KR102658302B1 - Molding method of conductive composite powder containing polytetra fluoroethylene and carbon nanotube and conductive composite powder molded article manufactured by using the same - Google Patents

Abstract

The present invention relates to a method for molding a conductive composite powder containing polytetra fluoroethylene and carbon nanotubes and to a conductive composite powder molded product manufactured using the same. A molding method for forming a bowl-shaped multi-structure molded product using a conductive composite powder containing nanotubes, comprising the step of pressing the conductive composite powder to form a compression molded product, forming the compression molded product. The steps include filling the first conductive composite powder into a base mold having a filling space, inserting an elastic mold into the base mold and placing it on the first conductive composite powder, and placing the elastic mold into the base mold into which the elastic mold is inserted. It provides a method for forming conductive composite powder, including filling the remaining space with a second conductive composite powder, placing a pressure mold on the elastic mold, and uniaxially pressing the pressure mold with a press device.

Description

Molding method of conductive composite powder containing polytetra fluoroethylene and carbon nanotube and conductive composite powder molded article manufactured by using the same the same}

The present invention relates to a method for molding a conductive composite powder containing polytetrafluoroethylene and carbon nanotubes and to a conductive composite powder molded product manufactured using the same, and specifically to a method for forming a conductive composite powder containing polytetrafluoroethylene and carbon nanotubes, and specifically to a method for forming a conductive composite powder containing polytetrafluoroethylene and carbon nanotubes. The present invention relates to a method for molding conductive composite powder that ensures uniform electrical conductivity characteristics, reduces raw materials, reduces waste, and improves processability, and to a molded product of conductive composite powder manufactured using the same.

When manufacturing electronic products, especially semiconductor products, if current flows through the product in an unintended manner or sparks are generated due to the current during the manufacturing process, product damage or defects may occur. Accordingly, parts of semiconductor manufacturing equipment such as transfer arms used to transfer semiconductor wafers, trays, chip mounting nozzles, wafer suction vacuum chucks, electrostatic chucks, and bowls are rarely or easily charged with static electricity. Eliminating anti-static performance is required.

In addition, parts for semiconductor manufacturing equipment require performance such as strong chemical resistance, non-toxicity, non-adhesiveness, and non-particle, and as a material to satisfy these performance, electrical conductivity is imparted to polymer resin. Various composite materials mixed with conductive fillers have been developed and used as materials for parts for semiconductor manufacturing equipment.

For example, carbon nanotubes are used to provide electrical conductivity to polytetra fluoroethylene (PTFE), which has excellent heat resistance, chemical resistance, electrical insulation, high frequency characteristics, non-stickiness, low coefficient of friction, and flame retardancy. , CNT), polytetrafluoroethylene-carbon nanotube (PTFE-CNT) composite material, which maintains the unique properties of PTFE and has certain conductivity to prevent static electricity, is used as a component material for semiconductor manufacturing equipment (especially semiconductor cleaning). It is used as a material for equipment bowls.

However, PTFE has the disadvantage that injection or extrusion molding is not possible due to poor moldability, fluidity, bondability, and density. Therefore, when molding an article using PTFE, PTFE powder is injected into a mold and compressed by a press to create a compression molded product of a certain shape, which is then sintered in a sintering furnace to solidify. Use the method instructed. However, although compression-sintering molding of PTFE material can form simple-shaped items, it cannot form complex-shaped items, so it requires a lot of processing, and the waste generated during the processing process is 50~50% depending on the shape. It occurs up to 90% and is the main cause of the increase in manufacturing costs due to the increase in processing costs and waste disposal costs.

In addition, molded products made of PTFE-CNT composite materials require uniform electrical conductivity characteristics, which requires high technical skills and increases the difficulty of the manufacturing process, further increasing the manufacturing cost, which further increases the need to reduce raw materials. can do.

Accordingly, the molding process using PTFE-CNT composite material requires a specialized molding process, unlike the general PTFE molding method, and in particular, the development of a new method for molding PTFE-CNT material articles of complex shapes is required.

The technology behind this application is disclosed in Korean Patent Publication No. 10-2004-0099139.

The technical problem to be solved by the present invention is to secure uniform electrical conductivity while maintaining the inherent properties of polytetrafluoroethylene material, as well as to provide a method for forming conductive composite powder with reduced raw materials, reduced waste, and improved processability, and the same. The purpose is to provide a conductive composite powder molded product manufactured using the present invention.

