Support structure for ceramic green bodies and method for drying ceramic green bodies

Abstract

The application discloses a kind of support structure of ceramic green body and ceramic green body defatting drying method, it is related to ceramic processing technical field, wherein, the support structure of ceramic green body includes support component;The support component is used to be set in the outer periphery of ceramic green body, or it is used to be inserted in ceramic green body, to carry out circumferential constraint and radial support to the ceramic green body, the support component has hollow portion along the distribution of periphery side, the hollow portion is used to be permeated by defatting solvent, to carry out defatting to the ceramic green body;And / or, the hollow portion is used to be passed by airflow, to carry out drying to the ceramic green body;The technical scheme provided by the application makes ceramic green body in defatting and drying stage can keep its own form, avoid deformation, simultaneously avoid to ceramic green body shielding, lead to ceramic green body defatting, drying efficiency is low, product quality is worse.

Description

Technical Field

[0001] This invention relates to the field of ceramic processing technology, and in particular to a support structure for ceramic green bodies and a method for degreasing and drying ceramic green bodies. Background Technology

[0002] In the support fixtures used for processing thin-walled ceramic green bodies, existing ceramic / metal fixtures are mainly used for limiting and fixing during the high-temperature sintering stage. These ceramic / metal fixtures are solid or simple groove-shaped structures with extremely low perforation. If placed in a solvent degreasing tank, they will severely block solvent penetration, resulting in uneven degreasing and binder residue. If fixtures are not used to support the thin-walled ceramic green bodies, the ceramic green bodies are prone to elliptical deformation quality problems after degreasing / drying. Summary of the Invention

[0003] The main objective of this invention is to propose a support structure for ceramic green bodies and a method for degreasing and drying ceramic green bodies, aiming to enable ceramic green bodies to maintain their own shape during the degreasing and drying stages while avoiding problems such as uneven degreasing and binder residue. To achieve the above objectives, the present invention proposes a support structure for ceramic green bodies, comprising: A support assembly is provided for fitting around the outer periphery of a ceramic green body or for inserting into the ceramic green body to provide circumferential constraint and radial support for the ceramic green body. The support assembly has perforated portions distributed along the periphery for allowing degreasing solvent to penetrate and degrease the ceramic green body; and / or, the perforated portions allow airflow to pass through and dry the ceramic green body.

[0004] In one embodiment, the support assembly is removably inserted into the ceramic green body, the support assembly including a plurality of support members, the plurality of support members surrounding to form the support assembly, and the outer surface of each support member being adapted to a corresponding position on the inner wall surface of the ceramic green body; And / or, the material of the support component is any one or more of polylactic acid, acrylonitrile-butadiene-styrene copolymer, polypropylene, polyetheretherketone, and polyetherketoneketone.

[0005] In one embodiment, the support member includes a first support portion, a second support portion, and the hollow portion; The hollow portion is arranged circumferentially along the support assembly, and the hollow portion is used for degreasing solvent penetration and / or airflow passage. The first support portion is arranged radially along the support assembly in the hollow portion, and the first support portion is used for radial support of the ceramic green body. The second support portion is arranged circumferentially along the support assembly in the hollow portion, and the second support portion is used for circumferential constraint of the ceramic green body.

[0006] In one embodiment, the hollowing-out ratio of the hollowed-out portion is not less than 60%; And / or, the support assembly is used for clearance fitting with the inner wall of the ceramic green body.

[0007] In one embodiment, the first support portion has a first docking end disposed away from the hollow portion, and the first docking end of each first support portion abuts and engages with the first docking end of at least one other first support portion. And / or, the support assembly has an insertion end and an opening end disposed opposite to the insertion end, the support assembly being inserted into the ceramic green body from the insertion end, the second support portion being disposed at the opening end, and the hollow portion and the first support portion extending from the opening end to the insertion end.

[0008] This invention also proposes a method for degreasing and drying ceramic green bodies, which uses the support structure described above to support the ceramic green bodies, including the following steps: Support structure for making ceramic green bodies; The support structure is inserted inside the ceramic green body or fitted onto the outer periphery of the ceramic green body; Degreasing is performed on the ceramic green body used to assemble the support structure; The ceramic green body, after assembling the support structure and degreasing, is dried. Remove the support structure from the dried ceramic green body.

[0009] In one embodiment, the support structure for producing ceramic green bodies includes the following steps: Using polylactic acid, acrylonitrile-butadiene-styrene copolymer, polypropylene, polyetheretherketone, or polyetherketoneketone as the printing substrate, multiple support components of the support structure are printed using 3D printing technology.

