Multi-material photocuring printer and preparation method of gradient layered structure ceramic material

Abstract

The invention provides a multi-material photocuring printer and a preparation method of a gradient layered structure ceramic material. The multi-material photocuring printer comprises a printing supporting table, a trough structure and a forming platform. Wherein the trough structure comprises a plurality of trough units; each trough unit comprises a slurry trough and a slurry curing area; the slurry tank is used for conveying slurry into the slurry curing area of the same slurry tank unit; a release film is laid at the inner bottom of the slurry curing area; the material groove structure can move on the printing supporting table so that a slurry curing area containing needed slurry can be moved to the printing area. The forming platform is located above the printing supporting table and descends into a slurry curing area located at the printing area in the photocuring printing process, and slurry between the forming platform and the release film is cured under irradiation of the ultraviolet light source system. The multi-material photocuring printer can meet the efficient alternate printing requirement of various ceramic slurries, and preparation of gradient layered structure ceramic materials is achieved.

Description

Technical Field

[0001] This invention relates to the fields of photopolymerization 3D printing technology and high-performance ceramic material preparation technology, and in particular to a multi-material photopolymerization printer and a method for preparing gradient layered ceramic materials. Background Technology

[0002] Photopolymer 3D printing, as an important branch of additive manufacturing, demonstrates significant advantages in the fabrication of high-precision, complex-structured ceramic parts based on its layer-by-layer additive manufacturing principle. However, the intrinsic structure of ceramic materials results in high brittleness and poor fracture toughness, severely limiting their application in impact-resistant environments. With the development of additive manufacturing technology, it has become possible to prepare ceramic materials with alternating layered structures. This structure, by laying ceramic slurries with different material compositions or structures in different printing layers, constructs a biomimetic "brick-and-mortar" multilayer architecture, which can induce repeated deflection and branching of cracks at the interface, thereby consuming more energy and improving the material's damage resistance.

[0003] However, this technology has at least the following key problems in practical applications:

[0004] (1) Traditional single-slot printers cannot meet the demand for efficient alternating printing of various ceramic pastes;

[0005] (2) The lack of precise control over the gradient structure makes it impossible to form an effective stress transition layer.

[0006] In summary, there is an urgent need for a photopolymerization 3D printer to meet the demand for efficient alternating printing of various ceramic slurries, thereby solving the problems of abrupt changes in interlayer performance, low interfacial bonding strength, and inability to achieve continuous gradient changes in material composition and structure caused by printing with a single material in existing photopolymerization 3D printing technology. Summary of the Invention

[0007] In view of this, the present invention provides a multi-material photopolymerization printer and a method for preparing gradient layered ceramic materials. The main purpose is to meet the requirements of efficient alternating printing of various ceramic slurries, so as to realize the preparation of gradient layered ceramic materials.

[0008] To achieve the above objectives, the present invention mainly provides the following technical solutions:

[0009] On one hand, embodiments of the present invention provide a multi-material photopolymerization printer, wherein the multi-material photopolymerization printer includes:

[0010] Printing support stage;

[0011] A material tank structure includes multiple material tank units; each material tank unit includes a slurry tank and a slurry curing area; the slurry tank is used to deliver slurry to the slurry curing area of ​​the same material tank unit; a release film is laid on the inner bottom of the slurry curing area; the material tank structure is movable on the printing support table to move the slurry curing area containing the required slurry to the printing area on the printing support table;

[0012] A forming platform is located above the printing support stage. During the photopolymerization printing process, the platform descends into the slurry curing area located in the printing area and, under the irradiation of an ultraviolet light source system, the slurry between the forming platform and the release film is cured.

[0013] Preferably, a translation drive mechanism is provided on the printing support platform; wherein, the translation drive mechanism is connected to the material tank structure to drive the material tank structure to move on the printing support platform, thereby moving the slurry curing area containing the required slurry to the printing area on the printing support platform;

[0014] Preferably, the translation drive mechanism is a lead screw and slider structure; more preferably, the drive mechanism of the lead screw and slider structure is a linear module or a servo motor.

[0015] Preferably, a scraper is provided between the slurry tank and the slurry curing area in each of the slurry tank units; wherein, by controlling the movement of the scraper, the slurry in the slurry tank is transported to the slurry curing area, and the slurry in the slurry curing area is spread.

[0016] Preferably, the trough structure includes:

[0017] A frame structure having an open inner cavity at the top;

[0018] At least one partition is installed within the frame structure to divide the inner cavity into multiple material trough units; preferably, if there are multiple partitions, the partitions are arranged parallel to each other; the material trough units are arranged parallel to each other.

[0019] A linkage structure is slidably connected to both ends and partitions of the frame structure, used to divide each material tank unit into a slurry tank and a slurry curing area, and can slide along the slurry curing area;

[0020] Preferably, a scraper is provided on the connecting rod structure at each material tank unit position, so that the scraper can be moved by controlling the movement of the connecting rod structure, so that the slurry in the slurry tank is transported to the slurry curing area and the slurry in the slurry curing area is spread.

[0021] Preferably, the scraper is detachably connected to the connecting rod structure to facilitate cleaning, maintenance, and replacement of the scraper; preferably, the detachable nature facilitates the replacement of scrapers with different angles, enabling independent adjustment of the scraper angle;

[0022] Preferably, the scraper is connected to the linkage structure via a height-adjustable mounting mechanism to facilitate adjustment of the vertical gap between the scraper blade and the release film.

[0023] Preferably, the frame structure includes:

[0024] A first frame is connected to a translation drive mechanism on the printing support stage;

[0025] The second frame is superimposed on the first frame;

[0026] A glass plate is placed on the first frame to serve as the inner bottom of the slurry curing area, and the edge of the glass plate is fixed between the first frame and the second frame.

[0027] A release film is laid on the glass plate, and the edge of the release film is fixed between the first frame and the second frame.