The problem to be solved by the present invention is not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the description below.

The method for forming a conductive composite powder according to embodiments of the present invention to achieve the above problem is to form a bowl using a conductive composite powder containing polytetra fluoroethylene and carbon nanotubes. ) in the molding method for forming a multi-structured molded product, comprising the step of pressing the conductive composite powder to form a compression molded product, wherein the step of forming the compression molded product is: forming a first mold in a base mold having a filling space. Filling conductive composite powder; Inserting an elastic mold into the base mold and placing it on the first conductive composite powder; Filling the remaining space of the base mold into which the elastic mold is inserted with a second conductive composite powder; and placing a pressure mold on the elastic mold, and uniaxially pressing the pressure mold with a press device, wherein while the pressure mold is uniaxially pressing, the elastic mold applies the pressure to the pressure mold to the uniaxial pressure. The first conductive composite powder and the second conductive composite powder are elastically deformed to be transmitted in a multi-axial direction including a first direction parallel to the direction and a second direction perpendicular to the first direction and parallel to the ground. .

According to one embodiment, uniaxially pressing the press mold with the press device includes: performing a first press process of pressurizing the press mold while boosting the pressure of the press device to a first pressure at a first pressurization rate. ; performing a first stabilization process of pressurizing the pressing mold for a first time while maintaining the first pressure; performing a second pressurizing process of pressurizing the pressurizing mold while increasing the pressure of the press device to a second pressure at a second pressurizing rate greater than the first pressurizing rate; And performing a second stabilization process of pressurizing the pressing mold for a second time while maintaining the second pressure, wherein the second pressure is 25 to 60 bar, and the first pressure is equal to the second pressure. It may be 1/3 to 1/2.

According to one embodiment, the first pressurization rate is 0.3 to 0.5 bar/min, the second pressurization rate is 0.8 to 1.2 bar/min, and each of the first time and the second time is the first pressurization This may be 1/3 to 2/3 of the time the process is performed.

According to one embodiment, the molding method further includes the step of sintering the compression molding using a sintering device, wherein the step of sintering the compression molding includes: raising the temperature of the sintering device to the maximum sintering temperature for a third time. Heating the compression molded product while increasing the temperature in a stepwise manner; and heating the compression molding for a fourth time while maintaining the maximum sintering temperature, wherein the maximum sintering temperature is 350 to 400° C., the third time is 8 to 12 hours, and the fourth time is 6. It may be from 12 hours to 12 hours.

According to one embodiment, the base mold has a hollow cylindrical shape with an open upper surface, the elastic mold has a pillar shape that can be inserted into the base mold through the open upper surface of the base mold, and the pressure mold has the It has a plate shape corresponding to the open upper surface of the base mold, wherein the second conductive composite powder is filled between the inner wall of the base mold exposed by the first conductive composite powder and the outer wall of the elastic mold, and 2 The filling height of the conductive composite powder may be lower than the upper surface of the elastic mold placed on the first conductive composite powder.

According to one embodiment, the base mold is provided inside the base mold and further includes an inner mold extending upward from a lower surface of the base mold toward the open upper surface, and the elastic mold is into which the inner mold is inserted. It may include a first through hole through which the inner mold can be inserted, and the pressurizing mold may include a second through hole through which the inner mold can be inserted.

According to one embodiment, the elastic mold is formed of a material containing at least one of rubber, urethane, and silicon, and the elastic mold may have a hardness of 20 to 60 Shore A.

Conductive composite powder molded products according to embodiments of the present invention to achieve the above object are manufactured by any one of the above methods.

According to embodiments of the present invention, the unique properties of the polytetrafluoroethylene material are achieved by compression molding and sintering the conductive composite powder under uniquely designed pressing conditions and sintering conditions using an elastic mold made of an elastically deformable material. It is possible to effectively form a bowl-shaped multi-structure molding that maintains uniform electrical conductivity characteristics. Through this, raw materials can be reduced by the volume of the elastic mold, processing waste can be reduced, and processability can be improved, thereby reducing costs.

As a result, it may be possible to provide a method for molding conductive composite powders that can secure the required physical properties while reducing raw materials, reducing waste, and improving processability.