[0010] In one embodiment, the step of inserting the support structure inside or around the ceramic green body includes: Insert multiple support components into the ceramic green body; Multiple support components are enclosed inside the ceramic green body to form a support structure, and a pre-set gap is formed between the support components and the inner wall of the ceramic green body.

[0011] In one embodiment, the step of degreasing the ceramic green body for assembling the support structure includes: The ceramic green body for assembling the support structure is placed in n-heptane degreasing solvent, soaked at a first preset temperature for a first preset time, then removed and soaked in kerosene for a second preset time. The ceramic green body for assembling the support structure is removed from the kerosene and air-dried.

[0012] In one embodiment, the step of drying the ceramic green body after assembling the support structure and degreasing includes: The degreased ceramic green body, along with the supporting structure, is transferred to a hot air circulation device and dried at a second preset temperature for a third preset time. The hot air circulation equipment is adjusted to the third preset temperature, and then the ceramic green body is dried for a fourth preset time. The third preset temperature is greater than the second preset temperature.

[0013] The technical solution of the present invention provides a support structure including a support component, which is used to fit around the outer periphery of the ceramic green body or to be inserted into the ceramic green body to provide circumferential constraint and radial support for the ceramic green body. A hollow part is reserved on the periphery of the support component to allow the degreasing solvent to penetrate and degrease the ceramic green body, and / or to allow airflow to pass through and dry the ceramic green body. This allows the ceramic green body to maintain its own shape during the degreasing and drying stages, avoids deformation, and avoids obstruction of the ceramic green body, which would lead to lower degreasing and drying efficiency and poorer product quality. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0015] Figure 1 This is a schematic diagram of the support structure for the ceramic green body and the assembly of the ceramic green body provided by the present invention. Figure 2 A schematic diagram of the support structure for the ceramic green body and the assembly process of the ceramic green body provided by the present invention; Figure 3 for Figure 2 A schematic diagram of the structure of one embodiment of the middle support member; Figure 4 A schematic diagram of an embodiment of the support structure for ceramic green bodies provided by the present invention; Figure 5 A schematic flowchart of the ceramic green body degreasing and drying method provided by the present invention; Figure 6 A comparative chart of experimental data for the degreasing and drying method of ceramic green bodies provided by the present invention.

[0016] Explanation of icon numbers: 100. Support structure; 10. Support component; 10a. Insertion end; 10b. Open end; 11. Supporting element; 111. First support part; 1111. First mating end; 112. Second support part; 113. Hollowed-out part; 200. Ceramic green body.

[0017] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0019] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0020] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0021] In the support fixtures used for processing thin-walled ceramic green bodies, existing ceramic / metal fixtures are mainly used for limiting and fixing during the high-temperature sintering stage. These ceramic / metal fixtures are solid or simple groove-shaped structures with extremely low perforation. If placed in a solvent degreasing tank, they will severely block solvent penetration, resulting in uneven degreasing and binder residue. If fixtures are not used to support the thin-walled ceramic green bodies, the ceramic green bodies are prone to elliptical deformation quality problems after degreasing / drying.

[0022] This invention proposes a support structure for ceramic green bodies. This structure allows the ceramic green body 200 to maintain its shape during the degreasing and drying stages, preventing deformation, and also avoiding obstruction of the ceramic green body 200, which could lead to reduced degreasing and drying efficiency and poorer product quality.

[0023] Please see Figures 1 to 4 In one embodiment of the present invention, the support structure of the ceramic green body includes a support component 10; the support component 10 is used to be sleeved on the outer periphery of the ceramic green body 200, or to be inserted into the ceramic green body 200, so as to provide circumferential constraint and radial support for the ceramic green body 200; the support component 10 has a hollow portion 113 distributed along the periphery; the hollow portion 113 is used to allow degreasing solvent to penetrate, so as to degrease the ceramic green body 200; and / or, the hollow portion 113 is used to allow airflow to pass through, so as to dry the ceramic green body 200.

[0024] In this invention, the support structure 100 of the ceramic green body 200 can be formed using 3D printing technology. During the degreasing and drying process of the ceramic green body 200, the support structure can be inserted into the outer periphery of the ceramic green body 200 or into the ceramic green body 200 to support the ceramic green body 200 and prevent softening, structural de-rounding, and elliptical distortion due to the dissolution of binder during solvent degreasing and drying.

