Photocuring 3D printing zirconium carbide-based ultrahigh-temperature ceramic slurry as well as preparation method and application thereof

Abstract

Zirconium oxide is used as a zirconium source, organic matter powder with high char yield is used as a carbon source, and mixed powder of the zirconium oxide and the organic matter powder is used as a precursor of zirconium carbide ceramic, so that the photocuring 3D printing slurry is prepared. The curing depth of the photo-curing 3D printing zirconium carbide-based ultra-high-temperature ceramic slurry can be remarkably improved, and a zirconium carbide-based ultra-high-temperature ceramic precursor blank can be quickly printed. Furthermore, by combining with reasonable selection of the sintering temperature, the preparation of the zirconium carbide-based ultra-high-temperature ceramic component can be realized.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of ceramic additive manufacturing, and particularly relates to a photocurable 3D printing zirconium carbide-based ultra-high-temperature ceramic slurry as well as a preparation method and application thereof. BACKGROUND

[0002] Ultra-high-temperature ceramics (UHTC) are a class of advanced ceramic materials that can maintain their physical and chemical stability under extremely harsh conditions (temperature ≥ 2000℃ and accompanied by active atmosphere). The main components are carbides, borides and nitrides of refractory metals. Among numerous high-temperature structural materials, zirconium carbide (ZrC) based ultra-high-temperature ceramics exhibit a series of outstanding properties. It has a very high melting point, excellent high-temperature oxidation resistance, excellent ablation resistance, high mechanical strength and good thermal shock resistance. These properties enable it to effectively cope with extreme thermal and chemical environments generated by hypersonic long-time flight, atmospheric flight and re-entry into the atmosphere. Therefore, zirconium carbide-based ceramics are ideal candidate materials for manufacturing key components that withstand extreme thermal tests, typical applications include the nose cone of ballistic missiles, the leading edge structure of hypersonic vehicles, high-temperature resistant components of rocket engines and thermal protection systems of aircraft re-entering the atmosphere. At present, the mainstream manufacturing process of this kind of material is traditional sintering technology, such as hot-pressing sintering (HP), pressureless sintering (PLS) and spark plasma sintering (SPS). However, these methods are severely restricted by the geometry of the mold or sintering chamber, making it difficult to prepare complex structures.

[0003] In recent years, the rise of photocurable additive manufacturing technology (such as stereolithography SLA, digital light processing DLP) provides an effective way to overcome this limitation. This technology can directly form highly complex and fine ceramic green bodies by layer-by-layer solidification of photocurable resin slurry containing ceramic powder, and then obtain the final part after debinding and sintering, significantly improving the manufacturing flexibility and feasibility of complex shape ultra-high-temperature ceramic structures. Due to the high light absorption rate of zirconium carbide-based ultra-high-temperature ceramic powder in the ultraviolet-visible light band, the solidification depth of the photocurable slurry is low, making it difficult to form complex components by photocurable 3D printing technology. The present patent proposes a method for preparing zirconium carbide-based ultra-high-temperature ceramics by photocurable 3D printing. Using zirconia as the zirconium source and high-carbon organic powder as the carbon source, the mixed powder of the two powders is used as the precursor powder of zirconium carbide ceramics to prepare the photocurable slurry, which can significantly improve the solidification depth of the photocurable slurry and realize the rapid photocurable forming of zirconium carbide-based ultra-high-temperature ceramic components. SUMMARY

[0004] This section is intended to introduce some aspects of one or more embodiments of the present application, which are described below. This section is not intended to limit the scope or the patentability of the embodiments.

[0005] In view of the above and / or other problems existing in the prior art, the present application is proposed.

[0006] Therefore, the purpose of the present application is to overcome the deficiencies in the prior art, and provide a photocuring 3D printing zirconium carbide-based ultra-high temperature ceramic slurry, a preparation method and application thereof.

[0007] To solve the above technical problems, the present application provides the following technical scheme: a photocuring 3D printing zirconium carbide-based ultra-high temperature ceramic slurry, comprising,

[0008] Zirconia powder, polyacrylonitrile powder, photosensitive resin active diluent, dispersant, and photoinitiator.

[0009] The zirconia powder and the polyacrylonitrile powder account for 30-65% of the total mass of the slurry; the photosensitive resin mixed solution formed by mixing the photosensitive resin active diluent and the photoinitiator accounts for 30-65% of the total mass of the slurry; and the dispersant accounts for 1-5% of the total mass of the slurry.