[0028] Preferably, the forming platform is a pull-out forming platform; and / or

[0029] A support structure is connected to the printing support platform; wherein a lifting structure is provided on the support structure; wherein the lifting structure can rise or fall along the support structure; the forming platform is connected to the lifting structure, so as to rise or fall relative to the printing area under the action of the lifting structure; and / or

[0030] A light source system is provided in the inner cavity of the printing support stage, and the light source system is located directly below the printing area; and / or

[0031] The number of the material trough units is 2-6; preferably, each material trough unit is an independent and detachable structure; and / or

[0032] The photopolymer 3D printer includes a control system; wherein, the control system is used to control the translation drive mechanism to drive the material tank structure to move, so as to move the slurry curing area containing the required slurry to the printing area on the printing support platform; the control system is used to control the forming platform to descend into the slurry curing area located in the printing area, so that the slurry between the forming platform and the release film is cured under the irradiation of the ultraviolet light source system, and then control the forming platform to rise and separate the cured resin layer from the release film, and then descend again to cure and print the next layer, and so on until the model is completed.

[0033] On the other hand, embodiments of the present invention provide a method for preparing a gradient layered ceramic material, wherein the gradient layered ceramic material is prepared using a multi-material photopolymerization printer as described in any of the above-mentioned embodiments.

[0034] Preferably, the preparation method of the gradient layered ceramic material includes the following steps:

[0035] Slurry loading step: Different types of photocurable ceramic slurries are injected into the slurry tanks of different material tank units on the multi-material photocurable printer;

[0036] Photopolymerization 3D printing steps: Set the printing sequence in the control system of the multi-material photopolymerization printer so as to switch the material tank unit located in the printing area during the photopolymerization printing process according to the printing sequence; then perform photopolymerization 3D printing to obtain a ceramic blank with a composition gradient; preferably, the thickness of a single printed layer is 20-200μm, and the number of consecutive printed layers of the same ceramic material is 3-10 layers.

[0037] Degreasing and sintering treatment: The ceramic blank is subjected to degreasing and sintering treatment to obtain a gradient layered structure ceramic material.

[0038] Preferably, different types of photocurable ceramic slurries exhibit one or more differences in ceramic powder type, ceramic particle size, ceramic fiber content, and reinforcing agent composition; and / or

[0039] Each of the aforementioned photocurable ceramic slurries comprises ceramic powder, photosensitive resin, diluent, photoinitiator, and dispersant; more preferably, each of the aforementioned photocurable ceramic slurries further comprises ceramic fibers and / or reinforcing agents; and / or

[0040] The degreasing treatment is carried out in a protective atmosphere, wherein the temperature of the degreasing treatment is 500-700℃ and the holding time is 120-360 min; and / or

[0041] The sintering process is carried out in a protective atmosphere; wherein the sintering temperature is 1200-1700℃ and the holding time is 120-360min.

[0042] In another aspect, embodiments of the present invention provide a gradient layered ceramic material, wherein the gradient layered ceramic material is prepared by the preparation method of the gradient layered ceramic material described in any one of the above claims;

[0043] Preferably, the flexural strength of the gradient layered ceramic material is not less than 300 MPa, and the fracture toughness is not less than 5.0 MPa·m. 1 / 2 ;

[0044] Preferably, the gradient layered ceramic material exhibits a gradient change in composition and properties in the thickness direction, without macroscopic cracks.

[0045] Compared with the prior art, the multi-material photopolymerization printer and the method for preparing gradient layered ceramic materials of the present invention have at least the following beneficial effects:

[0046] On the one hand, the multi-material photopolymer printer provided in this embodiment, by setting a material tank structure including multiple material tank units on the printing support table, and the material tank structure being movable on the printing support table, allows for the translational switching of material tank units located in the printing area during the printing process, thereby enabling efficient and pollution-free alternating printing of various ceramic slurries. The multi-material photopolymer printer provided in this embodiment breaks through the limitations of traditional single-tank photopolymer printers in terms of material diversity, providing a hardware foundation for the integrated "design-manufacturing" of complex composition gradient ceramic components.

[0047] Furthermore, the multi-material photopolymerization printer provided in this embodiment of the invention, by setting a translation drive mechanism on the printing support platform, and further designing the translation drive mechanism as a lead screw slider structure, can realize the switching and precise positioning of the material trough unit in the printing area.

[0048] Furthermore, the multi-material photopolymer printer provided in this embodiment of the invention designs the material tank structure as an inner cavity frame structure with an open top, and sets at least one partition in the frame structure to divide the inner cavity into multiple material tank units. Further, by setting a connecting rod structure (the connecting rod structure is slidably connected to both ends of the frame structure and the partition), each material tank unit is divided into a slurry tank and a slurry curing area. Furthermore, a scraper is provided below the connecting rod structure at the position of each material tank unit, so that the movement of the connecting rod structure drives the scraper to move, allowing the slurry in the slurry tank to be transported to the slurry curing area and the slurry in the slurry curing area to be spread. It can be seen that the above design of this embodiment achieves a material tank structure design with multiple material tank units in a simple and ingenious way.

[0049] On the other hand, this embodiment provides a method for preparing a gradient layered ceramic material. The method uses the aforementioned multi-material photopolymerization printer to prepare the gradient layered ceramic material, specifically including the following steps: injecting different types of photopolymerization ceramic slurries into different material tank units on the multi-material photopolymerization printer; setting a printing sequence in the control system of the multi-material photopolymerization printer to switch the material tank unit located in the printing area during the photopolymerization printing process; then performing photopolymerization 3D printing to obtain a ceramic blank with a compositional gradient; and performing debinding and sintering treatment on the ceramic blank to obtain the gradient layered ceramic material. The above scheme is explained as follows: This embodiment provides a method for preparing a gradient layered ceramic material. By using a printing strategy of continuous or stepwise changes in composition, a gradient layered structure with smooth performance transition is constructed inside the ceramic material. The solid phase load of the slurry for different material layers is controlled to control the sintering shrinkage of different material layers, and the shrinkage rate of different materials is adjusted to be consistent (specifically, before printing the multi-material layered structure, sintering shrinkage tests are performed on slurries with different solid phase loads for a single component, and the optimal solid phase load for each component slurry is matched according to the test results). This effectively eliminates residual stress concentration caused by abrupt changes in interlayer performance, thereby effectively controlling interlayer cracking of different material layers. In addition, by inducing repeated deflection of cracks at the gradient interface, multi-level energy dissipation is achieved, thereby significantly improving the fracture toughness and interlayer bonding strength of the material.

