CN115448734A - 3D printing ceramic composite material and preparation method and application thereof - Google Patents

Abstract

The invention discloses a 3D printing ceramic composite material and its preparation method and application. The preparation method comprises the following steps: each raw material is counted in parts by weight; (1) 0.5 to 20 parts of a photopolymerizable prepolymer, 3 ~35 parts of photopolymerizable monomer, 0.5~5 parts of photoinitiator, 0.5~10 parts of up-conversion luminescent material, 0.25~5 parts of surfactant and 60~95 parts of ceramic powder are mixed to prepare 3D printing ceramic ink; (2) Perform near-infrared light-assisted ink direct writing 3D printing on ceramic ink according to a predetermined program structure to obtain a three-dimensional ceramic structure preform; (3) degrease and sinter the preform to obtain a ceramic device, that is, the 3D Print ceramic composites. The ceramic composite material obtained by the invention has specific fluorescence characteristics under near-infrared laser excitation, and can be widely used in the fields of anti-counterfeiting, temperature detection and the like.

Description

A kind of 3D printing ceramic composite material and its preparation method and application

technical field

The invention relates to the technical field of luminescent ceramics, in particular to a 3D printing ceramic composite material and its preparation method and application.

Background technique

Up-conversion luminescent materials are luminescent materials that can emit visible light under the excitation of near-infrared light. The luminescent center absorbs two or more photons successively, relaxes to the luminescent energy level through a non-radiative transition, and then transitions to the ground state energy level to emit visible photons. Up-conversion luminescence has very good optical properties, such as extremely weak background fluorescence, large anti-Stokes effect, narrow emission bandwidth, less photobleaching, stable fluorescence, less light scattering and deeper tissue penetration , has a good development prospect in three-dimensional display, laser anti-counterfeiting, solar cells, bioluminescence marking and medicine. But at present, it is mainly limited to the preparation of powders, which can no longer meet the needs of people's three-dimensional up-conversion light-emitting devices. Many fields urgently need three-dimensional structures to expand the application of up-conversion light-emitting devices.

Compared with traditional ceramic manufacturing technology, additive manufacturing technology allows complex physical models to be constructed according to individual needs, without relying on molds and complex machining, and can print ceramics with different structures according to the performance requirements of different materials, greatly broadening the application field of ceramics . Ink direct writing technology is based on the computer-aided design of the three-dimensional structure of the sample, and according to the equipment used, the ink is extruded from the nozzle with pneumatic or mechanical power to form a linear fluid, and each layer of the structure is sequentially formed on the substrate according to the designed graphics . For ink direct-write printing, the ink should have shear-thinning properties and excellent viscoelasticity, showing good flow behavior under shear force. To achieve higher-precision printing, the curing behavior of extruded filaments should be strictly controlled to provide higher shape retention and good bonding between layers. The ink needs to cure quickly after extrusion and keep its shape stable and stable. Stacked layer by layer without collapsing. The lack of in-situ curing in the traditional ink direct writing printing technology limits the complexity of the printed structure, and it is impossible to directly print special-shaped structures without adding support materials. To achieve higher-precision printing, several different curing mechanisms have been explored, including external media assist, electric assist, heat assist, ink freezing assist, etc.; The ability to print more complex ceramic structures without auxiliary support structures remains limited.

In the field of ceramics, traditional anti-counterfeiting technologies mainly include fluorescent anti-counterfeiting and temperature-changing anti-counterfeiting. However, due to the shortcomings of traditional ceramic anti-counterfeiting technologies such as low technical content and easy structural combination, most of the widely used fluorescent anti-counterfeiting materials in the ceramic market only have a single fluorescent anti-counterfeiting function under a single condition. Materials are easily deciphered and counterfeited, which leads to a large number of counterfeit products on the market. In recent years, anti-counterfeiting technology has mainly developed around computer network anti-counterfeiting, physical anti-counterfeiting and material chemical anti-counterfeiting. Therefore, it is of great significance to study a kind of anti-counterfeiting ceramics that can be used in multifunctional applications.

Contents of the invention

Aiming at the above-mentioned problems in the prior art, the present invention provides a 3D printing ceramic composite material and its preparation method and application. The 3D printing ceramic ink of the present invention has good shear thinning characteristics and excellent near-infrared light curing performance, and the preparation method is simple, and the in-situ rapid prototyping of the high-solid-content ceramic ink is realized by using the near-infrared light-assisted ink direct writing technology. 3D printed ceramic composites have specific fluorescence characteristics under near-infrared light, which can be widely used in anti-counterfeiting, temperature detection and other fields.

Technical scheme of the present invention is as follows:

The first object of the present invention is to provide a preparation method of 3D printing ceramic composite material, said preparation method comprising the following steps: each raw material is counted in parts by weight;

(1) 0.5-20 parts of photopolymerizable prepolymer, 3-35 parts of photopolymerizable monomer, 0.5-5 parts of photoinitiator, 0.5-10 parts of up-conversion luminescent material, 0.25-5 parts of surfactant and 60-95 parts of ceramic powder are mixed to prepare 3D printing ceramic ink for direct writing with near-infrared light-assisted ink;

(2) Put the ink in the extrusion syringe of the near-infrared light-assisted direct writing 3D printer, perform centrifugation to remove air bubbles, then control the moving speed of the nozzle, and perform near-infrared light-assisted ink direct writing on the ceramic ink according to the predetermined program structure 3D printing, realizing real-time solidification in situ, and obtaining three-dimensional ceramic structure preforms;

(3) Degreasing and sintering the preform to obtain a ceramic device, that is, the 3D printed ceramic composite material;

The 3D printing ceramic ink assisted by near-infrared light direct writing has the characteristics of shear thinning, and the viscosity at the shear rate of 30s ^-1 is 0.5 to 150 Pa·s; preferably, the viscosity at the shear rate of 30s ^-1 is 10 ~100Pa·s.

