KR102414881B1 - Ceramic paste for light sintering and light sintering method of ceramics - Google Patents

Abstract

Preparing a ceramic paste comprising ceramic particles and an additive having a lower melting point than the ceramic particles, providing the ceramic paste on a substrate, and irradiating light energy to the ceramic paste to melt the additive, There is provided a method of optically sintering a ceramic, comprising the step of permeating a molten additive between the adjacent ceramic particles, thereby photo-sintering the adjacent ceramic particles by heat transferred from the molten and infiltrated additive.

Description

Ceramic paste for light sintering and light sintering method of ceramics

The present invention relates to a ceramic paste for optical sintering and a method for optical sintering of a ceramic, and more particularly, to a ceramic paste for optical sintering that is sintered at a lower temperature and in a shorter time than the conventional sintering method, and a method for optical sintering of the ceramic.

In the sintering of ceramics, heat treatment at high temperature for a long time is required due to the characteristics of the ceramic material. Accordingly, conventionally, in order to sinter the ceramic, a method of heat treatment at a high temperature exceeding about 1400° C. for a long time is used.

However, for high-temperature and long-time heat treatment processes, heat treatment equipment having a complicated structure is required, and there are disadvantages in that high cost is induced. For example, the rapid thermal annealing (RTA) process, which rapidly raises the temperature within a short time, was introduced to solve this problem, but the overall process time becomes longer as a long cooling time is required despite the relatively fast temperature increase time high cost is induced.

Accordingly, there is a need for a method for sintering ceramics in a low temperature and short time process.

One technical problem to be solved by the present invention is to provide a method for optical sintering of a ceramic in which the ceramic is sintered at a low temperature and a short time process.

Another technical problem to be solved by the present invention is to provide a method for optical sintering of ceramics in which ceramic particles are aggregated into a dense structure.

Another technical problem to be solved by the present invention is to provide a method for optical sintering of ceramics that minimizes deformation of physical properties of a ceramic sintered body formed by sintering ceramic particles.

Another technical problem to be solved by the present invention is to provide a ceramic paste for optical sintering that can be sintered at a low temperature and a short time process.

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

In order to solve the above technical problem, the present invention provides a method for optical sintering of ceramics.

According to an embodiment, the photo-sintering method of the ceramic includes the steps of: preparing a ceramic paste including ceramic particles and an additive having a melting point lower than that of the ceramic particles, providing the ceramic paste on a substrate, and the ceramic It includes the steps of melting the additive by irradiating light energy to the paste, penetrating the molten additive between the adjacent ceramic particles, and photo-sintering the adjacent ceramic particles by heat transferred from the melted and permeated additive. can do.

According to an embodiment, the photo-sintering method of the ceramic includes the steps of preparing a ceramic paste including ceramic particles, providing the ceramic paste on a substrate to form a ceramic particle layer including the ceramic particles, and the ceramic Forming an additive layer separate from the ceramic particle layer by providing an additive having a lower melting point than the ceramic particle on the particle layer, and irradiating light energy to the additive layer to melt the additive, The method may include photo-sintering the adjacent ceramic particles by penetrating between the adjacent ceramic particles of the ceramic particle layer to improve mass transfer and heat transfer due to the melted and penetrated additive.

According to an embodiment, the ceramic paste further includes an organic material, and before the photo-sintering, the method further includes preheating the substrate, and the organic material is volatilized by preheating the substrate. can

According to an embodiment, the temperature at which the substrate is preheated may be lower than the melting point of the additive.

According to an embodiment, the optical sintering may include forming a necking between the adjacent ceramic particles by heat transfer and improvement of mass transfer due to the molten and infiltrated additive, and the necking is formed. It may include the step of aggregating adjacent ceramic particles to grow the ceramic particles.

According to an embodiment, the step of growing the ceramic particles may include volatilizing the additive.

According to an embodiment, the optical sintering may include irradiating light energy of more than 90 J/cm ² and less than 110 J/cm ² .

According to an embodiment, the step of sintering the light includes irradiating the light energy in a plurality of sets, and includes irradiating the light energy as a plurality of pulses in the set, An interval between pulses within the set may be less than an interval between the sets.

According to an embodiment, the additive may include at least one selected from the group consisting of Li ₂ O ₃ , Bi ₂ O ₃ , CuO, and NiO.

According to an embodiment, the ceramic particles may include at least one selected from the group consisting of perovskite or metal oxide.