[0050] Using the multi-material photopolymerization printer and the method for preparing gradient layered ceramic materials provided in this invention, a material with both high flexural strength (≥300MPa) and high fracture toughness (≥5.0MPa·m) was successfully prepared. 1 / 2 Gradient layered ceramics exhibit performance far exceeding that of traditional abrupt interface ceramics, broadening the application prospects of high-performance ceramic materials in extreme environments.

[0051] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings. Attached Figure Description

[0052] Figure 1 This is a schematic diagram of the structure of a multi-material photopolymerization printer provided in an embodiment of the present invention;

[0053] Figure 2 This is a microstructure diagram of the gradient layered ceramic material prepared in Experimental Example 1. Detailed Implementation

[0054] To further illustrate the technical means and effects adopted by the present invention to achieve the intended purpose, the specific embodiments, structures, features, and effects according to the present invention will be described in detail below with reference to the accompanying drawings and preferred embodiments. In the following description, different "embodiments" or "embodiments" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.

[0055] To optimize the interlayer interface bonding and eliminate internal stress caused by abrupt performance changes, this invention designs a multi-material gradient layered structure printing strategy. This design, by constructing gradient regions with continuous transitions in chemical composition, fiber content, or microstructure between adjacent material layers, achieves smooth changes in mechanical properties and thermophysical parameters, significantly alleviates interlayer stress concentration, promotes interlayer interface bonding, and effectively inhibits the initiation and propagation of interfacial cracks. This technology has urgent practical significance and important engineering value for promoting the application of high-strength, high-toughness, and high-reliability ceramic materials in high-end equipment. To realize the above-mentioned multi-material gradient layered structure printing strategy, this invention proposes a photopolymerization 3D printer and a method for preparing gradient layered ceramic materials.

[0056] The present invention will be further described below through specific embodiments:

[0057] Example 1

[0058] This embodiment provides a multi-material photopolymerization printer; wherein, as... Figure 1 As shown, the multi-material photopolymer printer includes a printing support 1, a material tank structure 2, and a forming platform 32. The material tank structure 2 includes multiple material tank units; each material tank unit includes a slurry tank 22 and a slurry curing area 21. The slurry tank 22 is used to deliver slurry into the slurry curing area 21 of the same material tank unit. A release film is laid on the inner bottom of the slurry curing area 21. The material tank structure 2 is movable on the printing support 1 to move the slurry curing area 21 containing the required slurry to the printing area on the printing support 1. The forming platform 32 is located above the printing support 1 and is used to descend into the slurry curing area 21 located at the printing area during the photopolymer printing process, and under the irradiation of the ultraviolet light source system, the slurry between the forming platform 32 and the release film is cured.

[0059] The above-described solution of this embodiment is explained as follows: The multi-material photopolymer printer provided in this embodiment, by setting a material tank structure including multiple material tank units on the printing support 1, and the material tank structure being movable on the printing support 1, allows for the translational switching of material tank units located in the printing area during the printing process, thereby enabling efficient and pollution-free alternating printing of various ceramic slurries. The multi-material photopolymer printer provided in this embodiment breaks through the limitations of traditional single-material tank photopolymer printers in terms of material diversity, providing a hardware foundation for the integrated "design-manufacturing" of complex composition gradient ceramic components.

[0060] Example 2

[0061] This embodiment provides a multi-material photopolymerization printer, which, compared to the previous embodiment, is as follows: Figure 1 As shown, this embodiment is further designed as follows:

[0062] In this embodiment, a translation drive mechanism 11 is provided on the printing support stage 1; wherein, the translation drive mechanism 11 is connected to the material tank structure 2 to drive the material tank structure 2 to move on the printing support stage 1, thereby moving the slurry curing area containing the required slurry to the printing area on the printing support stage 1.

[0063] Preferably, the translation drive mechanism 11 is a lead screw and slider structure. More preferably, the drive mechanism of the lead screw and slider structure is a linear module or a servo motor, with a positioning accuracy better than ±0.1mm.

[0064] It should be noted that the ball screw and slider structure is an integrated high-precision module, mainly composed of a drive motor, ball screw, ball slider, and linear guide. The ball screw is a screw with precision helical grooves machined on its surface, containing balls, and is the core transmission component. The ball slider integrates a ball circulation kit that mates with the threaded grooves of the ball screw. When the screw rotates, the ball slider moves linearly along the screw axis. The linear guide is a rigid guide installed parallel to the ball screw, used to provide linear guidance. The drive between the ball screw and slider structure and the feed trough structure is rigidly connected. Specifically, the first frame at the bottom of the feed trough structure is directly and rigidly fixed to the top mounting plate of the ball slider using bolts or other fasteners.

[0065] Here, the multi-material photopolymerization printer provided in this embodiment of the invention, by setting a translation drive mechanism on the printing support stage 1, and further designing the translation drive mechanism as a lead screw slider structure, can realize the switching and precise positioning of the material trough unit in the printing area.

[0066] Example 3

[0067] This embodiment provides a multi-material photopolymerization printer, which, compared to the above embodiments, is as follows: Figure 1As shown, this embodiment is further designed as follows:

[0068] In this embodiment, a scraper 241 is provided between the slurry tank 22 and the slurry curing area 21 in each slurry tank unit; wherein, by controlling the movement of the scraper 241, the slurry in the slurry tank 22 is transported to the slurry curing area 21, and the slurry in the slurry curing area 21 is spread out.

