KR20200080964A - Metal-carbon composite structure, composite film comprising the same, and method of fabrication of the same - Google Patents

Abstract

The present invention is to provide a metal-carbon composite structure, a composite sheet including the same, and a manufacturing method thereof. A manufacturing method of the metal-carbon composite structure is provided. According to the present invention, the manufacturing method of the metal-carbon composite structure may comprise the steps of: preparing a metal oxide; pulverizing the metal oxide to produce fine particles; mixing the fine particles in a solvent to produce a slurry; distributing the slurry in a chamber and drying to produce an aggregate; obtaining and reducing the aggregate to produce the metal particles; flattening the metal particles to produce a flattened metal structure; and mixing the metal structure with the carbon source and heat treating to produce a metal-carbon composite structure in which a graphitic carbon layer is coated on a surface of the metal structure.

Description

Metal-carbon composite structure, a composite sheet comprising the same, and a method of manufacturing the same {Metal-carbon composite structure, composite film comprising the same, and method of fabrication of the same}

The present application relates to a metal-carbon composite structure, a composite sheet comprising the same, and a method for manufacturing the same, and more specifically, a metal-carbon composite structure in which a graphite carbon layer is coated on a metal structure, electromagnetic wave shielding properties, and electromagnetic wave absorption It relates to a composite sheet having a property, a high thermal conductivity property, a high heat dissipation property, and comprising a metal-carbon composite structure, and a method for manufacturing the same.

Recently, various digital electronic devices such as PCs, portable terminals, and portable media players have been widely used. Accordingly, there is a problem in that electromagnetic waves generated in electronic devices affect other electronic devices through space or affect other electronic devices through wires or PCBs, and cause malfunction.

These electromagnetic disturbances, ranging from computer malfunctions to factory burnout accidents, are appearing in various ways, and as research results in which electromagnetic waves negatively affect the human body have been announced one after another, health concerns and concerns are increasing. In addition, with the emphasis on strengthening regulations on electromagnetic interference and preparing countermeasures, mainly in developed countries, electromagnetic absorption and shielding technologies for various electronic and electrical products are emerging as core technology fields in the electronics industry.

Accordingly, various technologies for absorbing and shielding electromagnetic waves have been developed. For example, Korea Patent Registration Publication 10-0995563 (Application No. 10-2010-0041847, Applicant Inox Co., Ltd.) has excellent adhesive strength, heat resistance, electrical conductivity, flexibility, etc., and can be applied to flexible printed circuit boards. Conductive adhesive films are disclosed.

One technical problem to be solved by the present application is to provide a metal-carbon composite structure, a composite sheet including the same, and a manufacturing method thereof.

Another technical problem to be solved by the present application is to provide a metal-carbon composite structure coated with a graphite carbon layer on a metal structure, and a method for manufacturing the same.

Another technical problem to be solved by the present application is to provide a composite sheet having improved electromagnetic wave absorption and electromagnetic wave shielding properties, and a manufacturing method thereof.

Another technical problem to be solved by the present application is to provide a composite sheet having high thermal conductivity properties, and a method for manufacturing the same.

Another technical problem to be solved by the present application is to provide a composite sheet having high heat dissipation properties, and a manufacturing method thereof.

Another technical problem to be solved by the present application is to provide a method of manufacturing a metal-carbon composite structure with a simplified manufacturing process, and a method of manufacturing a composite sheet comprising the same.

Another technical problem to be solved by the present application is to provide a method of manufacturing a metal-carbon composite structure with reduced manufacturing cost, and a method of manufacturing a composite sheet including the same.

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

To solve the above technical problem, the present application provides a method for manufacturing a metal-carbon composite structure.

According to one embodiment, the method of manufacturing the metal-carbon composite structure comprises: preparing a metal oxide, crushing the metal oxide, preparing fine particles, mixing the fine particles with a solvent, and preparing a slurry Step of dispersing and drying the slurry in a chamber to prepare agglomerates, obtaining and reducing the agglomerates, producing metal particles, flaking the metal particles, and producing a flattened metal structure And mixing and heat-treating the metal structure with a carbon source to produce a metal-carbon composite structure coated with a graphite carbon layer on the surface of the metal structure.

