KR20190049255A - Method for manufacturing metallic structure with improved thermal resistance and metallic catalyst module using same - Google Patents

Abstract

The present invention relates to a method for manufacturing a metallic structure and a metallic catalyst module using the same, wherein the method comprises the following steps of: (a) preparing a powder mixture comprising metal powder and halide powder; (b) preparing a substrate comprising iron (Fe); (c) contacting the powder mixture with the substrate to be heated; (d) forming an intermetallic compound layer in an upper portion of the substrate; (e) forming an uneven structure including the metal powder on the intermetallic compound layer; and (f) heat-treating the substrate.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a method of manufacturing a metal structure having improved heat resistance and a metal catalyst module using the metal structure,

The present invention relates to a method of manufacturing a metal structure and a metal catalyst module using the same. More particularly, the present invention relates to a method of manufacturing a metal structure having a concave-convex structure including an intermetallic compound layer and a metal powder on a substrate including stainless steel and having excellent heat resistance characteristics through heat treatment, .

A metal catalyst module may be prepared by attaching a porous support layer and an active catalyst component on the surface of a metal structure such as a metal plate or a metal mesh. Such a metal catalyst module can increase the surface area per unit volume because it can use a thin metal having a high thermal conductivity and a fast temperature response characteristic as compared with a honeycomb reactor using a conventional ceramic structure. In addition, the pressure drop of the metal catalyst module can be reduced, and the processability is improved, so that it is easier to manufacture, and the durability is improved due to high mechanical strength.

When a metal structure is coated with a porous support layer and a catalyst and the catalyst is applied to a catalytic reactor operating at a high temperature, a difference in thermal expansion coefficient between the metal and the porous ceramic support is large, so that the porous support layer is easily peeled off. In order to solve such a problem, a method of forming irregularities on the surface of a metal structure and coating a porous carrier layer thereon has been studied.

On the other hand, in order to use a metal at a high temperature of 700 ° C or more, the metal itself must have a heat-resistant property. At this time, a typical alloy having heat resistance characteristics is Fe-Cr-Al alloy. The Fe-Cr-Al alloy contains 15 to 25% by weight of chromium (Cr), and 3 to 8% by weight of aluminum (Al) and silicon (Si). A small amount of yttrium (Y) or zirconium (Zr) may be added to improve the heat resistance. When Fe-Cr-Al alloy is heated in a high-temperature atmosphere, an alumina layer is formed on the surface to have a heat-resistant property. For this reason, a Fe-Cr-Al alloy may be used as a raw material of the high-temperature catalytic active plate.

Fe-Cr-Al powder was sprinkled on the surface of the iron (Fe) -chromium (Cr) -Al alloy (Fe-Cr-Al) here by a porous gamma-alumina (γ-alumina, γ-Al 2 O 3) wash coating (Wash coating) to prepare a catalytically active plate. It has been reported that porous activated gamma alumina can be durably durable even when the thermal activation test is repeated 1000 times at room temperature to 700 ° C (Korean Patent No. 10-1305451).

Generally, when a powder having a size of several hundreds of micrometers or less is supplied to the surface of the plate, there arises a problem that the powder easily falls off the plate surface when the plate is tilted during transportation or handling. In this case, unevenness is not uniformly formed on the surface of the plate. In addition, when it is desired to form concavities and convexities on a wire having a diameter of several hundreds of micrometers or less, it is considered that it is not easy to adhere the metal powder sprayed on the surface of the wire for forming the concavo-convex to the surface thereof.

In addition, since Fe-Cr-Al alloy is added with aluminum (Al) in an amount of more than several percent by weight relative to general stainless steel, it is difficult to control the melting process, and workability at high temperature and room temperature is poor, There is a disadvantage in that a plate material having a thickness of less than a meter (占 퐉) or a wire material having a diameter of several hundreds of micrometers (占 퐉) or less is several times more expensive than a stainless steel plate.

In addition, the commercially available stainless steel is inexpensive as compared with Fe-Cr-Al alloy, but has a high heat resistance and is difficult to use directly as a metal support for a high temperature catalyst module.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a method of manufacturing a semiconductor device, which comprises forming an intermetallic compound layer on a substrate including stainless steel, It is an object of the present invention to produce an excellent metal structure.

In addition, the present invention provides a catalyst module including the metal structure, which improves the adhesion force so that the porous carrier layer is not easily separated by the concavo-convex structure, and provides the heat resistant property that the surface of the catalyst module does not change even in a rapid heat treatment environment .

However, these problems are exemplary and do not limit the scope of the present invention.

According to an aspect of the present invention, there is provided a method of manufacturing a powder mixture comprising: (a) preparing a powder mixture including a metal powder and a halide powder; (b) preparing a substrate comprising iron (Fe); (c) contacting and heating the powder mixture and the substrate; (d) forming an intermetallic compound layer on the substrate; (e) forming an uneven structure including the metal powder on the intermetallic compound layer; And (f) heat treating the substrate.

According to an embodiment of the present invention, the metal powder may include an iron (Fe) -aluminum (Al) alloy powder or a chromium (Cr) -aluminum (Al) alloy powder.

According to an embodiment of the present invention, the amount of the aluminum (Al) alloy may be 45 to 55 wt% and the balance of the iron (Fe) may be constituted of the iron (Fe) -Al alloy.

According to an embodiment of the present invention, the chromium (Cr) -aluminum (Al) alloy powder may comprise 45 to 55% by weight of the aluminum (Al) and the balance of the chromium (Cr).

According to an embodiment of the present invention, in the step (c), the substrate and the powder mixture may be contacted by deepening the substrate with the powder mixture.

Further, according to one embodiment of the invention, the halide (Halide), the lithium chloride (LiCl), sodium chloride, alkali metal chlorides, calcium chloride, such as (NaCl), potassium chloride (KCl) (CaCl _2), barium chloride (BaCl ₂ ), ammonium chloride (NH ₄ Cl), sodium fluoride (NaF), potassium fluoride (KF), lithium fluoride (LiF), magnesium fluoride (MgF _2), calcium fluoride (CaF _2), barium fluoride (BaF ₂₎ and hydrofluoric (NH ₄ F), sodium iodide (NaI), potassium iodide (KI), lithium iodide (LiI), magnesium iodide (MgI ₂ ), calcium iodide (CaI ₂ ), barium iodide (BaI ₂ ) and ammonium iodide ₄ I). ≪ / RTI >

Also, according to an embodiment of the present invention, the powder mixture may comprise the remainder of the metal powder in an amount of 0.5 to 3% by weight of the halide powder.

Further, according to an embodiment of the present invention, in the step (c), the heating may be performed at 700 ° C to 1000 ° C for 4 hours to 36 hours.