[0069] Specifically, the material tank structure 2 of this embodiment includes a frame structure, at least one partition 23, and a connecting rod structure 24. The frame structure has an open inner cavity at its upper end. The partition 23 is installed inside the frame structure to divide the inner cavity into multiple material tank units; preferably, if there are multiple partitions 23, they are arranged parallel to each other (the material tank units are arranged parallel to each other). The connecting rod structure 24 is slidably connected to both ends of the frame structure and the partitions 23, dividing each material tank unit into a slurry tank 22 and a slurry curing area 21, and is slidable along the slurry curing area 21.

[0070] Preferably, a scraper 241 is provided below the connecting rod structure 24 at each material tank unit position, so that the scraper can be moved by controlling the movement of the connecting rod structure 24, so that the slurry in the slurry tank 22 is transported to the slurry curing area 22 and the slurry in the slurry curing area 22 is spread.

[0071] Preferably, the scraper is detachably connected to the linkage structure, so that the scraper can be removed for easy cleaning and maintenance, and different angle scrapers can be replaced to achieve independent adjustment of the scraper angle.

[0072] Preferably, the scraper is connected to the linkage structure via a height-adjustable mounting mechanism to facilitate adjustment of the vertical gap between the scraper blade and the release film. Preferably, the mounting mechanism includes an adjusting bracket and a height adjusting assembly; wherein the adjusting bracket is connected to the linkage structure; and the height adjusting assembly (such as a nut assembly) is used to fix the scraper at different height positions on the adjusting bracket, thereby adjusting the vertical gap between the scraper blade and the release film.

[0073] Preferably, the frame structure includes a first frame, a second frame, a glass plate, and a release film; wherein, the first frame is connected to a translation drive mechanism 11 on the printing support stage; the second frame is stacked on the first frame; the glass plate is placed on the first frame to serve as the inner bottom of the slurry curing area, and the edge of the glass plate is fixed between the first frame and the second frame; the release film is laid on the glass plate to serve as the inner bottom of the slurry curing area (the inner bottom of the slurry tank is also composed of a glass plate and a release film laid on it). Preferably, the edge of the release film is fixed between the first frame and the second frame. Preferably, the first frame, the glass plate, the release film, and the second frame are fixed together by fasteners.

[0074] In this embodiment, the material tank structure is designed as a frame structure with an open upper cavity. At least one partition is installed within the frame structure to divide the cavity into multiple material tank units. Furthermore, a connecting rod structure (slidably connected to both ends of the frame structure and the partition) is used to further divide each material tank unit into a slurry tank 22 and a slurry curing area 21. Additionally, a scraper 241 is installed below the connecting rod structure 24 at the location of each material tank unit. By controlling the movement of the connecting rod structure 24, the scraper moves, transporting the slurry in the slurry tank 22 to the slurry curing area 22 and spreading the slurry within the curing area 22. The scraper is detachable for easy cleaning and maintenance, and different angle scrapers can be replaced to achieve independent adjustment of the scraper angle. Therefore, the above design of this embodiment achieves a material tank structure design with multiple material tank units with a simple and ingenious structure.

[0075] Example 4

[0076] This embodiment provides a multi-material photopolymerization printer, which, compared to the above embodiments, is as follows: Figure 1 As shown, this embodiment is further designed as follows:

[0077] The forming platform 32 in this embodiment is a pull-out forming platform. The working principle of the pull-out forming platform for photopolymer printing is as follows: During the photopolymer printing process, the forming platform 32 first descends into the slurry curing area 21 located in the printing area. Ultraviolet light is emitted, passing through the release film in the slurry curing area 21, causing the resin in the gap between the release film and the forming platform to cure. Because the adhesive force between the cured resin layer and the forming platform is greater than the adhesive force between the cured resin layer and the release film, when the forming platform is pulled upwards, the cured resin layer adheres to the forming platform and peels off from the release film. Then, the forming platform descends back into the resin tank, leaving a certain gap with the release film, for the curing of the next layer. This cycle repeats until the final printing is completed. For the photopolymer 3D printer designed in this application, the material tank unit can be switched after each or several layers have cured.

[0078] In addition, a support structure is connected to the printing support stage 1 in this embodiment; wherein, a lifting structure 31 is provided on the support structure; wherein, the lifting structure 31 can rise or fall along the support structure; the forming platform 32 is connected to the lifting structure 31 (the forming platform 32 is connected to the lower side of the lifting structure) so as to rise or fall relative to the printing area under the drive of the lifting structure 31.

[0079] In addition, a light source system 12 is provided in the inner cavity of the printing support stage 1, and the light source system 12 is located directly below the printing area. Above the light source system 12 is the slurry curing area located in the printing area (the bottom of the slurry curing area is a release film).

[0080] In addition, there are 2-6 material trough units, each of which is an independent and detachable structure.

[0081] Additionally, it should be noted that the multi-material photopolymer printer includes a control system. The control system controls the translation drive mechanism to move the material tank structure, moving the slurry curing area containing the required slurry to the printing area on the printing support platform. The control system also controls the forming platform to descend into the slurry curing area located in the printing area. Under the irradiation of the ultraviolet light source system, the slurry between the forming platform and the release film is cured. Then, the forming platform is controlled to rise and separate the cured resin layer from the release film, and then descends again to cure and print the next layer. This cycle continues until the model is complete.

[0082] Example 5

[0083] On the other hand, embodiments of the present invention provide a method for preparing a gradient layered ceramic material, wherein the gradient layered ceramic material is prepared using a multi-material photopolymerization printer as described in any of the above-mentioned embodiments.