According to one embodiment, the step of manufacturing the aggregate includes spraying the slurry into the chamber using a spray gas, but includes controlling the size of the aggregate according to the specific gravity of the spray gas. Can.

According to one embodiment, the method of manufacturing the metal-carbon composite structure, before mixing the metal structure with the carbon source, heat-treating the metal structure to remove internal stress of the flattened metal structure. It may further include.

According to an embodiment, the carbon source may include sucrose.

In order to solve the above technical problem, the present invention provides a method for manufacturing a composite sheet.

According to one embodiment, the method of manufacturing the composite sheet comprises: preparing a metal-carbon composite structure according to the above-described embodiment, and mixing the metal-carbon composite structure with a binder to produce a composite sheet. It can contain.

According to an embodiment, the metal structure may include an alloy of iron and nickel.

According to an embodiment of the present invention, a metal oxide is prepared, the metal oxide is pulverized to prepare fine particles, and the fine particles are mixed in a solvent to prepare a slurry, and the slurry is divided into a chamber and dried. Agglomerates are prepared, the agglomerates are obtained and reduced, metal particles are produced, the metal particles are flattened, a flattened metal structure is prepared, and the metal structure is mixed with a carbon source and heat treated to form graphite. A metal-carbon composite structure in which a carbonic layer is coated on the surface of the metal structure may be prepared, and a composite sheet may be prepared by mixing the metal-carbon composite structure and a binder.

By using the metal-carbon composite structure coated with the graphite carbon layer on the flattened metal structure, the density of the metal-carbon composite structure in the composite sheet may be improved, and accordingly, thermal conductivity, Heat dissipation characteristics, electromagnetic wave absorption and electromagnetic wave shielding characteristics may be improved.

In addition, in the step of preparing the agglomerate, the size of the agglomerate can be controlled according to the specific gravity of the spray gas spraying the slurry into the chamber, and thereby, the size of the metal-carbon composite structure can be easily controlled. Can.

In addition, the aggregate used in the production of the metal-carbon composite structure can be controlled in shape by controlling the internal temperature of the chamber in which the fine particles are sprayed. Accordingly, the agglomerate can be made into a spherical shape, and the metal particles made from the agglomerate can be made into a spherical shape. Due to this, the metal structure and the metal-carbon composite structure can be easily produced, and the thermal conductivity, heat dissipation properties, electromagnetic wave absorption, and electromagnetic wave shielding properties of the composite sheet including the metal-carbon composite structure are improved. And the reliability of the manufacturing process can be improved.

1 is a flowchart illustrating a method of manufacturing a metal-carbon composite structure according to an embodiment of the present invention.
2 is a view for explaining an apparatus for producing an aggregate used in the production of a metal-carbon composite structure according to an embodiment of the present invention.
3 is an XRD analysis result of Fe2O3 and NiO used in the manufacture of a composite sheet according to an embodiment of the present invention.
4 is an SEM photograph of Fe2O3 and NiO aggregates used in the manufacture of a composite sheet according to an embodiment of the present invention.
5 is an XRD result graph of metal particles used in the manufacture of a composite sheet according to an embodiment of the present invention.
6 is an SEM photograph of a metal structure used in the manufacture of a composite sheet according to an embodiment of the present invention.
7 is an SEM photograph of a metal structure and commercial permalloy flakes used in the manufacture of a composite sheet according to an embodiment of the present invention.
8 is a SEM photograph of the metal structure used in the production of the composite sheet according to an embodiment of the present invention according to the heat treatment process temperature.
9 is a graph measuring magnetization and coercive forces of Fe2O3 and NiO aggregates, metal structures, and heat-treated metal structures according to an embodiment of the present invention.
10 is a Raman analysis result of a metal-carbon composite structure prepared according to an embodiment 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 to ensure that the disclosed contents are thorough and complete and that the spirit of the present invention is sufficiently conveyed to those skilled in the art.

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

Further, in various embodiments of the present specification, terms such as first, second, and third 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 component. Therefore, what is referred to as the first component in one embodiment may be referred to as the second component in another embodiment. Each embodiment described and illustrated herein also includes its complementary embodiment. Also, in this specification,'and/or' is used to mean including at least one of the components listed before and after.