1 is a flowchart for explaining a method of molding conductive composite powder according to embodiments of the present invention.
Figures 2 and 3 are diagrams for explaining a multi-structure molding manufactured by the method of Figure 1, respectively.
FIG. 4 is a flow chart specifying step S10 of FIG. 1.
Figure 5 is a diagram for explaining a press device and a mold structure used in the method of molding conductive composite powder according to embodiments of the present invention.
FIG. 6 is an exploded perspective view illustrating an example of a mold structure according to embodiments of the present invention, and FIG. 7 is an exploded perspective view illustrating another example of a mold structure according to embodiments of the present invention.
FIG. 8 is a diagram for explaining a compression molding process according to an embodiment of the present invention, and is a diagram corresponding to steps S11 to S13 of FIG. 2.
Figure 9 is a diagram for explaining the compression molding process according to an embodiment of the present invention, and is a diagram corresponding to step S14 of Figure 2.
Figure 10 is a graph to explain the compression molding process of conductive composite powder.
Figure 11 is a graph for explaining the sintering process of a compression molded product according to embodiments of the present invention.
Figure 12 is a diagram for explaining an application example of a conductive composite powder molded product manufactured according to embodiments of the present invention.
Figure 13 is a diagram for explaining the process of forming a multi-structure molding according to a general conventional method.

The advantages and features of the present invention and methods for achieving them will become clear by referring to the embodiments described in detail below along with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below and may be implemented in various different forms. The present embodiments are only provided to ensure that the disclosure of the present invention is complete and to provide common knowledge in the technical field to which the present invention pertains. It is provided to fully inform those who have the scope of the invention, and the present invention is only defined by the scope of the claims. The same reference numerals refer to the same elements throughout the specification.

In the present specification, when a member is said to be located “on” another member, this includes not only the case where a member is in contact with another member, but also the case where another member exists between the two members. In addition, in the specification of the present application, when a part "includes" a certain element, this means that it may further include other elements rather than excluding other elements, unless specifically stated to the contrary.

As used throughout the specification, the terms “about,” “substantially,” and the like are used to mean at or close to that value when manufacturing and material tolerances inherent in the stated meaning are given, and are understood herein. Precise or absolute figures are used to assist in preventing unscrupulous infringers from taking unfair advantage of the stated disclosure.

Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings.

1 is a flowchart for explaining a method of molding conductive composite powder according to embodiments of the present invention. Figures 2 and 3 are diagrams for explaining a multi-structure molding manufactured by the method of Figure 1, respectively.

Referring to Figure 1, the method of forming a conductive composite powder according to embodiments of the present invention uses a conductive composite powder containing polytetra fluoroethylene and carbon nanotubes to form a bowl. ) It relates to a molding method for forming a multi-structured molded product, which may include the step of forming a compression molded product by pressing conductive composite powder (S10) and the step of sintering the compression molded product using a sintering device (S20). .

In the present invention, the conductive composite powder is a polytetrafluoroethylene-carbon nanotube (PTFE-CNT) composite that combines polytetrafluoroethylene (PTFE) with carbon nanotubes (CNTs) for imparting electrical conductivity. As a material, it can be a composite powder that maintains the unique properties of PTFE and has certain conductivity. Since the conductive composite powder of polytetrafluoroethylene-carbon nanotubes (PTFE-CNT) can be manufactured using a known method, a detailed description thereof will be omitted.

In this specification, a compression molded product refers to the state before sintering as a result of compression molding of a conductive composite powder, and the resulting product in a state in which sintering of the compression molded product is completed may be referred to as a sintered body.

In the present invention, the sintered body may be implemented as a bowl-shaped multi-structure molding (10A, 10B). The bowl-shaped multi-structure molding is a sintered body of a compression molding formed by multi-axial pressing. As shown in Figure 2 or 3, the plate-shaped bottom BP and the edges of the bottom BP are formed. It may include a bowl-shaped structure including an upwardly extending side wall portion (SWP). In particular, in the case of the multi-structure molded product 10B of FIG. 3, a central hole CH penetrating the bottom BP may be formed in the center of the bottom BP.

That is, the method of forming a conductive composite powder according to embodiments of the present invention forms a bowl-shaped compression molded product through a compression molding process of pressurizing the conductive composite powder, and sinteres the compression molded product through a sintering process to form a multi-layered composite powder. It may be a molding method for forming a molded product of a structure.