According to an embodiment of the present invention, in the step (d), the metal powder reacts with the halide powder to form an aluminum halide, and the metal-halide reacts with the substrate, And forming the intermetallic compound layer on the substrate.

In addition, according to an embodiment of the present invention, the intermetallic compound layer may include aluminide.

According to an embodiment of the present invention, the step (e) may include forming the concavo-convex structure by bonding the intermetallic compound layer with the metal powder.

Further, according to an embodiment of the present invention, in the step (f), the heating may be performed at 700 ° C to 1000 ° C for 10 hours to 36 hours.

According to an embodiment of the present invention, in the step (f), the heating temperature and the heating time may satisfy the following expression (1).

[Formula 1]

exp (-234,000 / (R * 1273))] / [exp (-234,000 / (R * T))] (1/400) * (d) ² .

D is the size of the metal powder (10 ≤ d ≤ 106, in units of ㎛), R = 8.314 J / (mol * K), where h is the heating time in hours, T is the heating temperature in K, ))

According to an embodiment of the present invention, in the step (f), the intermetallic compound layer may be removed and a concave-convex structure may be formed on the substrate.

According to an embodiment of the present invention, in the step (f), the intermetallic compound layer may be solid solution and diffused into the substrate by heat treatment.

According to an embodiment of the present invention, the step (f) may be performed in an inert gas or a reducing gas atmosphere.

According to an aspect of the present invention, there is provided a metal catalyst module including a metal structure.

According to one embodiment of the present invention as described above, an intermetallic compound layer is formed on a substrate including stainless steel, a concavo-convex structure including metal powder is formed, and a metal structure having excellent heat- have.

According to the present invention, it is possible to manufacture a catalyst module including the metal structure, to improve the adhesion force so that the porous carrier layer can not easily be separated by the concavo-convex structure, and to improve the heat resistance characteristic that the surface of the catalyst module does not change even in a rapid heat treatment environment .

Of course, the scope of the present invention is not limited by these effects.

1 is a schematic view showing a manufacturing method of a metal catalyst module in which a conventional uneven structure is formed.
2 is a flowchart illustrating a method of manufacturing a metal structure according to an embodiment of the present invention.
3 is a schematic view showing a manufacturing method of a metal structure according to an embodiment of the present invention.
4 is a cross-sectional view of a metal structure in which an intermetallic compound layer is formed before heat treatment according to a comparative example of the present invention.
5 is a cross-sectional view of a metal structure according to an embodiment of the present invention.
6 is a graph showing a change in weight of a SUS430 substrate having a concavo-convex structure according to the particle size of an Fe-50 weight% Al alloy powder according to an experimental example of the present invention.
7 is a SEM photograph showing a surface of a SUS430 substrate having a concavo-convex structure according to the particle size of an Fe-50 weight% Al alloy powder according to an experimental example of the present invention.
8 is a metal catalyst module including a metal structure according to an embodiment of the present invention.
9 is an optical microscope photograph showing a cross-section of a metal structure having a concave-convex structure of an alumina layer and an Fe-50 weight% Al alloy powder and a porous carrier layer on an SUS430 substrate according to a comparative example of the present invention.
FIG. 10 is a graph showing the results of a comparison between a concavo-convex structure of an Fe-50 weight% Al alloy powder and an optical microscope showing a cross section of a metal structure forming a porous carrier layer, wherein an aluminide layer is removed on an SUS430 substrate according to an experimental example of the present invention It is a photograph.
11 is a graph of a thermal history test for evaluating the heat resistance characteristics of a metal catalyst module according to an experimental example of the present invention.
12 is a graph showing a correlation between the size of the Fe-50 weight% Al alloy powder and the heat treatment time for removing the intermetallic compound layer according to an experimental example of the present invention.
13 is a SEM photograph showing the surface of the metal catalyst module after evaluating the heat resistance characteristics according to one example of the present invention and one comparative example.

The following detailed description of the invention refers to the accompanying drawings, which illustrate, by way of illustration, specific embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. It should be understood that the various embodiments of the present invention are different, but need not be mutually exclusive. For example, certain features, structures, and characteristics described herein may be implemented in other embodiments without departing from the spirit and scope of the invention in connection with an embodiment. It is also to be understood that the position or arrangement of the individual components within each disclosed embodiment may be varied without departing from the spirit and scope of the invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is to be limited only by the appended claims, along with the full scope of equivalents to which such claims are entitled, if properly explained. In the drawings, like reference numerals refer to the same or similar functions throughout the several views, and length and area, thickness, and the like may be exaggerated for convenience.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings, so that those skilled in the art can easily carry out the present invention.

METHOD FOR MANUFACTURING METAL STRUCTURES CONSTRUCTED

1 to 3, a method of manufacturing a metal structure having a concave-convex structure will be described.

1 is a schematic view showing a manufacturing method of a metal catalyst module in which a conventional uneven structure is formed.

1, in the case of a metal catalyst module having a conventional concavo-convex structure, a metal powder is brought into contact with an iron (Fe) -aluminum (Al) -chromium (Cr) Followed by heat treatment to produce a metal structure having a concavo-convex structure. However, in the step of bringing the metal powder into contact with the upper portion of the metal substrate, the metal powder is not uniformly dispersed in the upper portion of the metal substrate, and the metal powder is not in contact with the metal powder. In addition, since the Fe-Al-Cr based metal substrate having excellent heat resistance is very expensive, there is a problem that the conventional manufacturing method is not effective.

FIG. 2 is a flow chart showing a manufacturing method of a metal structure 1 according to an embodiment of the present invention, and FIG. 3 is a schematic view showing a manufacturing method of a metal structure 2 according to an embodiment of the present invention.

According to an embodiment of the present invention, a method of manufacturing a metal structure 2 includes the steps of: (a) preparing a powder mixture 300 including a metal powder 31 and a halide powder 32; a step (S20) of preparing a substrate 10 containing iron (Fe), (c) a step (S30) of contacting and heating the substrate 10 with the powder mixture 300, (d) (S40) forming an intermetallic compound layer 20 on the intermetallic compound layer 20, (e) forming an uneven structure 30 including the metal powder 31 on the intermetallic compound layer 20 (S50 And (f) heat treating the substrate 10 (S60).

First, step (S10) of preparing the powder mixture 200 comprising (a) the metal powder 31 and the halide powder 32 will be described.

The metal powder 31 is placed in the crucible F and the substrate 10 containing the iron (Fe) is immersed therein. Then, the metal powder 31 is held in an inert atmosphere and heated at a high temperature to remove the iron (Fe) The concave-convex structure 30 can be formed on the upper part. At this time, the contact between the metal powder 31 and the substrate 10 including iron (Fe) is important. In order to make contact by mutual diffusion, the heat treatment temperature should be as high as 1000 ° C or higher, and the holding time should be long. However, under the above conditions, the metal powders are sintered to each other, and it is not easy to separate the metal structure 2 with the metal powder 31 from the metal powder 31.

