Apparatus for light-cured 3D printing point-plane collaborative exposure and product preparation method

Abstract

The application provides a device for light-cured 3D printing point-surface collaborative exposure and a preparation method of a product. The device comprises a forming table, a printing tank and a light-cured unit. The slurry can be arranged on the printing tank, the forming table can move towards the printing tank to form the slurry, and the light-cured unit can scan the slurry on the printing tank during the forming process. The first light-cured unit and the second light-cured unit act on the slurry in different regions of the printing tank, respectively, and the first light-cured unit and the second light-cured unit can provide at least one of different laser powers, different scanning paths and different scanning speeds to solidify and form the slurry in different regions. The first light-cured unit comprises a reflecting galvanometer and a laser, and the second light-cured unit comprises a DLP light machine. According to the application, the effects of high precision, large format and efficient and rapid 3D printing can be realized simultaneously.

Description

Technical Field

[0001] This invention relates to the field of additive manufacturing ceramic materials technology, specifically to equipment and product preparation methods for photopolymerization 3D printing point-to-surface co-exposure. Background Technology

[0002] The efficient fabrication of high-precision, complex-structured ceramic components with varying properties in different regions of the same ceramic part has created a strong demand in fields such as microelectronics, biomedical engineering, and aerospace. Traditional ceramic fabrication processes are insufficient for this purpose, necessitating new technologies and equipment. Currently, photopolymer 3D printing technology is the most promising technology for producing complex-structured ceramic components. However, previous photopolymer 3D printing equipment mainly focused on point-based stereolithography 3D printing and surface-based digital light processing 3D printing. Stereolithography 3D printing offers high precision and a large printing area, but its fabrication efficiency is low and its time cost is high. Digital light processing 3D printing technology offers fast printing speeds, but its surface finish is poor, making it unable to achieve differentiated fabrication of different regions of the ceramic component.

[0003] Due to the differentiated requirements of the core and shell in the ceramic casting process, existing photopolymerization 3D printing equipment and processes cannot meet the requirements of investment casting for the integrated molding of ceramic core and shell, and cannot simultaneously achieve high-precision and high-efficiency rapid 3D printing effects. Therefore, this invention studies and designs a photopolymerization 3D printing point-surface co-exposure device and product preparation method. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the shortcomings of existing photopolymer 3D printing equipment and processes that cannot meet the requirements of integral molding of different areas of the same product with different internal structures, and cannot simultaneously achieve the effects of high precision and high efficiency and fast 3D printing, thereby providing a device and product preparation method for photopolymer 3D printing point-surface co-exposure.

[0005] To address the aforementioned problems, this invention provides a photopolymerization 3D printing point-surface co-exposure device, comprising: a forming stage, a printing tank, and a photopolymerization unit. Slurry can be placed on the printing tank, and the forming stage can move towards the printing tank to form the slurry. During the forming process, the photopolymerization unit can scan the slurry on the printing tank. There are at least two photopolymerization units, including a first photopolymerization unit and a second photopolymerization unit. The first and second photopolymerization units act on different areas of the slurry on the printing tank, and can provide at least one of different laser powers, different scanning paths, and different scanning speeds to solidify the slurry in different areas. The first photopolymerization unit includes a reflecting mirror and a laser, and the second photopolymerization unit includes a DLP optical engine.

[0006] In some embodiments, the first photocuring unit is an ultraviolet (UV) photocuring unit, the laser is an ultraviolet laser, the ultraviolet laser can emit ultraviolet light to the reflecting mirror, the reflecting mirror can receive the ultraviolet light emitted by the ultraviolet laser and reflect the ultraviolet light onto the paste in the printing tank for three-dimensional exposure of the paste;

[0007] The DLP optical engine can generate and control the intensity of ultraviolet light for surface exposure of the paste.

[0008] In some embodiments, the printing tank includes a first region and a second region. The first photocuring unit is opposite to the first region to scan the slurry on the first region, and the second photocuring unit is opposite to the second region to scan the slurry on the second region. The ceramic material on the first region can be formed into a ceramic core or a ceramic shell by the combined action of the reflecting mirror, the laser, and the forming stage. The ceramic material on the second region can be formed into a ceramic shell or a ceramic core by the combined action of the DLP optical engine and the forming stage.

[0009] In some embodiments, the forming stage is located above the printing tank and can move downwards to act on the slurry on the printing tank to form the slurry, and the photocuring unit is located below the printing tank and can emit light upwards to act on the slurry on the printing tank.

[0010] In some embodiments, a printing support stage lifting drive mechanism is also included, which is supported at the lower end of the forming stage. The printing support stage lifting drive mechanism can drive the forming stage to move up and down, and can control the up and down movement distance and speed of the forming stage.

[0011] The printing tank includes a frame structure, the frame structure has a through groove structure in the middle, the area of ​​the through groove structure can be coated with slurry, and the through groove structure can receive scanning light emitted from the photocuring unit above;

[0012] It also includes a slurry coating system, which is disposed in the through-slot structure of the printing tank to coat the slurry in the through-slot structure and to store the slurry.

[0013] In some embodiments, a frame and a control-display system are also included, wherein the photocuring unit, the printing support stage lifting drive mechanism, and the control-display system are all mounted on the frame, and the control-display system is electrically connected to the printing support stage lifting drive mechanism, the photocuring unit, and the slurry coating system, respectively.

[0014] In some embodiments, the forming stage is located above the printing tank and can move downwards to act on the slurry on the printing tank to form the slurry, and the photocuring unit is located below the printing tank and can emit light upwards to act on the slurry on the printing tank.