In one embodiment of the present invention, in step (1), the preparation method of the 3D printing ceramic ink of near-infrared light-assisted ink direct writing is as follows: each raw material is counted in parts by weight;

① Disperse and mix 0.5-20 parts of photopolymerizable prepolymer, 3-35 parts of photopolymerizable monomer, and 0.5-5 parts of photoinitiator at high speed to obtain a photopolymerization system;

② Disperse and mix the photopolymerization system prepared in step ① with 0.25-5 parts of surfactant and 0.5-10 parts of up-conversion luminescent material at high speed to obtain a photosensitive premixed system;

③ Disperse and mix the photosensitive premix system prepared in step ② with 60-95 parts of ceramic powder at high speed to obtain near-infrared light-assisted ink direct writing 3D printing ceramic ink.

In one embodiment of the present invention, the speed of high-speed dispersion mixing is 1500-3000 r/min, and the ball-to-material ratio is 0.5-30:1.

Preferably, 3-10 parts of photopolymerizable prepolymer; 5-20 parts of photopolymerizable monomer; 1-3 parts of photoinitiator; 2-7 parts of up-conversion material; 1-3 parts of surfactant; 70-90 parts;

In one embodiment of the present invention, the photopolymerizable prepolymer is a resin containing acrylate double bonds;

Preferably, the photopolymerizable prepolymer is urethane acrylate CN8885 NS, aliphatic urethane acrylate CN8011 NS, aliphatic urethane acrylate CN9006 NS, aliphatic urethane acrylate CN9010 NS, and aliphatic urethane acrylate produced by Sartomer. Ester CN996 NS; Aliphatic urethane acrylate 61967, aliphatic urethane acrylate 5104D, epoxy acrylate 621-100, modified epoxy acrylate 6210G, epoxy acrylate 624-100 produced by Changxing Material Industry Co., Ltd. one or more of

In one embodiment of the present invention, the photopolymerizable monomer is a difunctional acrylate monomer, a multifunctional acrylate monomer, an aliphatic epoxy monomer, an oxetane monomer one or more of

Preferably, the photopolymerizable monomer is ditrimethylolpropane tetraacrylate, neopentyl glycol diacrylate, dipentaerythritol hexaacrylate, 1,6-hexanediol diacrylate, trimethylol One or more of propane triacrylate and pentaerythritol triacrylate.

In one embodiment of the present invention, the photoinitiator is bis 2,6-difluoro-3-pyrrole phenyl titanocene, phenyl bis(2,4,6-trimethylbenzoyl) oxidation One of phosphine, 2-isopropylthioxanthone, camphorquinone, [diethyl-(4-methoxybenzoyl)germanyl]-(4-methoxyphenyl)methanone or Various.

In one embodiment of the present invention, the up-conversion luminescent material is one of Yb ³⁺ or Tm ³⁺ doped NaYF ₄ , BaYF ₅ , NaGdF ₄ , LiYF ₄ , NaYbF ₄ , Na ₃ ScF ₆ or There are many kinds, the doping amount of Yb ³⁺ is 0-30%, and the doping amount of Tm ³⁺ is 0.2-3.5%.

Preferably, the up-conversion material is NaYbF ₄ (Tm ³⁺ doping amount is 0.5%), β-NaYF ₄ (Yb ³⁺ doping amount is 20%, Tm ³⁺ doping amount is 0.5%).

In one embodiment of the present invention, the surfactant is one or more of BYK111, BYK168, polyvinylpyridone, KOS110, KOS163, oleic acid, and KH560.

Preferably, the surfactant is one or more of BYK111, BYK168, KOS110, KH560.

In one embodiment of the present invention, the ceramic powder is Al ₂ O ₃ , SiO ₂ , ZrO ₂ , 3Al ₂ O ₃ ·3SiO ₂ , MgAl ₂ O ₃ , hydroxyapatite, calcium phosphate, tricalcium phosphate one or more of.

In one embodiment of the present invention, the particle size of the ceramic powder is 1 nm˜100 μm.

Preferably, the particle diameter of the ceramic powder is 100 nm-20 μm.

In one embodiment of the present invention, in step (2), the slurry is centrifuged to remove air bubbles at a centrifugal rate of 3000-10000 r/min, and the time is 3-15 min;

Preferably, the centrifugation rate is 4500-8000 r/min, and the time is 4-10 minutes.

In one embodiment of the present invention, in step (2), the wavelength of the near-infrared light for direct writing 3D printing assisted by near-infrared light is 780-2500nm; the power of the near-infrared laser is 0.5-50W.

Preferably, the wavelength of the near-infrared light is 980nm; the power of the near-infrared laser is 2-30W.

In one embodiment of the present invention, in step (2), the moving speed of the extrusion nozzle is 0.1-80 mm/s, more preferably 0.8-60 mm/s;

Preferably, the diameter range of the direct writing nozzle is 0.2-5mm, more preferably 0.6-2.5mm;

In one embodiment of the present invention, in step (3), the degreasing temperature is 500-650°C, the degreasing time is 60-240min, and the heating rate to the degreasing temperature is 0.5-2.0°C/min;

Preferably, the degreasing temperature is 550-600°C, the degreasing time is 90-180min, and the heating rate to the degreasing temperature is 1-1.5°C/min;

The sintering temperature is 1100-1750° C., the sintering time is 3-12 hours, and the heating rate to the sintering temperature is 2-15° C./min.