When the metal powder 31 is doped with a halide powder 32 in an amount of less than several percent by weight, another reaction takes place to facilitate bonding of the metal powder 31 to the substrate 10. Since the halide powder 32 is water-soluble, it can be dissolved and dissolved in water after the reaction. Therefore, the halide powder 32 can be easily handled in the separation step after the step.

According to an embodiment of the present invention, the metal powder 31 may include an iron (Fe) -aluminum (Al) alloy powder or a chromium (Cr) -aluminum (Al) alloy powder.

An alloy powder containing aluminum (Al) is used in the production of the metal structure 2 to form a concave-convex structure 30 on the top of the substrate 10, and aluminum (Al) or chromium (Cr) Thereby imparting heat resistance characteristics to the substrate 10 containing iron (Fe).

On the other hand, in the iron-aluminum alloy powder, the content of aluminum can be controlled depending on the size of the iron-aluminum alloy powder, the thickness of the substrate including iron (Fe), and the like.

According to an embodiment of the present invention, the iron (Fe) -Al alloy powder may contain 45 to 55% by weight of aluminum (Al), the balance of iron (Fe) The aluminum (Al) alloy powder may comprise the balance of aluminum (Al) in an amount of 45 to 55% by weight and chromium (Cr).

When the metal powder 31 is formed on the upper portion of the substrate 10, the weight of the metal structure 2 on which the concavoconvex structure 30 is formed can be increased if the size of the metal powder 31 is increased. At this time, the metal structure 1 having the concave-convex structure 30 formed on the basis of the increased weight and the weight ratio of iron (Fe) to aluminum (Al) or chromium (Cr) to aluminum (Al) It is possible to calculate the content of aluminum (Al) or chromium (Cr) contained in the film. The content of aluminum (Al) or chromium (Cr) may vary depending on the thickness of the substrate 10. Therefore, the iron-aluminum weight ratio or the chromium-aluminum weight ratio of the metal powder 31 and the thickness of the substrate 10 can be adjusted in order to control the heat resistance characteristics of the metal structure 2 having the uneven structure 30 formed thereon.

The powder mixture 300 may contain a halide compound 32. According to one embodiment of the present invention, the halide may include at least one of the group consisting of chloride, fluoride, and iodide. Chlorides include lithium chloride (LiCl), sodium chloride (NaCl), potassium chloride (KCl) alkali metal chlorides, calcium chloride (CaCl _2), barium chloride (BaCl ₂₎ an alkaline earth metal chlorides, ammonium chloride (NH ₄ Cl), such as such as And at least one of the groups may be included. A fluoride is a sodium fluoride (NaF), potassium fluoride (KF), lithium fluoride (LiF), magnesium fluoride (MgF _2), calcium fluoride (CaF _2), barium fluoride (BaF ₂₎ and ammonium fluoride (NH ₄ F) And at least one of the groups may be included. Iodide is sodium iodide (NaI), potassium iodide (KI), lithium iodide (LiI), magnesium iodide (MgI _2), calcium iodide (CaI _2), barium iodide (BaI ₂₎ and ammonium iodide (NH ₄ I) And the like.

According to an embodiment of the present invention, the powder mixture 300 may comprise 0.5 to 3% by weight of the halide powder 32 and the metal powder 31. If the amount of the halide powder 32 is less than 0.5% by weight, the rate of formation of the intermetallic compound layer 20 is slowed. If the amount of the halide powder 32 is more than 3% by weight, post-treatment of the metal structure having the concave- Therefore, the formation rate of the intermetallic compound layer 20 formed on the substrate 10 can be controlled and the content of the halide powder 32 can be adjusted for ease of post-treatment.

Next, step (S20) of preparing the substrate 10 containing (b) iron (Fe) can prepare the substrate 10 on which the concavo-convex structure is formed in the crucible F. 3 (a) and 3 (b), the substrate 10 can be vertically set in the crucible F, and at least one substrate 10 can be prepared at the same time.

The substrate 10 containing iron may be stainless steel SUS430 stainless steel. However, the present invention is not limited thereto. The SUS430 stainless steel contains 16 to 18% by weight of chromium (Cr) elements, and contains a few percent by weight aluminum (Al) element in the SUS430 substrate without change in shape, It is possible to manufacture a Fe-Cr-Al metal substrate having heat resistance.

Next, (c) contacting and heating the substrate 10 with the powder mixture 300 is performed by deepening the substrate 10 into the powder mixture 300 to form the powder mixture 300, (300). There has been a problem in uniform distribution of the metal powder and in contact with the metal powder. However, in the case of the present invention, since the substrate 10 is dipped and contacted so as to cover the powder mixture 300, the powder mixture 31 containing the substrate 10 on which the concave-convex structure 30 is formed and the metal powder 31 The metal powder 300 can be uniformly dispersed and the adhesion force of the metal powder 31 can be improved.

3 (a) and 3 (b), when the powder mixture 300 is prepared in the crucible F and the substrate 10 is covered with the powder mixture 300 in the crucible F, It is dipped. Therefore, since the powder mixture 300 is dispersed around the substrate 10, the metal powder 31 contained in the powder mixture 300 and the halide compound 32 uniformly contact the substrate 10 .

Meanwhile, according to one embodiment of the present invention, in the step (c), the heating may be performed at 700 ° C to 1000 ° C for 4 hours to 36 hours.

The reaction temperature of the metal structure (2) production process may be performed at 700 캜 to 1,000 캜. If the reaction temperature is higher than 1,000 ° C., the formation of the intermetallic compound layer 20 is advantageous, but the sintering between the metal powders 31 proceeds rapidly, which may result in difficulty in separating the substrate 10 after the reaction. If the reaction temperature is lower than 700 캜, it takes a long time to form the intermetallic compound layer 20, which is inefficient.

In addition, when the reaction temperature is high, the holding time can be shortened, and when the reaction temperature is low, the holding time can be increased to form the concave-convex structure 30 simultaneously with the formation of the intermetallic compound layer 20. The retention time can be performed for 4 hours to 36 hours. The holding time may vary depending on the reaction temperature. Preferably, the holding time may be 36 hours or less when the reaction temperature is 700 ° C, and 4 hours or less when the temperature is 1,000 ° C.

Next, (d) step (S40) of forming the intermetallic compound layer 20 on the substrate 10 will be described.

