Composite structure preparation system and method for printing by selecting and melting ink through laser

Abstract

The invention relates to the fields of materials, metallurgy, physics, information and the like, in particular to a composite structure preparation system and method for printing by selecting and melting ink through laser. The problems that hierarchical composite integrated construction of multiple functional materials is difficult to achieve and the requirement for lightening and thinning of a metamaterial or metasurface stealth functional structure is difficult to meet through a common technology are solved. Comprising a hardware system and a software control system, the hardware system comprises a laser scanning motion system, a workbench moving system and a dispersion liquid coating system, and the software control system comprises laser scanning motion control, moving table motion control, model layering and scanning path planning, laser parameter control and coating motion control. By means of the selective laser melting ink printing technology, high-precision forming of the metal-based top layer is achieved, the secondary laser scanning and surface polishing functions are achieved, the surface quality of the formed layer can be further improved, and the size precision and consistency are improved.

Description

Technical Field

[0001] The present invention relates to the fields of materials, metallurgy, physics and information, and in particular to a composite structure preparation system and method for laser selected melted ink printing. Background Art

[0002] With the development of high-tech, various radar, infrared detection and other detection technologies are changing with each passing day and electronic information processing technology is increasing. Anti-stealth and high-sensitivity detection technologies are also gradually developing towards complexity and intelligence, and are being used more and more widely in various fields.

[0003] LPChen et al. from Northeastern University studied the preparation of infrared-visible light stealth compatible nanocomposite films to solve the problem that face-centered cubic crystal structure aluminum with infrared stealth characteristics cannot achieve infrared / visible light stealth compatibility. Al-SiO2 nanocomposite films with different SiO2 volume contents were prepared by ultra-high vacuum magnetron sputtering. By adjusting the volume content of SiO2, the preparation of AlSiO2 nanocomposite films with low infrared emissivity and high visible light absorptivity can be achieved, solving the compatibility problem between infrared and visible light stealth. Micro-arc oxidation technology has made certain progress in the preparation of thermal control coatings on the surface of light alloys (titanium alloys, magnesium alloys and aluminum alloys). By preparing micro-arc oxidation electrolytic solutions (adding anions, cations or nano / micron particles) and controlling process parameters (reaction time, current density), the coating absorptivity and emissivity can be controlled. This technology provides an important method for the preparation of thermal control coatings for aerospace, and also provides an important means for the preparation of infrared stealth surface coatings

[11] . Although the research on the design method, preparation process and key technology of nano stealth coating has been continuously deepened, these preparation methods and manufacturing processes still have certain limitations. The equipment of plasma enhanced chemical vapor deposition and magnetron sputtering is expensive and the preparation process is complicated. At the same time, it is difficult to prepare nano stealth coating structure on a large scale due to the limited processing range; the nano stealth coating prepared by sol-gel method has weak bonding with the substrate, poor wear resistance and thermal stability, and is easy to fall off under external load impact; the micro-arc oxidation preparation method requires strict control of parameters such as anode and cathode materials, current, voltage and electrolytic solution concentration, which increases the complexity of the manufacturing process, and the electrolytic waste liquid after manufacturing has a greater impact on the environment.

[0004] Xiong Yijun and others from Central South University also designed a three-layer broadband absorbing metamaterial structure, whose surface and middle layers are periodic array structures with different unit sizes, and the bottom layer is a absorbing flat plate structure. A certain proportion of hydroxyl iron powder and nylon powder are mixed, and the metamaterial absorbing structure is prepared by laser selective sintering SLS process. The research results show that under the condition of vertical incident electromagnetic waves, the metamaterial absorbing structure prepared by SLS has good broadband absorption effect, and achieves more than 90% absorption rate in the frequency range of 4GHz to 18GHz, and has good absorbing performance. Because the laser selective sintering SLS additive manufacturing metamaterial absorbing structure based on powder bed is large in size, the quality of the formed surface is not high, the bonding force with the matrix is ​​relatively weak, and it is difficult to realize the hierarchical composite integration of multiple functional materials, it is difficult to meet the development needs of metamaterials or supersurface stealth functional structures towards lightness, refinement, broadband and multi-band compatibility.