In order to solve the above technical problem, the present invention provides a ceramic paste for optical sintering.

According to an embodiment, the ceramic paste for optical sintering includes ceramic particles and an additive having a melting point lower than that of the ceramic particles, wherein the additive generates heat generated by melting by light energy irradiated to the additive. It can be transferred to ceramic particles.

According to an embodiment, the additive may include at least one selected from the group consisting of Li ₂ O ₃ , Bi ₂ O ₃ , CuO, and NiO.

According to an embodiment, the ceramic particles may include at least one selected from the group consisting of perovskite or metal oxide.

According to a first embodiment of the present invention, preparing a ceramic paste including ceramic particles and an additive having a lower melting point than the ceramic particles, providing the ceramic paste on a substrate, and light energy to the ceramic paste irradiating to melt the additive, and permeating the molten additive between the adjacent ceramic particles, thereby photo-sintering the adjacent ceramic particles by improved mass transfer and heat transfer from the molten and infiltrated additive. A method for optical sintering of ceramics may be provided.

Further, according to a second embodiment of the present invention, preparing a ceramic paste including ceramic particles, providing the ceramic paste on a substrate to form a ceramic particle layer including the ceramic particles, on the ceramic particle layer providing an additive having a lower melting point than the ceramic particles to form an additive layer separate from the ceramic particle layer, and irradiating light energy to the additive layer to melt the additive, There may be provided a method for photo-sintering ceramics, comprising the step of penetrating between the adjacent ceramic particles of a particle layer, and photo-sintering the adjacent ceramic particles by heat transferred from the melted and penetrated additive.

Accordingly, according to the embodiments of the present invention, it is possible to sinter the ceramic at a low temperature and for a short time, so that it is possible to simplify the sintering equipment and reduce the process cost, so it is economical. Furthermore, due to the above-mentioned advantages of economy, mass production is possible, so industrial competitiveness can be secured.

In addition, according to embodiments of the present invention, by gradually increasing the light energy intensity, it is possible to minimize a sudden temperature rise that may be caused to the ceramic sintered body formed by sintering the ceramic particles and the substrate. Accordingly, deformation or damage to physical properties of the ceramic sintered body and the substrate may be minimized.

The optical sintering method of ceramics according to embodiments of the present invention may be applied to various fields requiring a ceramic sintering process, for example, various ceramics fields, fuel cells, secondary batteries, and the like.

1 is a flowchart illustrating a method of optically sintering a ceramic according to a first embodiment of the present invention.
2 is a flowchart illustrating a method for optically sintering a ceramic according to a second embodiment of the present invention.
3 is a view for explaining the optical sintering step of the present invention.
4 is a diagram for explaining step S230 of the present invention.
5 is a graph illustrating a method of irradiating light energy according to Experimental Example 1 of the present invention.
6 is a photograph of a ceramic sintered body according to Experimental Example 1-1 of the present invention.
7 is a photograph of a ceramic sintered body according to Experimental Example 1-2 of the present invention.
8 is a photograph of a ceramic sintered body according to Experimental Examples 1-3 of the present invention.
9 is a photograph of a ceramic sintered body according to Experimental Examples 1-4 of the present invention.
10 is a photograph of a ceramic sintered body according to Experimental Examples 1-5 of the present invention.
11 is a graph illustrating a method of irradiating light energy according to Experimental Example 2 of the present invention.
12 is a photograph of a ceramic sintered body according to Experimental Example 2 of the present invention.
13 is a photograph of ceramic particles according to Comparative Example 1.
14 is a photograph of a ceramic sintered body according to Comparative Example 2.
15 is a photograph of a ceramic sintered body according to Comparative Example 3.

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 may be thorough and complete, and the spirit of the present invention may be sufficiently conveyed to those skilled in the art.

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

In addition, in various embodiments of the present specification, terms such as first, second, third, etc. are used to describe various components, but these components should not be limited by these terms. These terms are only used to distinguish one component from another. Accordingly, what is referred to as a first component in one embodiment may be referred to as a second component in another embodiment. Each embodiment described and illustrated herein also includes a complementary embodiment thereof. In addition, in this specification, 'and/or' is used in the sense of including at least one of the components listed before and after.