In the specification, a singular expression includes a plural expression unless the context clearly indicates otherwise. Also, terms such as “include” or “have” are intended to indicate the presence of features, numbers, steps, elements, or combinations thereof described in the specification, but one or more other features, numbers, steps, or configurations. It should not be understood as excluding the possibility or presence of elements or combinations thereof.

In addition, in the following description of the present invention, when it is determined that detailed descriptions of related known functions or configurations may unnecessarily obscure the subject matter of the present invention, detailed descriptions thereof will be omitted.

1 is a flow chart for explaining a method of manufacturing a metal-carbon composite structure according to an embodiment of the present invention, Figure 2 is an apparatus for producing an aggregate used in the production of a metal-carbon composite structure according to an embodiment of the present invention It is a figure for illustration.

1 and 2, a metal oxide is prepared (S110). According to an embodiment, the metal oxide may be iron oxide and nickel oxide. Alternatively, according to another embodiment, the metal oxide may include at least one of tungsten oxide, copper oxide, molybdenum oxide, or chromium oxide.

By pulverizing the metal oxide, fine particles may be prepared (S120). The metal oxide may be pulverized by a mechanical grinding method (eg, ball milling method). Specifically, the metal oxide is pulverized for 1 to 15 hours at 2400 rpm using a steel bead, dried at 70° C. for 24 hours, and classified using an 80 mesh standard mesh. In addition, for example, in order to minimize the generation of impurities, a ball milling process may be performed using 3Φ Zirconia bead.

According to one embodiment, together with the metal oxide, additives, etc. may be crushed together. For example, the additive may include a metal of a different type from the metal oxide. In this case, as described later, when a spray drying and reduction process is performed, alloy particles of a metal contained in the additive and a metal contained in the metal oxide may be prepared. For example, when iron oxide and nickel oxide are pulverized together, and a spray drying and reduction process is performed as described below, iron-nickel alloy particles may be produced. For another example, the additive may be a polymer material, in which case the metal oxide can be easily crushed into particles having a certain size. The polymer material may be removed in an aggregate manufacturing process described below.

By mixing the fine particles in a solvent, a slurry may be prepared (S130). For example, the slurry may be prepared by mixing a solvent containing PCA (process, control agent, for example, methyl alcohol, ethyl alcohol, acetone, water, etc.) in the fine particles.

Alternatively, when the metal oxide is pulverized by a wet ball milling method, a slurry-like material immediately after ball milling can be sprayed, as described below, to produce an aggregate.

The slurry containing the fine particles may be sprayed into the chamber 240 and dried to prepare aggregates (S140).

The slurry is prepared in the slurry tank 210, the compressor 230 reduces the pressure inside the chamber 240, and using the feed pump 220, the chamber 240 in the slurry tank 210 The slurry can be supplied. The fine particles in the slurry are spray dried to agglomerate with each other, and accordingly, the agglomerates may be formed in the chamber 240.

According to an embodiment of the present invention, by controlling the temperature inside the chamber 240, the shape of the aggregate can be controlled. Specifically, as the temperature inside the chamber 240 is lower, the agglomerate may be manufactured in a shape close to a sphere. On the other hand, when the temperature inside the chamber 240 is high, the agglomerate is not manufactured in a spherical shape. For example, when the temperature inside the chamber 240 is 30°C, the agglomerate may be made into a spherical shape, but when it is 50°C or more inside the chamber 240, the agglomerate may not be made into a spherical shape. In addition, the lower the temperature inside the chamber 240, the lower the production yield of the aggregate may be. Accordingly, the internal temperature of the chamber 240 can be controlled to a maximum of less than 50 ℃.

By the friction of the fine particles contained in the slurry supplied to the chamber 240, the temperature inside the chamber 240 may increase as the reaction continues. Accordingly, according to an embodiment of the present invention, in order to control the temperature inside the chamber 240, a cooling device may be used inside and outside the chamber 240.

Metal particles may be produced by obtaining and reducing the aggregate (S150). When the metal oxide is iron oxide as described above, the metal particles may be iron. Alternatively, when the metal oxide includes iron oxide and nickel oxide, the metal particles may be alloys of iron and nickel.