[0005] Therefore, it is urgent to propose a method and system for preparing a stealth / thermal camouflage composite structure based on laser selective melting ink printing to solve the above technical problems. Summary of the invention

[0006] In order to solve the problem that it is difficult to realize the hierarchical composite integrated construction of multiple functional materials due to the common technology, and it is difficult to meet the problem of lightweight and thin metamaterials or metasurface stealth functional structures, the present invention further proposes a composite structure preparation system and method for laser selected melting ink printing.

[0007] The technical solution adopted by the present invention to solve the above problems is:

[0008] The preparation system of the present invention includes a hardware system and a software control system;

[0009] The hardware system includes laser scanning motion system, workbench moving system, and dispersion coating system;

[0010] The software control system includes laser scanning motion control, mobile stage motion control, model layering and scanning path planning, laser parameter control and coating motion control.

[0011] Furthermore: the laser scanning motion system includes a laser, a beam conversion and galvanometer system and a USC-2 control card, and the beam conversion and galvanometer system is controlled by the USC-2 control card.

[0012] Furthermore: the dispersion coating system includes a coating device, a dispersion supply system, and a coating motion system.

[0013] Further: the coating motion system includes a motion controller and a horizontal moving table, and the motion controller controls the movement of the horizontal moving table.

[0014] Further: the dispersed liquid supply system includes a dispersed liquid storage column, a digital I / O control card, a stepper motor driver and a stepper motor. The digital I / O control card and the stepper motor driver drive the stepper motor to supply liquid from the dispersed liquid storage column to the coating device.

[0015] Furthermore: the workbench moving system includes a vertical moving table and a substrate, and the movement of the horizontal moving table and the vertical moving table is controlled by the TCP / IP protocol, thereby realizing the coating movement and the positioning of the substrate.

[0016] The preparation method of the present invention comprises the following steps:

[0017] Step 1: Dispersing 10wt% to 20wt% of polyvinyl pyrrolidone and 40wt% to 50wt% of nano-metal copper powder in 30wt% to 50wt% of a reducing solvent, and performing ultrasonic dispersion and mechanical stirring for about 0.5 to 1 hour to make it uniform, to obtain a metal-based dispersed solution;

[0018] Step 2: Clean the substrate with anhydrous ethanol and dry it after cleaning;

[0019] Step 3: Printing a dielectric layer composed of acrylonitrile-butadiene-styrene with a thickness of 100 to 300 microns using fused deposition modeling;

[0020] Step 4: Fix the substrate on the vertical moving table of the laser selective melting ink printing device;

[0021] Step 5: Load the metal-based nano-dispersed solution into the dispersion storage column, start the coating process using the control system of the device, and evenly coat the dispersion on the surface of the dielectric layer using a coating knife;

[0022] Step 6: Import the 3D model file for printing, and the computer slices, layers and fills the 3D graphics to be printed;

[0023] Step 7: Set the scanning process parameters, and then use the USC-2 laser marking control card 4 based on the XY2-100 galvanometer protocol to achieve laser scanning of the required path, print the microwave diffuse reflection layer, adjust the scanning process parameters to perform secondary laser scanning and polishing on the forming layer to improve the surface quality of the forming layer;

[0024] Step 8: Repeat steps 3 to 6, reset the scanning process parameters, select the printing frequency surface, i.e., the infrared low emissivity layer, adjust the scanning process parameters to perform secondary laser scanning and polishing on the forming layer, and improve the surface quality of the forming layer.

[0025] The beneficial effects of the present invention are:

[0026] The present invention realizes high-precision forming of the top layer of the metal base through laser selective melting ink printing technology;

[0027] The present invention studies parameters such as light field distribution and laser energy density to achieve precise control of melting, solidification and structure in the entire preparation process, greatly improving the dimensional stability and precision of the formed surface.