In one embodiment of the present invention, the step (d) comprises the steps of: reacting the metal powder 31 and the halide powder 32 to form a metal halide; And forming an intermetallic compound layer 20 on the substrate by reacting.

When the powder mixture 300 containing the substrate 10 containing iron and the metal powder 31 and the halide powder 32 is heated, a small amount of the halide powder 32 and the metal contained in the metal powder 31 Elements (e.g., aluminum (Al)) react to form metal-halide compounds, which migrate to the top of the substrate 10 in a gas phase. The metal-halide formed may react with the substrate 10 to form the intermetallic compound layer 20 on the substrate.

According to one embodiment of the present invention, the intermetallic compound layer 20 may include Aluminide. For example, the aluminide may include Fe-Al intermetallic compounds Fe ₃ Al, FeAl, FeAl ₂ , Fe ₂ Al ₅ , and the like.

When the metal powder 31 comprises an iron (Fe) -aluminum (Al) metal powder containing aluminum (Al) or a chromium (Cr) -aluminum (Al) metal powder and the halide powder 32 contains chloride , The chloride reacts with aluminum in the metal powder 31 by heating the crucible F to form an aluminum-chloride such as AlCl, AlCl ₂ , AlCl _3, or the like. The equilibrium vapor pressure of the aluminum-chloride on the surface of the metal powder 31 is higher than the surface of the substrate 10, so that the aluminum-chloride moves to the surface of the substrate 10 in a vapor state. The following reaction takes place on the surface of the substrate 10 and Al (s, l) is deposited on the surface of the substrate 10.

3AlCl (g) → 2Al (s , l) + AlCl 3 (g)

3AlCl ₂ (g)? Al (s, l) + 2AlCl ₃ (g)

On the other hand, the Fe-Al binary phase diagram shows that there is a large amount of stable aluminide compound, and the intermetallic compound layer 20 formed by reaction with aluminum (Al) deposited on the surface of the substrate 10 containing iron ) May comprise an Aluminide layer.

On the other hand, the thickness of the aluminide layer may preferably be 100 mu m or less. When the thickness of the aluminide layer is 100 mu m or more, the thermal expansion coefficient is different from that of the metal substrate 10 containing iron, cracks are generated in the aluminide layer having a high brittleness in the high temperature-normal temperature thermal history test, The phenomenon of desorption may occur. Therefore, it is necessary to control the heating time of the crucible F and the aluminum content of the metal powder 31 to adjust the thickness of the aluminide layer to 100 탆 or less.

Next, step (S50) of forming the concavo-convex structure 30 including the metal powder 31 on the intermetallic compound layer 20 is performed so that the intermetallic compound layer 20 bonds with the metal powder 31 Thereby forming the concave-convex structure 30.

The metal powder 31 present on the surface of the substrate 10 is bonded to each other by mutual diffusion at the contact portion to form the concavoconvex structure 30. [ The concavo-convex structure 30 can be formed by a method in which the metal powder 31 on the surface of the substrate 10 is held by the intermetallic compound layer 20 when the intermetallic compound layer 20 is formed.

When the heating and holding time of the crucible F has elapsed, the metal powder 31, which has been in contact with the surface of the substrate 10 while growing the intermetallic compound layer 20, bonds with the intermetallic compound layer 20, Can be formed.

The metal powder 31 can be bonded to the intermetallic compound layer 20 formed on the substrate 10. At this time, the bonding does not form a chemical bonding with the intermetallic compound layer 20 but forms a physical bonding. That is, when the crucible F is heated to form the intermetallic compound layer 20, the metal element (for example, iron (Fe), aluminum (Al), chromium ) Is physically attached and fixed to the element contained in the intermetallic compound layer 20. Stronger physical bonds can be formed by the intermetallic compound layer 20 than when the metal powder is brought into contact with the upper portion of the metal substrate and sintered in the conventional metal structure manufacturing method. Therefore, after the intermetallic compound layer 20 is formed, the irregular structure 30 is uniformly distributed by the metal powder 32 dispersed evenly in the metal structure 1, and the metal powder 31 is uniformly distributed It has an effect that it is combined with the compound layer 20 so that the adhesion strength of the concave-convex structure 30 is excellent and it is not easily torn away.

The powder mixture 300 remaining after separating the metal structure 2 having the concavoconvex structure 30 from the powder mixture 300 containing the metal powder 31 and the halide powder 32 is mixed with the halide powder 32, By the formation of the concavoconvex structure 30, a large portion is lost and most of the metal powder 31 constitutes the remainder. The metal powder 31 remains in a partially sintered state due to the reaction at a high temperature. It is possible to reuse the metal powder 31 by subjecting it to external force and crushing and sieving.

Next, (f) heat-treating the substrate (S60) may be included.

FIG. 4 is a cross-sectional view of a metal structure 1 in which an intermetallic compound layer 20 is formed before a heat treatment according to a comparative example of the present invention, and FIG. 5 is a cross-sectional view of a metal structure 2 according to an embodiment of the present invention. Sectional view.

the intermetallic compound layer 20 formed in the step (d) has a high brittleness and a thermal expansion coefficient different from that of the substrate 10 so that cracks are formed in the intermetallic compound layer 20 in an abrupt heat treatment environment, The phenomenon of desorption may occur. This is because when the catalyst module is manufactured using the metal structure 1 in which the intermetallic compound layer 20 is formed, the porous carrier layer is separated in an environment where the abrupt temperature changes, Means that the catalyst components formed on the surface of the catalyst module can be desorbed. Therefore, a heat treatment step is required to prevent the intermetallic compound layer 20 from cracking.

According to an embodiment of the present invention, in step (f), the step of removing the intermetallic compound layer 20 and forming a concave-convex structure on the substrate 10 may be included.

The intermetallic compound layer 20 needs to be removed by heat treatment in order to prevent the catalytic components from being separated from the surface of the catalyst module due to cracks in the intermetallic compound layer 20 in an abrupt temperature change environment. The metal powder 31 is also composed of an intermetallic compound layer 20 (Fe aluminide or Cr aluminide). The concentration of Al or Cr in the metal powder 31 and the intermetallic compound layer 20 is higher than that in the substrate 10 and the Fe concentration is lower in the substrate 10. [ Therefore, when the substrate 10 is held at a high temperature, the intermetallic compound layer 20 and the metal powder 31 can be removed through heat treatment because Al, Cr, and Fe are mutually diffused by a concentration gradient. At this time, the concavo-convex structure 30 formed on the intermetallic compound layer 20 can exist in the upper portion of the substrate 10 in a substantially unchanged state. That is, the intermetallic compound layer 20 capable of causing cracks in an abrupt temperature change environment is removed from the upper part of the substrate 10, and the metal structure 2 having the concave-convex structure 30 formed on the substrate 10 Can be manufactured. The metal structure 2 can prevent the formation of cracks due to the difference in the coefficient of thermal expansion and improve the heat resistance characteristics of the catalyst module under the abrupt temperature change condition.