[0015] In some embodiments, a printing support stage is also included, which is supported on the lower end and / or side end of the printing groove, and the printing groove includes a frame structure with a through groove structure in the middle of the frame structure, the area of ​​the through groove structure can be coated with slurry, and the through groove structure can receive scanning light emitted from the photocuring unit below.

[0016] It also includes a slurry coating system, which is disposed in the through-slot structure of the printing tank so as to coat the slurry in the through-slot structure and to store the slurry.

[0017] It also includes a molding separation system, which is disposed in the through-slot structure and located above the slurry coating system, so as to separate the molding table from the slurry.

[0018] In some embodiments, the system further includes a frame, an intelligent control-display system, and a printing layer thickness control system. The photocuring unit, the printing support stage, the printing layer thickness control system, and the intelligent control-display system are all mounted on the frame. The forming stage is connected to the printing layer thickness control system, which can control the vertical movement distance and speed of the forming stage. The intelligent control-display system is electrically connected to the printing layer thickness control system, the photocuring unit, and the slurry coating system, respectively.

[0019] This invention also provides a method for preparing photopolymer 3D printed products using multi-performance materials, comprising:

[0020] The stirring and drying step involves mixing and stirring the material powders, followed by drying to obtain a mixed powder.

[0021] The slurry preparation step involves adding the above-mentioned mixed powder to the photocurable resin, heating it to a preset temperature, and then stirring it for a preset time to obtain the photocurable 3D printing slurry.

[0022] The 3D printing integral molding step involves using the aforementioned photopolymer 3D printing point-to-surface co-exposure equipment to print the photopolymer 3D printing paste, thereby obtaining a 3D printed integral blank.

[0023] The degreasing and sintering steps involve degreasing and sintering the 3D printed monolithic blank to obtain a photocurable 3D printed monolithic part.

[0024] The equipment and product preparation method for photopolymer 3D printing point-surface co-exposure provided by this invention have the following beneficial effects:

[0025] This invention utilizes two or more photocuring units, each acting on different areas of the slurry in the printing tank. These units provide varying laser power, scanning paths, and scanning speeds, enabling the slurry in different areas to be cured into different material structures, such as layered structures with varying pore distributions. This allows for the integrated molding of different areas of the same product with different internal structures, such as the integrated molding of cores and shells with differentiated performance requirements, meeting the needs of investment casting for integrated molding of ceramic cores and shells. The simultaneous curing and molding of dual optical paths in photopolymer 3D printing makes printing more efficient. Since the core and shell are formed using the same slurry, the cost and cycle time are greatly reduced. There is no need to change the print head and slurry during the printing process, avoiding the introduction of other impurities in the material, resulting in stable product quality and reliable process. Furthermore, the first photopolymerization unit of this invention, including a reflective galvanometer and a laser, can achieve high-precision stereolithography printing of the product, and the first photopolymerization unit, including a DLP optical engine, can achieve efficient and rapid surface printing of the product. Thus, it can simultaneously achieve the effects of high-precision and efficient and rapid 3D printing. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure of the photopolymerization 3D printing point-surface co-exposure device according to Embodiment 1 of the present invention;

[0027] Figure 2 This is a schematic diagram of the structure of the photopolymerization 3D printing point-surface co-exposure device in Embodiment 2 of the present invention.

[0028] The reference numerals in the attached figures are as follows:

[0029] 1. Frame; 2. Forming table; 3. Slurry coating system; 4. Printing tank; 5. Printing support table lifting drive mechanism; 6. Control-display system; 7. DLP optical engine; 8. Reflecting galvanometer; 9. Laser; 10. Formed body separation system; 11. Printing layer thickness control system; 12. Printing support table; 100. Photocuring unit; 101. First photocuring unit; 102. Second photocuring unit. Detailed Implementation

[0030] like Figure 1-2 As shown, the present invention provides a device for photopolymerization 3D printing point-surface co-exposure, which includes:

[0031] The system comprises a molding stage 2, a printing tank 4, and a photocuring unit 100. Slurry can be placed on the printing tank 4. The molding stage 2 can move towards the printing tank 4 to mold the slurry. During the molding process, the photocuring unit 100 can scan the slurry on the printing tank 4. There are at least two photocuring units 100, including a first photocuring unit 101 and a second photocuring unit 102. The first photocuring unit 101 and the second photocuring unit 102 act on different areas of the slurry on the printing tank 4, and can provide at least one of different laser powers, different scanning paths, and different scanning speeds to cure the slurry in different areas. The first photocuring unit 101 includes a reflecting mirror 8 and a laser 9, and the second photocuring unit 102 includes a DLP optical engine 7.

[0032] DLP optical engine, or digital light processing optical engine, is a scanner that first digitally processes the image signal and then projects the light for scanning.

[0033] This invention utilizes two or more photocuring units, each acting on different areas of the printing tank to cure the slurry, thereby solidifying it into different material structures, such as layered structures with varying pore distributions. This allows for the integrated molding of different areas of the same product with different internal structures, such as cores and shells with differentiated performance requirements, meeting the needs of investment casting for integrated molding of ceramic cores and shells. This invention achieves integrated molding of different areas of the same product with different internal structures, enabling the fabrication of cores and shells with differentiated performance requirements. The simultaneous curing and molding of the dual-light path makes printing more efficient; since the core and shell are formed using the same slurry, the cost and cycle time are greatly reduced; there is no need to change the print head and slurry during the printing process, avoiding the introduction of other impurities in the material, resulting in stable product quality and reliable process; furthermore, the first photopolymerization unit of this invention, including a reflective galvanometer and a laser, can achieve high-precision stereolithography printing (i.e., point exposure) of the product, and the first photopolymerization unit, including a DLP optical engine, can achieve efficient and rapid surface printing (i.e., surface exposure) of the product; thus, it can simultaneously achieve the effects of high-precision and efficient and rapid 3D printing.