[0028] The present invention has the functions of secondary laser scanning and surface polishing, which can further improve the surface quality of the forming layer and enhance the dimensional accuracy and consistency;

[0029] The photothermal effect and photocatalytic reaction in the polishing process of the present invention can further regulate the composition and structure of the surface layer, so that the stealth / thermal camouflage performance can be further optimized;

[0030] The present invention is compatible with a variety of metal nanoparticles (such as stainless steel, copper, etc.) and dielectric layers (such as wave-transmitting high-strength glass fiber reinforced plastics, etc.);

[0031] The present invention appropriately regulates the stealth effect of the functional surface by selecting materials. For example, by utilizing the characteristics of nanoparticles, nanomaterials with different functions (such as wave-absorbing nanoparticles and low-emissivity materials) can be flexibly combined.

[0032] Compared with the general preparation process, the present invention has better forming effect and lower preparation cost BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a structural schematic diagram of the preparation system of the present invention;

[0034] Figure 2 It is a flow chart of dispersion configuration;

[0035] Figure 3 is a flow chart of the preparation method of the present invention;

[0036] Figure 4 This is a physical picture of the stealth / thermal camouflage composite structure system described in the present invention.

[0037] Figures 1 to 4 In: 1-laser, 2-beam conversion and galvanometer system, 3-horizontal moving stage, 4-USC-2 control card, 5-motion controller, 6-computer, 7-digital I / O control card, 8-stepper motor, 9-stepper motor driver, 10-dispersion liquid storage column, 11-vertical moving stage, 12-substrate, 13-dispersion liquid, 14-coating knife. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is described below by the specific embodiments shown in the accompanying drawings. However, it should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.

[0039] Specific implementation method 1: Figures 1 to 4 As shown, a composite structure preparation system for laser selection and melting ink printing in this embodiment includes a hardware system and a software control system;

[0040] The hardware system includes laser scanning motion system, workbench moving system, and dispersion coating system;

[0041] The software control system includes laser scanning motion control, mobile stage motion control, model layering and scanning path planning, laser parameter control and coating motion control. Through this highly integrated system, a one-stop solution from design to manufacturing can be achieved, greatly improving the preparation efficiency and performance of composite materials.

[0042] Specific implementation method 2: Figures 1 to 4 As shown, a composite structure preparation system for laser selection and melting ink printing in this embodiment, the laser scanning motion system includes a laser 1, a beam conversion and galvanometer system 2 and a USC-2 control card 4, and the beam conversion and galvanometer system 2 is controlled by the USC-2 control card 4 to achieve high-precision and high-efficiency laser processing, ensuring the accurate melting of materials and the uniform distribution of functional coatings.

[0043] Specific implementation method three: Figures 1 to 4 As shown, the present embodiment is a composite structure preparation system for laser selected melting ink printing, the dispersion coating system includes a coating device, a dispersion supply system, and a coating motion system. By precisely controlling the coating of the dispersion, the functionalization and high performance of the composite material can be achieved.

[0044] Specific implementation method four: Figures 1 to 4 As shown, the present embodiment is a composite structure preparation system for laser selection and melting ink printing, and the coating motion system includes a motion controller 5 and a horizontal moving table 3. The motion controller 5 controls the movement of the horizontal moving table 3 to ensure the performance and quality of the composite material and meet the high-precision and high-reliability manufacturing requirements.

[0045] Specific implementation method five: Figures 1 to 4As shown, a composite structure preparation system for laser selection and melting ink printing in this embodiment, the dispersed liquid supply system includes a dispersed liquid storage column 10, a digital I / O control card 7, a stepper motor driver 9 and a stepper motor 8. The digital I / O control card 7 and the stepper motor driver 9 drive the stepper motor 8 to realize the liquid supply from the dispersed liquid storage column 10 to the coating device, thereby realizing the precise delivery and flow control of the dispersed liquid, which can significantly improve the production efficiency and product quality.