In the specification, the singular expression includes the plural expression unless the context clearly dictates otherwise. In addition, terms such as "comprise" or "have" are intended to designate that a feature, number, step, element, or a combination thereof described in the specification exists, but one or more other features, number, step, configuration It should not be construed as excluding the possibility of the presence or addition of elements or combinations thereof. In addition, in this specification, "connection" is used in a sense including both indirectly connecting a plurality of components and directly connecting a plurality of components.

In addition, terms such as “…unit”, “…group”, and “module” described in the specification mean a unit that processes at least one function or operation, which may be implemented as hardware or software or a combination of hardware and software. have.

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

1 is a flowchart illustrating a method of optically sintering a ceramic according to a first embodiment of the present invention, FIG. 2 is a flowchart illustrating a method of optically sintering a ceramic according to a second embodiment of the present invention, and FIG. It is a view for explaining the step of sintering the light of the present invention, Figure 4 is a view for explaining the step S230 of the present invention.

Referring to FIG. 1 , the photo-sintering method of a ceramic according to a first embodiment of the present invention includes the steps of preparing a ceramic paste including ceramic particles ( S110 ), and providing the ceramic paste on a substrate ( S120 ). , preheating the substrate (S130), and optically sintering the ceramic particles (S140) may include at least one.

Hereinafter, each step S110 to S140 will be described in more detail.

Step S110

In step S110, a ceramic paste may be prepared.

Specifically, according to the first embodiment of the present invention, the ceramic paste may include the ceramic particles 100 and the additive 200 .

Here, the ceramic paste may be understood as a concept including a ceramic ink or a ceramic slurry prepared through a powder process-based non-vacuum process.

According to an embodiment, the additive 200 may have a lower melting point than the ceramic particle 100 . That is, the additive 200 may be melted and liquefied before the ceramic particles 100 by heat treatment.

The additive 200 may be, for example, at least one selected from the group consisting of Li ₂ O ₃ , Bi ₂ O ₃ , CuO, and NiO.

In addition, the ceramic particles 100 may be at least one selected from the group including perovskite or metal oxide, for example, YSZ ((Yttria-stabilized zirconia).

Step S120

In step S120, the ceramic paste may be provided on the substrate.

Accordingly, on the substrate, it is possible to form a ceramic 100-additive 200 composite layer including the ceramic particles 100 and the additive 200 .

According to an embodiment, the substrate may be a composite of a metal and a ceramic, for example, at least one selected from the group consisting of Ni-YSZ.

Step S130

In step S130, the substrate may be preheated.

According to an embodiment, since the ceramic paste may further include an organic material, the organic material included in the ceramic paste may be volatilized through the preliminary heating.

Accordingly, when the ceramic particles 100 are sintered in a step to be described later, a pure ceramic sintered body 100S in which the organic material is volatilized may be obtained from the ceramic paste.

Furthermore, the ceramic sintered body 100S formed by sintering the substrate and the ceramic particles 100 while volatilizing the organic material included in the ceramic paste by performing the preliminary heating at a relatively lower temperature than the optical sintering step to be described later. ), it is possible to minimize the physical property deformation of the substrate and the ceramic sintered body 100S by minimizing the sudden temperature rise that may be induced.

According to an embodiment, the preheating temperature of the substrate may be lower than the melting point of the additive 200 . For example, when the additive 200 is Bi ₂ O ₃ (melting point 890 ℃), the preheating temperature may be 300 ~ 600 ℃.

Accordingly, by preheating the substrate, the additive 200 may not be melted while the organic material included in the ceramic paste is volatilized.

According to an embodiment, the substrate may be heated through the preheating in step S130, as well as in the process in which light energy LE1 is irradiated so that the ceramic particles 100 are sintered in the optical sintering step to be described later. can be heated.

Step S140

In step S140 , the ceramic particles 100 may be photo-sintered.

Specifically, light energy LE1 (refer to FIG. 3 ) may be irradiated to the ceramic paste including the ceramic particles 100 and the additive 200 , so that the ceramic particles 100 may be photo-sintered.

More specifically, referring to FIG. 3 , light energy LE1 may be irradiated from the light source LS to the ceramic paste including the ceramic particles 100 and the additive 200 .

In this case, the light source LS may be extreme-wave white light, and as illustrated in FIG. 5 , the light energy LE1 may be irradiated with a plurality of pulses as one set.