[0034] The problem this invention aims to solve is the efficient and high-precision fabrication of complex ceramic components with multiple properties.

[0035] The present invention aims to provide a stereolithography-assisted digital light processing (DLP) photopolymerization 3D printing ceramic equipment and method. The equipment includes: a frame, a forming support stage, a slurry coating system, a printing tank, a printing support stage lifting drive mechanism, an intelligent control-display system, an ultraviolet laser, a reflecting mirror, and a DLP optical engine. The DLP optical engine is mounted directly above or below the frame, and the ultraviolet laser and reflecting mirror are mounted beside the DLP optical engine. The printing support stage lifting drive mechanism is connected to the forming support stage, mounted directly below the frame, and can drive the forming support stage to move precisely up and down. The intelligent control-display system controls the power and movement rate of the ultraviolet laser, reflecting mirror, and printing support stage lifting drive mechanism.

[0036] The working principle of the stereolithography-assisted digital light processing photopolymerization 3D printing ceramic equipment provided by this invention is as follows: An intelligent control-display system controls the DLP optical engine, ultraviolet laser, and reflecting mirror respectively, coordinating two sets of beams to solidify and shape different positions of the ceramic component. This combines the advantages of the ultra-fast forming speed of the DLP optical engine with the ultra-high preparation precision, large-format forming capability, and ease of differentiated preparation of different areas of the ceramic component using stereolithography 3D printing technology. This allows for the calibration and correction of jagged edges on the DLP optical engine forming area by the stereolithography laser beam in the same printing layer, achieving high-precision preparation; high-efficiency preparation is achieved by utilizing the rapid large-area solidification of DLP; the large-format forming capability of stereolithography 3D printing technology greatly expands the printing area, realizing the large-scale printing of the equipment; and differentiated preparation of different areas of the ceramic material is achieved by utilizing stereolithography 3D printing technology for differentiated preparation of different regions.

[0037] In some embodiments, the laser 9 can emit light to the reflecting mirror 8, and the reflecting mirror 8 can receive the light emitted by the laser and reflect the light onto the slurry in the printing tank 4 to form a curing optical path to cure the slurry; the reflecting mirror 8 is arranged in a one-to-one correspondence with the laser 9.

[0038] In some embodiments, the first photocuring unit 101 is an ultraviolet (UV) photocuring unit, and the laser 9 is an UV laser. The UV laser emits UV light to the reflecting mirror 8, which receives the UV light emitted by the UV laser and reflects it onto the slurry in the printing tank 4. This is a further preferred structural form of the photocuring unit of the present invention, namely, a UV laser that emits a UV beam and reflects it onto the slurry in the printing tank through an independent reflecting mirror, thereby achieving rapid and efficient photocuring 3D printing.

[0039] The DLP optical engine of the present invention is preferably installed directly below or above the printing support stage to generate and control the intensity of ultraviolet light and surface exposure of ceramic paste for rapid curing and molding of ceramic materials.

[0040] The ultraviolet laser of the present invention is preferably installed next to the DLP optical engine to generate and control the intensity of ultraviolet light, to calibrate and correct defects caused by insufficient edge accuracy in digital light processing photopolymerization 3D printing, or to widen the printing area of ​​the equipment, or to achieve differentiated molding control of different regions of ceramic materials.

[0041] The reflective galvanometer of the present invention is preferably installed next to the DLP optical engine to control the scanning area and scanning speed of the laser generated by the ultraviolet laser. The angle and angle change speed of the reflective galvanometer are independently controlled by the intelligent controller. It is used to print areas with insufficient edge precision of the digital light processing photopolymerization printing area, or large-format printing areas that cannot be achieved by digital light processing photopolymerization printing, or to control the ultraviolet laser scanning speed and scanning area of ​​different forming areas when realizing multi-performance ceramic materials at different positions of the same component.

[0042] Preferably, the angle between the emitted ultraviolet laser from the reflecting mirror of the present invention and the forming stage is 59°-90°. More preferably, the angle between the forming stage at its maximum forming position during curing of the forming surface and the ultraviolet laser is 59°-90°.

[0043] In some embodiments, the printing tank 4 includes a first region and a second region. The first photocuring unit 101 is opposite to the first region to scan the slurry on the first region, and the second photocuring unit 102 is opposite to the second region to scan the slurry on the second region. Preferably, the slurry is a ceramic material. The ceramic material on the first region can be formed into a ceramic core or a ceramic shell by the combined action of the reflecting mirror 8, the laser 9, and the forming stage 2. The ceramic material on the second region can be formed into a ceramic shell or a ceramic core by the combined action of the DLP optical engine 7 and the forming stage 2.

[0044] This is a further preferred structural relationship between the printing tank and the photocuring unit of the present invention. The printing tank includes first and second regions. The reflecting mirror and laser are opposite to the first region to scan and print the paste on the first region. The DLP optical engine is opposite to the second region to scan and print the paste on the second region. Since at least one of the laser power, scanning path and scanning speed between the first and second photocuring units is different, the internal material and structure of the molded structure of the first and second regions scanned by the first and second photocuring units are also different. For example, the internal pore distribution is different. This effectively achieves the effect of integrally molding different internal structures of different regions on the same structure.

[0045] The printing groove of the present invention is further preferably projected onto a horizontal plane as a rectangular structure, having a long side and a short side, and the first region and the second region are formed at different positions along its long side.

