KR20230081742A - Method for manufacturing a ceramic structure using a binder jetting 3D printing method, and a ceramic structure manufactured using a binder jetting 3D printing method - Google Patents

Abstract

A method for manufacturing a ceramic structure using a binder jetting 3D printing method is provided. The method of manufacturing the ceramic structure includes preparing a base powder in which spherical alumina (Al ₂ O ₃ ) powder and a surface modifier are mixed, including water, polyvinyl alcohol (PVA), and glass frit. Preparing a functional binder, manufacturing a ceramic structure using the binder jetting 3D printing method using the base powder and the functional binder, and sintering the ceramic structure may be included.

Description

Method for manufacturing a ceramic structure using a binder jetting 3D printing method, and a ceramic structure manufactured using a binder jetting method 3D printing method}

The present invention relates to a method for manufacturing a ceramic structure using a binder jetting 3D printing method, and a ceramic structure manufactured using a binder jetting 3D printing method.

Ceramic materials such as silica, alumina, and zirconia are actively applied in various fields such as aerospace, medical, eco-friendly, and energy industries due to their excellent physical and chemical properties such as low thermal expansion coefficient and excellent wear resistance and corrosion resistance.

However, due to the unique characteristics of ceramic materials, despite their excellent mechanical, chemical, and thermal properties, they have high hardness and strong brittleness, making them difficult to apply to areas requiring complex shape processing. Demand for complex shape implementation by applying 3D printing technology is increasing in order to overcome the intractability of ceramic materials and improve processability.

3D printing technology is a process technology that manufactures a three-dimensional solid shape by repeatedly stacking desired materials in a two-dimensional section from three-dimensionally designed digital data. It has the advantage of greatly reducing the cost and time of the manufacturing process because it is very free to design or modify the design, consumes less material than the existing cutting process, and eliminates unnecessary manufacturing processes. Various types of 3D printing facilities have been developed according to the layering method, and the demand for the development of new materials for 3D printing corresponding to them is gradually increasing.

Recently, 3D printing technology has been actively researched to apply new materials that exhibit excellent physical and chemical performance, such as ceramics, to 3D printing by combining them with polymers, moving away from existing polymer-oriented materials. Until now, the material industry has focused on developing new materials to meet the high performance demanded by the demand industry. It's getting attention. Types of 3D printing technologies include SLS (Selective laser sintering), FDM (Fused deposition modeling), SLA (Stereo lithography apparatus), Ink-jet, Binder jetting, etc. can be distinguished by

The double binder jetting 3D printing method is a technology first developed in 1993 at the Massachusetts Institute of Technology (MIT) under the name of 'powder bed and inket head 3d printing'. It is a technology to stack sculptures while repeating the process of spraying and hardening one layer, then the bed goes down, applying new powder thinly, and then spraying the binding material again. Compared to existing processes using extrusion, injection, press, etc., this binder jetting 3D printing method has the advantage of being able to easily create complex shapes, having a wide selection of materials, and having a simple process process. However, there is a problem that the strength and resolution of the sintered body are relatively low. Accordingly, various studies are being conducted to solve these problems.

One technical problem to be solved by the present invention is to provide a method for manufacturing a ceramic structure using a binder jetting 3D printing method, and a ceramic structure manufactured using a binder jetting 3D printing method.

Another technical problem to be solved by the present invention is to provide a ceramic structure having improved strength and a manufacturing method thereof.

Another technical problem to be solved by the present invention is to provide a ceramic structure with improved resolution and a manufacturing method thereof.

The technical problem to be solved by the present invention is not limited to the above.

In order to solve the above technical problems, a method of manufacturing a ceramic structure using a binder jetting 3D printing method is provided.

According to one embodiment, the method of manufacturing a ceramic structure using the binder jetting 3D printing method includes preparing a base powder in which spherical alumina (Al ₂ O ₃ ) powder and a surface modifier are mixed, water, PVA (polyvinyl alcohol) and glass frit, preparing a ceramic structure using the binder jetting 3D printing method through the base powder and the functional binder, and sintering the ceramic structure. steps may be included.

According to an embodiment, the manufacturing of the ceramic structure may include controlling the strength of the ceramic structure as a binder saturation level (BSL) for manufacturing the ceramic structure is controlled.