Preferably, the sintering temperature is 1300-1650° C., the sintering time is 5-10 hours, and the heating rate to the sintering temperature is 3-10° C./min.

The second object of the present invention is to provide a 3D printing ceramic composite material prepared by the preparation method.

The present invention has no special requirements on the specific shape and structure of the 3D printing, and the computer program is used to control the printing, and it can be designed according to actual needs, and can be any complex three-dimensional structure.

The third object of the present invention is to provide an application of 3D printed ceramic composite material for anti-counterfeiting or temperature detection.

3D printing ceramic composite materials are used for anti-counterfeiting. Under the excitation of 980nm near-infrared laser, the prepared ceramic composite materials produce visible up-conversion luminescence, and the up-conversion luminescence can be reversibly regulated through color-changing characteristics, and have good physical and chemical stability. It has practical application prospects in the field of anti-counterfeiting.

3D printed ceramic composite materials are used in the field of near-infrared luminescence temperature detection. The ceramic sensor prepared by direct writing with near-infrared auxiliary ink can perform local, non-contact and precise optical measurement, using the 422nm and 451nm in the spectrum when near-infrared light is excited. The function relationship between the intensity ratio of the emission band and the temperature realizes the purpose of temperature measurement, and has the advantages of high accuracy, low cost, and simple detection.

The beneficial technical effects of the present invention are:

The storage modulus of the present invention after in-situ curing under near-infrared light irradiation is greater than 400kPa, and the preform can maintain good macroscopic structural characteristics without structural deformation and collapse.

The ceramic ink provided by the invention has good shear thinning properties and excellent near-infrared light curing performance, and the preparation method is simple, and the in-situ rapid prototyping of the high-solid-content ceramic ink is realized by using the near-infrared light-assisted ink direct writing technology. The prepared up-conversion luminescent ceramics have specific fluorescence characteristics under near-infrared light, and can be widely used in anti-counterfeiting, temperature detection and other fields.

The present invention can prepare complex-shaped upconversion luminescent ceramics with high fidelity; when 3D printing and forming objects with suspended features such as large-span structures and overhanging structures, it is generally necessary to add auxiliary support structures, which limits the design freedom of 3D printing. The present invention makes the ceramic ink have significant shear thinning characteristics and a higher storage modulus (greater than 400kPa) after fast curing by adjusting the contents of ceramic powder, photopolymerizable components, and surfactants in the ink, thereby successfully Prepare independent components with controlled configurations to meet the needs of high aspect ratios, large spans, etc. The advantage of this preparation method is that it solves the problem of deep-layer curing of high-solid content ceramic inks, and can also prepare components with complex shapes without adding support structures. Compared with other technologies, this technology is simple and efficient. Near-infrared light is used to promote crosslinking and curing at room temperature, and multi-scale complex components can be prepared, which broadens the application field of 3D printing technology.

The ceramic composite material of the invention has the characteristics of narrow emission spectrum band, high color purity, wide emission wavelength distribution area, stable physical and chemical properties, long service life and high temperature resistance. Under the excitation of near-infrared laser, it shows bright fluorescent emission, and has high concealment under sunlight, is not easy to imitate, has strong confidentiality, and has reliable anti-counterfeiting effect. Therefore, this material can be used in some applications in the field of infrared anti-counterfeiting.

The ceramic composite material of the present invention can emit a plurality of visible spectral lines, and the intensity ratio of each spectral line is highly sensitive to the base material and its manufacturing process, and the temperature monitoring is realized by using the change of the up-converted luminescent color with the temperature, The method is simple and feasible, and has great application potential in temperature visual indication. The lower phonon energy of the matrix material is conducive to obtaining stronger up-conversion luminescence, which can realize an optical high-temperature sensor with higher operating temperature and up-conversion luminescence efficiency. The prepared up-conversion luminescent ceramic composite material has high mechanical strength, good chemical stability, high damage threshold, simple preparation process, and is more suitable for production and application. Compared with the existing powder and coating films, the present invention can directly use the up-conversion luminescent ceramics for anti-counterfeiting, imaging, etc., and has better physical and chemical stability. The up-conversion luminescent ceramics can be directly recycled and used repeatedly. Further, the service life of the up-conversion functional material is increased.

Description of drawings

Fig. 1 is the ink rheology test figure of embodiment 1-7 of the present invention, uses DHR-2 rheometer to measure, and fixture is cone-plate (25mm diameter, 2 ° taper); Shear rate is raised by 0.01rad/s to 100rad/s; the test temperature is 30°C.

Fig. 2 is the ink real-time rheology test figure of embodiment 1-7 of the present invention, carries out real-time rheology test by the device that adopts near-infrared light and rheometer (HAAKE MARS60 equipped with Rheonaut accessory, Thermo Fisher) to combine , the test temperature is 30°C.

Fig. 3 is the body (3.50mm nozzle) obtained in Example 3 with a curved cantilever structure.

Fig. 4 is obtained in embodiment 4 and has the shape body (0.60mm nozzle) with porous grid structure.

Fig. 5 is obtained in embodiment 5 and has the shape body (0.84mm nozzle) with ring structure.

Fig. 6 has the gear structure body (0.60mm nozzle) that obtains in embodiment 6.

FIG. 7 is an anti-counterfeiting test of the up-conversion luminescent ceramic prepared in Example 1. FIG.

Fig. 8 is an up-conversion emission spectrum of the up-conversion luminescent ceramic prepared in Example 2 under the excitation of 980nm near-infrared laser.

detailed description

The present invention will be specifically described below in conjunction with the accompanying drawings and embodiments.