[0046] Furthermore, the slurry of this invention is preferably a ceramic material. Ceramic materials refer to a class of inorganic non-metallic materials made from natural or synthetic compounds through shaping and high-temperature sintering. They possess advantages such as high melting point, high hardness, high wear resistance, and oxidation resistance. They can be used as structural materials and cutting tool materials. Due to certain special properties, ceramics can also be used as functional materials. Specifically, a ceramic core is formed in the first region using a first photocuring unit, and a ceramic shell is formed in the second region using a second photocuring unit, thus completing the integral molding of a ceramic structure with different internal structures (such as different porosities).

[0047] Example 1, such as Figure 1 As shown:

[0048] In some embodiments, the photocuring unit 100 is located above the printing tank 4, and the forming stage 2 is located below the printing tank 4 and can move toward the printing tank 4 to form the slurry.

[0049] The molding stage 2 of this invention is located below the printing tank 4 and can move upwards to act on the slurry on the printing tank 4 to shape the slurry. The photocuring unit 100 is located above the printing tank 4 and can emit light upwards to act on the slurry on the printing tank 4. This is the preferred positional relationship of the molding stage, printing tank, and photocuring unit of this invention. Preferably, the molding stage is located below the printing tank and moves from bottom to top to shape the slurry on the printing tank. After one layer of structure is formed, the molding stage moves from top to bottom to separate from the slurry to scrape the next layer of slurry. Then, the molding stage moves upwards again to form the next layer. Each upward movement of the molding stage completes the formation of one layer of slurry structure. At the same time, the photocuring unit is located above and scans the slurry during the forming process to achieve the effect of single-layer 3D printing.

[0050] In some embodiments, a printing support stage lifting drive mechanism 5 is also included. The printing support stage lifting drive mechanism 5 is supported on the lower end of the forming stage 2. The printing support stage lifting drive mechanism 5 can drive the forming stage 2 to move up and down, and can control the up and down movement distance and speed of the forming stage 2.

[0051] The printing groove 4 includes a frame structure, the frame structure has a through groove structure in the middle, the area of ​​the through groove structure can be coated with slurry, and the through groove structure can receive scanning light emitted from the photocuring unit 100 above.

[0052] It also includes a slurry coating system 3, which is disposed in the through-slot structure of the printing tank 4 to coat the slurry in the through-slot structure and to store the slurry.

[0053] The present invention also utilizes the structure of the printing support stage lifting drive mechanism to effectively support the forming stage and drive the forming stage to move up and down, thereby controlling the distance and speed of its up and down movement, and thus effectively controlling the thickness of the printed single-layer product.

[0054] The printing support stage lifting drive mechanism of the present invention preferably includes a motor, a lead screw and a slider, used to drive the printing support stage to move up and down, so as to ensure the single-layer printing accuracy and the height direction accuracy of the formed parts.

[0055] The printing groove of the present invention is a frame structure that can form an internal through groove structure. The through groove structure can be coated with slurry. The upper part is scanned by light emitted by the photocuring unit, and the lower part is formed by the upward movement of the forming table. Of course, multiple through groove structures are preferred, and supporting ribs can be provided between adjacent through groove structures to effectively support the slurry.

[0056] The present invention also provides slurry to the through-slot structure through a slurry coating system. A layer of slurry is coated in the through-slot structure by scraping. With the upward pressing of the forming table and the scanning of ultraviolet light above, a layer of 3D printed structure is formed. The slurry coating system can also store slurry to provide the slurry required for 3D printing.

[0057] The slurry coating system of the present invention preferably includes a U-shaped double-edged scraper, a motor, a lead screw, and a slider. The "U-shaped" cavity of the U-shaped double-edged scraper is used to store slurry and replenish it on the forming surface through the double blades during the coating process. The motor, lead screw, and slider realize the scraper's back-and-forth constant speed scraping motion.

[0058] In some embodiments, the system also includes a frame 1 and a control-display system 6. The photocuring unit 100, the printing support stage lifting drive mechanism 5, and the control-display system 6 are all mounted on the frame 1. The control-display system 6 is electrically connected to the printing support stage lifting drive mechanism 5, the photocuring unit 100, and the slurry coating system 3, respectively.

[0059] This invention also provides a support frame for the photopolymerization unit, forming stage, printing support stage lifting drive mechanism, and control-display system through the frame. The printing support stage lifting drive mechanism is connected to the forming stage to control the speed and distance of the forming stage movement, thereby controlling the thickness of single-layer and multi-layer printed structures. The control-display system can effectively control the thickness of the printed layers, the scanning speed, scanning power, and the scanning path, as well as the volume of slurry provided by the coating system and the coating speed, etc., effectively completing the intelligent and efficient control of the photopolymerization 3D printing integrated molding equipment.

[0060] The intelligent control-display system includes a data control processor, a display, and an input keyboard, connected to the frame via a hinge. It is connected to the laser, reflecting mirror, support platform lifting drive mechanism, and slurry coating system, independently controlling the on / off state and output power of the DLP optical engine and laser; independently controlling the on-time and power of the DLP optical engine and ultraviolet laser, and the angle and angle change rate of the reflecting mirror; controlling the single-cycle lifting distance and distance compensation of the support platform lifting drive mechanism, and controlling the blade operating speed of the slurry coating system.

[0061] Preferably, the printing power of beams 1 and 2 in this invention is 0-100 nW / cm. 2 ;

[0062] Preferably, the ultraviolet beam scanning speed of the present invention is 0-0.8 m / s;

[0063] Preferably, the scraping speed of the scraper in this invention is 0-0.1 m / s;

[0064] Preferably, the single-layer printing thickness of the present invention is 25-500 μm.

