deposition. The ultraviolet irradiation device is fixedly mounted on the upper side wall of the V-shaped bracket 20 through the flange connection plate b44 and the light source connection member 43, and its light output direction is toward the deposition beam spot area directly below the nozzle outlet. The ultraviolet light source drive motor 42 is equipped with a micro-stepping motor for linking the rotation of the adjustable aperture component 46 and the focusing cylinder 45 to achieve spot angle and size control. By adjusting the spot range and irradiation angle, the adhesion stability of nanoparticles on the substrate surface and the clarity of the pattern edge can be significantly improved, the density and functional consistency of the deposited structure can be improved, and the molding quality of the deposited pattern at the micro-nano scale can be enhanced. After the nozzle completes a deposition trajectory, the main control system sends a signal to drive the UV light source for a short burst of illumination, enabling simultaneous deposition and illumination. The adjustable aperture assembly 46, controlled by a servo system, supports adjustment of the beam spot diameter from 0.1mm to 3mm to precisely match the deposition beam spot size. The overall illumination path is initially focused by the lens system within the focusing tube 45, then collimated by the collimating light guide 47 before exiting the illumination port 48. The UV light source cable exits through a pre-recorded hole in the flange, ensuring no compromise in nozzle structural stability.

[0047] like Figure 7 As shown, the present invention is applicable to a 3D printing jetting method for precise deposition and forming of nanoparticles, and the specific operation steps are as follows: Step 1: Use plasma to ablate two discharge end electrodes to generate nanoparticles, and use a gas cylinder to mix inert gas with the nanoparticles to form an aerosol; During this process, the inert gas flow rate is adjusted by the mass flow controller b to stably maintain the aerosol concentration; Step 2: The aerosol enters the main gas path and is precisely heated by the ceramic heating tube. The heated aerosol enters the throat of the Laval pipe, reaching sonic speeds and accelerating to supersonic speeds in the expansion section. The sheath gas enters the detachable shell through the sheath gas inlet and merges with the main gas flow to form a stable enveloping gas flow. 3D deposition printing is then carried out after the aerosol passes through the guide outlet. During this process, the sheath gas flow rate is adjusted by the mass flow controller a, and the multi-stage contraction cone effectively suppresses eddies and turbulence by step-by-step acceleration of the main airflow; the straight pipe design of the guide outlet reduces the reverse pressure area, avoids particle dispersion, and guides the aerosol to be precisely deposited and formed on the substrate to complete 3D printing.

[0048] At the same time, the micro-beam adjustable ultraviolet irradiation device is started, the focused light beam matches the deposition beam spot range, and periodic ultraviolet irradiation can enhance the bonding force between particles.

Claims

1. A 3D printing jetting device suitable for precise deposition and forming of nanoparticles, characterized in that: The invention comprises a control console (3) fixedly connected to an insulating support platform (2), wherein the control console (3) is provided with two stepper motors (4), the output ends of the two stepper motors (4) are connected to a four-way pipe via a flange, one of the passages formed by the four-way pipe is connected to a 3D printing nozzle (22) in a printing cavity (13) via a main gas pipeline a (11) and a main gas pipeline b (32) connected thereto, and the other passage is connected to a gas cylinder (5); the gas cylinder (5) is connected to a sheath gas inlet (32) of the 3D printing nozzle (22) via a sheath gas pipeline (6).

2. The 3D printing jetting device suitable for precise deposition and forming of nanoparticles according to claim 1, characterized in that: A printing nozzle (22) and a micro-beam adjustable ultraviolet irradiation device (23) are provided in the printing cavity (13), and the printing nozzle (22) and the micro-beam adjustable ultraviolet irradiation device (23) are fixed to the upper part of the cavity via a V-shaped bracket (20); the printing nozzle (22) is sealedly connected to the end of the main gas path pipe b (12) extending into the cavity via a sealing sleeve (19).

3. The 3D printing jetting device suitable for precise deposition and forming of nanoparticles according to claim 2, characterized in that: A ceramic heating tube (33) is provided in the section b (32) of the main gas line. A ceramic heating tube protective sleeve (34) is provided on the outside of the ceramic heating tube (33). A section of Laval tube (35) is connected to the lower part of the ceramic heating tube (33). The Laval tube (35) has a variable cross-section structure with a throat contraction and an outlet expansion. The Laval tube (35) is connected to the main gas line b (32) via a sleeve reducer (27).