Example 1

A method for preparing a 3D printed ceramic composite material, specifically comprising the steps of:

In terms of weight fraction, the ink is composed of the following components: 9.5 parts of aliphatic polyurethane acrylate CN996NS produced by Sartomer, 10 parts of 1,6-hexanediol diacrylate, phenyl bis(2,4,6-tri 1.5 parts of methylbenzoyl)phosphine oxide, 76 parts of 0.2μm alumina, 1.5 parts of BYK111, up-converting particle β-NaYF ₄ (Yb ³⁺ doping amount is 20%, Tm ³⁺ doping amount is 0.5%) 1.5 servings.

(1) Add phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide to the mixture of aliphatic urethane acrylate CN996NS and 1,6-hexanediol diacrylate, and use a high-speed disperser Disperse for 3 minutes at a rotating speed of 2000 rpm to obtain a uniform photopolymerization system;

(2) Add up-converting particles β-NaYF ₄ (Yb ³⁺ doping amount is 20%, Tm ³⁺ doping amount is 0.5%) and BYK111 into the photopolymerization system, and use a high-speed disperser at 2000 rpm Disperse for 3 minutes at a rotating speed of 1 to obtain a photosensitive premixed system;

(3) Add powdered alumina to the photosensitive premix system, add zirconia balls with a ball-to-material ratio of 0.5:1, and disperse for 3 minutes at a speed of 2300 rpm with a high-speed disperser to obtain near-infrared light-assisted Ink direct writing 3D printing ceramic ink. The obtained ceramic ink has shear-thinning properties (as shown in Figure 1 ) when subjected to shear force, and the viscosity is 14.9 Pa·s when the shear rate is 30 s ^-1 .

(4) Inject the above-mentioned ink into the barrel of the printer, and centrifuge the barrel at 5000 rpm for 5 minutes to remove the foam; push the extrusion with gas, control the extrusion pressure to 190kPa, and squeeze the ink through a 0.6mm direct writing nozzle The moving speed of the extrusion nozzle is 1.5mm/s, the laser emission structure emits a beam with a wavelength of 980nm, the laser power is 2.7W, and the storage modulus of the ink after real-time curing by near-infrared light is significantly improved (as shown in the figure 2), from 8.29kPa without curing to 4592.14kPa after curing.

Adjust the printing parameters according to the structural design requirements, and use the computer program to control and print out the designed structure. The printing process is assisted by near-infrared light. The controllability promotes rapid in-situ curing of ink to obtain preforms.

The preform was first heated to 550°C at a rate of 1°C/min and held for 3 hours. The degreasing process was carried out in the air; ℃ and keep it warm for 6 hours. Vacuum or protective atmosphere is used for sintering during the sintering process. After degreasing and sintering, an up-conversion luminescent ceramic device with a three-dimensional structure is obtained.

Example 2

A method for preparing a 3D printed ceramic composite material, specifically comprising the steps of:

In parts by weight, the ink is composed of the following components: polyurethane acrylate CN8885 NS 16.5 parts, ditrimethylolpropane tetraacrylate 3 parts, phenyl bis(2,4,6-trimethylbenzoyl) oxidation 1.5 parts of phosphine, 76 parts of 0.5 μm alumina, 1.5 parts of BYK168, 1.5 parts of up-conversion particles β-NaYF ₄ (Yb ³⁺ doping amount is 20%, Tm ³⁺ doping amount is 0.5%).

(1) Add phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide to urethane acrylate CN8885 NS and bistrimethylolpropane tetraacrylate, and use a high-speed disperser at 2000 rpm Disperse for 3 minutes at a rotating speed of 10 minutes to obtain a uniform photopolymerization system;

(2) Add up-converting particles β-NaYF ₄ (Yb ³⁺ doping amount is 20%, Tm ³⁺ doping amount is 0.5%) and BYK168 into the photopolymerization system, and use a high-speed disperser at 2000 rpm Disperse for 3 minutes at a rotating speed of 2000 rpm to obtain a photosensitive premixed system;

(3) Add powdered alumina to the photosensitive premix system, add zirconia balls with a ball-to-material ratio of 0.5:1, and disperse for 3 minutes at a speed of 2300 rpm with a high-speed disperser to obtain near-infrared light-assisted Ink direct writing 3D printing ceramic ink. The obtained ceramic ink has shear-thinning properties (as shown in Figure 1 ) when subjected to shear force, and the viscosity is 15.2 Pa·s when the shear rate is 30 s ^-1 .

(4) inject the above-mentioned ink into the syringe of the printer, and centrifuge the syringe at 5000 rpm for 6 minutes to remove the bubbles; push the extrusion with gas, control the extrusion pressure to 100kPa, and squeeze the ink through a 1.25mm direct writing nozzle The moving speed of the extrusion nozzle is 1mm/s, the laser emission structure emits a beam with a wavelength of 980nm, the laser power is 5.2W, and the storage modulus of the ink after real-time curing by near-infrared light is significantly improved (as shown in Figure 2 Shown), from 7.62kPa without curing to 4224.77kPa after curing.

Adjust the printing parameters according to the structural design requirements, and use the computer program to control and print out the designed structure. The printing process is assisted by near-infrared light. The controllability promotes rapid in-situ curing of ink to obtain preforms.

The preform was first heated to 600°C at a rate of 1°C/min and held for 3 hours, and the degreasing process was carried out in the air; the sintering method was: the degreased formed part was heated to 1600°C at a rate of 10°C/min ℃ and keep it warm for 5 hours. Vacuum or protective atmosphere is used for sintering during the sintering process. After degreasing and sintering, an up-conversion luminescent ceramic device with a three-dimensional structure is obtained.