As illustrated in FIG. 2, an exhaust pump 250 exhausts the inside of the chamber 250, and the agglomerates can be obtained in the first and second tanks 260 and 270. The first obtaining tank 260 may be relatively connected to the lower portion of the chamber 240, and the second obtaining tank 270 may be relatively connected to the upper portion of the chamber 240. Accordingly, the aggregate having a relatively large size may be obtained in the first obtaining tank 260, and the aggregate having a relatively small size may be obtained in the second obtaining tank 270.

Further, according to an embodiment, in the process in which the slurry is sprayed from the slurry tank 210 to the chamber 240, spray gas may be used. The atomizing gas may be argon gas or atmospheric gas, for example.

According to one embodiment, depending on the specific gravity of the spray gas, the size of the aggregate may be controlled. Specifically, when the specific gravity of the spray gas is relatively small, for example, when the spray gas is argon gas, the amount of aggregates obtained in the second obtaining tank 270 may be relatively increased. In other words, when the specific gravity of the spray gas is relatively small, the yield of the small-sized aggregate can be increased. On the other hand, when the specific gravity of the spray gas is relatively large, for example, when the spray gas is an atmospheric gas, the amount of aggregates obtained in the first obtaining tank 260 may be relatively increased. In other words, when the specific gravity of the spray gas is relatively large, the yield of the aggregate having a large size may be increased.

The agglomerates can be reduced by heat treatment. Specifically, it may be reduced by, for example, heat treatment in a hydrogen atmosphere at 200 to 800°C.

According to one embodiment, depending on the size of the agglomerate, the temperature at which the agglomerate is heat treated may be adjusted.

By flattening the metal particles, a flattened metal structure can be produced (S160). According to one embodiment, the metal particles may be flattened using an Attrition mill. For example, 200rpm, Zrconia bead 3Φ, the metal particles: bead weight ratio = 1: 5, the knitting process may be performed under the conditions of 1 ~ 12hr.

As the milling time increases, the aspect ratio of the flattened metal structure increases, and the thickness may decrease. According to one embodiment, when the 10-hour laceration process is performed, the aspect ratio is the largest with 20:1, and the amount of fine powder can be minimized.

By heat-treating the metal structure, stress inside the metal structure may be removed. According to an embodiment, the heat treatment may be performed at a temperature of 600 to 900° C. and a hydrogen gas atmosphere for 1 hour, and the temperature may be raised to 5° C./min.

According to an embodiment, the metal structure may be heat-treated so that the phase change of the metal structure does not occur, thereby removing the internal stress of the metal structure. For example, the metal structure may be heat treated at 600°C.

In addition, when the internal stress of the metal structure is removed by the heat treatment process, the powder shape may be recovered again by local bonding and particle growth of the metal structure. For example, when the metal structure is heat-treated at 900°C or higher, localization of the metal structure may lower the level of dl. Therefore, the metal structure may be heat-treated at less than 900°C.

A metal-carbon composite structure in which a carbon layer is coated on the surface of the metal structure may be prepared by mixing the metal structure with a carbon source and heat-treating it (S170).

According to an embodiment, the manufacturing of the metal-carbon composite structure may include mixing the carbon source and the metal structure, wetting the metal structure, and drying (eg, 100° C., 24 hours). ), 1st heat treatment (for example, 250°C, 8 hours), 2nd heat treatment (for example, 900°C, 4 hours), and classification (for example, using 80 mesh standard mesh) It may include, the carbon source, Saccharouse (D(+)-Sucrose): DI water = may be a mixture of 4:9.

According to another embodiment, the step of preparing the metal-carbon composite structure comprises: preparing a carbon source, preparing a carbon source by bonding a functional group to the carbon source, mixing the carbon source and the metal structure, and The method may include coating a metal structure with the carbon source, and heat treating the metal structure coated with the carbon source. For example, the carbon source may be cellulose, and the functional group may be alcohol (methanol, ethanol, etc.), water, terpineol. Specifically, the carbon source may be prepared by mixing and drying the carbon source and the functional group.