First, referring to FIGS. 4 to 10, a compression molding process for pressurizing conductive composite powder will be described.

FIG. 4 is a flowchart specifying step S10 of FIG. 1. Figure 5 is a diagram for explaining a press device and a mold structure used in the method of molding conductive composite powder according to embodiments of the present invention. FIG. 6 is an exploded perspective view illustrating an example of a mold structure according to embodiments of the present invention, and FIG. 7 is an exploded perspective view illustrating another example of a mold structure according to embodiments of the present invention. FIG. 8 is a diagram for explaining a compression molding process according to an embodiment of the present invention, and is a diagram corresponding to steps S11 to S13 of FIG. 2. Figure 9 is a diagram for explaining the compression molding process according to an embodiment of the present invention, and is a diagram corresponding to step S14 of Figure 2. Figure 10 is a graph to explain the compression molding process of conductive composite powder.

Referring to Figures 4 to 10, the step of forming a compression molded product by pressing the conductive composite powder includes filling the first conductive composite powder into a base mold having a filling space (S11), and inserting the elastic mold into the base mold. Placing the first conductive composite powder on the first conductive composite powder (S12), filling the remaining space of the base mold into which the elastic mold is inserted with the second conductive composite powder (S13), and placing the pressure mold on the elastic mold, It may include uniaxially pressing the press mold with a press device (S14).

That is, in the present invention, the compression molding process of pressing the conductive composite powder can be performed using the press device 100 and the mold structure 200.

The press device 100 may be a typical single-axis press device. For example, as shown in FIG. 5, the press device 100 may include a lower fixing plate 110 and an upper driving plate 120 that is movable up and down with respect to the lower fixing plate 110. As long as the press device 100 has a structure that generates sufficient compressive force, either a mechanical press or a hydraulic press can be used. Since the remaining components are the same or similar to those of the normal press device 100, detailed description is omitted. .

The mold structure 200 may include a base mold 210, an elastic mold 220, and a pressure mold 230.

The base mold 210 may be provided with a filling space in which the conductive composite powder is filled. For example, the base mold 210 may have a hollow cylindrical shape with an open top. The base mold 210 may be made of a metal material, but the present invention is not limited thereto.

The elastic mold 220 may be inserted into the base mold 210 through the open upper surface of the base mold 210, and may be made of an elastically deformable material. For example, the elastic mold 220 may be formed of a material containing at least one of rubber, urethane, and silicon.

The elastic mold 220 made of an elastically deformable material can transmit the uniaxial pressing force of the press device 100 in multiaxial directions to press the conductive composite powder filled in the base mold 210 in multiaxial directions. For effective pressure transfer and pressurization, the elastic mold 220 may have a hardness of 20 to 60 Shore A.

The elastic mold 220 may be formed as a single piece or may be formed by stacking a plurality of sub-elastic molds with a certain height.

The pressure mold 230 may have a plate shape corresponding to the open upper surface of the base mold 210, and the uniaxial pressure applied by the lowering of the upper driving plate 120 of the press device 100 is applied to the elastic mold 220. ) and conductive composite powder. The pressure mold 230 may be made of a metal material, but the present invention is not limited thereto.

The shape of the mold structure 200 may be modified into various forms depending on the shape of the multi-structure molded product.

In one embodiment, when the multi-structure molding to be formed corresponds to the structure 10A of FIG. 2, as shown in FIG. 6, the base mold 210 has a cylindrical shape with an open upper surface, and is an elastic mold ( 220 may have a cylindrical shape having a diameter that can be inserted into the base mold 210, and the pressure mold 230 may have a disk shape.

In another embodiment, when the multi-structure molding to be formed corresponds to the structure 10B of FIG. 3, the base mold 210 is provided inside the base mold 210, as shown in FIG. 7, and the base It may further include an inner mold 214 extending upward from the lower surface of the mold 210 toward the open upper surface. At this time, the elastic mold 220 includes a first through hole 220h through which the inner mold 214 can be inserted, and the pressure mold 230 includes a second through hole 230h through which the inner mold 214 can be inserted. ) may include.