[0084] The preparation method of the gradient layered ceramic material includes the following steps:

[0085] Slurry preparation steps: Prepare different types of photocurable ceramic slurries. Each photocurable ceramic slurry includes ceramic powder, photosensitive resin, diluent, photoinitiator, and dispersant; more preferably, each ceramic slurry also includes ceramic fibers and / or reinforcing agents.

[0086] Different types of photocurable ceramic slurries differ in one or more of the following: ceramic powder type, ceramic particle size, ceramic fiber content, and reinforcing agent composition.

[0087] Slurry loading step: Different types of photocurable ceramic slurries are injected into different material tank units on the photocurable 3D printer.

[0088] Photopolymer 3D printing steps: Set the printing sequence in the control system of the photopolymer 3D printer to switch the material tank unit located in the printing area during the photopolymer printing process; then perform photopolymer 3D printing to obtain a ceramic blank with a composition gradient.

[0089] Degreasing and sintering treatment: The ceramic blank is subjected to degreasing and sintering treatment to obtain a gradient layered structure ceramic material.

[0090] The degreasing process is carried out in a protective atmosphere, wherein the temperature of the degreasing process is 500-700℃ and the holding time is 120-360min.

[0091] The sintering process is carried out in a protective atmosphere; wherein the sintering temperature is 1200-1700℃ and the holding time is 120-360min.

[0092] Here, this embodiment provides a method for preparing a gradient layered ceramic material. By designing a gradient stress release and toughening mechanism, "a printing strategy with continuous or stepwise changes in composition is used to construct a gradient layered structure with smooth performance transition inside the ceramic material." This effectively eliminates residual stress concentration caused by abrupt changes in interlayer properties and achieves multi-level energy dissipation by inducing cracks to repeatedly deflect at the gradient interface, thereby significantly improving the fracture toughness and interlayer bonding strength of the material.

[0093] The present invention will be further illustrated below through specific experimental examples:

[0094] Experimental Example 1

[0095] Example 1 of this experiment uses the multi-material photopolymerization printer described in the above example to prepare an Al2O3-ZrO2 gradient layered ceramic material; specifically, it includes the following steps:

[0096] Step 1), prepare three different photocurable ceramic slurries:

[0097] Photocurable ceramic slurry A (solid phase without ZrO2): Weigh 80 parts by weight of Al2O3 ceramic powder (particle size 0.5μm), 20 parts by weight of photosensitive resin (trimethylolpropane triacrylate), 0.5 parts by weight of photoinitiator 819, and 1 part by weight of dispersant BYK9076. Add the weighed materials to a planetary ball mill and ball mill at 300 rpm for 240 min to obtain a uniform slurry with a viscosity of approximately 1200 mPa·s.

[0098] Photocurable ceramic slurry B (solid phase containing 20% ​​ZrO2): Weigh 64 parts by weight of Al2O3 powder, 16 parts by weight of ZrO2 powder (particle size 0.5 μm), 20 parts by weight of photosensitive resin (trimethylolpropane triacrylate), 0.5 parts by weight of photoinitiator 819, and 1 part by weight of dispersant BYK9076. Add the weighed materials to a planetary ball mill and ball mill at 300 rpm for 240 min to obtain a uniform slurry with a viscosity of approximately 1350 mPa·s.

[0099] Photocurable ceramic slurry C (solid phase containing 40% ZrO2): Weigh 48 parts by weight of Al2O3 powder, 32 parts by weight of ZrO2 powder, 20 parts by weight of photosensitive resin (trimethylolpropane triacrylate), 0.5 parts by weight of photoinitiator 819, and 1 part by weight of dispersant BYK9076. Add the weighed materials to a planetary ball mill and ball mill at 300 rpm for 240 min to obtain a uniform slurry with a viscosity of approximately 1620 mPa·s.

[0100] Step 2) Inject UV-curable ceramic slurry A, UV-curable ceramic slurry B, and UV-curable ceramic slurry C into the three slurry tanks of the UV-curable printer, respectively. Design a cuboid ceramic model (40mm × 10mm × 4mm). In the slicing software, set the gradient printing sequence: layers 1-5 use UV-curable ceramic slurry A, layers 6-10 use UV-curable ceramic slurry B, layers 11-15 use UV-curable ceramic slurry C, layers 16-20 use slurry B, layers 21-25 use slurry A, and so on, forming a symmetrical gradient structure. Set the printing parameters: laser power 300mW, scanning speed 6000mm / s, single layer thickness 50μm. During the printing process, the printer automatically switches the slurry tanks to complete the preparation of the ceramic green body.

[0101] Step 3) The ceramic blank is placed in a muffle furnace for degreasing treatment. The process parameters for degreasing treatment are: heating rate of 15℃ / h; degreasing treatment temperature of 600℃; and holding time at the degreasing treatment temperature of 3 hours.

[0102] Step 4): The degreased ceramic blank is placed in a high-temperature sintering furnace for sintering and then naturally cooled to room temperature to obtain an Al2O3-ZrO2 gradient layered ceramic material. The sintering process parameters are: heating rate of 10℃ / min; sintering temperature of 1650℃; and holding time at the sintering temperature of 3 hours.

[0103] Microstructure diagram of the gradient layered ceramic material prepared in Experimental Example 1, see [link / reference]. Figure 2 As shown, from Figure 2It can be seen that Al and Zr elements exhibit a clear gradient transition distribution in the printing direction, which indicates that the photopolymerization 3D printer described in this invention can accurately prepare multi-material gradient transition layered structures.

[0104] Experimental Example 2

[0105] This experimental embodiment uses the multi-material photopolymerization printer described in the above embodiment to prepare an asymmetric Al2O3-ZrO2 gradient layered ceramic material. Specifically, it includes the following steps:

[0106] Step 1): Prepare three different light-curing ceramic slurries:

[0107] Photocurable ceramic slurry A (solid phase without ZrO2): Weigh 80 parts by weight of Al2O3 ceramic powder (particle size 0.5μm), 20 parts by weight of photosensitive resin (trimethylolpropane triacrylate), 0.5 parts by weight of photoinitiator 819, and 1 part by weight of dispersant BYK9076. Add the weighed materials to a planetary ball mill and ball mill at 300 rpm for 240 min to obtain a uniform slurry with a viscosity of approximately 1200 mPa·s.