[0046] The coating device is a coating knife 14

[0047] Specific implementation method six: Figures 1 to 4 As shown, a composite structure preparation system for laser selected melting ink printing in this embodiment, the workbench moving system includes a vertical moving table 11 and a substrate 12, and the movement of the horizontal moving table 3 and the vertical moving table 11 is controlled by the TCP / IP protocol, so as to realize the coating movement and the positioning of the substrate 12, thereby improving the flexibility and scalability of the system, and can significantly improve the production efficiency and product quality.

[0048] The control software of the present invention is developed based on Labview software, adopts producer-consumer multithreading mode, combines stepper motor driver 9 and digital I / O control card 7 to control the liquid supply volume and liquid supply speed, and controls the movement of horizontal and vertical moving stages through TCP / IP protocol, thereby realizing coating movement and substrate positioning. The three-dimensional model is sliced ​​and layered by the host computer program, and after the laser scanning parameters are set, the laser scanning of the required path is realized by USC-2 laser marking control card 4 through XY2-100 galvanometer protocol.

[0049] Specific implementation method seven: Figures 1 to 4 As shown, a preparation method of a composite structure preparation system for laser selected melting ink printing in this embodiment includes the following steps:

[0050] Step 1: Dispersing 10wt% to 20wt% of polyvinyl pyrrolidone and 40wt% to 50wt% of nano-metal copper powder in 30wt% to 50wt% of a reducing solvent, and performing ultrasonic dispersion and mechanical stirring for about 0.5 to 1 hour to make it uniform, to obtain a metal-based dispersed solution;

[0051] Step 2: Clean the substrate 12 with anhydrous ethanol and dry it after cleaning;

[0052] Step 3: Printing a dielectric layer composed of acrylonitrile-butadiene-styrene with a thickness of 100 to 300 microns using fused deposition modeling;

[0053] Step 4: Fix the substrate 12 on the vertical moving platform 11 of the laser selective area melting ink printing device;

[0054] Step 5: Load the metal-based nano-dispersed solution into the dispersion storage column 10, start the coating process using the control system of the device, and use the coating knife 14 to evenly coat the dispersion 13 on the surface of the dielectric layer;

[0055] Step 6: Import the 3D model file for printing, and the computer slices, layers and fills the 3D graphics to be printed;

[0056] Step 7: Set the scanning process parameters, and then use the USC-2 laser marking control card 4 based on the XY2-100 galvanometer protocol to achieve laser scanning of the required path, print the microwave diffuse reflection layer, adjust the scanning process parameters to perform secondary laser scanning and polishing on the forming layer to improve the surface quality of the forming layer;

[0057] Step 8: Repeat steps 3 to 6, reset the scanning process parameters, select the printing frequency surface, i.e., the infrared low emissivity layer, adjust the scanning process parameters to perform secondary laser scanning and polishing on the forming layer, and improve the surface quality of the forming layer.

[0058] The present invention uses a pre-configured metal nanoparticle dispersion as a raw material. The dispersion is mixed with a dispersant, a reducing alcohol solution and nanoparticles to form a uniform printing ink, ensuring the distribution stability and uniformity of the material. During the selective melting process of the laser, the precise laser scanning path and power are controlled by a computer to shape the metal-based material into a designed geometric shape, forming a stealth metasurface with specific structural and morphological characteristics. The structural parameters of the microstructure are designed according to actual stealth requirements; during the manufacturing process, after the laser partially melts the material, the molten metal forms a good metallurgical bond with the coating layer, and at the same time, the morphology and dimensional accuracy of the microstructure are ensured by controlling the cooling rate and heat conduction behavior of the molten pool; in addition, the forming effect of the microstructure is optimized by adjusting the laser parameters and the material ratio, thereby improving the effect of controlling the reflection, refraction and absorption characteristics of electromagnetic waves, and achieving absorption or scattering suppression of target microwave signals.