[0010] The particle size of the zirconia powder is 0.05-10 microns, and the particle size of the polyacrylonitrile powder is 0.1-80 microns.

[0011] The purpose of the present application is to overcome the deficiencies in the prior art, and provide a preparation method of a photocuring 3D printing zirconium carbide-based ultra-high temperature ceramic slurry.

[0012] As a preferred scheme of the preparation method of the present application, wherein:

[0013] The zirconia and the polyacrylonitrile powder are weighed, the two powders are mixed by wet ball milling, and then the mixed powder is obtained by drying, grinding, and sieving;

[0014] The photosensitive resin active diluent and the photoinitiator are mixed to obtain a photosensitive resin mixed solution.

[0015] The mixed powder, the photosensitive resin mixed solution, and the dispersant are mixed to form a zirconium carbide-based ultra-high temperature ceramic slurry.

[0016] As a preferred scheme of the photocuring 3D printing zirconium carbide-based ultra-high temperature ceramic slurry of the present application, wherein: the zirconia and the polyacrylonitrile powder are weighed, and the mass ratio of the zirconia to the polyacrylonitrile powder is 1g of zirconia: 0.5-1g of polyacrylonitrile.

[0017] As a preferred scheme of the photocuring 3D printing zirconium carbide-based ultra-high temperature ceramic slurry, the two powders are mixed by wet ball milling, the material of the ball milling tank is polytetrafluoroethylene or nylon, the ball milling medium is ethanol, the material of the ball milling beads is zirconium oxide, the diameter of the ball milling beads is 3-10 mm, the rotating speed during ball milling is 150-500 rpm, the ball milling time is 2-24 h, the mass ratio of the mixed powders to the ball milling beads is 1 g of mixed powders: 1-10 g of ball milling beads, and the total mass of the mixed powders to the volume of ethanol is 1 g of mixed powders: 1-5 mL of ethanol.

[0018] As a preferred scheme of the photocuring 3D printing zirconium carbide-based ultra-high temperature ceramic slurry, the mixed powders are obtained by drying, grinding and sieving, the drying temperature is 80-90 DEG C, the drying time is 24-48 h, and the mesh number of the sieve is 100-150 meshes.

[0019] As a preferred scheme of the photocuring 3D printing zirconium carbide-based ultra-high temperature ceramic slurry, the photosensitive resin active diluent and the photoinitiator are mixed to obtain a photosensitive resin mixed solution, the photosensitive resin active diluent is trifunctional photosensitive resin monomer trimethylolpropane triacrylate, the photoinitiator is bis (2, 4, 6-trimethylbenzoyl) diphenyl phosphine oxide, and the mass ratio of the photosensitive resin active diluent to the photoinitiator is 100 g: 1-5 g.

[0020] The application aims to overcome the defects in the prior art and provide the application of the zirconium carbide-based ultra-high temperature ceramic slurry in photocuring 3D printing zirconium carbide-based ultra-high temperature ceramics.

[0021] As a preferred scheme of the application, the zirconium carbide-based ultra-high temperature ceramic slurry is printed by a photocuring 3D printer to form a zirconium carbide-based ultra-high temperature ceramic precursor blank, the printed blank is sequentially cleaned, degreased and high-temperature sintered to obtain the zirconium carbide-based ultra-high temperature ceramic.

[0022] The degreasing is that the printed sample is placed in an alumina crucible and embedded in zirconia ceramic powder, the crucible is placed in a tube furnace, the temperature is raised from room temperature to 600 DEG C at a temperature rising rate of 0.05-5 DEG C / min under an argon atmosphere, and the temperature is kept at 100 DEG C, 300 DEG C, 400 DEG C and 600 DEG C for 1-2 h respectively, and then cooled to room temperature.

[0023] As a preferred scheme of the application, the high-temperature sintering is pressureless sintering or gas pressure sintering, and the sintering temperature is not lower than 1600 DEG C.