[0108] Photocurable ceramic slurry B (solid phase containing 20% ​​ZrO2): Weigh 64 parts by weight of Al2O3 powder, 16 parts by weight of ZrO2 powder (particle size 0.5 μm), 20 parts by weight of photosensitive resin (trimethylolpropane triacrylate), 0.5 parts by weight of photoinitiator 819, and 1 part by weight of dispersant BYK9076. Add the weighed materials to a planetary ball mill and ball mill at 300 rpm for 240 min to obtain a uniform slurry with a viscosity of approximately 1350 mPa·s.

[0109] Photocurable ceramic slurry C (solid phase containing 40% ZrO2): Weigh 48 parts by weight of Al2O3 powder, 32 parts by weight of ZrO2 powder, 20 parts by weight of photosensitive resin (trimethylolpropane triacrylate), 0.5 parts by weight of photoinitiator 819, and 1 part by weight of dispersant BYK9076. Add the weighed materials to a planetary ball mill and ball mill at 300 rpm for 240 min to obtain a uniform slurry with a viscosity of approximately 1620 mPa·s.

[0110] Step 2): Inject UV-curable ceramic slurry A, UV-curable ceramic slurry B, and UV-curable ceramic slurry C into the three slurry tanks of the printer, respectively. Design a cuboid ceramic model (40mm × 10mm × 4mm). In the slicing software, set the gradient printing sequence: layers 1-5 use UV-curable ceramic slurry A, layers 6-12 use UV-curable ceramic slurry B, layers 13-21 use UV-curable ceramic slurry C, layers 22-28 use UV-curable ceramic slurry B, layers 29-33 use UV-curable ceramic slurry A, and so on, forming a non-uniform gradient transition layered structure. Set the printing parameters: laser power 300mW, scanning speed 6000mm / s, single layer thickness 50μm. During the printing process, the printer automatically switches the slurry tanks to complete the preparation of the ceramic green body.

[0111] Step 3) The ceramic blank is placed in a muffle furnace for degreasing treatment. The process parameters for degreasing treatment are: heating rate of 15℃ / h; degreasing treatment temperature of 600℃; and holding time at the degreasing treatment temperature of 3 hours.

[0112] Step 4): The degreased ceramic blank is placed in a high-temperature sintering furnace for sintering and then naturally cooled to room temperature to obtain an Al2O3-ZrO2 gradient layered ceramic material. The sintering process parameters are: heating rate of 10℃ / min; sintering temperature of 1650℃; and holding time at the sintering temperature of 3 hours.

[0113] Experimental Example 3

[0114] This experimental embodiment uses the multi-material photopolymerization printer described in the above embodiment to prepare an Al2O3-ZrO2 layered ceramic material with a relatively small gradient transition layer thickness. Specifically, it includes the following steps:

[0115] Step 1): Prepare three different light-curing ceramic slurries:

[0116] Photocurable ceramic slurry A (solid phase without ZrO2): Weigh 80 parts by weight of Al2O3 ceramic powder (particle size 0.5μm), 20 parts by weight of photosensitive resin (trimethylolpropane triacrylate), 0.5 parts by weight of photoinitiator 819, and 1 part by weight of dispersant BYK9076. Add the weighed materials to a planetary ball mill and ball mill at 300 rpm for 240 min to obtain a uniform slurry with a viscosity of approximately 1200 mPa·s.

[0117] Photocurable ceramic slurry B (solid phase containing 20% ​​ZrO2): Weigh 64 parts by weight of Al2O3 powder, 16 parts by weight of ZrO2 powder (particle size 0.5 μm), 20 parts by weight of photosensitive resin (trimethylolpropane triacrylate), 0.5 parts by weight of photoinitiator 819, and 1 part by weight of dispersant BYK9076. Add the weighed materials to a planetary ball mill and ball mill at 300 rpm for 240 min to obtain a uniform slurry with a viscosity of approximately 1350 mPa·s.

[0118] Photocurable ceramic slurry C (solid phase containing 40% ZrO2): Weigh 48 parts by weight of Al2O3 powder, 32 parts by weight of ZrO2 powder, 20 parts by weight of photosensitive resin (trimethylolpropane triacrylate), 0.5 parts by weight of photoinitiator 819, and 1 part by weight of dispersant BYK9076. Add the weighed materials to a planetary ball mill and ball mill at 300 rpm for 240 min to obtain a uniform slurry with a viscosity of approximately 1620 mPa·s.

[0119] Step 2): Inject UV-curable ceramic slurry A, UV-curable ceramic slurry B, and UV-curable ceramic slurry C into the three slurry tanks of the printer, respectively. Design a cuboid ceramic model (40mm × 10mm × 4mm). In the slicing software, set the gradient printing sequence: layers 1-2 use UV-curable ceramic slurry A, layers 3-4 use UV-curable ceramic slurry B, layers 5-6 use UV-curable ceramic slurry C, layers 7-8 use UV-curable ceramic slurry B, layers 9-10 use UV-curable ceramic slurry A, and so on, forming a symmetrical gradient structure. Set the printing parameters: laser power 300mW, scanning speed 6000mm / s, single layer thickness 50μm. During the printing process, the printer automatically switches the slurry tanks to complete the preparation of the ceramic green body.

[0120] Step 3): Place the ceramic blank in a muffle furnace for degreasing treatment. The process parameters for degreasing treatment are: heating rate of 15℃ / h; degreasing treatment temperature of 600℃; and holding time at the degreasing treatment temperature of 3 hours.