[0065] like Figure 1 As shown, this invention provides a device for stereolithography-assisted digital light processing (DLP) photopolymerization 3D printing of ceramic core-shell integrated molding, comprising: a frame 1, a detachable molding stage 2, a printing tank 4, a printing support stage lifting drive mechanism 5, an intelligent control-display system 6, an independent reflecting mirror 8 (functioning to control the scanning path and scanning speed of the light beam); a laser 9 (preferably an ultraviolet laser); and a slurry coating system 3. The slurry coating system 3, the printing tank 4, and the printing support stage lifting drive mechanism 5 are fixed to the lower part of the frame 1, and the intelligent control-display system 6 is hinged to its outer side. A DLP optical engine 7, an ultraviolet laser 9, and a reflecting mirror 8 are fixed to the upper part of the frame 1, with the ultraviolet laser 9 and reflecting mirror 8 installed next to the DLP optical engine 7. The ultraviolet laser 9 and reflecting mirror 8 are installed directly above the frame 1. The printing support stage lifting drive mechanism 5 is connected to the molding stage 2, installed directly below the frame 1, and can drive the molding stage 2 to move precisely up and down. The intelligent control-display system 6 controls the power and movement speed of the DLP optical engine 7, the ultraviolet laser 9, the reflective mirror 8, and the printing support stage lifting drive mechanism 5.

[0066] Compared with existing technologies, the asynchronous controlled dual-beam multi-performance ceramic material photopolymerization 3D printing equipment and preparation method provided by this invention have the following technical advantages:

[0067] 1. The asynchronous controlled dual-beam multi-performance ceramic material photopolymerization 3D printing equipment provided by this invention includes: a frame, a forming stage, a slurry coating system, a printing tank, a printing support stage lifting drive mechanism, an intelligent control-display system, an ultraviolet laser, a reflecting mirror, and a DLP optical engine. The ultraviolet laser, DLP optical engine, and reflecting mirror are mounted directly above the frame. The printing support stage lifting drive mechanism is connected to the forming stage and mounted directly below the frame, enabling precise up-and-down movement of the forming stage. The intelligent control-display system controls the power and movement rate of the ultraviolet laser, reflecting mirror, and printing support stage lifting drive mechanism.

[0068] 2. The working principle of the asynchronous controlled dual-beam multi-performance ceramic material photopolymerization 3D printing equipment provided by the present invention is as follows: the intelligent control-display system controls the ultraviolet laser, the reflecting galvanometer, and the DLP optical engine respectively, and coordinates the two sets of beams to solidify and form different positions of the ceramic part. By asynchronously controlling the power, scanning speed, and scanning path of the two ultraviolet laser beams, the layered structure, pore-rich areas, and sizes of the ceramic material in different regions are differentiated, thereby realizing the multi-functionality of different regions of the same printing layer.

[0069] 3. Existing multi-material photopolymerization 3D printing methods struggle to print multiple materials on the same printing layer, and multi-material printing requires the preparation of photopolymerization printing pastes for various materials, easily leading to elemental contamination in different printing areas. The method provided by this invention achieves differentiated preparation of multifunctional ceramic materials in different regions of the same sheet using the same paste.

[0070] Example 2, as Figure 2 As shown:

[0071] In some embodiments, the forming stage 2 is located above the printing tank 4 and can move downwards to act on the slurry on the printing tank 4 to form the slurry. The photocuring unit 100 is located below the printing tank 4 and can emit light upwards to act on the slurry on the printing tank 4. This is the preferred positional relationship of the forming stage, printing tank, and photocuring unit of the present invention. Preferably, the forming stage is located above the printing tank and moves from top to bottom to form the slurry on the printing tank. After one layer of structure is formed, the forming stage moves from bottom to top to separate from the slurry to scrape the next layer of slurry. Then, the forming stage moves downwards to form the next layer. Each downward movement of the forming stage completes the formation of one layer of slurry structure. At the same time, the photocuring unit is located below and scans the slurry during the forming process to achieve the effect of single-layer 3D printing.

[0072] In some embodiments, a printing support stage 12 is also included, which is supported on the lower end and / or side end of the printing groove 4. The printing groove 4 includes a frame structure with a through-groove structure in the middle. The area of ​​the through-groove structure can be coated with slurry, and the through-groove structure can receive scanning light emitted from the photocuring unit 100 below. The present invention also utilizes the structure of the printing support stage to effectively support the printing groove. The printing groove is a frame structure that can form an internal through-groove structure. The through-groove structure can be coated with slurry, scanned by light emitted from the photocuring unit below, and shaped by a forming stage moving downwards above. Preferably, there are multiple through-groove structures, and supporting ribs can be provided between adjacent through-groove structures to effectively support the slurry.

[0073] The printing tank of the present invention is preferably a detachable bottomless container. A molding separation system is clamped in the middle of the printing tank by mechanical bolts. The cavity formed by the printing tank and the molding separation system is used to hold the single-layer paste to be printed. Preferably, the angle between the maximum molding position of the molding stage during curing and the ultraviolet laser is 59°-90°.

[0074] In some embodiments, a slurry coating system 3 is also included, which is disposed in the through-slot structure of the printing tank 4 to coat slurry in the through-slot structure and to store slurry. The present invention also enables the slurry coating system to provide slurry to the through-slot structure, coating a layer of slurry in the through-slot structure by scraping. With downward pressing of the forming stage and scanning by ultraviolet light below, a layer of 3D printed structure is formed. The slurry coating system can also store slurry to provide the slurry required for 3D printing.