The metal structure coated with the carbon source may be heat treated in an oxygen-free atmosphere (eg argon or nitrogen gas). For example, it may be heat treated at 850 ~ 1,100 ℃ for 8 hours.

By the heat treatment, the carbon source on the surface of the metal structure is carbonized, and the graphite carbon layer may be formed on the surface of the metal structure.

According to an embodiment, after the heat treatment process is performed, the amorphous carbon, which is not converted into the carbon layer, may be removed by a washing process and a disintegration process using hydrogen peroxide.

Subsequently, a composite sheet using a metal-carbon composite structure manufactured according to the above-described embodiment and a method of manufacturing the same are described.

The metal-carbon composite structure can be mixed with a binder to produce a composite sheet. Specifically, the step of manufacturing the composite sheet may be prepared by a process of mixing the metal-carbon composite structure and a binder, defoaming, sheet forming, drying, and pressing.

According to an embodiment of the present invention, the metal oxide is pulverized to prepare the fine particles, the fine particles are mixed with a solvent to prepare a slurry, the slurry is sprayed in a chamber, and dried to produce aggregates, Agglomerates are obtained and reduced to produce the metal particles, and the metal particles are flattened to produce the metal structure, the metal structure is mixed with a carbon source, and heat treated to produce a metal-carbon composite structure, and the A composite sheet can be prepared by mixing a metal-carbon composite structure with a binder. As the metal structure coated with the carbon layer is used, the density of the metal-carbon composite structure in the composite sheet may be improved, and thermal conductivity, electromagnetic wave absorption, and electromagnetic wave shielding properties may be improved.

In addition, in the step of preparing the agglomerate, the size of the agglomerate can be controlled according to the specific gravity of the spray gas spraying the slurry into the chamber, thereby easily controlling the size of the metal-carbon composite structure. Can.

In addition, the aggregate used in the production of the metal-carbon composite structure can be controlled in shape by controlling the internal temperature of the chamber in which the fine particles are sprayed. Accordingly, the agglomerate can be made into a spherical shape, and the metal particles made from the agglomerate can be made into a spherical shape. Due to this, the metal structure and the metal-carbon composite structure can be easily produced, and the thermal conductivity, heat dissipation properties, electromagnetic wave absorption, and electromagnetic wave shielding properties of the composite sheet including the metal-carbon composite structure are improved. And the reliability of the manufacturing process can be improved.

Hereinafter, specific experimental examples of the metal-carbon composite structure according to the embodiment of the present invention described above, and the composite sheet produced using the same will be described.

Preparation of metal-carbon composite structure according to the embodiment

Fe ₂ O ₃ (D ₅₀ =1.0 μm) and NiO (D ₅₀ = 0.8 μm) of Kojundo chemical were prepared as metal oxides.

Circulating bead mill process was performed using 2,400 rpm, process time 1-15h, zirconia bead 3Φ, PCA (methanol). Specifically, a milling process was performed at a ratio of PCA (methanol):metal oxide=4:1 (wt%) to prepare fine particles.

The slurry containing fine particles was sprayed and dried using a spray-dryer to prepare Fe ₂ O ₃ and NiO aggregates. Specifically, agnehelic 30, tank temperature (30, 50, 70 ℃), injection pressure 0.8 psi, spray gas air, Ar was used.

Fe ₂ O ₃ and NiO aggregates were reduced in a hydrogen atmosphere. Specifically, the hydrogen reduction heat treatment process using a mass-produced large-capacity reduction reactor capable of reducing up to 5 kg under a heating condition of 5° C./min and a hydrogen gas atmosphere for 1 hour at 600° C. produces Fe ₂ O ₃ and NiO metal particles. Did. After reduction, it was collected in a glove box using prevention of reduction powder re-oxidation, and high purity hydrogen gas was used.

The metal particles in which Fe ₂ O ₃ and NiO agglomerates have been reduced are flattened to prepare a metal structure. Specifically, 200 rpm, Zrconia bead 3 Φ, the metal particles: bead weight ratio = 1: 5 conditions, using the Attrition mill, was performed the laceration process.