Example 3

A method for preparing a 3D printed ceramic composite material, specifically comprising the steps of:

In parts by weight, the ink consists of the following components: 10.5 parts of aliphatic urethane acrylate 61967, 9.5 parts of dipentaerythritol hexaacrylate, [diethyl-(4-methoxybenzoyl) germanyl]-(4 - 1 part of methoxyphenyl) ketone, 76 parts of 0.5 μm alumina, 1.5 parts of KOS110, up-conversion particle β-NaYF ₄ (Yb ³⁺ doping amount is 20%, Tm ³⁺ doping amount is 0.5% ) 1.5 parts.

(1) Add [diethyl-(4-methoxybenzoyl)germanium]-(4-methoxyphenyl)methanone to aliphatic urethane acrylate 61967 and dipentaerythritol hexaacrylate to mix, Use a high-speed disperser to disperse for 3 minutes at a speed of 2000 rpm to obtain a uniform photopolymerization system;

(2) Add up-converting particles β-NaYF ₄ (Yb ³⁺ doping amount is 20%, Tm ³⁺ doping amount is 0.5%) and KOS110 into the photopolymerization system, and use a high-speed disperser at 2000 rpm Disperse for 3 minutes at a rotating speed of 1 to obtain a photosensitive premixed system;

(3) Add powdered alumina to the photosensitive premix system, add zirconia balls with a ball-to-material ratio of 0.5:1, and disperse for 3 minutes at a speed of 2300 rpm with a high-speed disperser to obtain near-infrared light-assisted Ink direct writing 3D printing ceramic ink. The obtained ceramic ink has shear thinning characteristics (as shown in Fig. 1 ) when subjected to shear force, and the viscosity is 23.8 Pa·s when the shear rate is 30 s ^-1 .

(4) Inject the above-mentioned ink into the barrel of the extruded 3D printer, and centrifuge the syringe at 5000 rpm for 8 minutes to remove the bubbles; push the extrusion with gas, control the extrusion pressure to be 60kPa, and the ink passes through the 3.50mm straight Writing nozzle extrusion, the moving speed of the extrusion nozzle is 0.8mm/s, the laser emitting structure emits a beam with a wavelength of 980nm, the laser power is 20W, and the storage modulus of the ink after real-time curing by near-infrared light is significantly improved ( As shown in Figure 2), from 8.66kPa without curing to 4798.79kPa after curing.

Adjust the printing parameters according to the structural design requirements, and use the computer program to control and print out the designed curved cantilever structure (the curved cantilever structure is shown in Figure 3). The printing process is assisted by near-infrared light. By simultaneously lifting the direct writing nozzle and the near-infrared spot, The high penetration and controllability of near-infrared light is used to promote rapid in-situ curing of the ink to obtain a preform.

The preform was first heated to 600°C at a rate of 1°C/min and held for 3 hours, and the degreasing process was carried out in the air; the sintering method was: the degreased formed part was heated to 1600°C at a rate of 10°C/min ℃ and keep it warm for 5 hours. Vacuum or protective atmosphere is used for sintering during the sintering process. After degreasing and sintering, an up-conversion luminescent ceramic device with a three-dimensional structure is obtained.

Example 4

A method for preparing a 3D printed ceramic composite material, specifically comprising the steps of:

In parts by weight, the ink is composed of the following components: 5 parts of modified epoxy acrylate 6210G, 7.8 parts of pentaerythritol triacrylate, 2 parts of bis-2,6-difluoro-3-pyrrole phenyl titanocene, 2 μm oxidation 82 parts of aluminum, 1.7 parts of BYK168, 1.5 parts of up-converting particles BaYF ₅ (Yb ³⁺ doping amount is 30%, Tm ³⁺ doping amount is 1%).

(1) Add bis-2,6-difluoro-3-pyrrole phenyl titanocene to modified epoxy acrylate 6210G and pentaerythritol triacrylate, and use a high-speed disperser to disperse at a speed of 2000 rpm for 3 Minutes to obtain a uniform photopolymerization system;

(2) Add up-converting particles BaYF ₅ (Yb ³⁺ doping amount is 30%, Tm ³⁺ doping amount is 1%) and BYK168 into the photopolymerization system, and use a high-speed disperser at a speed of 2000 rpm Disperse at low temperature for 3 minutes to obtain a photosensitive premixed system;

(3) Add powdered alumina to the photosensitive premix system, add zirconia balls with a ball-to-material ratio of 1:1, and disperse for 4 minutes at a speed of 2500 rpm with a high-speed disperser to obtain near-infrared light-assisted Ink direct writing 3D printing ceramic ink. The obtained ceramic ink has shear-thinning properties (as shown in Figure 1 ) when subjected to shear force, and the viscosity is 28.4 Pa·s when the shear rate is 30 s ^-1 .

(4) Inject the above-mentioned ink into the barrel of the extruded 3D printer, centrifuge the syringe at 6000 rpm for 7 minutes, and remove the foam; push the extrusion with gas, control the extrusion pressure to be 530kPa, and the ink passes through a 0.60mm straight Writing nozzle extrusion, the moving speed of the extrusion nozzle is 60mm/s, the laser emitting structure emits a beam with a wavelength of 980nm, the laser power is 30.2W, and the storage modulus of the ink after real-time curing by near-infrared light is significantly improved ( As shown in Figure 2), from 9.87kPa without curing to 5469.24kPa after curing.