[0075] The slurry coating system of the present invention preferably includes a U-shaped double-edged scraper, a motor, a lead screw, and a slider. The "U-shaped" cavity of the U-shaped double-edged scraper is used to store slurry and replenish it on the forming surface through the double blades during the coating process. The motor, lead screw, and slider realize the scraper's back-and-forth constant speed scraping motion.

[0076] In some embodiments, a molding separation system 10 is also included. This molding separation system 10 is disposed within the through-slot structure and above the slurry coating system 3 to separate the molding platform 2 from the slurry. Furthermore, by positioning the molding separation system above the slurry coating system, the present invention effectively separates the molding platform from the slurry after the molding platform moves downwards to press the slurry into a single-layer printed structure. This prevents the formed single-layer structure from being lifted or adhering to the molding platform, thus improving the printing effect.

[0077] The molding separation system of the present invention preferably includes a layer of light-transmitting plastic film, which is stretched by the printing groove and the molding is released by the elastic force of the film.

[0078] Preferably, the light-transmitting plastic film of the molding separation system of the present invention is any one of polyethylene, polypropylene, polystyrene, and polyvinyl chloride, with a thickness of 100μm–1000μm.

[0079] In some embodiments, the system further includes a frame 1, an intelligent control-display system 6, and a printing layer thickness control system 11. The photocuring unit 100, the printing support stage 12, the printing layer thickness control system 11, and the intelligent control-display system 6 are all mounted on the frame 1. The forming stage 2 is connected to the printing layer thickness control system 11, which can control the vertical movement distance and speed of the forming stage 2. The intelligent control-display system 6 is electrically connected to the printing layer thickness control system 11, the photocuring unit 100, and the slurry coating system 3, respectively.

[0080] This invention also provides a support frame for the photopolymerization unit, printing support stage, printing layer thickness control system, and intelligent control-display system through the frame. The printing layer thickness control system is connected to the forming stage to control the speed and distance of the forming stage movement, thereby controlling the thickness of single-layer and multi-layer printed structures. The intelligent control-display system can effectively control the thickness of the printed layer, the scanning speed, scanning power, and the changes in the scanning path, as well as control the volume of slurry provided by the coating system and the coating speed, etc., effectively completing the intelligent and efficient control of the photopolymerization 3D printing integrated molding equipment.

[0081] The printing layer thickness control system of the present invention preferably includes a motor, a lead screw, and a slider, which are connected to a slide rail on the back of the frame and can slide up and down along the guide rail to ensure the precise position of the detachable forming stage connected to it and the precise thickness of single-layer printing. The detachable forming stage of the present invention is connected to the printing layer thickness control system, and its bottom plane is parallel to the printing support stage and located directly above the printing groove, for supporting and lifting the photopolymerized parts.

[0082] Preferably, the cumulative control error of the printing layer thickness control system of the present invention in the height direction of the cured part is 0-5μm.

[0083] Preferably, the printing power of beams 1 and 2 in this invention is 0-100 nW / cm. 2 ;

[0084] Preferably, the ultraviolet beam scanning speed of the present invention is 0-0.8 m / s;

[0085] Preferably, the scraping speed of the scraper in this invention is 0-0.1 m / s;

[0086] Preferably, the single-layer printing thickness of the present invention is 25-500 μm.

[0087] The intelligent control-display system includes a data control processor, a display, and an input keyboard, connected to the frame via a hinge. It is connected to the laser, reflecting mirror, support platform lifting drive mechanism, and slurry coating system, independently controlling the laser and DLP optical engine's on / off state and output power; independently controlling the DLP optical engine and ultraviolet laser's on / off time, power level, and the reflecting mirror's angle and angle change rate; independently controlling the support platform lifting drive mechanism's single lifting distance and distance compensation; and controlling the slurry coating system's blade operating speed.

[0088] like Figure 2 As shown, a photopolymer 3D printing device for integral molding of ceramic core and shell includes: a frame 1; a detachable molding stage 2; a printing groove 4; a printing support stage 12; a reflecting mirror 8 (used to control the scanning path and scanning speed of the light beam); a laser 9 (preferably an ultraviolet laser) and a DLP optical engine 7; an intelligent control-display system 6; a slurry coating system 3; a molded body separation system 10; and a printing layer thickness control system 11. The printing slot 4 is fixed to the center of the frame 1 via the printing support platform 12. The molding separation system 10 (using polyethylene film) is tightened and fixed with mechanical bolts through the printing slot 4. The slurry scraping system 3 is installed inside the printing slot 4. A reflecting mirror, laser and DLP optical engine 7 are installed at the bottom of the frame 1 directly below the printing slot 4. The printing layer thickness control system 11 is installed via the slide rail on the back of the frame 1. A detachable molding platform 2 is installed in the movable dovetail groove of the printing layer thickness control system 11 directly above the printing slot 4. The intelligent control-display system 6 is installed on the outside of the frame via a hinge connection and is connected to the reflecting mirror 8, laser 9, DLP optical engine 7, slurry scraping system 3 and printing layer thickness control system 11 via wires. It controls the power, scanning path and scanning speed of the two ultraviolet laser beams, and controls the feeding scraping speed and single-layer printing thickness.

[0089] The printing tank 4 of this invention is an open-bottomed tank with two functions: one is to surround the surrounding slurry, and the other is to hold the separation membrane of the molding separation system 10 in place. The molding separation system 10 separates the molding from the high-transparency glass plate at the bottom of the printing tank 4. The molding separation system 10 is preferably an elastic membrane, which is used to separate the molding from the high-transparency glass plate at the bottom of the printing tank 4 as the molding stage 2 moves upward, taking the membrane with it.