According to an embodiment of the present invention, in step (f), the intermetallic compound layer 20 may be solid solution and diffused into the substrate 10 by heat treatment.

The heat treatment time for removing the intermetallic compound layer 20 may vary depending on the size of the metal powder 31 and the heat treatment temperature. The larger the size of the metal powder 31 used for forming the concave-convex structure 30, the longer the heat treatment time becomes, the lower the heat treatment temperature.

According to an embodiment of the present invention, in the step (f), the heating may be performed at 700 ° C to 1000 ° C for 10 hours to 36 hours. According to another embodiment, the step (f) Or in a reducing gas atmosphere. However, the embodiments of the present invention are not limited thereto.

 The size of the concave and convex structure 30 including the metal powder 31 may vary depending on the size of the metal powder 31 and the alloy content. Further, the thickness and the composition of the intermetallic compound layer 20 can be changed because an element contained in the metal powder 31 forms the intermetallic compound layer 20. [ Accordingly, in the heat treatment step S60, the heating temperature and the heating time may vary depending on the thickness and the composition of the intermetallic compound layer 20 in order to solidify and remove the intermetallic compound layer 20. [ As the size of the metal powder 31 increases, it may be necessary to heat the solute metal contained in the intermetallic compound layer 20 for a long time until it diffuses and permeates into the solvent metal. Therefore, the larger the size of the particles of the metal powder 31, the longer the heat treatment time and the temperature for removing the intermetallic compound layer 20 can be.

5, a metal structure 2 according to an embodiment of the present invention includes an intermetallic compound layer 20 formed on an upper surface of a substrate 10, The concavoconvex structure 30 can be formed on the upper portion of the substrate. The adhesion force with the porous carrier layer that can be coated on the substrate 10 can be improved through the concave and convex structure 30 and the cracks of the intermetallic compound layer 20 due to the difference in thermal expansion coefficient can be prevented, Can be improved.

Next, the metal structure 2 including the intermetallic compound layer 20, the metal structure 1 having the concave-convex structure 30 formed thereon and the intermetallic compound layer 20 removed and the concave-convex structure 30 being formed will be described .

Experimental Example . The intermetallic compound layer  And a metal structure having a concavo-convex structure formed therein

6 and 7, the metal structure 2 on which the intermetallic compound layer 20 is removed by using the Fe-50 weight% Al alloy powder and the SUS430 substrate and in which the concave-convex structure 30 is formed will be described.

In this experimental example, the substrate 10 may be stainless steel SUS430. However, the present invention is not limited to the examples. The SUS430 stainless steel contains 16 to 18% by weight of chromium (Cr) elements. When a few percent by weight aluminum (Al) element is added to the SUS430 substrate without changing its shape, the Fe- . ≪ / RTI >

The metal powder 31 contains Fe-50 weight% Al alloy powder in which aluminum (Al) is 50% by weight and iron (Fe) is the balance and the halide powder 32 is ammonium chloride (NH ₄ Cl) A powder mixture 200 is prepared by mixing 100 wt% of Fe-50 wt% of Al and 1 wt% of ammonium chloride (NH ₄ Cl). A SUS430 substrate having a thickness of 0.5 mm is dipped in a powder mixture 300 in a crucible F and reacted at 1,000 DEG C for 3 hours in an argon atmosphere to prepare a metal structure 2 having a concave-convex structure 30 formed thereon. At this time, the aluminum (Al) element contained in the Fe-50 weight% Al reacts with ammonium chloride (NH ₄ Cl) to form aluminum-chloride, and the aluminum- ) To form an aluminide layer.

On the other hand, the Fe-50 weight% Al alloy powder is a state in which two intermetallic compounds of FeAl ₂ and Fe ₂ Al ₅ are mixed. It is strong in brittleness and it is easy to make it into powder after it is made into ingot and crushed. Fe-50 weight% Al alloy powder can be used, but FeAl ₃ powder having a higher content of aluminum (Al) or FeAl alloy powder having a lower Al content can be used. In addition, Al-Cr alloy powder can be used to form concave and convex structures 30 by simultaneously adding Cr (Cr) and Al (Al). The content of chromium (Cr) in the Al-Cr alloy powder and the size of the Al-Cr alloy powder vary depending on the content of chromium (Cr) in the SUS430 substrate and the thickness of the SUS430 substrate. The composition and size of the Al-Cr alloy powder can be adjusted by changing the production conditions of the alloy powder, so that the content of chromium (Cr) in the Al-Cr alloy powder can be controlled.

6 is a graph showing the weight change of the SUS430 substrate 10 formed with the concave-convex structure 30 according to the particle size of the Fe-50 weight% Al alloy powder according to an experimental example of the present invention.

Referring to FIG. 6, it can be seen that as the size of the Fe-50 weight% Al alloy powder increases, the weight increase also increases. The weight increase range of the SUS430 substrate 10 is 4.37% to 8.95%. If the aluminum (Al) contained in the Fe-50 weight% Al alloy powder forming the concave and convex structure 30 is diffused and uniformly distributed throughout the SUS430 substrate 10 and the Fe-50 weight% Al alloy powder The aluminum (Al) content range of the metal structure 1 in which the concave-convex structure 30 is formed can be calculated to be 2.18% to 4.48%. When the thickness of the SUS430 substrate 10 is halved, the content of aluminum (Al) can be doubled when other experimental conditions are the same.

7 is a SEM photograph showing a surface of a SUS430 substrate 10 on which a concave-convex structure 30 is formed according to a particle size of an Fe-50 weight% Al alloy powder according to an experimental example of the present invention.

7 (a), 7 (b), 7 (c) and 7 (d) show the sizes of Fe-50 weight% Al alloy powders of 45 μm or less, 45 to 63 μm, 63 to 90 μm, The surface of the SUS430 substrate 10 on which the concave-convex structure 30 is formed. As the size of the Fe-50 weight% Al alloy powder is smaller, the density of the concave-convex structure 30 becomes larger, and it can be confirmed that the surface is in a very rough state. On the other hand, the larger the size of the Fe-50 weight% Al alloy powder is, the lower the density of the concave and convex structure 30 is, but the larger the size and depth of the concave and convex structure 30 is.

On the other hand, a process of heat treatment at a high temperature for a long period of time is required to remove the intermetallic compound layer 20. The higher the heat treatment temperature, the more advantageous it can be, but it can be in the temperature range of 1,000 ° C to 1,200 ° C, which is possible in a conventional electric furnace. In this experiment, the heat treatment temperature was 1,000 ° C. and the heat treatment was performed in an argon (Ar) atmosphere.