[0024] The application has the following beneficial effects:

[0025] The present application uses zirconium oxide as a zirconium source and an organic matter powder with a high carbon yield as a carbon source, mixes the two powders as a precursor of zirconium carbide ceramic, and prepares a photocuring 3D printing slurry, which can significantly improve the curing depth of the photocuring 3D printing zirconium carbide-based ultrahigh-temperature ceramic slurry, and is beneficial to quickly printing the zirconium carbide-based ultrahigh-temperature ceramic precursor blank. Further, in combination with reasonable selection of sintering temperature, the present application can realize the preparation of the zirconium carbide-based ultrahigh-temperature ceramic member. BRIEF DESCRIPTION OF DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the description of the embodiments and the comparative examples will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments and comparative examples of the present application, and other drawings can also be obtained by those skilled in the art without creative labor. Among them:

[0027] Figure 1 The exposure dose-curing depth relationship of the slurry in Example 1 of the present application.

[0028] Figure 2 The XRD pattern of the sample after sintering at 1600 DEG C in Example 1.

[0029] Figure 3 The XRD pattern of the sample after sintering at 1500 DEG C in Comparative Example 2. DETAILED DESCRIPTION

[0030] In order to make the above-mentioned objects, features and advantages of the present application more apparent and easy to understand, the specific embodiments of the present application will be described in detail in the following with reference to the description of the embodiments.

[0031] In the following description, many specific details are set forth in order to provide a thorough understanding of the present application, but the present application can also be implemented in other ways different from those described herein, and those skilled in the art can make similar generalizations without departing from the connotation of the present application, therefore the present application is not limited to the specific embodiments disclosed below.

[0032] Secondly, the "one embodiment" or "embodiment" referred to herein means that the specific features, structures or characteristics can be included in at least one implementation of the present application. "In one embodiment" appearing in different places in the specification does not mean the same embodiment, nor is it an embodiment that is separate or alternative to other embodiments.

[0033] The raw materials used in the present application are commercially available in the art without special instructions.

[0034] The 3D printer used in the present application is a CeraStation 160 ceramic 3D printer developed by Jiangsu Qiandu Intelligent Manufacturing High-tech Co., Ltd. The thickness of the ceramic printing layer used for testing is 50 μm, the exposure intensity is 80, and the exposure time is 10 s.

[0035] Example 1

[0036] The present embodiment provides a preparation method of a photocured 3D printed zirconium carbide-based ultrahigh-temperature ceramic slurry, in particular:

[0037] (1) Mixing zirconium oxide and polyacrylonitrile powder:

[0038] 20.0 g of zirconium oxide powder (with a median particle size of 200 nm, accounting for 57.8% of the total mass of the mixed powder) and 14.6 g of polyacrylonitrile powder (with a median particle size of 20 microns, accounting for 42.2% of the total mass of the mixed powder) are mixed by wet ball milling. The material of the ball mill tank is polytetrafluoroethylene; the ball milling medium is ethanol; the material of the ball milling beads is zirconium oxide, and the diameter of the ball milling beads is 3 mm; the rotation speed during ball milling is 300 rpm, and the ball milling time is 12 h; the mass ratio of the mixed powder to the ball milling beads is 1 g of mixed powder: 5 g of ball milling beads; and the total mass of the mixed powder to the volume of ethanol is 1 g of mixed powder: 2 mL of ethanol. After the ball milling mixing is completed, the mixed powder is obtained after drying, grinding, and sieving. The drying temperature is 90°C, the drying time is 48 h, and the mesh size of the sieve is 150 mesh.

[0039] (2) Preparation of photocured slurry:

[0040] Mixing the photosensitive resin active diluent and the photoinitiator to obtain a resin mixture. 50 g of photosensitive resin active diluent trimethylolpropane triacrylate (accounting for 97.1% of the total mass of the resin mixture) and 1.5 g of photoinitiator bis(2,4,6-trimethylbenzoyl) diphenyl phosphine oxide (accounting for 2.9% of the total mass of the resin mixture) are added to a light-shielding bottle. The photoinitiator is completely dissolved in the photosensitive resin active diluent by magnetic stirring to obtain the resin mixture.

[0041] 10.80 g of the resin mixture (accounting for 33.9% of the total mass of the slurry), 20.20 g of the mixed powder of zirconium oxide and polyacrylonitrile (accounting for 63.5% of the total mass of the slurry), and 0.82 g of the dispersant SP769Z (accounting for 2.6% of the total mass of the slurry) are placed in a plastic tank, 160 g of zirconium oxide ball milling beads are added, and ball milling is performed at a rotation speed of 300 revolutions per minute for 12 h to prepare the photocured slurry.