[0090] This invention also provides a preparation step for photopolymerization 3D printing products made of multi-performance materials, comprising:

[0091] The stirring and drying step involves mixing and stirring the material powders, followed by drying to obtain a mixed powder.

[0092] The slurry preparation step involves adding the above-mentioned mixed powder to the photocurable resin, heating it to a preset temperature, and then stirring it for a preset time to obtain the photocurable 3D printing slurry.

[0093] The 3D printing integral molding step involves using the aforementioned photopolymer 3D printing point-to-surface co-exposure equipment to print the photopolymer 3D printing paste, thereby obtaining a 3D printed integral blank.

[0094] The degreasing and sintering steps involve degreasing and sintering the 3D printed monolithic blank to obtain a photocurable 3D printed monolithic part.

[0095] The beneficial effects of the photopolymerization 3D printing ceramic core-shell integrated molding equipment and preparation method provided by the present invention are as follows:

[0096] 1. It achieves simultaneous curing and molding of dual optical paths in photopolymer 3D printing, making printing more efficient;

[0097] 2. Since the ultraviolet laser and the DLP optical mechanism form two ultraviolet curing optical paths, which are independently controlled by an intelligent control-display system, different laser powers, different scanning paths and different scanning speeds can be simultaneously cured and formed in the core and shell areas of the same printing layer. By controlling the layered structure of the pore distribution in different areas through power, scanning path and scanning speed, the integrated molding of core and shell with different performance requirements can be achieved.

[0098] 3. Since the core and shell are made of the same material to achieve their differentiated molding, the cost and cycle are greatly reduced; there is no need to change the print head and paste during the printing process, avoiding the introduction of other impurities in the material, resulting in stable product quality and reliable process.

[0099] The preferred material for this invention is a ceramic material. Specifically, the preparation steps of the multi-performance ceramic material photopolymerization 3D printing ceramic of this invention include the following steps:

[0100] (1) Mix and stir the ceramic powder for 2-3 hours, and then dry to obtain the mixed powder;

[0101] (2) Add the above-obtained mixed powder to the photocurable resin and stir at 80-120℃ for 8-12 hours to obtain photocurable 3D printing ceramic slurry;

[0102] (3) Printing is carried out using a photopolymer 3D printing ceramic core-shell integrated molding equipment. The printing power, printing path and scanning speed of different path segments, scraping speed of the squeegee and the single layer printing thickness of beam 1 and 2 are set so that beam 1 prints the core and beam 2 prints the outer shell structure. The slurry is cured layer by layer by the 3D printing equipment to obtain a photopolymer 3D printed ceramic core-shell integrated blank.

[0103] (4) The photocurable 3D printed ceramic blank obtained in step (3) is degreased and sintered to obtain a photocurable 3D printed ceramic core-shell integrated component;

[0104] The preferred preparation steps and preferred embodiments are as follows:

[0105] The preparation steps of the photopolymer 3D printing differentiated integral ceramic core-shell according to Example 1 of this invention specifically include the following steps:

[0106] (1) Mix and stir the ceramic powder for 2 hours, then dry to obtain the mixed powder;

[0107] (2) The mixed powder obtained above was added to the photocurable resin and stirred at 100°C for 12 hours to obtain photocurable 3D printing ceramic slurry.

[0108] (3) A stereolithography-assisted digital light processing (DLP) photopolymerization 3D printing ceramic machine was used for printing. The printing path of the reflecting galvanometer was set, and the DLP optical engine power was set to 3.5 nW / cm. 2 The printing power of the ultraviolet laser is 45 nW / cm. 2 The scanning speed is 0.5 m / s, the scraping speed is 0.02 m / s, and the single-layer printing thickness is 100 μm. The slurry is cured layer by layer by the 3D printing equipment to obtain a photocurable 3D printed ceramic blank.

[0109] (4) The photocurable 3D printed ceramic blank obtained in step (3) is degreased and sintered to obtain a photocurable 3D printed ceramic part.

[0110] The preparation steps of the photopolymerization 3D printing differentiated integral ceramic core-shell according to Example 2 of this invention specifically include the following steps:

[0111] (1) Mix and stir the ceramic powder for 2 hours, then dry to obtain the mixed powder;

[0112] (2) The mixed powder obtained above was added to the photocurable resin and stirred at 100°C for 12 hours to obtain photocurable 3D printing ceramic slurry.

[0113] (3) A stereolithography-assisted digital light processing (DLP) photopolymerization 3D printing ceramic machine was used for printing. The printing path of the reflecting mirror was set, and the DLP optical engine power was set to 12.5 nW / cm². 2 The printing power of the ultraviolet laser is 58 nW / cm. 2 The scanning speed is 1 m / s, the scraping speed is 0.08 m / s, and the single-layer printing thickness is 300 μm. The slurry is cured layer by layer by the 3D printing equipment to obtain a photocurable 3D printed ceramic blank.

[0114] (4) The photocurable 3D printed ceramic blank obtained in step (3) is degreased and sintered to obtain a photocurable 3D printed ceramic part.

[0115] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention. The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the protection scope of the present invention.