According to an embodiment, as the BSL for manufacturing the ceramic structure is controlled to be more than 100% and less than 150%, the strength of the ceramic structure may be improved.

According to an embodiment, the ceramic sintered body is divided into a plurality of regions, and each of the plurality of regions may include a different BSL.

According to one embodiment, the glass firt may be used in an amount greater than 5 wt% and less than 15 wt% based on the total weight of the functional binder.

According to one embodiment, the surface modifier may include fumed silica and aluminum oxide.

According to one embodiment, the surface modifier may have hydrophilicity.

According to an embodiment, the method of manufacturing a ceramic structure using the binder jetting 3D printing method includes: after the step of manufacturing the ceramic structure and before the step of sintering the ceramic structure, the steps of drying the ceramic structure, and the dried ceramic structure The method may further include removing powders remaining on the surface of and removing PVA remaining in the dried ceramic structure.

According to one embodiment, the step of removing the PVA remaining in the dried ceramic structure may include heat treatment to a temperature of 550 °C at a heating rate of 3 °C/min.

According to one embodiment, the sintering of the ceramic structure may include heat treatment to a temperature of 1400°C to 1600°C at a heating rate of 5°C/min.

In order to solve the above technical problems, a ceramic structure manufactured using a binder jetting 3D printing method is provided.

According to an embodiment, the ceramic structure manufactured using the binder jetting 3D printing method may have a core-shell structure, but the core and the shell may have different binder saturation levels (BSLs). .

According to an embodiment, the BSL of the core may be greater than 50% and less than 100%, and the BSL of the shell may be greater than 100% and less than 150%.

A method for manufacturing a ceramic structure according to an embodiment of the present invention includes preparing base powder in which spherical alumina (Al ₂ O ₃ ) powder and a surface modifier are mixed, water, polyvinyl alcohol (PVA), and glass frit ( It may include preparing a functional binder including glass frit), preparing a ceramic structure using the binder jetting 3D printing method through the base powder and the functional binder, and sintering the ceramic structure. Accordingly, a ceramic structure manufactured by a binder jetting 3D printing method and having improved strength of a sintered body may be provided.

1 and 2 are flowcharts for explaining a method of manufacturing a ceramic structure according to an embodiment of the present invention.
3 is a view for explaining an example of a ceramic structure according to an embodiment of the present invention.
4 is a view for explaining another example of a ceramic structure according to an embodiment of the present invention.
5 is a view for explaining the shape of a ceramic structure according to Experimental Example 1 of the present invention.
6 is a photograph of a ceramic structure according to a comparative example of the present invention sintered at a temperature of 1400 ° C.
7 is a photograph of a ceramic structure according to a comparative example of the present invention sintered at a temperature of 1450 ° C.
8 is a photograph of a ceramic structure according to a comparative example of the present invention sintered at a temperature of 1500 ° C.
9 is a photograph of a ceramic structure according to a comparative example of the present invention sintered at a temperature of 1550 ° C.
10 is a photograph of a ceramic structure according to a comparative example of the present invention sintered at a temperature of 1600 ° C.
11 is a photograph of a ceramic structure according to Experimental Example 1-1 of the present invention.
12 is a photograph of a ceramic structure according to Experimental Examples 1-2 of the present invention.
13 is a photograph of a ceramic structure according to Experimental Examples 1-3 of the present invention.
14 is a photograph of a ceramic structure according to Experimental Examples 1 to 4 of the present invention.
15 is a photograph of a ceramic structure according to Experimental Examples 1 to 5 of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the technical spirit of the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided so that the disclosed content will be thorough and complete, and the spirit of the present invention will be sufficiently conveyed to those skilled in the art.

In this specification, when an element is referred to as being on another element, it means that it may be directly formed on the other element or a third element may be interposed therebetween. Also, in the drawings, the thicknesses of films and regions are exaggerated for effective explanation of technical content.

In addition, although terms such as first, second, and third are used to describe various elements in various embodiments of the present specification, these elements should not be limited by these terms. Therefore, what is referred to as a first element in one embodiment may be referred to as a second element in another embodiment.

Each embodiment described and illustrated herein also includes its complementary embodiments. In addition, in this specification, 'and/or' is used to mean including at least one of the elements listed before and after.