4. The 3D printing jetting device suitable for precise deposition and forming of nanoparticles according to claim 2, characterized in that: The main gas line pipe a (11) is connected to the main gas line pipe b (32) through an elbow sleeve joint (25) and a sleeve joint a (26); the main gas line pipe b (32) is connected to the 3D printing nozzle (22) through a sleeve joint b (28), a flange connection plate a (29), and a V-shaped bracket (20); The 3D printing nozzle (22) includes a multi-stage contraction cone (40) installed in a detachable shell (31), and the main gas path pipe b (32) is sealed and connected to the upper part of the multi-stage contraction cone (40) through a sealing gasket (39); a sheath flow inlet channel is formed between the multi-stage contraction cone (40) and the detachable shell (31), and the sheath gas in the sheath gas inlet (30) enters the sheath flow inlet channel and merges with the main gas; the end of the detachable shell (31) is a guide outlet (41), and the guide outlet (41) is a straight tube with an inner diameter of 0.15-0.25 mm.

5. The 3D printing jetting device suitable for precise deposition and forming of nanoparticles according to claim 2, characterized in that: An intermediate cavity (10) is formed inside the four-way tube, and a symmetrically arranged discharge end electrode (53) and a cylindrical electrode (54) are provided inside the intermediate cavity (10), and the two discharge end electrodes (53) are opposite to each other to form a discharge gap; an air inlet (52) connected to the gas cylinder (5) is provided near the discharge gap position of the two discharge end electrodes (53); The stepper motor (4) is further connected to an input conductive rod (50), and an insulating sleeve (51) is provided on the outside of the input conductive rod (50); the input conductive rod (50) is a metal conductor, one end of which is connected to an external high-voltage power supply, and the other end of which is connected through a cylindrical electrode (54), and the cylindrical electrode (54) is connected to a discharge end electrode (53).

6. The 3D printing jetting device suitable for precise deposition and forming of nanoparticles according to claim 2, characterized in that: The printing chamber (13) comprises a chamber, wherein a visible chamber door (16) and a control panel (15) are provided on the chamber, and a chamber exhaust port (17) is provided on the chamber, wherein the chamber exhaust port (17) is connected to an air pump (18); the visible chamber door (16) is connected to the chamber via a hinge (14).

7. The 3D printing jetting device suitable for precise deposition and forming of nanoparticles according to claim 4, characterized in that: The main gas pipeline a (11) is provided with a mass flow controller c (9), the sheath gas pipeline (6) is provided with a mass flow controller a (7), and the pipeline connecting the gas cylinder (5) and the four-way pipeline is provided with a mass flow controller b (8).

8. The 3D printing jetting device suitable for precise deposition and forming of nanoparticles according to claim 2, characterized in that: The micro-beam adjustable ultraviolet irradiation device (23) comprises an ultraviolet light source drive motor (42), which is connected to a focusing tube (45) via a light source connector (43) and a flange connection plate b (44); the focusing tube (45) is connected to an adjustable aperture group (46), which is connected to a collimating light guide (47), and an irradiation port (48) is provided at the end of the collimating light guide (47).

9. The 3D printing jetting device suitable for precise deposition and forming of nanoparticles according to claim 6, characterized in that: The chamber is also provided with an illumination lamp (21), and a movable platform is provided directly below the 3D printing nozzle and the micro-beam adjustable ultraviolet irradiation device, and a movable printing substrate is provided on the movable platform.

10. A 3D printing jetting method suitable for precise deposition and forming of nanoparticles, characterized in that: The specific steps are as follows: Plasma is used to ablate the two discharge end electrodes to generate nanoparticles. The inert gas and nanoparticles are mixed through a gas cylinder to form an aerosol, which is transported to the 3D printing nozzle through the main gas pipelines a and b. The sheath flow gas source is connected to the sheath flow inlet channel outside the 3D printing nozzle; by adjusting the sheath flow and mainstream flow rates, a stable enveloping airflow is formed around the aerosol. A ceramic heating tube is set in the main gas section to achieve precise heating and control of the main airflow and nanoparticles, accelerate and focus the main jet airflow, and integrate a micro-beam adjustable ultraviolet irradiation module to perform local light processing operations within the deposition beam spot range to complete the printing operation.

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