For example, in the embodiment of FIG. 7, the side wall of the base mold 210 may correspond to the outer mold 212, the lower surface may correspond to the bottom mold 216, and the base mold 210 may correspond to the outer mold 212. It may have a structure in which an inner mold 214 is inserted. That is, the base mold 210 is a form in which an inner mold 214 having a smaller outer diameter than the outer mold 212 is inserted into an outer mold 212 having a hollow pipe shape with both sides open, and the outer mold 212 It may have a structure in which the bottom mold 216 is connected to adjacent ends of the inner mold 214. At this time, the inner mold 214 may be in the shape of a hollow pipe with both sides open, but the present invention is not limited to this. Unlike shown, the inner mold 214 may have a pillar shape. Additionally, the bottom mold 216 may have a disk shape with a through hole 216h formed in the center.

In this embodiment, the outer mold 212, the inner mold 214, and the bottom mold 216 are formed as one body, or the molds 212, 214, and 216 are combined to form the base mold 210. It could be.

Hereinafter, the compression molding process of the conductive composite powder performed using the mold structure 200 of FIG. 7 will be described in more detail.

As shown in FIG. 8, the first conductive composite powder is evenly filled into the base mold 210 to the first height (see (a) of FIG. 8), and the elastic mold 220 is placed on the first conductive composite powder. After that (see (b) in FIG. 8), the remaining space within the base mold 210 can be filled with the second conductive composite powder to a second height (see (c) in FIG. 8). Here, the first conductive composite powder may correspond to the conductive composite powder primarily filled in the base mold 210, and the second conductive composite powder may correspond to the conductive composite powder secondarily filled in the base mold 210.

The second conductive composite powder is filled in the space between the inner wall of the base mold 210 exposed by the first conductive composite powder and the outer wall of the elastic mold 220, and the filling height of the second conductive composite powder, that is, the second The height may be lower than the upper surface of the elastic mold 220 disposed on the first conductive composite powder.

Next, as shown in FIG. 9, the pressure mold 230 is placed on the elastic mold 220 (see (d) of FIG. 9), and the pressure mold 230 is uniaxially pressed with the press device 100. (See Figure 9(e)) A compression molding process of the conductive composite powder can be performed.

While the pressing mold 230 is uniaxially pressed, the elastic mold 220 is elastically deformed to transmit the pressure applied to the pressing mold 230 in a multi-axial direction, thereby pressurizing the first conductive composite powder and the second conductive composite powder. there is. Here, the multi-axial direction may include a first direction D1 parallel to the uniaxial pressing direction and a second direction D2 perpendicular to the first direction D1 and parallel to the ground. The second direction D2 may be each circumferential direction along the circumference of the elastic mold 220 based on a certain height point of the elastic mold 220.

When it is desired to form a multi-structured compression molded product using the elastic mold 220, the pressurizing conditions of the press device 100 must be uniquely designed in order to secure uniform electrical conductivity characteristics while maintaining the unique characteristics of the conductive composite powder. There is a need.

For example, in addition to effectively transmitting the pressure applied to the elastic mold 220 in multiple axes, it ensures that even pressure is transmitted to vulnerable parts of the base mold 210, and prevents damage due to differences in density of the conductive composite powder in the space. In order to prevent this from occurring, the pressurization conditions of the press device 100 may be designed to reach the maximum pressure through a two-stage pressurization process at different speeds. Additionally, a stabilization process may be performed for a certain period of time after the pressurization process to smoothly discharge gas (eg, air) generated during compression molding.

Specifically, referring to FIG. 10, uniaxially pressing the press mold 230 with the press device 100 involves increasing the pressure of the press device 100 to the first pressure P1 at a first pressurization rate while forming the press mold ( Performing a first pressurizing process of pressurizing the press mold 230), performing a first stabilization process of pressurizing the press mold 230 for a first time t1 while maintaining the first pressure P1, press device ( Performing a second pressurizing process of pressurizing the pressurizing mold 230 while increasing the pressure of 100) to a second pressure (P2) at a second pressurizing rate greater than the first pressurizing rate, and increasing the second pressure (P2) It may include performing a second stabilization process of pressurizing the pressurizing mold 230 for a second time t2.

Here, the pressurizing conditions (e.g., maximum pressure, pressurization rate, stabilization time, etc.) of the press device 100 may vary depending on the volume of the compression molding to be formed and the electrical conductivity characteristics to be implemented (e.g., standard resistivity value). .