[0025] The perforated portion 113 of the support component 10 can be distributed along the periphery of the support component 10. The perforated portion 113 has a plurality of spaced perforated holes. When the ceramic green body 200 is degreased by solvent replacement, the perforated holes allow the solvent to flow through and uniformly contact the outer or inner wall of the ceramic green body 200, dissolving the paraffin-based binder inside the ceramic green body 200. Alternatively, after the ceramic green body 200 is degreased, when it is dried by hot air circulation, the perforated holes allow airflow to pass through and uniformly blow on the outer or inner wall of the ceramic green body 200, drying the ceramic green body 200 by thermal convection.

[0026] The support structure 100 can be manufactured using 3D printing technology. The printing material can be any one of polylactic acid (PLA), acrylonitrile-butadiene-styrene copolymer (ABS), polypropylene (PP), polyetheretherketone (PEEK), or polyetherketoneketone (PEKK), and can be printed using an FDM filament printer (fused deposition modeling filament printer). It is understood that the ambient temperature of the ceramic green body 200 during the degreasing stage generally does not exceed 50 degrees Celsius. When the support structure 100 uses the aforementioned materials, it can meet the above temperature requirements, and the support structure 100 is less likely to deform and lose its supporting effect. Furthermore, when the ceramic green body undergoes solvent degreasing, hydrocarbon solvents are typically used. The aforementioned materials are less likely to react with hydrocarbon solvents, preventing the release of heavy metals that could contaminate the solvent and the ceramic green body 200.

[0027] It is understandable that during the debinding of the ceramic green body 200, the paraffin-based binder inside the ceramic green body 200 will continuously be lost, causing the ceramic green body 200 to lose the support of the binder and thus easily deform, especially for thin-walled ceramic green bodies 200. After debinding, deformation is also likely to occur during the subsequent drying stage.

[0028] The existing support fixtures used in the high-temperature sintering stage of ceramic green bodies typically have a very low perforation rate. If used in the degreasing stage, they will severely block solvent penetration, resulting in uneven degreasing and low drying efficiency of the subsequent ceramic green bodies.

[0029] Therefore, this invention designs a support structure 100 for use in the degreasing and drying stages of ceramic green bodies 200. The support component 10 is fitted around the outer periphery of the ceramic green body 200 or inserted inside the ceramic green body 200, providing radial support and circumferential constraint. Furthermore, a perforated portion 113 is reserved on the periphery of the support component 10 to increase its perforation rate. During the degreasing and drying stages of the ceramic green body 200, this design prevents softening and deformation while avoiding situations where the support structure 100 obstructs the penetration of the degreasing solvent and the passage of the drying airflow, thus preventing reduced degreasing and drying efficiency and poor performance.

[0030] The technical solution of the present invention provides a support structure 100 including a support component 10, which is used to fit around the outer periphery of the ceramic green body 200 or to be inserted into the ceramic green body 200, thereby constraining the ceramic green body 200 circumferentially and providing radial support. A hollow portion 113 is reserved on the periphery of the support component 10 to allow the degreasing solvent to penetrate and degrease the ceramic green body 200, and / or to allow airflow to pass through and dry the ceramic green body 200. This allows the ceramic green body 200 to maintain its own shape during the degreasing and drying stages, avoiding deformation, and at the same time avoiding obstruction of the ceramic green body 200, which would lead to lower degreasing and drying efficiency and poorer product quality.

[0031] like Figure 2 As shown, optionally, the support assembly 10 is removably inserted into the ceramic green body 200. The support assembly 10 includes a plurality of support members 11, which are arranged to form the support assembly 10. The outer surface of each support member 11 is adapted to a corresponding position on the inner wall surface of the ceramic green body 200.

[0032] It is understandable that after degreasing, the ceramic green body 200 loses internal material, its porosity increases, and it usually shrinks to some extent. Therefore, when the support component 10 is inserted into the ceramic green body 200 to support it, a supporting force can be formed on the inner wall of the ceramic green body 200 when it shrinks, thereby preventing the ceramic green body 200 from deforming.

[0033] Meanwhile, the ceramic green body 200 generally has an opening, and the support assembly 10 can be inserted into the ceramic green body 200 through the opening. The inner diameter of the ceramic green body 200 can be the same or different along the axial direction. When the inner diameter of the ceramic green body 200 gradually increases inward from its opening, the diameter of the internal cross-section of the ceramic green body 200 is larger than the diameter at the opening. In this case, it is difficult for the integrally set support assembly 10 to be inserted into the ceramic green body 200 through the opening to support the inner wall of the ceramic green body 200. Therefore, the present invention sets the support assembly 10 as multiple support members 11. Multiple support members 11 can be sequentially inserted into the ceramic green body 200 through the opening to form a complete support assembly 10 inside the ceramic green body 200 to support the ceramic green body 200. The outer surface of each support member 11 can be adapted to the corresponding position of the inner wall surface of the ceramic green body 200, that is, to support the corresponding area of ​​the ceramic green body 200.