In the specification, expressions in the singular number include plural expressions unless the context clearly dictates otherwise. In addition, the terms "comprise" or "having" are intended to designate that the features, numbers, steps, components, or combinations thereof described in the specification exist, but one or more other features, numbers, steps, or components. It should not be construed as excluding the possibility of the presence or addition of elements or combinations thereof.

In addition, in the following description of the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description will be omitted.

1 and 2 are flowcharts for explaining a method of manufacturing a ceramic structure according to an embodiment of the present invention, FIG. 3 is a view for explaining an example of a ceramic structure according to an embodiment of the present invention, and FIG. It is a drawing for explaining another example of a ceramic structure according to an embodiment of the present invention.

Referring to FIGS. 1 and 2 , base powder may be prepared (S100). According to one embodiment, the base powder may be formed by mixing spherical alumina (Al ₂ O ₃ ) powder and a surface modifier. The surface modifier may improve flowability of the base powder. Accordingly, the 3D printing structure manufactured through the base powder may have improved resolution and strength.

According to one embodiment, the surface modifier includes fumed silica and aluminum oxide, but may have hydrophilicity. In contrast, when a hydrophobic material is used as the surface modifier, a problem in that the binder does not easily penetrate during the 3D printing process may occur. For example, a product of Konasil (k-90) may be used as the surface modifier. Alternatively, for example, Aerosil (200), Aerosil (R-972), aeroxide (ALU C), and the like may be used as the surface modifier. The characteristics of the surface modifiers described above are summarized in <Table 1> and <Table 2> below.

Properties Aerosil (200) Konasil (k-90) Aerosil (R-972) Aeroxide (ALU C) Behavior in water Hydrophilic Hydrophilic Hydrophobic Hydrophobic Mean size/nm 12 7 16 13 Specific surface area m ² /g 200±25 90±15 110±20 100±15 Tamped density g/L 500 50 50 50 Drying loss(2h at 105℃)% < 1.5 ≤ 1.0 ≤ 2.0 ≤ 5.0 Ph-value (4% suspension) 3.6~4.3 3.7~4.7 3.6~4.4 4.5 to 5.5

division Hydrophilic Hydrophobic Aerosil
(200) Konasil
(k-90) Aerosil
(R-972) aeroxide
(ALU C) angle of repose (°) 52.64 37.11 20 46.32 Flowability index Cohensive Free-flowing Very Free-flowing Cohensive Contact angle (°) 37.63 37.40 49.69 60.44 Powder bed surface roughness
(μm) 12.3 5.39 5.08 9.8

A functional binder may be prepared (S200). According to one embodiment, the functional binder may include water (H ₂ O), polyvinyl alcohol (PVA), and glass frit. The glass frit may improve the strength of a ceramic structure to be described later. In contrast, when a ceramic structure is created using a binder without the glass frit, strength of the ceramic structure may be reduced. According to one embodiment, the glass frit may be used in an amount greater than 5 wt% and less than 15 wt% based on the total weight of the functional binder. When the glass frit is included in 5 wt%, 10 wt%, and 15 wt%, the characteristics of the functional binder are summarized through <Table 3> below.

division 5wt% 10wt% 15wt% Viscosity (mPa S) 5.59 6.53 6.81 Density (g/ml) 0.81 1.05 1.1 Surface tension (mN/m) 19.25 21.06 25.04 Volume of one Droplet (Pico liter) 80 80 80 Fluid velocity (m/s) 3 3 3 Oh ^-1 5.16 5.27 5.64

In the above-described <Table 3>, the value of Oh ^-1 (Ohnesorge number) can be calculated through <Equation 1>, <Equation 2>, and <Equation 3> below.

<Equation 1>

(γ: surface tension, ρ: density, v: flow, a: nozzle diameter, η: viscosity, N _We : Weber number, N _Re : Reynolds number)

<Equation 2>

<Equation 3>

A ceramic structure may be manufactured by a binder jetting 3D printing method through the base powder and the functional binder (S300). Thereafter, drying the ceramic structure (S310), removing powders remaining on the surface of the dried ceramic structure (S320), removing PVA remaining on the dried ceramic structure (S330), and Sintering the ceramic structure (S400) may be performed.