[0042] The slurry is subjected to a curing depth test, and the results are shown in Table 1. Figure 1The horizontal axis of the exposure dose-curing depth graph is exposure dose (incident energy per unit area), and the vertical axis is curing depth. Higher curing depth at the same exposure dose indicates better light-curing properties of the slurry; lower exposure dose required at the same curing depth indicates better light-curing properties. The exposure dose of 400 mJ / cm 2 is 110 microns; the exposure dose of 650 mJ / cm 2 is 140 microns. The curing depth of the slurry is higher than 100 microns, which is suitable for light-curing 3D printing.

[0043] (3) Light-curing 3D printing:

[0044] An industrial-grade ceramic printer CeraStation160 (Jiangsu Qiandu Intelligent Manufacturing Technology Co., Ltd.) was used, with an exposure intensity of 80, a single exposure time of 10 seconds, a single layer thickness of 50 microns, and a printed cube sample with a side length of 1 cm.

[0045] (4) Pyrolysis:

[0046] The printed sample was placed in an alumina crucible and embedded in zirconia ceramic powder. The crucible was placed in a tube furnace and heated from room temperature to 600°C at a rate of 1°C / min under an argon atmosphere. During the heating process, the sample was kept at 100, 300, 400, and 600°C for 1 hour, respectively. The furnace was cooled to room temperature.

[0047] (5) Carbothermal reduction reaction:

[0048] After pyrolysis, the carbothermal reduction reaction was carried out under an argon atmosphere at a temperature of 1600°C for 1 hour.

[0049] Figure 2 The XRD pattern of the sample after carbothermal reduction reaction is shown. The horizontal axis is the angle (2θ), and the vertical axis is the intensity. The XRD results show that the crystal phase after carbothermal reduction reaction is zirconium carbide.

[0050] Example 2

[0051] The difference between this example and Example 1 is that the ratio of zirconia powder and polyacrylonitrile powder in the preparation process of the mixed powder in step (1) is changed. The zirconia powder is 50g, and the polyacrylonitrile powder is 44g (the zirconia powder and the polyacrylonitrile powder account for 53.2% and 47.8% of the total mass of the mixed powder, respectively).

[0052] Example 3

[0053] The difference between the present embodiment and embodiment 1 is that the ratio of zirconium oxide powder and polyacrylonitrile powder in the preparation process of the mixed powder of zirconium oxide and polyacrylonitrile in step (1) is changed. The mass of zirconium oxide powder is 50 g, and the mass of polyacrylonitrile powder is 61 g (the mass of zirconium oxide powder and polyacrylonitrile powder accounts for 82.0% and 18.0% of the total mass of the mixed powder, respectively).

[0054] Comparative example 1

[0055] The relationship between the curing depth and the exposure energy of the photocuring slurry prepared by using the zirconium carbide ceramic powder was tested.

[0056] The difference between the present embodiment and embodiment 1 is that the ratio of zirconium oxide powder and polyacrylonitrile powder in the preparation process of the mixed powder of zirconium oxide and polyacrylonitrile in step (1) is changed. The mass of zirconium oxide powder is 50 g, and the mass of polyacrylonitrile powder is 61 g (the mass of zirconium oxide powder and polyacrylonitrile powder accounts for 82.0% and 18.0% of the total mass of the mixed powder, respectively). 2 The test results show that the two slurries cannot be cured to form a thin film with a certain strength under the condition that the incident energy is 400-800 mJ / cm

[0057] Comparative example 2

[0058] The difference between the present embodiment and embodiment 1 is that the sintering temperature in step (5) is set to 1500℃. Figure 3 The XRD test results show that the main phase is zirconium oxide, and only a small amount of zirconium carbide exists. Compared with the XRD test results of embodiment 1, Figure 2 Compared with the XRD test results of embodiment 1, Figure 3 No zirconium carbide-based superhigh-temperature ceramic phase is obtained, which highlights the importance of controlling the sintering temperature.