An intermetallic compound layer 20 containing alumina and an Fe-50 weight% Al alloy powder are formed on the substrate 10. The larger the size of the Fe-50 weight% Al alloy powder, the longer the heat treatment time for removing the intermetallic compound layer 20 is required. In order to derive an appropriate heat treatment time, a specimen of the metal structure 2 having the uneven structure 30 according to the size of the Fe-50 weight% Al alloy powder was prepared.

As shown in FIG. 7, Fe-50 weight% Al alloy powders of 45 탆 or less, 45 to 63 탆, 63 to 90 탆, and 90 to 106 탆 were used for the size of the metal powder 31, 30) were fabricated and annealed at 1000 ℃ for 10 hours to prepare specimens.

Fe-50 weight% Al alloy powders of 45 탆 or less, 45 to 63 탆, 63 to 90 탆 and 90 to 106 탆, respectively, were used for the size of the metal powder, and the specimens were heat treated at 1,000 캜 for 24 hours to prepare specimens 50 wt% Al alloy powder having a size of 90 to 106 mu m as the metal powder 31 was heat-treated at 1,000 DEG C for 36 hours to prepare a specimen.

Metal catalyst module and heat resistance evaluation

Next, the metal catalyst module 3 will be described with reference to Figs. 8 to 10. Fig.

8 is a cross-sectional view of a metal catalyst module 3 including a metal structure 2, according to an embodiment of the present invention.

According to an embodiment of the present invention, the metal catalyst module 3 may include a metal structure 2 on which a concave-convex structure 30 is formed.

5 and 8, the metal catalyst module 3 may include a metal structure 2 on which a concave-convex structure 30 is formed on a metal substrate 10. The metal catalyst module 3 may have a porous carrier layer 40 formed on the metal structure 2 and a catalytically active component 50 formed on the porous carrier layer 40.

A step of forming a concave-convex structure 30 on the surface of the metal structure 2 and coating the porous carrier layer 40 is performed. The porous carrier layer 40 may be formed of a material such as gamma alumina (Al ₂ O ₃ ), silica (SiO ₂ ), titania (TiO ₂ ), zeolite, ceria (Ce ₂ O ₃ ), magnesia (MgO) V ₂ O ₅ , CoO x, FeO x, WO ₃ , molybdenum oxide MoO ₃ , antimony oxide SbO ₂ and rare earth oxides Sc, Oxides), and the like.

To coat the porous carrier layer 40 A method of wash coating the porous carrier particles can be used. The particle size, slurry concentration and solvent of the porous carrier component used in the wash coating can be performed according to conventional processes. In order to improve the coating effect of the porous carrier layer 40, the porous carrier slurry may contain a surfactant, an auxiliary agent such as a binder, and the like.

On the other hand, when the porous carrier layer 40 is coated, the coating layer of the porous carrier layer 40 is densely coated on the surface of the metal structure 2 on which the concave and convex structure 30 is formed. Preferably, a porous carrier layer 40 having a thickness in the range of 10 탆 to 100 탆 may be formed on the surface of the metal structure 2.

Next, the metal structure 2 on which the porous carrier layer 40 is formed is heated to remove moisture, binder, and other components contained in the porous carrier layer 40. In this process, the porous carrier component is partially sintered and adhered to the surface of the metal structure 2, and the porous carrier layer 40 is fractured to form a porous carrier layer 40 having a structure cracked at intervals of several micrometers to several hundreds of micrometers. . At this time, if the heating temperature is too high, sintering occurs in the porous carrier layer 40 itself and the specific surface area of the porous carrier layer 40 is lowered. Therefore, the heating is preferably performed at a temperature of 900 ° C or lower. If the temperature is too low, it is difficult to remove additives such as moisture and binder, and therefore, it is preferably heated at a temperature of 150 캜 or higher.

 9 is an optical microscope photograph showing a cross section of a metal structure having a concave-convex structure of an aluminide layer and an Fe-50 weight% Al alloy powder and a porous carrier layer on a SUS430 metal substrate according to a comparative example of the present invention .

9, it can be seen that the metal powder 31 is fixed to the intermetallic compound layer 20 to form the concavo-convex structure 30, and the porous carrier layer 40 including the porous gamma alumina is wash coated have. In order to form the concave-convex structure 30, an Fe-50 weight% Al alloy powder of 90 to 106 mu m in size was used.

10, the alumina layer formed on the upper part of the SUS430 substrate according to an experimental example of the present invention is removed, and the concave-convex structure 30 of the Fe-50 weight% Al alloy powder and the porous carrier layer 40 are formed Fig. 2 is an optical microscope photograph showing a cross section of the metal structure 2 having a light emitting layer.

10, it can be seen that the porous carrier layer 40 containing porous gamma alumina is formed on the metal structure 2 on which the intermetallic compound layer 20 is removed and the concavo-convex structure 30 is formed. 9, the intermetallic compound layer 20 formed on the upper portion of the substrate 10 is removed, and the shape of the metal powder 31 is partially changed by diffusion. However, the irregular structure 30 remains intact . In order to form the concavoconvex structure 30, an Fe-50 weight% Al alloy powder having a size of 45 to 63 탆 was used and in an argon (Ar) atmosphere at 1000 캜 for 10 hours to remove the intermetallic compound layer 20 To prepare a metal structure (2).

Since the porous carrier layer 40 formed on the upper part of the metal structure 2 manufactured through the above process is attached between the concave and convex structures 30, the adhesion force is firmly maintained even after the porous structure is exposed to a high- Thereby providing a favorable environment in which the catalytically active component is supported.

After the porous carrier layer 40 is formed, the metal catalyst module 3 is manufactured by carrying out the process of supporting the catalytically active component 50. The catalytically active component 50 carried on the porous carrier layer 40 may be a commonly used metal catalyst component 50 such as a noble metal or a transition element. The metal structure 2 in which the porous carrier layer 40 is formed is immersed in a solution in which the catalytically active component 50 is dissolved to support the catalytically active component 50 in the porous carrier layer 40 so that the solution penetrates into the porous structure The metal catalyst particles 50 may be introduced into the porous structure by immersing the metal structure 2 having the porous support layer 40 formed on the slurry in which the catalytically active component 50 is dispersed. The metal catalyst module 3 may be manufactured by forming the porous carrier layer 40 in which the catalytically active component 50 is uniformly distributed and coating it on the metal structure 2 on which the concavo-convex structure 30 is formed.

Next, the evaluation of the heat resistance characteristics of the metal catalyst module 3 will be described with reference to Figs. 11 to 13. Fig.