Adjust the printing parameters according to the structural design requirements, and use the computer program to control the printing of the designed porous grid structure (the porous grid structure is shown in Figure 4). The printing process is assisted by near-infrared light, and the direct writing nozzle and the near-infrared The light spot uses the high penetration and controllability of near-infrared light to promote rapid in-situ curing of the ink to obtain a preform.

The preform was first heated to 600°C at a rate of 1.5°C/min and held for 2.5 hours. The degreasing process was carried out in air; 1600°C and heat preservation for 6 hours. Vacuum or protective atmosphere is used for sintering during the sintering process. After degreasing and sintering, an up-conversion luminescent ceramic device with a three-dimensional structure is obtained.

Example 5

A method for preparing a 3D printed ceramic composite material, specifically comprising the steps of:

In parts by weight, the ink is composed of the following components: 3 parts of epoxy acrylate 624-100, 6.7 parts of pentaerythritol triacrylate, 2 parts of bis-2,6-difluoro-3-pyrrolephenyl titanocene, 0.5 μm 84 parts of 8% yttria-stabilized zirconia, 1.8 parts of oleic acid, and 2.5 parts of up-conversion particle LiYF ₄ (Yb ³⁺ doping amount is 25%, Tm ³⁺ doping amount is 1%).

(1) Add bis-2,6-difluoro-3-pyrrole phenyl titanocene to epoxy acrylate 624-100 and pentaerythritol triacrylate, and use a high-speed disperser to disperse at a speed of 2000 rpm for 3 Minutes to obtain a uniform photopolymerization system;

(2) Add the up-conversion particles LiYF ₄ (Yb ³⁺ doping amount is 25%, Tm ³⁺ doping amount is 1%) and oleic acid into the photopolymerization system, and use a high-speed disperser at 2000 rpm Disperse for 3 minutes at a rotating speed to obtain a photosensitive premixed system;

(3) Add 8% yttria-stabilized zirconia powder into the photosensitive premix system, add zirconia balls with a ball-to-material ratio of 1:1, and disperse for 4 minutes at a speed of 2500 rpm with a high-speed disperser, Get near-infrared light assisted ink direct writing 3D printing ceramic ink. The obtained ceramic ink has shear-thinning properties when subjected to shear force (as shown in Figure 1), and the viscosity is 23.1 Pa·s when the shear rate is 30 s ^-1 .

(4) Inject the above-mentioned ink into the barrel of the printer, and centrifuge the barrel at 7000 rpm for 8 minutes to remove the foam; push the extrusion with gas, control the extrusion pressure to 220kPa, and squeeze the ink through a 0.84mm direct writing nozzle The moving speed of the extrusion nozzle is 5mm/s, the laser emission structure emits a beam with a wavelength of 980nm, the laser power is 8.5W, and the storage modulus of the ink after real-time curing by near-infrared light is significantly improved (as shown in Figure 2 Shown), from 9.38kPa without curing to 5198.30kPa after curing.

Adjust the printing parameters according to the structural design requirements, and use the computer program to control and print out the designed ring structure (the ring component is shown in Figure 5). The printing process is assisted by near-infrared light. The high penetration and controllability of infrared light promotes rapid in-situ curing of inks to obtain preforms.

The preform was first heated to 600°C at a rate of 1.2°C/min and held for 2.5 hours. The degreasing process was carried out in air; 1480°C and heat preservation for 5 hours. Vacuum or protective atmosphere is used for sintering during the sintering process. After degreasing and sintering, an up-conversion luminescent ceramic device with a three-dimensional structure is obtained.

Example 6

A method for preparing a 3D printed ceramic composite material, specifically comprising the steps of:

In parts by weight, the ink is composed of the following components: 4 parts of aliphatic urethane acrylate CN9006 NS, 5.7 parts of trimethylolpropane triacrylate, bis 2,6-difluoro-3-pyrrole phenyl titanocene 2 19 parts of 0.3μm 3% yttria-stabilized zirconia, 65 parts of 1μm alumina, 1.8 parts of KOS110, up-conversion particle NaGdF ₄ (Yb ³⁺ doping amount is 15%, Tm ³⁺ doping amount is 2% ) 2.5 parts.

(1) Add bis-2,6-difluoro-3-pyrrole phenyl titanocene to aliphatic urethane acrylate CN9006 NS and trimethylolpropane triacrylate, and use a high-speed disperser at 2000 rpm Disperse for 3 minutes at a rotating speed to obtain a uniform photopolymerization system;

(2) Add up-conversion particles NaGdF ₄ (Yb ³⁺ doping amount is 15%, Tm ³⁺ doping amount is 2%) and KOS110 into the photopolymerization system, and use a high-speed disperser at a speed of 2000 rpm Disperse at low temperature for 3 minutes to obtain a photosensitive premixed system;

(3) Add 3% yttria-stabilized zirconia and alumina mixed powder into the photosensitive premix system, add zirconia balls with a ball-to-material ratio of 2:1, and use a high-speed disperser at a speed of 2600 rpm Disperse for 5 minutes to obtain near-infrared light-assisted ink direct writing 3D printing ceramic ink. The obtained ceramic ink has shear thinning characteristics (as shown in Fig. 1 ) when subjected to shear force, and the viscosity is 34.2 Pa·s when the shear rate is 30 s ^-1 .

(4) Inject the above-mentioned ink into the barrel of the printer, and centrifuge the barrel at 7200 rpm for 8 minutes to defoam; push the extrusion with gas, control the extrusion pressure to 410kPa, and squeeze the ink through a 0.60mm direct writing nozzle The moving speed of the extrusion nozzle is 10mm/s, the laser emitting structure emits a beam with a wavelength of 980nm, the laser power is 8.7W, and the storage modulus of the ink after real-time curing by near-infrared light is significantly improved (as shown in Figure 2 Shown), from 10.30kPa without curing to 5708.03kPa after curing.