In this case, as shown in FIG. 5 , the light energy LE1 may be irradiated so that the interval IV1_off between pulses to which the light energy is not irradiated is larger than the interval IV1_on to which the light energy is irradiated as a pulse. have

In this case, the extreme-wave white light may be irradiated for, for example, 0.01 to 50 ms.

Alternatively, the extreme-wave white light may be irradiated with a pulse interval of, for example, 0.01 to 5000 ms.

Alternatively, the extreme wave white light may be irradiated with, for example, 1 to 100 pulses.

According to an embodiment, as shown in FIG. 11 , the light energy LE1 is irradiated with a plurality of pulses as one set, and the set may be irradiated a plurality of times. In this case, it may be irradiated such that the interval IV2 between the sets is greater than the interval IV1 between the pulses in the set.

According to an embodiment, in step S140 , the additive 200 in the ceramic paste may be melted (200M) by the light energy LE1 irradiated from the light source LS (see FIG. 3(A) ). )). As shown in FIG. 3A , the molten additive 200M may penetrate between the adjacent ceramic particles 100 .

That is, as the additive 200 is melted 200M by the light energy LE1, fluidity of the melted additive 200M may be improved, and the adjacent ceramic particles 100 may permeate through gaps. there will be

Accordingly, the molten additive 200M may form a wider contact surface with the ceramic particles 100 than before melting.

According to an embodiment, the melted additive 200M penetrating between the ceramic particles 100 may transfer heat generated by melting by the light energy LE1 irradiation to the ceramic particles 100 . .

Accordingly, the adjacent ceramic particles 100 may be sintered by the heat.

In addition, as described above, the molten additive 200M can form a wider contact surface with the ceramic particles 100 than before melting, and the ceramic particles 100 from the irradiated light energy LE1 ) and can transfer the heat to a wider contact surface formed with them.

Accordingly, according to an embodiment of the present invention, the sintering characteristics between the adjacent ceramic particles 100 may be improved.

Looking more specifically with reference to the drawings, as shown in FIG. 3A , the ceramic particles 100 may receive heat from the molten additive 200M, and the adjacent ceramic particles 100 . A necking (100N) may be formed between them.

Thereafter, as shown in FIG. 3B , the adjacent ceramic particles 100 on which the necking 100N is formed are aggregated, so that the ceramic particles may be grown 100G.

In this case, the molten additive 200M may be volatilized after transferring the heat so that the ceramic particles 100 are grown. That is, the molten additive 200M is volatilized after transferring the heat to the ceramic particles 100 , and as shown in FIG. 3C , a ceramic sintered body including only the pure ceramic particles 100 . (100S) can be obtained.

In addition, as described above in step S130, the organic material included in the ceramic paste may be volatilized, and in step S140, the additive 200 may be volatilized, thereby obtaining the pure ceramic sintered body 100S. .

According to an embodiment, the light energy LE1 in step S140 may be irradiated in a range of 95 to 100 J/cm ² .

Or, according to an embodiment, as shown in FIG. 11 in step S140, the light energy intensity irradiated in the set following the preceding set includes the irradiated with a plurality of pulses as one set. can be large

Accordingly, the structure of the ceramic sintered body 100S formed by sintering the ceramic particles 100 may be densely formed.

Furthermore, as described above, as the light energy intensity is gradually increased so that the light energy intensity irradiated from the set following the preceding set is greater than that of the preceding set, a sudden temperature rise that may be induced in the ceramic sintered body 100S and the substrate By minimizing , deformation or damage to physical properties of the ceramic sintered body 100S and the substrate may be minimized.

In addition, as described above in step S130, the substrate may be heated not only through the preliminary heating, but also during the process in which the light energy LE1 is irradiated so that the ceramic particles 100 are sintered.

Accordingly, it is of course possible to minimize physical property deformation or damage to the ceramic sintered body 100S and the substrate by minimizing a sudden temperature rise that may be caused to the ceramic sintered body 100S and the substrate.

Hereinafter, a method of optically sintering a ceramic according to a second embodiment of the present invention will be described. In the second embodiment of the present invention to be described below, descriptions overlapping those of the first embodiment of the present invention described above will be omitted. For example, the ceramic particles or additives described above in the first embodiment of the present invention and the ceramic particles or additives of the second embodiment of the present invention to be described later may be the same material, and therefore, a description of each material may be omitted. there will be

Referring to FIG. 2 , in the optical sintering method of a ceramic according to a second embodiment of the present invention, a step of preparing a ceramic paste including ceramic particles ( S210 ), and providing the ceramic paste on a substrate to form a ceramic particle layer (S220), forming an additive layer separate from the ceramic particle layer on the ceramic particle layer (S230), preheating the substrate (S240), and photo-sintering the ceramic particles (S250) ) may include at least one of.