Claims

1. A device for photopolymerization 3D printing of ceramic core-shell integrated molding, characterized in that: include: The device comprises a molding stage (2), a printing tank (4), and a photocuring unit (100). The slurry can be placed on the printing tank (4). The molding stage (2) can move towards the printing tank (4) to mold the slurry. During the molding process, the photocuring unit (100) can scan the slurry on the printing tank (4). There are at least two photocuring units (100), including a first photocuring unit (101) and a second photocuring unit (102). The first photocuring unit (101) and the second photocuring unit (102) act on different areas of the slurry on the printing tank (4), and the first photocuring unit (101) and the second photocuring unit (102) can provide at least one of different laser power, different scanning paths, and different scanning speeds to cure the slurry in different areas. The first photocuring unit (101) includes a reflecting mirror (8) and a laser (9), and the second photocuring unit (102) includes a DLP optical engine (7). The printing tank (4) includes a first region and a second region. The first photocuring unit (101) is opposite to the first region to scan the slurry on the first region. The second photocuring unit (102) is opposite to the second region to scan the slurry on the second region. The slurry is a ceramic material. The ceramic material on the first region can be formed into a ceramic core by the combined action of the reflecting mirror (8), the laser (9) and the forming stage (2). The ceramic material on the second region can be formed into a ceramic shell by the combined action of the DLP optical engine (7) and the forming stage (2). The internal structures of the ceramic core and the ceramic shell are different, and the porosities of the ceramic core and the ceramic shell are different.

2. The equipment for photopolymerization 3D printing of ceramic core-shell integrated molding according to claim 1, characterized in that: The first photocuring unit (101) is an ultraviolet curing unit, and the laser (9) is an ultraviolet laser. The ultraviolet laser can emit ultraviolet light to the reflecting mirror (8), and the reflecting mirror (8) can receive the ultraviolet light emitted by the ultraviolet laser and reflect the ultraviolet light onto the paste in the printing tank (4) for three-dimensional exposure of the paste. The DLP optical engine (7) can generate and control the intensity of ultraviolet light for surface exposure of the paste.

3. The equipment for photopolymerization 3D printing of ceramic core-shell integrated molding according to claim 1, characterized in that: The photocuring unit (100) is located above the printing tank (4), and the forming stage (2) is located below the printing tank (4) and can move toward the printing tank (4) to form the slurry.

4. The equipment for photopolymerization 3D printing of ceramic core-shell integrated molding according to claim 3, characterized in that: It also includes a printing support stage lifting drive mechanism (5), which is supported on the lower end of the forming stage (2). The printing support stage lifting drive mechanism (5) can drive the forming stage (2) to move up and down, and can control the up and down movement distance and speed of the forming stage (2). The printing slot (4) includes a frame structure, the frame structure has a through slot structure in the middle, the area of ​​the through slot structure can be coated with slurry, and the through slot structure can receive scanning light emitted from the photocuring unit (100) above; It also includes a slurry scraping system (3), which is disposed in the through-slot structure of the printing tank (4) so ​​as to scrape slurry in the through-slot structure and to store slurry.

5. The equipment for photopolymerization 3D printing of ceramic core-shell integrated molding according to claim 4, characterized in that: It also includes a frame (1) and a control-display system (6). The photocuring unit (100), the printing support stage lifting drive mechanism (5) and the control-display system (6) are all mounted on the frame (1). The control-display system (6) is electrically connected to the printing support stage lifting drive mechanism (5), the photocuring unit (100) and the slurry coating system (3), respectively.

6. The apparatus for photopolymerization 3D printing of ceramic core-shell integrated molding according to any one of claims 1-5, characterized in that: The forming stage (2) is located above the printing tank (4) and can move downwards to act on the slurry on the printing tank (4) to form the slurry. The photocuring unit (100) is located below the printing tank (4) and can emit light upwards to act on the slurry on the printing tank (4).

7. The equipment for photopolymerization 3D printing of ceramic core-shell integrated molding according to claim 6, characterized in that: It also includes a printing support stage (12), which is supported on the lower end and / or side end of the printing groove (4), and the printing groove (4) includes a frame structure with a through groove structure in the middle of the frame structure. The area of ​​the through groove structure can be coated with slurry, and the through groove structure can receive scanning light emitted from the photocuring unit (100) below. It also includes a slurry scraping system (3), which is disposed in the through-slot structure of the printing tank (4) so ​​as to scrape slurry in the through-slot structure and to store slurry; It also includes a molding separation system (10), which is disposed in the through-slot structure and located above the slurry coating system (3) to separate the molding table (2) from the slurry.

8. The equipment for photopolymerization 3D printing of ceramic core-shell integrated molding according to claim 7, characterized in that: It also includes a frame (1), an intelligent control-display system (6) and a printing layer thickness control system (11). The photocuring unit (100), the printing support stage (12), the printing layer thickness control system (11) and the intelligent control-display system (6) are all mounted on the frame (1). The forming stage (2) is connected to the printing layer thickness control system (11). The printing layer thickness control system (11) can control the vertical movement distance and speed of the forming stage (2). The intelligent control-display system (6) is electrically connected to the printing layer thickness control system (11), the photocuring unit (100) and the slurry coating system (3) respectively.

9. A method for preparing a ceramic core-shell integral molding process by photopolymerization 3D printing of multi-performance materials, characterized in that: include: The stirring and drying step involves mixing and stirring the material powders, followed by drying to obtain a mixed powder. The slurry preparation step involves adding the above-mentioned mixed powder to the photocurable resin, heating it to a preset temperature, and then stirring it for a preset time to obtain the photocurable 3D printing slurry. The 3D printing integral molding step involves using the photopolymer 3D printing ceramic core-shell integral molding equipment as described in any one of claims 1-8 to print the photopolymer 3D printing ceramic slurry to obtain a 3D printed ceramic blank. The degreasing and sintering steps involve degreasing and sintering the 3D printed ceramic blank to obtain a photocurable 3D printed ceramic part.

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