More specifically, the ceramic structure manufactured through the base powder and the functional binder is dried in an oven at 80 ° C. for 2 hours, and then the powder remaining on the surface is removed (De-powder) and contained in the binder It may be heat-treated to a temperature of 550 ° C. at a heating rate of 3 ° C. / min in order to de-bind the PVA present thereon. Finally, after being sintered by a heat treatment method to a temperature of 1400 ° C to 1600 ° C at a heating rate of 5 ° C / min, it may be maintained for 5 hours.

According to an embodiment, in the manufacturing of the ceramic structure (S300), the strength of the ceramic structure may be controlled as a binder saturation level (BSL) for manufacturing the ceramic structure is controlled. For example, the BSL for manufacturing the ceramic structure may be controlled to be greater than 100% and less than 150%. Accordingly, the strength of the ceramic structure may be improved.

According to one embodiment, the ceramic structure may be manufactured to form a BSL gradient. For example, as shown in FIG. 3 , the ceramic structure SC is divided into first to fifth regions A ₁ , A ₂ , A ₃ , A ₄ , and A ₅ , and the first to fifth regions SC. The BSLs of the five regions (A ₁ , A ₂ , A ₃ , A ₄ , and A ₅ ) may be manufactured to be different from each other. Specifically, the BSL of the first area A ₁ is 50%, the BSL of the second area A ₂ is 75%, the BSL of the third area A ₃ is 100%, and the BSL of the fourth area ( The ceramic structure may be manufactured such that the BSL of A ₄ ) is 125% and the BSL of the fifth region A ₅ is 150%. As described above, a ceramic structure manufactured to form a gradient of BSL may have improved strength compared to a ceramic structure having a constant BSL. The BSL gradient of the ceramic structure may be formed horizontally at once or formed in a vertical stacked form and then laid down.

In addition, for another example, as shown in FIG. 4, the ceramic structure (SC) has a core-shell structure, but is manufactured so that the BSL of the core (C) and the shell (S) are different from each other. It can be. Specifically, the BSL of the core (C) may be made more than 50% and less than 100%. Alternatively, the BSL of the shell S may be made greater than 100% and less than 150%. As described above, as the BSL of the core C and the shell S is controlled, the strength of the ceramic structure SC may be improved.

In the above, the ceramic structure and method of manufacturing the same according to an embodiment of the present invention have been described. Hereinafter, specific experimental examples and characteristic evaluation results of a ceramic structure and a manufacturing method thereof according to an embodiment of the present invention will be described.

5 is a view for explaining the shape of a ceramic structure according to Experimental Example 1 of the present invention.

Manufacturing of ceramic structure according to Experimental Example 1

Base powder was prepared by mixing spherical alumina (Al ₂ O ₃ ) powder and Konasil (k-90) at 150 rpm for 5 hours using a V-mixer. Water, polyvinyl alcohol (PVA), and glass frit were mixed and stirred to prepare a functional binder.

A ceramic structure having a regular hexahedron shape was manufactured as shown in FIG. 5 by using a binder jetting 3D printing method through a base powder and a functional binder. Specifically, after modeling, it was manufactured under conditions set to a layer thickness of 100 μm, a rotor speed of 60 RPM inside the build chamber, and a constant BSL (Binding Saturation Level).

The prepared ceramic structure was cured by drying in an oven at 80 ° C. for 2 hours, and after removing the powder remaining on the surface, heat treatment was performed to a temperature of 550 ° C. at a heating rate of 3 ° C./min to remove PVA. Finally, after sintering by a method of heat treatment up to a temperature of 1400 ℃ ~ 1600 ℃ at a heating rate of 5 ℃ / min and maintained for 5 hours.

Manufacturing of ceramic structure according to Experimental Example 2

A ceramic structure is manufactured by the method according to Experimental Example 1 described above, but as shown in FIG. 3 , the BSLs of the first to fifth regions A ₁ , A ₂ , A ₃ , A ₄ , and A ₅ are mutually related to each other. Other ceramic structures were fabricated. Specifically, the BSL of the first area A ₁ is 50%, the BSL of the second area A ₂ is 75%, the BSL of the third area A ₃ is 100%, and the BSL of the fourth area A ₄ is 75%. The ceramic structure was manufactured such that the BSL was 125% and the BSL of the fifth region A ₅ was 150%. Further, sintering was performed at a temperature of 1400°C.