Hereinafter, each step S210 to S250 will be described in more detail.

Step S210

In step S210, a ceramic paste may be prepared.

Specifically, in the second embodiment of the present invention, the ceramic paste may not include the additive 200 , unlike the first embodiment of the present invention described above.

That is, according to the second embodiment of the present invention, the ceramic paste may be made of the ceramic particles 100 and the organic material.

Step S220

In step S220 , the ceramic paste may be provided on a substrate to form a ceramic particle layer including the ceramic particles 100 .

That is, in the first embodiment of the present invention described above, the ceramic 100-additive 200 composite layer is formed on the substrate in step S120, while in the second embodiment of the present invention, the substrate in step S220 After the ceramic particle layer is first formed on the ceramic particle layer, an additive layer including the additive 200 may be separately formed on the ceramic particle layer in a step to be described later.

Step S230

In step S230 , as shown in FIG. 4 , an additive layer 200L including the additive 200 separately from the ceramic particle layer 100L on the ceramic particle layer 100L including the ceramic particles 100 . ) can be formed.

Specifically, as described above, the additive 200 constituting the additive layer 200L may have a lower melting point than the ceramic particle 100 .

That is, by providing the additive 200 having a lower melting point than the ceramic particle 100 on the ceramic particle layer 100L, the additive layer 200L separate from the ceramic particle layer 100L can be formed. will be.

Step S240

In step S240, the substrate may be preheated.

As described above in step S130 of the first embodiment of the present invention, the ceramic paste may further include an organic material, and through the preliminary heating, the organic material included in the ceramic paste may be volatilized.

Accordingly, when the ceramic particles 100 are sintered in the step to be described later, it is of course possible to obtain a pure ceramic sintered body 100S in which the organic material is volatilized from the ceramic paste, and further, a step of optical sintering to be described later By performing the preliminary heating at a relatively lower temperature, a rapid temperature rise that may be induced in the ceramic sintered body 100S formed by sintering the substrate and the ceramic particles 100 while volatilizing the organic material included in the ceramic paste Of course, by minimizing , deformation of physical properties of the substrate and the ceramic sintered body 100S can be minimized.

Step S250

In step S250, the ceramic particles 100 may be photo-sintered.

Specifically, light energy LE1 may be irradiated to the additive layer 200L, so that the ceramic particles 100 of the ceramic particle layer 100L may be photo-sintered.

More specifically, in a structure in which the substrate, the ceramic particle layer 100L, and the additive layer 200L are sequentially stacked, light energy LE1 can be irradiated from the light source LS to the additive layer 200L. and the additive 200 of the additive layer 200L may be melted 200M by the light energy LE1.

The molten additive 200M may permeate into the ceramic particle layer 100L adjacent to the additive layer 200L. More specifically, the molten additive 200M may permeate between the adjacent ceramic particles 100 of the ceramic particle layer 100L, as shown in FIG. 3A .

That is, as described above through step S140, the additive 200 is melted 200M by the light energy LE1, so that the molten additive 200M can have improved fluidity, and the adjacent ceramic Particles 100 can be penetrated intermittently.

Accordingly, the molten additive 200M may form a wider contact surface with the ceramic particles 100 than before melting, and sintering characteristics between the adjacent ceramic particles 100 may be improved.

As described above, the melted additive 200M penetrating between the ceramic particles 100 may transfer heat generated by melting by the light energy LE1 irradiation to the ceramic particles 100 .

Accordingly, the adjacent ceramic particles 100 may be sintered by the heat.

At this time, as described above through step S140, the necking 100N may be formed by receiving heat from the molten additive 200M between the adjacent ceramic particles 100, of course (FIG. A) see).

In addition, as the adjacent ceramic particles 100 on which the necking 100N is formed are aggregated, the ceramic particles are grown 100G (refer to FIG. 3B ), and the molten additive 200M is the ceramic particles ( Of course, by volatilizing after transferring the heat to 100), the ceramic sintered body 100S including only the pure ceramic particles 100 can be obtained (see (C) of FIG. 3).