For example, the second pressure (P2), which is the maximum pressure, may be 25 to 60 bar, and the first pressure (P1) may be 1/3 to 1/2 of the second pressure (P2). At this time, the first pressure increase rate of the first pressurization process may be 0.3 to 0.5 bar/min, and the second pressure increase rate of the second pressurization process may be 0.8 to 1.2 bar/min. In addition, each of the first time t1 and the second time t2, which are the performance times of the stabilization process, may be 1/3 to 2/3 of the time the first pressurization process is performed.

In this way, the pressure mold 230 and the elastic mold 220 can press the conductive composite powder by the pressure of the press device 100 to form a compression molded product. In particular, the elastic mold 220 can press the conductive composite powder in multi-axial directions. By pressing, a similar effect to isostatic pressing can be achieved, and thus, effective formation of a multi-structured compression molded product may be possible.

The compression molded product of the conductive composite powder formed through the compression molding process as described above may be sintered through a sintering process using a sintering device to form a sintered body.

Since the sintering device can use a typical sintering device (e.g., sintering furnace, oven, etc.), detailed description thereof will be omitted.

When sintering a conductive material containing a conductive material such as carbon nanotubes (CNTs), if it is exposed to a temperature exceeding the limit for a long time due to the Van de Waals force of the carbon nanotubes (CNTs), it is dispersed inside the compression molded product. Agglomeration of carbon nanotubes (CNTs) may occur, resulting in conductivity imbalance inside the sintered body. In addition, when sintering at a low temperature, the sintering effect is insufficient and the strength of the material is not sufficiently secured, which may cause defects (e.g., cracks) on the internal surface after processing.

Therefore, as in the present invention, the sintering process of a multi-structured compression molding made of a conductive material containing a conductive material such as carbon nanotubes (CNT) prevents defects (e.g. cracks) on the internal surface after processing by improving strength. In addition, it needs to be performed under unique sintering conditions to ensure uniform conductivity.

Specifically, when describing the sintering process of a compression molded product according to embodiments of the present invention with reference to FIG. 11, the step of sintering a compression molded product using a sintering device (S20) involves adjusting the temperature of the sintering device for a third time (t3). ) may include heating the compression molding while gradually increasing the temperature to the maximum sintering temperature (Tmax) and heating the compression molding for a fourth time (t4) while maintaining the maximum sintering temperature (Tmax). Here, FIG. 11 is a graph for explaining the sintering process of a compression molded product according to embodiments of the present invention.

In the present invention, the maximum sintering temperature (Tmax) may be 350 to 400° C., and the maintenance time of the maximum sintering temperature (Tmax) may be preferably at least 6 hours or more.

This stepwise temperature rise time and the maintenance time of the maximum sintering temperature (Tmax) may vary depending on the volume of the compression molding. For example, the third time (t3), which is the step temperature increase time, may be 8 to 12 hours, and the fourth time (t4), which is the maintenance time of the maximum sintering temperature (Tmax), may be 6 to 12 hours.

After completion of the sintering process, the sintered body may be slowly cooled to approximately 200° C. in the sintering device and then naturally cooled to room temperature.

The sintered body formed in this way can be manufactured into a conductive composite powder molded product through a processing process. The machining process may use conventional methods (e.g., cutting process, etc.), so detailed description thereof will be omitted.

As an example, the conductive composite powder molded product manufactured according to embodiments of the present invention can be used as the bowl part 510 of the semiconductor cleaning device 500 as shown in FIG. 12. However, the present invention is not limited to this. Here, Figure 12 is a diagram for explaining an application example of a conductive composite powder molded product manufactured according to embodiments of the present invention.

As shown in Figure 13, when forming a multi-structure molding of conductive composite powder according to a general method, the conductive composite powder in which carbon nanotubes are bonded to polytetrafluoroethylene is pressed to form a compression molding in the form of a pillar or pipe. This was then sintered to produce a sintered body (see 50 in FIG. 13), which was then processed to produce a conductive composite powder molded product (for example, a bowl part of a semiconductor cleaning device). In this case, the central area of the sintered body was discarded during the processing process, generating a large amount of processing waste and increasing processing difficulty. Here, Figure 13 is a diagram for explaining the process of forming a multi-structure molding according to a general conventional method.