Manufacturing of ceramic structure according to Experimental Example 3

A ceramic structure was manufactured by the method according to Experimental Example 1 described above, but as shown in FIG. 4, a ceramic structure having a core-shell structure was manufactured.

Manufacturing a ceramic structure according to a comparative example

A ceramic structure was manufactured by the method according to Experimental Example 1 described above, but glass frit was not used in the process of manufacturing a functional binder. Also, BSL was made at 100%.

6 is a photograph of a ceramic structure according to a comparative example of the present invention sintered at a temperature of 1400 ° C, and FIG. 7 is a photograph of a ceramic structure according to a comparative example of the present invention sintered at a temperature of 1450 ° C, 8 is a photograph of a ceramic structure according to a comparative example of the present invention sintered at a temperature of 1500 ° C, and FIG. 9 is a photograph of a ceramic structure according to a comparative example of the present invention sintered at a temperature of 1550 ° C, 10 is a photograph of a ceramic structure according to a comparative example of the present invention sintered at a temperature of 1600 ° C.

6 to 10, SEM (Scanning Electron Microscope) photographs are shown of ceramic structures according to the comparative examples sintered at different temperatures (1400 ° C, 1450 ° C, 1500 ° C, 1550 ° C, 1600 ° C). In addition, The characteristics of the ceramic structures manufactured under each condition were measured, and the measured results are summarized in <Table 4> below.

division 1400℃ 1450℃ 1500℃ 1550℃ 1600℃ Porosity (%) 67.6 66.6 64.7 63.3 60.6 Average pore size (μm) 8.5 8.4 8.1 8.1 7.4 Surface roughness (μm) 15.5 14.3 13.2 12.8 12.3 density (%) 38.7 39.2 40.5 43.2 47.0 Sintered body strength (MPa) 2.32 2.33 3.52 4.68 4.89

Manufacturing a ceramic structure according to Experimental Example 1-1

A ceramic structure was manufactured by the method according to Experimental Example 1 described above, but at a 50% BSL condition and a sintering temperature of 1400°C.

Manufacturing a ceramic structure according to Experimental Example 1-2

A ceramic structure was manufactured by the method according to Experimental Example 1 described above, but at a sintering temperature of 1400° C. under conditions of 75% BSL.

Manufacturing of ceramic structures according to Experimental Examples 1-3

A ceramic structure was manufactured by the method according to Experimental Example 1 described above, but at a 100% BSL condition and a sintering temperature of 1400°C.

Manufacturing of ceramic structures according to Experimental Examples 1-4

A ceramic structure was manufactured by the method according to Experimental Example 1 described above, but at a BSL 125% condition and a sintering temperature of 1400°C.

Manufacturing of ceramic structures according to Experimental Examples 1-5

A ceramic structure was manufactured by the method according to Experimental Example 1 described above, but under the condition of 150% BSL.

11 is a photograph of a ceramic structure according to Experimental Example 1-1 of the present invention, FIG. 12 is a photograph of a ceramic structure according to Experimental Example 1-2 of the present invention, and FIG. 13 is an experimental example of the present invention. 1-3 is a photograph of a ceramic structure, FIG. 14 is a photograph of a ceramic structure according to Experimental Example 1-4 of the present invention, and FIG. 15 is a photograph of a ceramic structure according to Experimental Example 1-5 of the present invention. this is a picture taken

Referring to FIGS. 11 to 15 , the ceramic structures according to Experimental Examples 1-1 to 1-5 are photographed using a scanning electron microscope (SEM). 11 to 15, it can be seen that the ceramic structures according to Experimental Examples 1-1 to 1-5 have a porous structure.

In addition, the characteristics of the ceramic structures according to Experimental Examples 1-1 to 1-5 and the ceramic structures according to Experimental Example 2 were measured. The measured results are summarized in <Table 5> below.

division Experiment example
1-1 Experiment example
1-2 Experiment example
1-3 Experiment example
1-4 Experiment example
1-5 Experiment example
2 Porosity (%) 63.6 61.9 60.8 58.7 58.1 62.4 Average pore size (μm) 10.1 9.8 9.5 9.4 9.5 9.7 Surface roughness (μm) 12.5 12.0 11.8 10.9 12.1 10.6 density(%) 40.1 40.7 43.9 50.2 49.1 46.1 Sintered body strength (MPa) 9.17 9.98 13.25 23.30 18.36 26.10

As can be seen in <Table 4> and <Table 5>, although the ceramic structures according to Experimental Examples 1-3 and Comparative Example were manufactured under the same conditions (100% BSL, sintering temperature 1400 ° C), glass frit ), it was confirmed that a significant difference in the strength of the sintered body occurred with or without use.