At this time, as shown in FIG. 5 , the light energy LE1 may be irradiated with a plurality of pulses as one set, or the light energy LE1 is shown in FIG. 11 . As described above, a plurality of pulses are irradiated as one set, and when the set is irradiated a plurality of times, the interval IV2 between the sets is greater than the interval IV1 between the pulses in the set. may be investigated.

In addition, as shown in FIG. 11 , the light energy LE1 may be irradiated so that the intensity of light energy is greater in the following set than in the preceding set.

Accordingly, the structure of the ceramic sintered body 100S formed by sintering the ceramic particles 100 may be densely formed.

Furthermore, as described above, as the light energy intensity is gradually increased so that the light energy intensity irradiated from the set following the preceding set is greater than that of the preceding set, a sudden temperature rise that may be induced in the ceramic sintered body 100S and the substrate Of course, by minimizing , deformation or damage to physical properties of the ceramic sintered body 100S and the substrate can be minimized.

Meanwhile, according to the second embodiment of the present invention, by sequentially stacking the substrate, the ceramic particle layer 100L, and the additive layer 200L, the additive melted by the light energy LE1 irradiation ( 200M), in the process of transferring the heat to the ceramic particles 100 of the ceramic particle layer 100L and then volatilizing, the formation of pores in the ceramic particle layer 100L may be minimized.

In other words, through the formation of the additive layer 200L on the ceramic particle layer 100L, even when the molten additive 200M permeated between the ceramic particles 100 is volatilized from the ceramic particle layer 100L. , the formation of pores in the ceramic particle layer 100L can be minimized.

Hereinafter, an experimental example of the present invention will be described.

5 is a graph showing a method of irradiating light energy according to Experimental Example 1 of the present invention, FIG. 6 is a photograph of a ceramic sintered body according to Experimental Example 1-1 of the present invention, and FIG. 7 is an experiment of the present invention A photograph of the ceramic sintered body according to Example 1-2, FIG. 8 is a photograph of the ceramic sintered body according to Experimental Example 1-3 of the present invention, and FIG. 9 is a ceramic sintered body according to Experimental Example 1-4 of the present invention It is a photograph, and FIG. 10 is a photograph of a ceramic sintered body according to Experimental Examples 1-5 of the present invention.

According to Experimental Example 1 of the present invention, as shown in FIG. 5 , in the optical sintering step, light energy LE1 may be irradiated as one set of six pulses.

In addition, according to Experimental Example 1 of the present invention, as shown in FIG. 5 , in the optical sintering step, between the pulses to which the optical energy is not irradiated than the interval IV1_on to which the optical energy LE1 is irradiated as a pulse. The interval IV1_off may be irradiated to be larger.

In this case, the intensity of the irradiated light energy LE1 may be summarized as shown in Table 1 below.

light energy intensity Experimental Example 1-1 80 J Experimental Example 1-2 90 J Experimental Example 1-3 95 J Experimental Example 1-4 100 J Experimental Example 1-5 110 J

6 and 7 , in the ceramic sintered body according to Experimental Examples 1-1 and 1-2, the intensity of light energy LE1 irradiated in the optical sintering step is low, and the adjacent ceramic particles 100 are agglomerated. It can be seen that the size of the grown ceramic particles 100G is small.

Meanwhile, referring to FIGS. 8 and 9 , in the ceramic sintered body according to Experimental Examples 1-3 and 1-4, the adjacent ceramic particles ( 100) are aggregated, and it can be seen that the ceramic particles are grown (100G).

However, referring to FIG. 10 , in the ceramic sintered body according to Experimental Example 1-5, the intensity of the light energy LE1 irradiated in the optical sintering step is too high, and deformation occurs in the aggregated and grown ceramic particles 100G. Alternatively, it can be confirmed that deformation has occurred in the substrate.

Accordingly, through Experimental Example 1 of the present invention, it can be seen that the light energy LE1 irradiated in the optical sintering step is in the range of 95 to 100 J/cm ² suitable.

11 is a graph showing a method of irradiating light energy according to Experimental Example 2 of the present invention, FIG. 12 is a photograph of a ceramic sintered body according to Experimental Example 2 of the present invention, and FIG. 13 is a ceramic particle according to Comparative Example 1 of, FIG. 14 is a photograph of the ceramic sintered body according to Comparative Example 2, and FIG. 15 is a photograph of the ceramic sintered body according to Comparative Example 3.