The phenomenon that the porous carrier layer 40 is detached from the metal structure 2 when the metal catalyst module 3 including the metal structure 2 is repeatedly exposed to a high temperature use environment is caused by a difference in thermal deformation coefficient . The thermal expansion coefficients of various alloys usable as the substrate 10 of the metal structure 2 are as follows.

(Al) alloy 22 to 24 X 10 ^-6 K ^-1 , a copper alloy 17 to 19 X 10 ^-6 K ^-1 , a magnesium alloy 26 to 27 X 10 ^-6 K ^-1 , a nickel (Ni) alloy 12 to 14 X 10 ^-6 K ^-1 , titanium (Ti) alloy 8 to 10 × 10 ^-6 K ^-1 , zirconium (Zr) alloy 5 to ⁶ × 10 ^-6 K ^-1 , carbon steel / low alloy steel / high alloy steel 10 to ¹⁴ × 10 ^-6 K ^-1 , austenitic high alloy steels 14 to 18X10 ^-6 K ^-1 .

On the other hand, the thermal expansion coefficient of the porous carrier layer 40 coated on the metal structure 2 made of one or more of the above alloys is as follows.

Zirconium oxide _{^{(ZrO 2) 15.3X10 -6 K -1}} , Mullite 5.3X10 -6 K -1, aluminum _{(Al 2 O 3) 8 ~} 9.6X10 -6 K -1, cerium (CeO ₂₎ 13X10 ^-6 oxide K ^-1 , titanium oxide (TiO ₂ ) 9.4X10 ^-6 K ^-1 .

For example, aluminum (Al ₂ O ₃₎ oxide coating layer on the porous carrier SUS430 of ferritic stainless steel usable at high temperatures, the thermal expansion coefficient of SUS430 is 12X10 ^-6 K ^- a ¹ degree, Al ₂ O ₃ 8 to 9.6X10 ^-6 K ^-1 . When a temperature difference occurs in the SUS430 substrate coated with aluminum oxide, the thermal stress due to the difference in thermal expansion coefficient of the two materials is concentrated on the interface between the aluminum oxide and the SUS430 substrate. Since the porous carrier layer having a small thermal deformation coefficient has less volume change than the volume change of the metal structure having a large thermal deformation coefficient, when a sudden change in the external temperature occurs, thermal stress builds up in the interface between the two materials, . That is, when the thermal stress accumulated at the interface becomes larger than the bonding force between the two materials, peeling occurs.

In order to evaluate the heat resistance characteristics of the metal catalyst module 3 having the porous carrier layer 40 formed thereon, the following test was carried out.

11 is a graph of a thermal history test for evaluating the heat resistance characteristics of the metal catalyst module 3 according to an experimental example of the present invention.

The porous carrier layer 40 was formed on the metal structure 1 without removing the intermetallic compound layer 20 to prepare a metal catalyst module specimen. The specimen was placed at the central portion of the furnace heated to 700 ° C, After holding it for a few minutes, take it out and put it in water kept at normal temperature and quench it. The temperature of the metal catalyst module specimen is increased to 700 DEG C after 5 minutes. The specimens quenched in water are then dried and the change in weight measured. The heat history test for evaluating the heat resistance characteristics was repeated 10 times, and the weight change was measured every time, and the results are summarized in the following [Table 1].

Table 1 is a table showing the results of thermal history test according to the sizes of the Fe-50w% Al alloy powder of the metal catalyst module specimen using the metal structure 1 in which the intermetallic compound layer 20 is formed. The results were summarized by the size of the Fe-50 weight% Al alloy powder used for forming the concave-convex structure 30. Referring to Table 1, it can be seen that as the size of the Fe-50w% Al alloy powder increases, the porous carrier layer 40 containing gamma-alumina coated by the heat resistance evaluation test more easily peels off Able to know.

[Table 1]

(*) The numbers in the above table represent the weight loss percentage of the gamma alumina porous carrier layer 40.

The delamination of the gamma alumina porous carrier layer 40 may be caused by the difference in thermal expansion coefficient between the gamma alumina porous carrier layer 40 and the substrate 10 but may be caused by the difference in thermal expansion coefficient between the substrate 10 and the intermetallic compound layer 20. [ It is also possible to peel off the intermetallic compound layer 20 by tearing. Since the intermetallic compound layer 20 containing aluminide has a thermal expansion coefficient larger than the thermal expansion coefficient of the SUS430 substrate, cracks are generated in the intermetallic compound layer 20 having a high brittleness, A phenomenon may occur in which a chip is detached from the interface between the substrate and the substrate.

In order to confirm this, a metal structure 2 specimen in which the intermetallic compound layer 20 was removed was prepared in the same manner as in the above Experimental Example, and the gamma alumina porous carrier layer 40 was wash coated to prepare a metal catalyst module 3) Prepare the specimen. A heat resistance characteristic evaluation test of the same method is performed on the metal catalyst module (3) prepared by the above method. Table 2 is a table showing the test results of heat resistance characteristics evaluation of the metal catalyst module 3 specimen according to one experimental example of the present invention.

[Table 2]

(*) The numbers in the above table represent the weight loss percentage of the gamma alumina porous carrier layer 40.

Referring to [Table 2], it can be seen that the weight loss percentage of the gamma alumina porous carrier layer 40 is reduced in the thermal history test due to the removal of the intermetallic compound layer 20. Particularly, when the size of the Fe-50w% Al alloy powder is 63 μm or less, even if the heat treatment is performed for only 10 hours at 1,000 ° C., the separation of the porous carrier layer 40 does not occur at all. If the heat treatment is performed at 1000 ° C. for 36 hours , And the size of the Fe-50w% Al alloy powder was 106 탆 or less, the porous carrier layer 40 did not separate. This is because the intermetallic compound layer 20 is removed by the heat treatment to reduce the occurrence of cracks that can be formed on the surface of the intermetallic compound layer 20 in an abrupt temperature change environment to reduce the desorption of the porous carrier layer 40 .

The time required to remove the intermetallic compound layer 20 by high temperature diffusion increases as the thickness of the intermetallic compound layer 20 or the size of the metal powder 31 increases. Since the intermetallic compound layer 20 is removed through diffusion in the solid phase, the heat treatment time is proportional to the square of the size (占 퐉) of the metal powder 31 if the temperature is the same.

12 is a graph showing a correlation between the size of the Fe-50 weight% Al alloy powder and the heat treatment time for removing the intermetallic compound layer 20 according to an experimental example of the present invention. The relationship between the heat treatment time at 1,000 占 폚 at which the thermal history test was passed ten times and the size of the Fe-50 weight% Al alloy powder used for forming the concave-convex structure (30) are shown.