Adjust the printing parameters according to the structural design requirements, and use the computer program to control and print out the designed gear structure (the gear components are shown in Figure 6). The printing process is assisted by near-infrared light. The high penetration and controllability of infrared light promotes rapid in-situ curing of inks to obtain preforms.

The preform was first heated to 600°C at a rate of 1.5°C/min and held for 2 hours. The degreasing process was carried out in the air; ℃ and keep it warm for 5 hours. Vacuum or protective atmosphere is used for sintering during the sintering process. After degreasing and sintering, an up-conversion luminescent ceramic device with a three-dimensional structure is obtained.

Example 7

A method for preparing a 3D printed ceramic composite material, specifically comprising the steps of:

In parts by weight, the ink is composed of the following components: 0.5 parts of aliphatic urethane acrylate 5104D, 3.4 parts of 1,6-hexanediol diacrylate, phenyl bis(2,4,6-trimethylbenzoyl ) 0.6 parts of phosphine oxide, 52 parts of 10 μm alumina, 24 parts of 2 μm alumina, 18 parts of 0.5 μm alumina, 0.9 parts of BYK111, 0.6 parts of up-conversion particle NaYbF ₄ (Tm ³⁺ doping amount is 0.5%).

(1) Add phenyl bis(2,4,6-trimethylbenzoyl) phosphine oxide to aliphatic urethane acrylate 5104D and 1,6-hexanediol diacrylate, and use a high-speed disperser at 2000 Disperse for 3 minutes at a rotating speed of rpm to obtain a uniform photopolymerization system;

(2) Add the up-converting particles NaYbF ₄ (Tm ³⁺ doping amount is 0.5%) and BYK111 into the photopolymerization system, and disperse at a speed of 2000 rpm for 3 minutes with a high-speed disperser to obtain a photosensitive premixed system ;

(3) Add alumina mixed powder to the photosensitive premix system, add zirconia balls with a ball-to-material ratio of 4:1, and disperse for 5 minutes at a speed of 3000 rpm with a high-speed disperser to obtain near-infrared light Auxiliary ink direct writing 3D printing ceramic ink. The obtained ceramic ink has shear-thinning properties (as shown in Fig. 1 ) when subjected to shear force, and the viscosity is 55.6 Pa·s when the shear rate is 30 s ^-1 .

(4) Inject the above-mentioned ink into the barrel of the printer, and centrifuge the barrel at 8000 rpm for 9 minutes to defoam; push the extrusion with gas, control the extrusion pressure to 260kPa, and squeeze the ink through a 2.45mm direct writing nozzle The moving speed of the extrusion nozzle is 3mm/s, the laser emitting structure emits a beam with a wavelength of 980nm, the laser power is 16.8W, and the storage modulus of the ink after real-time curing by near-infrared light is significantly improved (as shown in Figure 2 Shown), from 12.89kPa without curing to 7145.37kPa after curing.

Adjust the printing parameters according to the structural design requirements, and use the computer program to control and print out the designed structure. The printing process is assisted by near-infrared light. The controllability promotes rapid in-situ curing of ink to obtain preforms.

The preform was first heated to 600°C at a rate of 1.5°C/min and held for 2 hours. The degreasing process was carried out in the air; ℃ and keep it warm for 6 hours. Vacuum or protective atmosphere is used for sintering during the sintering process. After degreasing and sintering, an up-conversion luminescent ceramic device with a three-dimensional structure is obtained.

A larger solid content increases the viscosity of the ink, affecting high-throughput printing. The higher the solid content, in addition to the increase in the ink viscosity, it will occupy the content of the photocurable resin, which will have a greater impact on the curing performance, and the strength of the cured body will be low. After a large number of experimental verifications, only through the reasonable regulation of the above parameters can the effect of multi-scale, unsupported and fast in-situ printing be realized at the same time. The following is illustrated by Comparative Example 1.

Comparative example 1

A preparation method of a ceramic composite material, specifically comprising the steps of:

In parts by weight, the ceramic ink consists of the following components: 2.4 parts of 1,6-hexanediol diacrylate, 0.6 parts of phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, 10 μm oxide 53.0 parts of aluminum, 24.5 parts of 2 μm alumina, 18.0 parts of 0.5 μm alumina, 0.9 parts of BYK111, 0.6 parts of up-conversion particles NaYbF ₄ (Tm ³⁺ doping amount is 0.5%).

(1) Add phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide to 1,6-hexanediol diacrylate, and disperse at a speed of 2000 rpm using a high-speed disperser 3 minutes to obtain a uniform photopolymerization system;

(2) Add the up-converting particles NaYbF ₄ (Tm ³⁺ doping amount is 0.5%) and BYK111 into the photopolymerization system, and disperse at a speed of 2000 rpm for 3 minutes with a high-speed disperser to obtain a photosensitive premixed system ;

(3) Add alumina mixed powder to the photosensitive premix system, add zirconia balls with a ball-to-material ratio of 4:1, and disperse for 6 minutes at a speed of 3000 rpm with a high-speed disperser. Due to the powder content If it is too high, the viscosity of the obtained ceramic ink is too high, and the viscosity is 165.8 Pa·s when the shear rate is 30s ^-1 , and a printable near-infrared light-assisted ink direct writing ceramic ink cannot be obtained.