[0034] In this way, the support structure 100 can be adapted to ceramic green bodies 200 of different shapes, and the protection of various ceramic green bodies 200 during the degreasing and drying stages can be met.

[0035] The number of support members 11 can be set to two, three, four, five, etc., without any restriction. It is only necessary to ensure that all support members 11 can be enclosed to form a cylindrical shape to support the inner wall of the ceramic green body 200.

[0036] Optionally, the material of the support component 10 is any one or more of polylactic acid, acrylonitrile-butadiene-styrene copolymer, polypropylene, polyetheretherketone, and polyetherketoneketone.

[0037] It is understandable that the ambient temperature of the ceramic green body 200 during the degreasing stage is generally no higher than 50 degrees Celsius. When the support structure 100 uses the aforementioned material, the temperature requirement can be met, and the support structure 100 is less likely to deform and lose its supporting effect. At the same time, when the ceramic green body undergoes solvent degreasing, hydrocarbon solvents are usually used, and the aforementioned material is less likely to react with hydrocarbon solvents.

[0038] The support component 10 can be printed using an FDM filament printer, with polylactic acid (PLA) preferred as the printing material. PLA has a relatively low cost and can be quickly printed using a regular FDM filament printer without the need for mold making, which can reduce the overall manufacturing cost of the support component 10 and shorten the manufacturing cycle.

[0039] like Figure 3 As shown, optionally, the support member 11 includes a first support portion 111, a second support portion 112, and the hollow portion 113; The hollow portion 113 is arranged circumferentially along the support component 10. The hollow portion 113 is used for the penetration of degreasing solvent and / or the passage of airflow. The first support portion 111 is arranged radially along the support component 10 in the hollow portion 113. The first support portion 111 is used to provide radial support for the ceramic green body 200. The second support portion 112 is arranged circumferentially along the support component 10 in the hollow portion 113. The second support portion 112 is used to provide circumferential constraint for the ceramic green body 200.

[0040] The hollow portion 113 serves as the base of the support member 11, and its overall hollow design allows for solvent penetration and airflow. The first support portion 111 is located inside the hollow portion 113 and extends radially along the support assembly 10. The first support portion 111 can abut against the hollow portions 113 of other support members 11, or the first support portion 111 can abut against the first support portions 111 of other support members 11, to provide radial support and prevent the ceramic green body 200 from elliptical deformation. The second support portion 112 can be arc-shaped and extends circumferentially along the support assembly 10. The second support portions 112 of all support members 11 can be sequentially connected to form a ring, providing circumferential constraint on the ceramic green body 200 and preventing overall shrinkage deformation of the ceramic.

[0041] Meanwhile, the first support part 111 and the second support part 112 cooperate with each other to provide radial support and circumferential constraint at the same time to prevent the ceramic green body 200 from becoming elliptical and shrinking inward.

[0042] The perforation rate of the first support portion 111 and the second support portion 112 is less than that of the perforation rate of the perforation portion 113. Alternatively, the first support portion 111 and the second support portion 112 may be entirely solid structures without reserving space for the perforation portion 113, thus ensuring effective support for the ceramic green body 200.

[0043] Optionally, the hollowing-out portion 113 has a hollowing-out ratio of not less than 60%; It is understandable that the perforation rate can be calculated as the ratio of the sum of the opening areas of all the perforated holes in the perforated part 113 to the outer wall area of ​​the perforated part 113. When the perforation rate reaches 60%, it ensures that the perforated part 113 has sufficient openings to connect the inner cavity of the support structure 100 with the outer surface of the ceramic green body 200. This ensures that sufficient solvent can penetrate through the support assembly 10 into the ceramic green body 200 for degreasing. Simultaneously, during the drying stage, it ensures the air convection intensity on the inner wall surface of the ceramic green body 200, ensuring the drying efficiency of the ceramic green body 200.

[0044] Optionally, the support component 10 is used to fit with the inner wall of the ceramic green body 200 with a clearance.

[0045] It is understandable that if the support component 10 is directly attached to the inner wall surface of the ceramic green body 200, although the perforated portion 113 allows solvent to pass through, the solid structure of the perforated portion 113 attached to the inner wall surface of the ceramic green body 200 will cause this area to lose solution flow. The solvent flowing from the perforated hole to the ceramic green body 200 can only flow through the internal pores of the ceramic green body 200 to the corresponding area of ​​the solid structure of the support component 10 attached to the inner wall surface, affecting the degreasing efficiency of the ceramic green body 200. The same applies to the drying operation of the ceramic green body 200.