Considering the principle that the diffusion distance of the intermetallic compound is proportional to the square root of the time, the intermetallic compound layer 20 is removed by setting the heat treatment condition at 1,000 ° C. under the condition corresponding to the region to the right of the straight line in FIG. It can be seen that the conditions are appropriate for the following. The slope is measured in 20 (㎛ / time ^{of 2).} Therefore, the heat treatment time for removing the intermetallic compound layer 20 satisfies the following expression (1).

[Formula 1]

Heat treatment time (hours) ≥ (1/400) * (size of metal powder (탆)) ² .

As the heat treatment temperature increases, the heat treatment time will decrease. As the temperature decreases, the heat treatment time will increase more. This can be estimated from the activation energy value of the Fe-Al binary interdiffusion coefficient, considering that the temperature dependence of the solid phase diffusion follows the Arrhenius equation. When the Al content in the Fe-Al binary system is in the range of 0 to 52 wt%, the activation energy of the mutual diffusion coefficient is 234,000 J / mol. In consideration of this, the temperature variable is added to the above equation, which can be expressed by the following equation (2).

[Formula 2]

exp (-234,000 / (R * 1273))] / [exp (-234,000 / (R * T))] (1/400) * (d) ² .

D is the size of the metal powder (10? D? 106, unit is μm), R is 8.314 J / (mol * K)),

Here, 'R' is a gas constant whose value is 8.314 J / (mol * K), and 'T' represents the heating temperature (K). The size of the metal powder 31 may be 10 [mu] m to 106 [mu] m. Metal powders having a size larger than 10 탆 are used because they are difficult to produce by conventional methods. When the heat treatment temperature is increased from 1,000 ° C. to 1,100 ° C., the heat treatment time is reduced by about 5 times.

13 (a) shows the surface after the heat resistance evaluation test of the metal catalyst module using the metal structure 1 in which the intermetallic compound layer 20 according to the comparative example of the present invention is formed, and FIG. 13 (b) Shows the surface after the heat resistance property evaluation test of the metal catalyst module 3 using the metal builder (2) according to one embodiment of the present invention.

Referring to FIG. 13 (a), it can be seen that the gamma alumina porous carrier layer 40, which appears as a dark portion, is partly removed by the thermal history test and has a rough surface with no smooth surface. On the other hand, referring to FIG. 13 (b), it can be seen that the gamma alumina porous carrier layer 40 is firmly adhered together with the concavo-convex structure 30 without being removed.

Therefore, the present invention is characterized in that the metal catalyst module 3 including the metal structure 2 is formed by forming the concave-convex structure 30 on the surface of the metal structure 2 and removing the intermetallic compound layer 20 by heat treatment, It is possible to improve the adhesion of the porous carrier layer 40 formed on the upper portion of the structure 2 and to improve the heat resistance characteristic so that the change of the surface is small even in a sudden temperature change environment.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be taken in conjunction with the present invention. Variations and changes are possible. Such variations and modifications are to be considered as falling within the scope of the invention and the appended claims.

1: Metal structure in which an intermetallic compound layer is formed
2: metal structure
3: Metal catalyst module
10: substrate
20: intermetallic compound layer
30: concave and convex structure
31: metal powder
32: halide powder
40: Porous carrier layer
50: Catalytically active component
300: powder mixture
F: Crucible

Claims (17)

(a) preparing a powder mixture comprising a metal powder and a halide powder;
(b) preparing a substrate comprising iron (Fe);
(c) contacting and heating the powder mixture and the substrate;
(d) forming an intermetallic compound layer on the substrate;
(e) forming an uneven structure including the metal powder on the intermetallic compound layer; And
(f) heat treating the substrate. The method according to claim 1,
Wherein the metal powder comprises an iron (Fe) -aluminum (Al) alloy powder or a chromium (Cr) -aluminum (Al) alloy powder. 3. The method of claim 2,
The iron (Fe) -aluminum (Al)
45 to 55% by weight of the aluminum (Al)
And the iron (Fe) constitutes the remainder. 3. The method of claim 2,
The chromium (Cr) -aluminum (Al)
45 to 55% by weight of the aluminum (Al)
And the chrome (Cr) constitutes the remainder. The method according to claim 1,
In the step (c), the substrate and the powder mixture are contacted by deepening the substrate with the powder mixture. The method according to claim 1,
The halide (Halide), the lithium chloride (LiCl), sodium chloride (NaCl), potassium chloride (KCl), such as the alkali metal chlorides, calcium chloride (CaCl _2), barium chloride (BaCl _2), ammonium chloride (NH ₄ Cl), fluorinated sodium (NaF), potassium fluoride (KF), lithium fluoride (LiF), magnesium fluoride (MgF _2), calcium fluoride (CaF _2), barium fluoride (BaF ₂₎ and ammonium fluoride (NH ₄ F), sodium iodide (NaI ), potassium iodide (KI), lithium iodide (LiI), magnesium iodide (MgI _2), calcium iodide (CaI _2), at least one from the group consisting of barium iodide (BaI ₂₎ and ammonium iodide (NH ₄ I) ≪ / RTI > The method according to claim 1,
The powder mixture may contain,
0.5 to 3% by weight of the halide powder,
And the metal powder constitutes the remainder. The method according to claim 1,
In the step (c), the heating is performed at 700 to 1000 占 폚 for 4 to 24 hours. The method according to claim 1,
In the step (d), the metal powder reacts with the halide powder to form a metal halide, and the metal-halide reacts with the substrate to form the intermetallic compound layer on the substrate ≪ / RTI > The method according to claim 1,
Wherein the intermetallic compound layer comprises aluminide. The method according to claim 1,
Wherein the step (e) includes the step of forming the concavo-convex structure by bonding the intermetallic compound layer with the metal powder. The method according to claim 1,
Wherein, in the step (f), the heating is performed at 700 캜 to 1000 캜 for 10 hours to 36 hours. The method according to claim 1,
In the step (f), the heating temperature and the heating time satisfy the following expression (1).
[Formula 1]
(d) ² > [exp (-234,000 / (R * 1273))] / [exp (-234,000 / (R * T))]
D is the size of the metal powder (10 ≤ d ≤ 106, in units of ㎛), R = 8.314 J / (mol * K), where h is the heating time in hours, T is the heating temperature in K, )) The method according to claim 1,
Wherein, in the step (f), the intermetallic compound layer is removed and a concave-convex structure is formed on the substrate. 15. The method of claim 14,
In the step (f), the intermetallic compound layer is solid solution by heat treatment and is diffused into the substrate. The method according to claim 1,
Wherein the step (f) is performed in an inert gas or a reducing gas atmosphere. 17. A metal catalyst module comprising a metal structure produced by the method of any one of claims 1-16.

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