According to Experimental Example 2 of the present invention, in the light sintering step, the light energy intensity of the set following the preceding set is greater than that of the preceding set, and the light energy intensity may be gradually increased and irradiated.

For example, as shown in Fig. 11, the first set of light energy is 70 J, the second set of light energy is 80 J, the third set of light energy is 90 J, and the fourth or fifth set of light energy is irradiated with 95 J can be

Accordingly, as shown in FIG. 12 , the ceramic sintered body 100S having a denser structure than the ceramic sintered body 100S of FIGS. 6 to 10 may be obtained.

That is, as described above, as the light energy intensity is gradually increased so that the light energy intensity irradiated from the set following the preceding set is greater than that of the preceding set, a sudden temperature rise that may be induced in the ceramic sintered body 100S and the substrate It is possible not only to minimize the , but also to obtain the ceramic sintered body 100S having a dense structure.

Meanwhile, the comparative examples shown in FIGS. 13 to 15 may be organized as shown in Table 2 below.

ceramic base sintering process Experimental Example 2 ceramic paste light sintering Comparative Example 1 ceramic powder N/A Comparative Example 2 ceramic powder light sintering Comparative Example 3 ceramic powder thermal sintering

Referring to FIG. 13 , in the ceramic particles according to Comparative Example 1, it can be confirmed that adjacent ceramic particles are not sintered, and the shape of each ceramic particle is maintained.

On the other hand, referring to FIG. 14 , the ceramic sintered body according to Comparative Example 2 is sintered from ceramic powder by light energy, does not form a dense structure, adjacent ceramic particles do not aggregate and grow, and most of them are in a necking state. You can check that you stayed in

15 , the ceramic sintered body according to Comparative Example 3 was grown by agglomeration between ceramic particles than in Comparative Example 2 as the ceramic powder was heat-treated at a high temperature of 1250 ° C. have.

That is, as in the experimental example of the present invention, the ceramic particles 100 are provided in the form of a paste, and the melting point is lower than that of the ceramic particles 100 , and heat generated by melting from the light energy LE1 is transferred to the ceramic particles. In the case of optical sintering, as shown in FIG. 12 , adjacent ceramic particles 100 grow ( 100G) to provide a ceramic sintered body 100S having a dense structure.

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

100: ceramic particles
100N: necking
100G: grown ceramic particles
100S: ceramic sintered body
100L: ceramic particle layer
200: additive
200M: molten additive
200L: additive layer
LS: light source
LE1: light energy

Claims (13)

delete preparing a ceramic paste including ceramic particles;
providing the ceramic paste on a substrate to form a ceramic particle layer including the ceramic particles;
forming an additive layer separate from the ceramic particle layer by providing an additive having a lower melting point than the ceramic particle on the ceramic particle layer; and
The additive is melted in the additive layer but the ceramic particles are irradiated with light energy in a range that does not melt the additive to melt the additive, and the molten additive penetrates between the adjacent ceramic particles of the ceramic particle layer, An optical sintering step in which a necking is formed between the adjacent ceramic particles by heat transferred from the melted and penetrated additive, and the adjacent ceramic particles having the necking formed are aggregated to grow the ceramic particles; sintering method.
3. The method of claim 2,
The ceramic paste further comprises an organic material,
Prior to the photo-sintering step, further comprising the step of preheating the substrate,
The method of claim 1, wherein the organic material is volatilized by preheating the substrate.
4. The method of claim 3,
The temperature at which the substrate is preheated is lower than the melting point of the additive, the optical sintering method of the ceramic.
delete 3. The method of claim 2,
The step of growing the ceramic particles comprises volatilizing the additive.
3. The method of claim 2,
The photo-sintering step, 90 J/cm ² More than 110 J/cm ² Light energy of less than 110 J/cm 2 The method of sintering ceramics comprising irradiating light.
3. The method of claim 2,
The optical sintering step is
Including that the light energy is irradiated in a plurality of sets,
comprising irradiating light energy in a plurality of pulses within the set;
and an interval between pulses within the set is less than an interval between the sets.
3. The method of claim 2,
The additive includes at least one selected from the group consisting of Li ₂ O ₃ , Bi ₂ O ₃ , CuO, and NiO.
3. The method of claim 2,
The ceramic particles, including at least one selected from the group consisting of perovskite or metal oxide, a method of optical sintering of ceramics. delete delete delete

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