[0046] To achieve this, the present invention provides a clearance fit between the support component 10 and the inner wall surface of the ceramic green body 200. After the support component 10 is inserted into the ceramic green body 200, a certain gap is maintained between the ceramic green body 200 and the support component 10, ensuring that the solvent can flow in the gap between them, thereby ensuring the degreasing efficiency of the ceramic green body 200.

[0047] For example, after the support component 10 is assembled inside the ceramic green body 200, the gap between the support component 10 and the ceramic green body 200 can be 0.3 mm to 0.5 mm.

[0048] like Figure 2As shown, optionally, the first support portion 111 has a first docking end 1111 disposed away from the hollow portion 113, and the first docking end 1111 of each first support portion 111 abuts and engages with the first docking end 1111 of at least one other first support portion 111.

[0049] When the number of support members 11 is not less than three, the first docking end 1111 can be provided with two docking surfaces arranged at an angle. Each docking surface is connected to the corresponding docking surface of the adjacent support member 11, so that the first support part 111 can dock with at least two adjacent first support parts 111, so that the support assembly 10 can form a more stable radial support through the first support part 111, and can provide a uniform and stable radial support force for the ceramic green body 200.

[0050] When there are two support members 11, the first mating ends 1111 of the two first support parts 111 can abut against each other.

[0051] Alternatively, in another embodiment, the first mating end 1111 can be engaged with the first mating end 1111 of at least one other first support portion 111. Through engagement, a stable connection can be formed between the multiple first support portions 111, allowing the multiple support members 11 to be rigidly connected within the ceramic green body, forming a single support assembly 10 that supports the ceramic green body within the ceramic green body.

[0052] like Figure 3 , Figure 4 As shown, in one embodiment, the support component 10 has an insertion end 10a and an opening end 10b disposed opposite to the insertion end 10a. The support component 10 is used to be inserted into the ceramic green body 200 from the insertion end 10a. The second support portion 112 is disposed at the opening end 10b. The hollow portion 113 and the first support portion 111 extend from the opening end 10b to the insertion end 10a.

[0053] It is understandable that when the second support 112 is located at the open end 10b, the second support 112 can be set relatively far away from the ceramic green body 200, reducing the relative area between the non-hollowed-out position of the support 11 and the ceramic green body 200, thus avoiding affecting the passage of solvent and the degreasing operation of the ceramic green body 200.

[0054] When the first support extends from the opening end 10b to the insertion end 10a, the multiple first support parts 111 can not only cooperate with each other to provide radial support for the ceramic green body 200, but also cooperate with each other to provide axial support for the ceramic green body 200. Combined with the annular support of the second support part 112, the structural strength of each area of ​​the support assembly 10 is better, and the anti-deformation support effect of the ceramic green body 200 during the degreasing and drying process is better.

[0055] When the hollow portion 113 extends from the opening end 10b to the insertion end 10a, the arrangement of the hollow portion 113 along the circumferential direction allows the hollow portions 113 of each support member 11 to cooperate with each other and be distributed to various areas of the inner wall surface of the ceramic green body 200, ensuring that the first support portion 111 and the second support portion 112 can play the role of circumferential constraint and radial support through the hollow portion 113.

[0056] This invention also proposes a method for degreasing and drying a ceramic green body 200. The ceramic green body 200 is supported by a support structure 100 as described above. The specific structure of the support structure 100 is as described in the above embodiments. Since this method for degreasing and drying a ceramic green body 200 adopts all the technical solutions of all the above embodiments, it possesses at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be elaborated further here. The method for degreasing and drying a ceramic green body 200 includes the following steps: S100: Support structure 100 for making ceramic green body 200; Among them, the support structure 100 of the ceramic green body 200 can be printed using 3D printing technology. Specifically, each support component 11 can be printed in stages. After printing, all the support components 11 can be spliced ​​together to form the support structure 100.

[0057] Optionally, the support structure 100 for manufacturing the ceramic green body 200 includes the following steps: Using polylactic acid, acrylonitrile-butadiene-styrene copolymer, polypropylene, polyetheretherketone, or polyetherketoneketone as the printing substrate, multiple support components 11 of the support structure 100 are printed using 3D printing technology.

[0058] For example, when printing the support structure 100, FDM technology can be used for 3D printing, and polylactic acid filament is preferably used as the printing material. The support structure 100 formed by the printed support members 11 can be a hollow cage-like structure, formed by at least two support members 11.