[0059] It should be noted that in the above embodiments, as long as the technical solutions are not contradictory, they can be arranged and combined, and those skilled in the art can exhaust all possibilities based on the mathematical knowledge of arrangement and combination. Therefore, the present invention will no longer describe the technical solutions after arrangement and combination one by one, but it should be understood that the technical solutions after arrangement and combination have been disclosed by the present invention.

[0060] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A composite structure preparation system for laser selection and melting ink printing, characterized in that: Including hardware system and software control system; The hardware system includes laser scanning motion system, workbench moving system, and dispersion coating system; The software control system includes laser scanning motion control, mobile stage motion control, model layering and scanning path planning, laser parameter control and coating motion control.

2. A composite structure preparation system for laser selected melting ink printing according to claim 1, characterized in that: The laser scanning motion system comprises a laser (1), a beam conversion and galvanometer system (2) and a USC-2 control card (4); the beam conversion and galvanometer system (2) is controlled to move via the USC-2 control card (4).

3. The composite structure preparation system for laser selected melting ink printing according to claim 1, characterized in that: The dispersion coating system includes a coating device, a dispersion supply system and a coating motion system.

4. A composite structure preparation system for laser selected melting ink printing according to claim 3, characterized in that: The coating motion system comprises a motion controller (5) and a horizontal moving table (3), and the motion controller (5) controls the movement of the horizontal moving table (3).

5. The composite structure preparation system for laser selected melting ink printing according to claim 3, characterized in that: The dispersed liquid supply system comprises a dispersed liquid storage column (10), a digital I / O control card (7), a stepper motor driver (9) and a stepper motor (8); the digital I / O control card (7) and the stepper motor driver (9) drive the stepper motor (8) to supply liquid from the dispersed liquid storage column (10) to the coating device.

6. The composite structure preparation system for laser selected melting ink printing according to claim 1, characterized in that: The workbench moving system comprises a vertical moving table (11) and a substrate (12), and controls the movement of the horizontal moving table (3) and the vertical moving table (11) through the TCP / IP protocol, thereby achieving coating movement and positioning of the substrate (12).

7. A method for preparing a composite structure preparation system for laser selection and melting ink printing, characterized in that: The steps include: Step 1: Dispersing 10wt% to 20wt% of polyvinyl pyrrolidone and 40wt% to 50wt% of nano-metal copper powder in 30wt% to 50wt% of a reducing solvent, and performing ultrasonic dispersion and mechanical stirring for about 0.5 to 1 hour to make it uniform, to obtain a metal-based dispersed solution; Step 2: Clean the substrate (12) with anhydrous ethanol and dry it after cleaning; Step 3: Printing a dielectric layer composed of acrylonitrile-butadiene-styrene with a thickness of 100 to 300 microns using fused deposition modeling; Step 4: fixing the substrate (12) on the vertical moving platform (11) of the laser selective area melting ink printing device; Step 5: Load the metal-based nano-dispersed solution into the dispersion storage column (10), start the coating process using the control system of the device, and evenly coat the dispersion (13) on the surface of the dielectric layer using a coating knife (14); Step 6: Import the 3D model file for printing, and the computer slices, layers and fills the 3D graphics to be printed; Step 7: Set the scanning process parameters, and then use the USC-2 laser marking control card 4 based on the XY2-100 galvanometer protocol to achieve laser scanning of the required path, print the microwave diffuse reflection layer, adjust the scanning process parameters to perform secondary laser scanning and polishing on the forming layer to improve the surface quality of the forming layer; Step 8: Repeat steps 3 to 6, reset the scanning process parameters, select the printing frequency surface, i.e., the infrared low emissivity layer, adjust the scanning process parameters to perform secondary laser scanning and polishing on the forming layer, and improve the surface quality of the forming layer.

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