[0121] Step 4): After degreasing, the ceramic blank is placed in a high-temperature sintering furnace for sintering and then naturally cooled to room temperature to obtain an Al2O3-ZrO2 layered ceramic material with a relatively thin gradient transition layer. The sintering process parameters are as follows: heating rate of 10℃ / min; sintering temperature of 1650℃; and holding time at the sintering temperature of 3 hours.

[0122] Experimental Example 4

[0123] This experimental embodiment uses the photopolymerization 3D printer described in the above embodiment to prepare an Al2O3-ZrO2 layered ceramic material with a small gradient transition layer thickness. Specifically, it includes the following steps:

[0124] Step 1): Prepare three different light-curing ceramic slurries:

[0125] Photocurable ceramic slurry A (solid phase without ZrO2): Weigh 80 parts by weight of Al2O3 ceramic powder (particle size 0.5μm), 20 parts by weight of photosensitive resin (trimethylolpropane triacrylate), 0.5 parts by weight of photoinitiator 819, and 1 part by weight of dispersant BYK9076. Add the weighed materials to a planetary ball mill and ball mill at 300 rpm for 240 min to obtain a uniform slurry with a viscosity of approximately 1200 mPa·s.

[0126] Photocurable ceramic slurry B (solid phase containing 20% ​​ZrO2): Weigh 64 parts by weight of Al2O3 powder, 16 parts by weight of ZrO2 powder (particle size 0.5 μm), 20 parts by weight of photosensitive resin (trimethylolpropane triacrylate), 0.5 parts by weight of photoinitiator 819, and 1 part by weight of dispersant BYK9076. Add the weighed materials to a planetary ball mill and ball mill at 300 rpm for 240 min to obtain a uniform slurry with a viscosity of approximately 1350 mPa·s.

[0127] Photocurable ceramic slurry C (solid phase containing 40% ZrO2): Weigh 48 parts by weight of Al2O3 powder, 32 parts by weight of ZrO2 powder, 20 parts by weight of photosensitive resin (trimethylolpropane triacrylate), 0.5 parts by weight of photoinitiator 819, and 1 part by weight of dispersant BYK9076. Add the weighed materials to a planetary ball mill and ball mill at 300 rpm for 240 min to obtain a uniform slurry with a viscosity of approximately 1620 mPa·s.

[0128] Step 2): Inject UV-curable ceramic slurry A, UV-curable ceramic slurry B, and UV-curable ceramic slurry C into the three slurry tanks of the printer, respectively. Design a cuboid ceramic model (40mm × 10mm × 4mm). In the slicing software, set a gradient printing sequence: layers 1-15 use UV-curable ceramic slurry A, layers 16-30 use UV-curable ceramic slurry B, layers 31-45 use UV-curable ceramic slurry C, layers 46-60 use UV-curable ceramic slurry B, layers 61-75 use UV-curable ceramic slurry A, and so on, forming a symmetrical gradient structure. During the printing process, the printer automatically switches the slurry tanks to complete the preparation of the ceramic green body.

[0129] Step 3): Place the ceramic blank in a muffle furnace for degreasing treatment. The process parameters for degreasing treatment are: heating rate of 15℃ / h; degreasing treatment temperature of 600℃; and holding time at the degreasing treatment temperature of 3 hours.

[0130] Step 4): After degreasing, the ceramic blank is placed in a high-temperature sintering furnace for sintering and then naturally cooled to room temperature to obtain an Al2O3-ZrO2 layered ceramic material with a relatively thin gradient transition layer. The sintering process parameters are as follows: heating rate of 10℃ / min; sintering temperature of 1650℃; and holding time at the sintering temperature of 3 hours.

[0131] Comparative Example 1

[0132] Comparative Example 1 prepared pure Al2O3 ceramic material as a performance comparison benchmark.

[0133] A photopolymer 3D printer was used to print photopolymer ceramic slurry A, printing 80 layers to obtain a ceramic green body. The ceramic green body was then degreased and sintered to obtain the ceramic material. The degreasing and sintering processes were exactly the same as in Experimental Example 1.

[0134] The mechanical properties of the ceramic materials prepared in Experimental Examples 1-4 and Comparative Example 1 are shown in Table 1.

[0135] Table 1

[0136]

[0137] As can be seen from Table 1:

[0138] 1) Compared with Comparative Example 1, the Al2O3-ZrO2 gradient layered ceramic material prepared in Experimental Example 1 has higher flexural strength and fracture toughness.

[0139] 2) As can be seen from Experimental Examples 1, 3, and 4, the thickness of the gradient transition layer (i.e., the number of consecutive printing layers of the same slurry) has a significant impact on the performance of the samples. When the number of consecutive printing layers for each slurry decreases, the accumulated internal stress may induce microcracks. Therefore, the flexural strength and fracture toughness of Experimental Example 3 are lower than those of Experimental Example 1, which has a larger transition layer thickness. When the number of consecutive printing layers for each slurry is too large, the toughening effect of the gradient transition layered structure weakens. Therefore, the flexural strength and fracture toughness of Experimental Example 4 are also lower than those of Experimental Example 1.

[0140] In summary, the scheme of this experimental embodiment successfully prepared a new high-strength and high-toughness ceramic material. Based on the photopolymerization 3D printer and the preparation method of gradient layered ceramic materials provided in this embodiment, a material with both high flexural strength (≥300MPa) and high fracture toughness (≥5.0MPa·m) was successfully prepared. 1 / 2 Gradient layered ceramics exhibit performance far exceeding that of traditional abrupt interface ceramics, broadening the application prospects of high-performance ceramic materials in extreme environments.

[0141] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims

1. A multi-material photopolymerization printer, characterized in that, The multi-material photopolymer printer includes: Printing support stage; A material tank structure includes multiple material tank units; each material tank unit includes a slurry tank and a slurry curing area; the slurry tank is used to deliver slurry to the slurry curing area of ​​the same material tank unit; a release film is laid on the inner bottom of the slurry curing area; the material tank structure is movable on the printing support table to move the slurry curing area containing the required slurry to the printing area on the printing support table; A forming platform is located above the printing support stage. During the photopolymerization printing process, the platform descends into the slurry curing area located in the printing area and, under the irradiation of an ultraviolet light source system, the slurry between the forming platform and the release film is cured.