[0059] During printing, the printhead temperature can be 230 degrees Celsius, the heated bed temperature can be 100 degrees Celsius, the printing speed can be 30 mm / s, and the printed layer thickness can be 0.2 mm. At the locations of the first support member 11 and the second support member 11, the material filling rate during printing can be 100%, while the filling rate of the corresponding hollow portion 113 is lower, ensuring that the hollow portion 113 has a hollow rate of not less than 60%.

[0060] S200: Insert the support structure 100 inside the ceramic green body 200 or fit it around the ceramic green body 200; Specifically, the support structure 100 can be inserted inside the ceramic green body 200. Optionally, the step of inserting the support structure 100 inside or around the ceramic green body 200 includes: Multiple support members 11 are inserted into the ceramic green body 200 respectively; Multiple support members 11 enclose the ceramic green body 200 to form a support structure 100, and form a preset gap with the inner wall of the ceramic green body 200.

[0061] The support structure 100 can be inserted inside the ceramic green body 200 before degreasing, during the degreasing process, or during the drying process. No limitation is made here.

[0062] During assembly, multiple support members 11 can be inserted into the ceramic green body 200 in sequence. The positions of each support member 11 are adjusted inside the ceramic green body 200 so that the multiple support members 11 are connected in sequence to form a support structure 100 to support the ceramic green body 200.

[0063] After the support structure 100 is formed, a certain gap can be left between the support structure 100 and the inner wall surface of the ceramic green body 200, so that the solvent flowing from the hollow part 113 to the ceramic green body 200 can flow through the gap to the position opposite to the solid structure of the hollow part 113 on the inner wall surface of the ceramic green body 200, so that the ceramic green body 200 can be degreased evenly.

[0064] S300: Degrease the ceramic green body 200 of the assembly support structure 100; When degreasing the ceramic green body 200 of the assembly support structure 100, it can be carried out through at least two degreasing steps. Optionally, the degreasing steps of the ceramic green body 200 of the assembly support structure 100 include: The ceramic green body 200 of the assembly support structure 100 is placed in n-heptane degreasing solvent, soaked at a first preset temperature for a first preset time, then taken out and soaked in kerosene for a second preset time. The ceramic green body 200 of the assembly support structure 100 is removed from the kerosene and air-dried.

[0065] Specifically, the ceramic green body 200 has two degreasing stages and one air-drying stage during degreasing.

[0066] In the first degreasing stage, the ceramic green body 200 equipped with the support structure 100 can be vertically placed in a heptane degreasing tank, such that the heptane solvent level covers the entire ceramic green body 200, for example, the liquid level is 80 mm or more above the ceramic green body. The heptane solvent can be maintained at a first preset temperature, and the ceramic green body 200 is immersed in the solution for a first preset time.

[0067] The first preset temperature can be between 30 degrees Celsius and 50 degrees Celsius; here, the first preset temperature is selected as 50 degrees Celsius. The first preset duration can be between 12 hours and 48 hours; here, the first preset duration is selected as 24 hours.

[0068] During the degreasing process, n-heptane permeates through the gaps on the outer surface of the ceramic green body 200 and through the hollowed-out portion 113 of the support structure 100, uniformly contacting the outer and inner walls of the ceramic green body 200, dissolving the paraffin-based binder. The support structure 100 supports the ceramic green body 200. After soaking for the first preset time, the appearance of the ceramic green body 200 remains unchanged, with no swelling or cracking. The support structure 100 prevents softening, deformation, and loss of roundness.

[0069] It is understandable that n-heptane is a non-polar organic solvent with excellent solubility for low molecular weight binders such as paraffin and vegetable oil. Through the principle of "like dissolves like," n-heptane can quickly penetrate into the ceramic body, dissolving and extracting the low molecular weight binder components, thus removing most of the soluble binder in a short time.

[0070] In the second degreasing stage, the ceramic green body 200 is transferred to kerosene and soaked for a second preset time. Then, the ceramic green body 200, along with the supporting structure 100, is removed and allowed to air dry naturally until no kerosene remains on the surface. The second preset time can be 15 to 30 minutes.

[0071] It is understandable that after degreasing by soaking in n-heptane, a large number of capillary pores are formed inside the ceramic body. The n-heptane remaining in the pores evaporates at an extremely rapid rate in the air. If directly exposed, the rapid expansion of the gas phase can easily break open the capillary walls, leading to cracking of the model. Kerosene, on the other hand, has a much lower evaporation rate than n-heptane. During soaking, it can partially replace the residual n-heptane in the pores, thereby slowing down the subsequent evaporation rate, effectively protecting the pore structure and preventing cracking of the ceramic body. Therefore, ceramic bodies must be immediately soaked in kerosene after degreasing by soaking in n-heptane.