Specifically, it can be confirmed that the ceramic structure according to the Comparative Example in which the glass frit is not used has a sintered strength of 2.32 MPa, but the ceramic structure according to Experimental Examples 1-3 in which the glass frit is used has a sintered strength of 13.25 MPa. could Accordingly, it can be seen that the strength of the sintered body can be remarkably improved by using the glass frit.

In addition, as a result of comparing the strength of the sintered body of the ceramic structures according to Experimental Examples 1-1 to 1-5, as the BSL increased to 50% to 125% (Experimental Example 1-1 to Experimental Example 1-4), the sintered body It was confirmed that the strength continuously increased from 9.17 MPa to 23.30 MPa. However, it was confirmed that the strength of the sintered body decreased from 23.30 MPa to 18.36 MPa as the BSL increased to 125% to 150% (Experimental Example 1-4 to Experimental Example 1-5). That is, it was confirmed that the strength of the sintered body had a maximum value at 125% BSL, and the lower and upper limits were 100% and 150%, respectively.

As a result, it can be seen that in the case of manufacturing a ceramic structure with a constant BSL, the strength of the finally manufactured ceramic structure can be improved by controlling the BSL to greater than 100% and less than 150%.

In addition, in the case of the ceramic structure according to Experimental Example 2, it was confirmed that the sintered body strength (26.10 MPa) was higher than that of Experimental Examples 1-1 to 1-5. That is, it was confirmed that the strength of the ceramic structure having a BSL gradient was higher than that of the ceramic structure having a constant BSL.

Manufacturing a ceramic structure according to Experimental Example 3-1

A ceramic structure was manufactured by the method according to Experimental Example 3 described above, but the BSL of the shell (S) was manufactured with 50% and the BSL of the core (C) was manufactured with 150%.

Manufacturing a ceramic structure according to Experimental Example 3-2

A ceramic structure was manufactured by the method according to Experimental Example 3 described above, but the BSL of the shell (S) was manufactured with 75% and the BSL of the core (C) was manufactured with 125%.

Manufacturing a ceramic structure according to Experimental Example 3-3

A ceramic structure was manufactured by the method according to Experimental Example 3 described above, but the BSL of the shell (S) was manufactured with 100% and the BSL of the core (C) was manufactured with 100%.

Manufacturing of ceramic structures according to Experimental Examples 3-4

A ceramic structure was manufactured by the method according to Experimental Example 3 described above, but the BSL of the shell (S) was manufactured with 125% and the BSL of the core (C) was manufactured with 75%.

Manufacturing of ceramic structures according to Experimental Examples 3-5

A ceramic structure was manufactured by the method according to Experimental Example 3 described above, but the BSL of the shell (S) was manufactured with 150% and the BSL of the core (C) was manufactured with 50%.

Ceramic structures according to Experimental Examples 3-1 to 3-5 described above are summarized in <Table 6> below. In addition, the characteristics of each of the ceramic structures according to Experimental Examples 3-1 to 3-5 were measured, and the measured results are summarized in <Table 7> below.

division shell BSL core BSL Experimental Example 3-1 50% 150% Experimental Example 3-2 75% 125% Experimental Example 3-3 100% 100% Experimental Example 3-4 125% 75% Experimental Example 3-5 150% 50%

division Experiment example
3-1 Experiment example
3-2 Experiment example
3-3 Experiment example
3-4 Experiment example
3-5 Porosity (%) 58.4 59.8 60.8 60.8 61.2 Average pore size (μm) 9.3 9.4 9.5 9.4 9.6 Surface roughness (μm) 11.2 11.5 11.8 11.6 12.0 density(%) 46.3 45.5 43.9 43.8 43.5 Sintered body strength (MPa) 10.11 13.89 15.25 20.93 17.31

As can be seen in <Table 6> and <Table 7>, as a result of comparing the sintered strength of the ceramic structures according to Experimental Examples 3-1 to 3-5, the BSL of the shell increased to 50% to 125%, and the core As the BSL decreased from 150% to 75% (Experimental Example 3-1 to Experimental Example 3-4), it was confirmed that the strength of the sintered body continuously increased from 10.11 MPa to 20.93 MPa. However, as the BSL of the shell increased from 125% to 150% and the BSL of the core decreased from 75% to 50% (Experimental Example 3-4 to Experimental Example 3-5), the strength of the sintered body increased from 20.93 MPa to 17.31 MPa. A decrease was observed.