2. The multi-material photopolymer printer according to claim 1, characterized in that, The printing support platform is provided with a translation drive mechanism; wherein, the translation drive mechanism is connected to the material tank structure to drive the material tank structure to move on the printing support platform, thereby moving the slurry solidification area containing the required slurry to the printing area on the printing support platform; Preferably, the translation drive mechanism is a lead screw and slider structure; more preferably, the drive mechanism of the lead screw and slider structure is a linear module or a servo motor.

3. The multi-material photopolymer printer according to claim 2, characterized in that, A scraper is provided between the slurry tank and the slurry curing area in each of the slurry tank units; wherein, by controlling the movement of the scraper, the slurry in the slurry tank is transported to the slurry curing area, and the slurry in the slurry curing area is spread.

4. The multi-material photopolymer printer according to any one of claims 1-3, characterized in that, The trough structure includes: A frame structure having an open inner cavity at the top; At least one partition is installed within the frame structure to divide the inner cavity into multiple material trough units; preferably, if there are multiple partitions, the partitions are arranged parallel to each other; the material trough units are arranged parallel to each other. A linkage structure is slidably connected to both ends and partitions of the frame structure, used to divide each material tank unit into a slurry tank and a slurry curing area, and can slide along the slurry curing area; Preferably, a scraper is provided on the connecting rod structure at each material tank unit position, so that the scraper can be moved by controlling the movement of the connecting rod structure, so that the slurry in the slurry tank is transported to the slurry curing area and the slurry in the slurry curing area is spread. Preferably, the scraper is detachably connected to the connecting rod structure to facilitate cleaning, maintenance, and replacement of the scraper; preferably, the detachable nature facilitates the replacement of scrapers with different angles, enabling independent adjustment of the scraper angle; Preferably, the scraper is connected to the linkage structure via a height-adjustable mounting mechanism to facilitate adjustment of the vertical gap between the scraper blade and the release film.

5. The multi-material photopolymer printer according to claim 4, characterized in that, The frame structure includes: A first frame is connected to a translation drive mechanism on the printing support stage; The second frame is superimposed on the first frame; A glass plate is placed on the first frame to serve as the inner bottom of the slurry curing area, and the edge of the glass plate is fixed between the first frame and the second frame. A release film is laid on the glass plate, and the edge of the release film is fixed between the first frame and the second frame.

6. The multi-material photopolymer printer according to any one of claims 1-5, characterized in that, The forming platform is a pull-out forming platform; and / or A support structure is connected to the printing support platform; wherein a lifting structure is provided on the support structure; wherein the lifting structure can rise or fall along the support structure; the forming platform is connected to the lifting structure, so as to rise or fall relative to the printing area under the action of the lifting structure; and / or A light source system is provided in the inner cavity of the printing support stage, and the light source system is located directly below the printing area; and / or The number of the material trough units is 2-6; preferably, each material trough unit is an independent and detachable structure; and / or The photopolymer 3D printer includes a control system; wherein, the control system is used to control the translation drive mechanism to drive the material tank structure to move, so as to move the slurry curing area containing the required slurry to the printing area on the printing support platform; the control system is used to control the forming platform to descend into the slurry curing area located in the printing area, so that the slurry between the forming platform and the release film is cured under the irradiation of the ultraviolet light source system, and then control the forming platform to rise and separate the cured resin layer from the release film, and then descend again to cure and print the next layer, and so on until the model is completed.

7. A method for preparing a gradient layered ceramic material, characterized in that, Gradient layered ceramic materials are prepared using the multi-material photopolymerization printer described in any one of claims 1-6.

8. The method for preparing the gradient layered ceramic material according to claim 7, characterized in that, The preparation method of the gradient layered ceramic material includes the following steps: Slurry loading step: Different types of photocurable ceramic slurries are injected into the slurry tanks of different material tank units on the multi-material photocurable printer; Photopolymerization 3D printing steps: Set the printing sequence in the control system of the multi-material photopolymerization printer so as to switch the material tank unit located in the printing area during the photopolymerization printing process according to the printing sequence; Then, photopolymerization 3D printing is performed to obtain a ceramic blank with a compositional gradient; preferably, the thickness of a single printed layer is 20-200μm, and the number of consecutive printed layers of the same ceramic material is 3-10. Degreasing and sintering treatment: The ceramic blank is subjected to degreasing and sintering treatment to obtain a gradient layered structure ceramic material.

9. The method for preparing the gradient layered ceramic material according to claim 7, characterized in that, Different types of photocurable ceramic slurries differ in one or more of the following: ceramic powder type, ceramic particle size, ceramic fiber content, and reinforcing agent composition; and / or Each of the aforementioned photocurable ceramic slurries comprises ceramic powder, photosensitive resin, diluent, photoinitiator, and dispersant; more preferably, each of the aforementioned photocurable ceramic slurries further comprises ceramic fibers and / or reinforcing agents; and / or The degreasing treatment is carried out in a protective atmosphere, wherein the temperature of the degreasing treatment is 500-700℃ and the holding time is 120-360 min; and / or The sintering process is carried out in a protective atmosphere; wherein the sintering temperature is 1200-1700℃ and the holding time is 120-360min.

10. A gradient layered ceramic material, characterized in that, The gradient layered ceramic material is prepared by the method for preparing gradient layered ceramic material according to any one of claims 7-9; Preferably, the flexural strength of the gradient layered ceramic material is not less than 300 MPa, and the fracture toughness is not less than 5.0 MPa·m. 1 / 2 ; Preferably, the gradient layered ceramic material exhibits a gradient change in composition and properties in the thickness direction, without macroscopic cracks.

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