[0072] S400: Dry the ceramic green body 200 after assembling and degreasing the support structure 100; The drying of the ceramic green body 200 can be performed in two steps. Optionally, the step of drying the ceramic green body 200 after assembling the support structure 100 and degreasing it includes: The degreased ceramic green body 200, together with the support structure 100, is transferred to a hot air circulation device and dried at a second preset temperature for a third preset time. The hot air circulation equipment is adjusted to the third preset temperature, and then the ceramic green body 200 is dried for a fourth preset time. The third preset temperature is greater than the second preset temperature.

[0073] Among them, the hot air circulation equipment can be a hot air circulation box. It is understood that after degreasing, solvents such as n-heptane and kerosene still remain inside the ceramic green body 200. If the ceramic green body 200 is directly placed at a high preset temperature for drying, the residual solvent inside the ceramic green body 200 will vaporize and expand, resulting in increased internal stress in the ceramic green body 200, which can easily lead to bulging and cracking.

[0074] Therefore, in the drying process after degreasing the ceramic green body 200, the present invention first places the ceramic green body 200 at a lower third preset temperature for preliminary drying, so that the solvent remaining in the pores of the ceramic green body 200 slowly and evenly evaporates, removing most of the surface and shallow layer solvent. Then, it is placed at a higher fourth preset temperature, and the solvent remaining in the deep interior is completely evaporated by raising the temperature, ensuring complete drying.

[0075] The third preset temperature can be 40 to 50 degrees Celsius, preferably 50 degrees Celsius; the fourth preset temperature can be 70 to 90 degrees Celsius, preferably 80 degrees Celsius. The third preset duration can be 1 to 2 hours, preferably 1 hour; the fourth preset duration can be 5 to 7 hours, preferably 6 hours.

[0076] S500: Remove the support structure 100 from the dried ceramic green body 200.

[0077] It is understandable that, since the support structure 100 is composed of multiple support components 11 assembled within the ceramic green body 200, after the ceramic green body 200 has finished drying, the support structure 100 can be disassembled within the ceramic green body 200, restoring it to multiple unassembled support components 11, thus eliminating any potential limiting relationship between the ceramic green body 200 and the support structure 100. Then, the multiple support components 11 can be removed and used to support the next batch of ceramic green bodies 200 of the same specifications during degreasing and drying.

[0078] like Figure 6 As shown, the support structure 100 of the present invention was assembled on the ceramic green body 200 for experimental testing.

[0079] In Example 1, the ceramic green body 200 is made of alumina, is hemispherical in shape, and has a wall thickness of 1.5 mm. The corresponding support structure 100 is cage-like, made of PLA (polylactic acid), and uses multiple support members 11 arranged in segments to support the ceramic green body 200 inside. A solvent penetration gap of 0.3 mm is maintained between the support structure 100 and the ceramic green body 200, and the support is maintained throughout the process before and after degreasing. The solvents used for degreasing the ceramic green body 200 are n-heptane and kerosene, respectively. The degreasing temperature is 50 degrees Celsius, and the degreasing time is 24 hours. The subsequent drying temperature is maintained at 50 to 80 degrees Celsius, and the drying time is 6 hours. Experimental results show that after degreasing and drying, the axial deviation of the ceramic green body 200 supported by the above-mentioned support structure 100 is less than 0.2 mm, the surface is free of indentations and scratches, and the support structure 100 can be cleaned and reused.

[0080] In Example 2, unlike Example 1, the ceramic green body 200 is made of reaction-sintered silicon carbide, is cylindrical in shape, and has a wall thickness of 2 mm. The corresponding support structure 100 is also cylindrical. The drying time is 8 hours, and all other conditions are the same. Experimental results show that after degreasing and drying, the axial deviation of the ceramic green body 200 supported by the above-mentioned support structure 100 is less than 0.2 mm, the surface is free of indentations and scratches, and the support structure 100 can be cleaned and reused.

[0081] In Comparative Example 1, unlike Example 1, the ceramic green body 200 was not assembled with the support structure 100 during degreasing and drying, the shape of the ceramic green body 200 was not limited, and the other conditions were the same. The final ceramic green body 200 showed an axial deviation of 1.5 mm and became an elliptical shape.