That is, it can be confirmed that the strength of the sintered body has a maximum value at 125% of shell BSL and 75% of core BSL, a lower limit at 100% of shell BSL and 50% of core BSL, and an upper limit at 150% of shell BSL and 100% of core BSL. could As a result, when a core-shell structured ceramic structure is manufactured, the BSL of the core is controlled to be greater than 50% and less than 100%, and the BSL of the shell is controlled to be greater than 100% and less than 150%, so that the strength of the finally manufactured ceramic structure is controlled. can be improved.

In the above, the present invention has been described in detail using preferred embodiments, but the scope of the present invention is not limited to specific embodiments, and should be interpreted according to the appended claims. In addition, those skilled in the art should understand that many modifications and variations are possible without departing from the scope of the present invention.

SC: ceramic structure
A ₁ to A ₅ : first to fifth regions
C: core
S: shell

Claims (12)

In the method of manufacturing a ceramic structure using a binder jetting 3D printing method,
Preparing a base powder in which spherical alumina (Al ₂ O ₃ ) powder and a surface modifier are mixed;
preparing a functional binder including water, polyvinyl alcohol (PVA), and glass frit;
manufacturing a ceramic structure by a binder jetting 3D printing method through the base powder and the functional binder; and
A method of manufacturing a ceramic structure using a binder jetting 3D printing method comprising the step of sintering the ceramic structure.
According to claim 1,
A method of manufacturing a ceramic structure using a binder jetting 3D printing method, comprising controlling the strength of the ceramic structure as a binder saturation level (BSL) for manufacturing the ceramic structure is controlled in the manufacturing of the ceramic structure. .
According to claim 2,
Method for manufacturing a ceramic structure using a binder jetting 3D printing method, comprising improving the strength of the ceramic structure as the BSL for manufacturing the ceramic structure is controlled to more than 100% and less than 150%.
According to claim 1,
The ceramic sintered body is divided into a plurality of regions, and the BSL of each of the plurality of regions includes a different one, a method of manufacturing a ceramic structure using a binder jetting 3D printing method.
According to claim 1,
The method of manufacturing a ceramic structure using a binder jetting 3D printing method, comprising using the glass firt in an amount of more than 5 wt% and less than 15 wt% based on the total weight of the functional binder.
According to claim 1,
The method of manufacturing a ceramic structure using a binder jetting 3D printing method, wherein the surface modifier includes fumed silica and aluminum oxide.
According to claim 6,
The surface modifier has a hydrophilic property, a method of manufacturing a ceramic structure using a binder jetting 3D printing method.
According to claim 1,
After the step of manufacturing the ceramic structure and before the step of sintering the ceramic structure,
drying the ceramic structure;
removing powders remaining on the dried surface of the ceramic structure; and
Method for manufacturing a ceramic structure using a binder jetting 3D printing method, further comprising removing PVA remaining in the dried ceramic structure.
According to claim 8,
The step of removing the PVA remaining in the dried ceramic structure includes heat treatment up to a temperature of 550 ℃ at a heating rate of 3 ℃ / min, a method for manufacturing a ceramic structure using a binder jetting 3D method.
According to claim 1,
The step of sintering the ceramic structure includes heat treatment to a temperature of 1400 ℃ ~ 1600 ℃ at a heating rate of 5 ℃ / min, a method of manufacturing a ceramic structure using a binder jetting 3D method.
In the ceramic structure manufactured using the binder jetting 3D printing method,
The ceramic structure has a core-shell structure, but the core and the shell have different BSL (Binder Saturation Levels), a ceramic structure manufactured using a binder jetting 3D printing method.
According to claim 11,
A ceramic structure manufactured using a binder jetting 3D printing method, including a BSL of more than 50% and less than 100% of the core and a BSL of more than 100% and less than 150% of the shell.

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