However, according to embodiments of the present invention, the conductive composite powder is compression molded and sintered according to uniquely designed pressing conditions and sintering conditions using an elastic mold 220 made of an elastically deformable material, thereby forming a polytetrafluoroethylene material. It is possible to effectively form a bowl-shaped multi-structured molding with uniform electrical conductivity characteristics while maintaining the original characteristics. Through this, raw materials can be reduced by the volume of the elastic mold 220, processing waste can be reduced, and processability can be improved, thereby reducing costs.

As a result, it may be possible to provide a method for molding conductive composite powders that can secure the required physical properties while reducing raw materials, reducing waste, and improving processability.

Although embodiments of the present invention have been described above with reference to the attached drawings, those skilled in the art will understand that the present invention can be implemented in other specific forms without changing its technical idea or essential features. You will understand that you can. Therefore, the embodiments and application examples described above should be understood as illustrative in all respects and not restrictive.

10A, 10B: Multi-structure molding
100: press device 200: mold structure
210: base mold 220: elastic mold
230: Pressurized mold

Claims (8)

In the molding method of forming a bowl-shaped multi-structure molding using a conductive composite powder containing polytetra fluoroethylene and carbon nanotubes,
Comprising the step of pressing the conductive composite powder to form a compression molded product,
The steps for forming the compression molding are:
Filling the first conductive composite powder into a base mold having a filling space;
Inserting an elastic mold into the base mold and placing it on the first conductive composite powder;
Filling the remaining space of the base mold into which the elastic mold is inserted with a second conductive composite powder; and
Including placing a pressure mold on the elastic mold and uniaxially pressing the pressure mold with a press device,
While the pressing mold is uniaxially pressed, the elastic mold applies pressure to the pressing mold in a first direction parallel to the direction of the uniaxial pressing and a second direction perpendicular to the first direction and parallel to the ground. A method of forming a conductive composite powder in which the first conductive composite powder and the second conductive composite powder are elastically deformed so as to be transmitted in a multi-axial direction and pressed. According to claim 1,
Uniaxially pressing the press mold with the press device:
performing a first pressurizing process of pressurizing the pressurizing mold while increasing the pressure of the press device to a first pressure at a first pressurizing rate;
performing a first stabilization process of pressurizing the pressing mold for a first time while maintaining the first pressure;
performing a second pressurizing process of pressurizing the pressurizing mold while increasing the pressure of the press device to a second pressure at a second pressurizing rate greater than the first pressurizing rate; and
and performing a second stabilization process of pressurizing the pressing mold for a second time while maintaining the second pressure,
The second pressure is 25 to 60 bar, and the first pressure is 1/3 to 1/2 of the second pressure. According to clause 2,
The first pressure boosting rate is 0.3 to 0.5 bar/min,
The second pressure boosting rate is 0.8 to 1.2 bar/min,
Each of the first time and the second time is 1/3 to 2/3 of the time during which the first pressing process was performed. According to clause 2,
The molding method further includes the step of sintering the compression molded product using a sintering device,
The steps for sintering the compression molding are:
heating the compression molding while gradually increasing the temperature of the sintering device to a maximum sintering temperature for a third time; and
and heating the compression molding for a fourth time while maintaining the maximum sintering temperature,
The maximum sintering temperature is 350 to 400°C,
the third time is 8 to 12 hours,
The fourth time is 6 to 12 hours. According to clause 4,
The base mold has a hollow cylindrical shape with an open upper surface,
The elastic mold has a pillar shape that can be inserted into the base mold through the open upper surface of the base mold,
The pressure mold has a plate shape corresponding to the open upper surface of the base mold,
The second conductive composite powder is filled between the inner wall of the base mold exposed by the first conductive composite powder and the outer wall of the elastic mold,
A method of forming a conductive composite powder wherein the filling height of the second conductive composite powder is lower than the upper surface of the elastic mold disposed on the first conductive composite powder. According to clause 5,
The base mold further includes an inner mold provided inside the base mold and extending upward from a lower surface of the base mold toward the open upper surface,
The elastic mold includes a first through hole through which the inner mold can be inserted,
The pressurizing mold is a method of forming a conductive composite powder including a second through hole through which the inner mold can be inserted. According to clause 2,
The elastic mold is formed of a material containing at least one of rubber, urethane, and silicone,
The elastic mold is a method of forming a conductive composite powder having a hardness of 20 to 60 Shore A. A conductive composite powder molded article manufactured by the method of any one of claims 1 to 7.