The metal structure was heat treated to remove the stress inside the metal structure. Specifically, the heat treatment was performed for 1 hour in a hydrogen gas atmosphere in a furnace, at a temperature of 5°C/min.

A carbon source mixed with Saccharouse (D(+)-Sucrose): DI water = 4: 9 was prepared and mixed with the heat-treated metal structure. Thereafter, the metal was coated with a carbon layer coated on the surface by drying at 100°C for 24 hours, primary heat treatment at 250°C for 8 hours, secondary heat treatment at 900°C for 4 hours, and classification with an 80 mesh standard mesh. A metal-carbon composite structure including the structure was prepared.

Composite sheet production according to the embodiment

The metal-carbon composite structure prepared according to the above-described embodiment was wetted in a solvent in which MEK and toluene were mixed in a 5:5 ratio, and the metal-carbon composite structure 86.3 wt% and a rubber binder 13.7 wt% were plantary mixers. The mixture was mixed at 1000 rpm for 30 minutes. Then, defoaming at 30 rpm for 20 minutes at 1 bar, and molded into a sheet using a comma coater to prepare a composite sheet according to an embodiment of the present invention.

3 is an XRD analysis result of Fe ₂ O ₃ and NiO used in the manufacture of a composite sheet according to an embodiment of the present invention.

Referring to FIG. 3, it can be confirmed that there are no impurities in the Fe ₂ O ₃ and NiO nano powders after the 10 hour milling process was performed.

4 is an SEM photograph of Fe ₂ O ₃ and NiO aggregates used in the manufacture of a composite sheet according to an embodiment of the present invention.

4, FIGS. 4(a) to 6(c) are SEM photographs of Fe ₂ O ₃ and NiO aggregates when the temperature in the chamber is 30° C., 50° C., and 70° C., respectively. , As a method of controlling the temperature inside the chamber, it can be confirmed that the shape of the aggregate can be controlled. Specifically, it can be confirmed that controlling the temperature inside the chamber to less than 50°C is an effective method for producing aggregates in a spherical shape.

5 is an XRD result graph of metal particles used in the manufacture of a composite sheet according to an embodiment of the present invention.

Referring to FIG. 5, XRD data of metal particles prepared according to an embodiment of the present invention was analyzed. As a result of the analysis, the Fe-Ni alloy phase, specifically, Fe (50wt%)-Ni (50wt%) It can be confirmed that metal particles comprising a permalloy alloy were formed.

6 is an SEM photograph of a metal structure used in the manufacture of a composite sheet according to an embodiment of the present invention.

Referring to FIG. 6, the flaking time of metal particles according to an embodiment of the present invention was adjusted to 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, and 12 hours. 6(a) to 6(f) are SEM photographs of Fe ₂ O ₃ and NiO flakes, respectively, for 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, and 12 hours of laceration time. .

As can be seen in Figure 6, it can be seen that as the milling time increases, the aspect ratio of the flaky aggregates increases and the thickness decreases. In particular, when performing the laceration process for more than 12 hours, the thickness becomes thinner, but the aspect ratio decreases, and it can be seen that the amount of fine powder increases. In addition, when the laceration process is performed for 10 hours, the aspect ratio is 20:1. You can see the biggest.

7 is an SEM photograph of a metal structure and commercial permalloy flakes used in the manufacture of a composite sheet according to an embodiment of the present invention.

Referring to FIG. 7, FIG. 7(a) is a SEM photograph taken after flaking a commercial permalloy to produce flakes, and FIG. 7(b) is a SEM of a metal structure manufactured according to an embodiment of the present invention It is a picture.

In addition, the operation of the commercial permalloy and the operation of the metal structure prepared from agglomerates according to an embodiment of the present invention were compared as shown in <Table 1> below.

division Flake
All granularity Flake
aspect ratio Flake
thickness Same conditions
Process time Commercial permalloy 5~20㎛ powder 20: 1 0.8㎛ 16hr Example 20~50nm Aggregation 5~20㎛ Aggregate 20: 1 0.8㎛ 10hr

Compared with a commercial permalloy, according to an embodiment of the present invention, it can be confirmed that the working time of the nanopowder aggregate Flake is only 10 hours, and a process time of about 38% can be saved.