Application example 1

Put the sintered up-conversion luminescent ceramic material obtained in Implementation 1 under a 980nm near-infrared laser, and the prepared ceramic composite material produces visible up-conversion luminescence, blue-violet light visible to the naked eye, and its up-conversion luminescence can be reversibly regulated through color-changing properties , has good physical and chemical stability, and after the near-infrared laser is turned off, the up-conversion luminescent ceramics show the intrinsic color of the ceramics (as shown in Figure 7). The up-conversion luminescent ceramic prepared by the method of the invention is different from ceramics prepared by other additive manufacturing techniques, has the performance of up-conversion luminescence, and has practical application prospects in ceramic devices in the field of anti-counterfeiting.

Application example 2

The sintered up-conversion luminescent ceramic composite material obtained in Example 2 can be applied to the field of near-infrared luminescence temperature detection, and the ceramic sensor prepared by direct writing with near-infrared assisted ink can perform local, non-contact and precise optical measurement. The function relationship between the intensity ratio of the emission bands at 422nm and 451nm in the spectrum when excited by near-infrared light and temperature is used for temperature sensing (as shown in Figure 8), which has the advantages of high accuracy, low cost, and simple detection.

The above is only a preferred embodiment of the present invention, it should be pointed out that, for those of ordinary skill in the art, without departing from the principle of the present invention, some improvements and modifications can also be made, and these improvements and modifications can also be made. It should be regarded as the protection scope of the present invention.

Claims (10)

1. The preparation method of the 3D printing ceramic composite material is characterized by comprising the following steps: the raw materials are counted by weight;

(1) Mixing 0.5-20 parts of photopolymerisable prepolymer, 3-35 parts of photopolymerisable monomer, 0.5-5 parts of photoinitiator, 0.5-10 parts of upconversion luminescent material, 0.25-5 parts of surfactant and 60-95 parts of ceramic powder to prepare the near-infrared light auxiliary ink direct-writing 3D printing ceramic ink;

(2) Placing the ink in a material extruding needle cylinder of a near-infrared light assisted direct-writing type 3D printer, centrifuging to remove bubbles, controlling the moving speed of a nozzle, performing near-infrared light assisted ink direct-writing 3D printing on the ceramic ink according to a preset program structure, and realizing in-situ real-time curing to obtain a three-dimensional ceramic structure preformed piece;

(3) Degreasing and sintering the preformed piece to obtain a ceramic device, namely the 3D printing ceramic composite material;

near-infrared light assisted ink direct writing 3D printing ceramic ink shear rate of 30s ^-1 The viscosity is 0.5 to 150 pas.

2. The preparation method according to claim 1, wherein in the step (1), the 3D printing ceramic ink for the direct writing of the near infrared light-assisted ink is prepared by: the raw materials are counted by weight;

(1) dispersing and mixing 0.5-20 parts of photopolymerisable prepolymer, 3-35 parts of photopolymerisable monomer and 0.5-5 parts of photoinitiator at a high speed to obtain a photopolymerisable system;

(2) dispersing and mixing the photopolymerization system prepared in the step (1), 0.25-5 parts of surfactant and 0.5-10 parts of up-conversion luminescent material at a high speed to obtain a photosensitive premixed system;

(3) and (3) dispersing and mixing the photosensitive premixed system prepared in the step (2) and 60-95 parts of ceramic powder at a high speed to obtain the near infrared light auxiliary ink direct-writing 3D printing ceramic ink.

3. The preparation method according to claim 1 or 2, wherein the photopolymerizable prepolymer is a resin containing an acrylate double bond; the photopolymerizable monomer is one or more of a bifunctional acrylate monomer, a multifunctional acrylate monomer, an ester ring epoxy monomer and an oxetane monomer; the photoinitiator is one or more of bis (2, 6-difluoro-3-pyrrol-phenyl) titanocene, phenyl bis (2, 4, 6-trimethyl benzoyl) phosphine oxide, 2-isopropyl thioxanthone, camphorquinone and [ diethyl- (4-methoxybenzoyl) germanium ] - (4-methoxyphenyl) methanone.

4. The method according to claim 1 or 2, wherein the up-converting luminescent material is Yb ³⁺ Or Tm ³⁺ Doped NaYF ₄ 、BaYF ₅ 、NaGdF ₄ 、LiYF ₄ 、NaYbF ₄ 、Na ₃ ScF ₆ One or more of (b), yb ³⁺ The doping amount is 0-30%, tm ³⁺ The doping amount is 0.2-3.5%; the surface activityThe sex agent is one or more of BYK111, BYK168, polyvinyl pyridone, KOS110, KOS163, oleic acid, KH 560.

5. The method according to claim 1 or 2, wherein the ceramic powder is Al ₂ O ₃ 、SiO ₂ 、ZrO ₂ 、3Al ₂ O ₃ ·3SiO ₂ 、MgAl ₂ O ₃ One or more of hydroxyapatite, calcium phosphate and tricalcium phosphate.

6. The method according to claim 5, wherein the ceramic powder has a particle size of 1nm to 100 μm.

7. The preparation method according to claim 1, wherein in the step (2), the wavelength of the near-infrared light for the direct-writing 3D printing of the near-infrared light assisted ink is 780 to 2500nm; the power of the near-infrared laser is 0.5-50W.

8. The method according to claim 1, wherein in the step (3), the degreasing temperature is 500 to 650 ℃, the degreasing time is 60 to 240min, and the heating rate for heating to the degreasing temperature is 0.5 to 2.0 ℃/min; the sintering temperature is 1100-1750 ℃, the sintering time is 3-12 h, and the heating rate of heating to the sintering temperature is 2-15 ℃/min.

9. A 3D printed ceramic composite material prepared by the preparation method of claim 1.

10. Use of the 3D printed ceramic composite material according to claim 9 for forgery prevention or temperature detection.

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