[0082] The results show that using the support structure 100 of the present invention can significantly reduce the axial deviation of the ceramic green body 200 after degreasing and drying, resulting in better surface quality of the ceramic green body 200 without indentations or scratches. The support structure 100 is washable and reusable.

[0083] The above description is merely an exemplary embodiment of the present invention and does not limit the scope of protection of the present invention. Any equivalent structural transformations made based on the technical concept of the present invention and the contents of the specification and drawings of the present invention, or direct / indirect applications in other related technical fields, are included within the scope of protection of the present invention.

Claims

1. A support structure for a ceramic green body, characterized in that, include: A support assembly is provided for fitting around the outer periphery of a ceramic green body or for inserting into the ceramic green body to provide circumferential constraint and radial support for the ceramic green body. The support assembly has perforated portions distributed along the periphery for allowing degreasing solvent to penetrate and degrease the ceramic green body; and / or, the perforated portions allow airflow to pass through and dry the ceramic green body.

2. The support structure as described in claim 1, characterized in that, The support assembly is designed to be removably inserted into the ceramic green body. The support assembly includes multiple support members that are arranged together to form the support assembly. The outer surface of each support member is adapted to a corresponding position on the inner wall surface of the ceramic green body. And / or, the material of the support component is any one or more of polylactic acid, acrylonitrile-butadiene-styrene copolymer, polypropylene, polyetheretherketone, and polyetherketoneketone.

3. The support structure as described in claim 2, characterized in that, The support member includes a first support portion, a second support portion, and the hollow portion; The hollow portion is arranged circumferentially along the support assembly, and the hollow portion is used for degreasing solvent penetration and / or airflow passage. The first support portion is arranged radially along the support assembly in the hollow portion, and the first support portion is used for radial support of the ceramic green body. The second support portion is arranged circumferentially along the support assembly in the hollow portion, and the second support portion is used for circumferential constraint of the ceramic green body.

4. The support structure as described in claim 3, characterized in that, The hollowing ratio of the hollowed-out portion is not less than 60%; And / or, the support assembly is used for clearance fitting with the inner wall of the ceramic green body.

5. The support structure as described in claim 3, characterized in that, The first support portion has a first docking end disposed away from the hollow portion, and the first docking end of each first support portion abuts and engages with the first docking end of at least one other first support portion. And / or, the support assembly has an insertion end and an opening end disposed opposite to the insertion end, the support assembly being inserted into the ceramic green body from the insertion end, the second support portion being disposed at the opening end, and the hollow portion and the first support portion extending from the opening end to the insertion end.

6. A method for degreasing and drying ceramic green bodies, wherein the ceramic green bodies are supported by a support structure as described in any one of claims 1 to 5, characterized in that, Including the following steps: Support structure for making ceramic green bodies; The support structure is inserted inside the ceramic green body or fitted onto the outer periphery of the ceramic green body; Degreasing is performed on the ceramic green body used to assemble the support structure; The ceramic green body, after assembling the support structure and degreasing, is dried. Remove the support structure from the dried ceramic green body.

7. The method for degreasing and drying ceramic green bodies as described in claim 6, characterized in that, The supporting structure for making ceramic green bodies includes the following steps: Using polylactic acid, acrylonitrile-butadiene-styrene copolymer, polypropylene, polyetheretherketone, or polyetherketoneketone as the printing substrate, multiple support components of the support structure are printed using 3D printing technology.

8. The method for degreasing and drying ceramic green bodies as described in claim 6, characterized in that, The step of inserting the support structure inside or around the ceramic green body includes: Insert multiple support components into the ceramic green body; Multiple support components are enclosed inside the ceramic green body to form a support structure, and a pre-set gap is formed between the support components and the inner wall of the ceramic green body.

9. The method for degreasing and drying ceramic green bodies as described in claim 6, characterized in that, The step of degreasing the ceramic green body for assembling the support structure includes: The ceramic green body for assembling the support structure is placed in n-heptane degreasing solvent, soaked at a first preset temperature for a first preset time, then removed and soaked in kerosene for a second preset time. The ceramic green body for assembling the support structure is removed from the kerosene and air-dried.

10. The method for degreasing and drying ceramic green bodies as described in claim 6, characterized in that, The step of drying the ceramic green body after assembling the support structure and degreasing includes: The degreased ceramic green body, along with the supporting structure, is transferred to a hot air circulation device and dried at a second preset temperature for a third preset time. The hot air circulation equipment is adjusted to the third preset temperature, and then the ceramic green body is dried for a fourth preset time. The third preset temperature is greater than the second preset temperature.

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