[0059] In summary, the present application uses zirconium oxide as a zirconium source and a high-carbon-yield organic powder as a carbon source, mixes the two powders as a precursor of zirconium carbide ceramic, and prepares a photocuring 3D printing slurry, which can significantly improve the curing depth of the photocuring 3D printing zirconium carbide-based superhigh-temperature ceramic slurry and is conducive to the rapid printing of the zirconium carbide-based superhigh-temperature ceramic precursor blank. Further, the present application, in combination with the reasonable selection of the sintering temperature, can realize the preparation of the zirconium carbide-based superhigh-temperature ceramic member.

[0060] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present application but not limit the present application. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or replaced equivalently without departing from the spirit and scope of the present application, and all of them should be covered in the scope of the claims of the present application.

Claims

1. A photopolymerizable 3D printing slurry for zirconium carbide-based ultra-high temperature ceramics, characterized in that: include, Zirconia powder, polyacrylonitrile powder, photosensitive resin reactive diluent, dispersant, photoinitiator; The zirconium oxide powder and polyacrylonitrile powder account for 30-65% of the total mass of the slurry; the photosensitive resin mixture formed by mixing the photosensitive resin active diluent and the photoinitiator accounts for 30-65% of the total mass of the slurry; and the dispersant accounts for 1-5% of the total mass of the slurry.

2. The photopolymerizable 3D printing zirconium carbide-based ultra-high temperature ceramic slurry as described in claim 1, characterized in that: The zirconium oxide powder has a particle size of 0.05–10 micrometers, the polyacrylonitrile powder has a particle size of 0.1–80 micrometers, the photosensitive resin active diluent is trimethylolpropane triacrylate, the dispersant is SP-769Z, and the photoinitiator is bis(2,4,6-trimethylbenzoyl)diphenylphosphine oxide.

3. The photopolymerizable 3D printing zirconium carbide-based ultra-high temperature ceramic slurry as described in claim 2, characterized in that: The mass ratio of zirconium oxide to polyacrylonitrile powder is 1:0.5 to 2.

4. The preparation method according to claim 2, characterized in that: The mass ratio of the photosensitive resin reactive diluent to the photoinitiator is 100:1 to 5.

5. The method for preparing photopolymerizable 3D printing zirconium carbide-based ultra-high temperature ceramic slurry as described in claims 1-4, characterized in that: include, Zirconia and polyacrylonitrile powders were mixed by wet ball milling, and then dried, ground, and sieved to obtain a mixed powder. A photosensitive resin mixture is obtained by mixing a photosensitive resin reactive diluent and a photoinitiator. The powder, photosensitive resin mixture and dispersant are mixed to form a zirconium carbide-based ultra-high temperature ceramic slurry.

6. The preparation method according to claim 5, characterized in that: In the wet ball milling process, the milling jar is made of polytetrafluoroethylene or nylon; the milling medium is ethanol; the milling beads are made of zirconium oxide and have a diameter of 3–10 mm; the milling speed is 150–500 rpm and the milling time is 2–24 h; the mass ratio of the mixed powder to the milling beads is 1:1–10; and the total mass ratio of the mixed powder to the volume ratio of ethanol is 1:1–5.

7. The preparation method according to claim 5, characterized in that: The mixture is dried, ground, and sieved to obtain a mixed powder. The drying temperature is 80-90℃, the drying time is 24-48h, and the sieve mesh size is 100-150 mesh.

8. The application of the zirconium carbide-based ultra-high temperature ceramic slurry as described in any one of claims 1 to 4 in photopolymerization 3D printing of zirconium carbide-based ultra-high temperature ceramics.

9. The application as described in claim 8, characterized in that: The process includes printing zirconium carbide-based ultra-high temperature ceramic slurry using a photopolymerization 3D printer to form a zirconium carbide-based ultra-high temperature ceramic precursor blank; and sequentially cleaning, degreasing, and high-temperature sintering the printed blank to obtain zirconium carbide-based ultra-high temperature ceramic. The degreasing process involves placing the printed sample in an alumina crucible and embedding it in zirconia ceramic powder. The crucible is then placed in a tube furnace and heated from room temperature to 600°C at a heating rate of 0.05–5°C / min under an argon atmosphere. During this process, the temperature is maintained at 100, 300, 400, and 600°C for 1–2 hours, respectively, and then cooled to room temperature.

10. The application as described in claim 8 or 9, characterized in that: The high-temperature sintering is pressureless sintering or gas pressure sintering, and the sintering temperature is not lower than 1600℃.

Images