8 is a SEM photograph of the metal structure used in the production of the composite sheet according to an embodiment of the present invention according to the heat treatment process temperature.

Referring to FIG. 8, heat treatment was performed at 600° C., 700° C., 800° C., and 900° C. for 1 hour to remove internal stress for a metal structure manufactured according to an embodiment of the present invention, and SEM photographs were taken. Specifically, FIGS. 8(a) to 8(d) are SEM photographs of heat treatment at 600°C, 700°C, 800°C, and 900°C, respectively.

As can be seen in Figure 8, as the heat treatment temperature increases, the internal stress is removed, and accordingly, local bonding occurs, and it can be seen that the powder shape is recovered and grown into particles. In particular, when heat-treated at 900 ℃, it can be seen that the local bonding occurs significantly significantly.

9 is a graph measuring magnetization and coercive forces of Fe ₂ O ₃ and NiO aggregates, metal structures, and heat-treated metal structures according to an embodiment of the present invention.

9, Fe ₂ O ₃ and NiO aggregates (as reduced), metal structures (as flake), and heat-treated metal structures (as annealed at 600°C, 700°C, 800) prepared according to an embodiment of the present invention The moment/mass for the magnetic field of ℃, 900℃) was measured using a vibrating sample magnetometer (VSM).

It can be seen that the Fe ₂ O ₃ and NiO aggregates and the saturation magnetization values of the metal structure are similar. In addition, the coercive force of the Fe ₂ O ₃ and NiO agglomerates is -75Oe, and the coercive force of the metal structure is -96Oe, which confirms that the coercive force is increased due to an increase in magnetic anisotropy. In addition, it can be seen that as the heat treatment temperature increases after the flaking, the coercive force gradually decreases due to particle growth and internal stress reduction.

division Aggregate Metal structure Heat treatment temperature () Commercial permalloy flakes 600 700 800 900 Coercive force (Oe) 75 96 57 48 37 30 30.9

10 is a Raman analysis result of a metal-carbon composite structure prepared according to an embodiment of the present invention.

Referring to FIG. 10, Raman analysis of a metal-carbon composite structure prepared according to an embodiment of the present invention was performed. 10(a) is a graph of Raman analysis results of a metal-carbon composite structure, and FIG. 10(b) is a graph of Raman analysis results of a metal-carbon composite structure washed using 35% hydrogen peroxide. As can be seen in Figure 10, it can be confirmed that the graphitic carbon formed by the formation of 2D band, G, D band peak. In particular, when the amorphous carbon was removed by washing with hydrogen peroxide, it can be confirmed that the formation of a graphitic carbon layer is clearly seen.

As described 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 by 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.

210: slurry tank
220: feed pump
230: compressor
240: chamber
250: exhaust pump
260: first obtaining tank
270: second obtaining tank

Claims (6)

Preparing a metal oxide;
Crushing the metal oxide to produce fine particles;
Mixing the fine particles in a solvent to prepare a slurry;
Separating and drying the slurry in a chamber to prepare agglomerates;
Obtaining and reducing the aggregates to produce metal particles;
Flattening the metal particles to produce a flattened metal structure; And
A method of manufacturing a metal-carbon composite structure comprising mixing the metal structure with a carbon source and heat-treating to produce a metal-carbon composite structure having a graphitic carbon layer coated on the surface of the metal structure. .
According to claim 1,
The step of preparing the aggregate,
Using a spray gas, spraying the slurry into the chamber,
Method of manufacturing a metal-carbon composite structure comprising controlling the size of the agglomerates according to the specific gravity of the spray gas.
According to claim 1,
A method of manufacturing a metal-carbon composite structure, further comprising the step of heat-treating the metal structure before mixing the metal structure with the carbon source, thereby removing the internal stress of the flattened metal structure.
According to claim 1,
The carbon source is a method of manufacturing a metal-carbon composite structure comprising sucrose.
Preparing a metal-carbon composite structure according to claim 1; And
A method of manufacturing a composite sheet comprising mixing the metal-carbon composite structure with a binder to produce a composite sheet.
The method of claim 5,
The metal structure is a method of manufacturing a composite sheet comprising an alloy of iron and nickel.

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