KR20210056930A - Multi-layered aluminium composite material for absorbing neutron and methods of fabricating the same - Google Patents

Abstract

According to an embodiment of the present invention, a neutron-absorbing aluminum composite material of a multi-layer structure comprises: a first composite material layer having a first aluminum matrix and first neutron-absorbing particles dispersed in the first aluminum matrix; and a neutron-absorbing enhancing layer comprising second aluminum or a magnesium matrix and second neutron-absorbing particles dispersed in the second aluminum or the magnesium matrix, wherein the neutron-absorbing enhancing layer is interposed in the first composite material layer in a layered structure.

Description

Multi-layered aluminum composite material for absorbing neutron and methods of fabricating the same}

The present invention relates to an aluminum composite material and a method of manufacturing the same, and to a neutron-absorbing aluminum composite material having a multilayer structure and a method of manufacturing the same.

The development of safety materials that can guarantee the longevity and safety of social infrastructure to prevent and prevent damage caused by the globalization, complexity, and enlargement of disasters is emerging as a social issue. In particular, while experiencing the Fukushima nuclear power plant crisis caused by the major earthquake in the northeast of Japan, demand for the development of core materials for shielding/absorbing neutrons used for storing and transporting spent nuclear fuel in nuclear power plant operations is increasing.

Korean Patent Publication No. 20140092480 (2014-07-24)

An object of the present invention is to provide a multi-layered neutron-absorbing aluminum composite material capable of increasing neutron-absorbing capacity and a method of manufacturing the same. However, these problems are exemplary, and the scope of the present invention is not limited thereby.

According to an aspect of the present invention for solving the above problems, a multi-layered neutron-absorbing aluminum composite material is provided.

The multi-layered neutron-absorbing aluminum composite material includes: a first composite material layer having a first aluminum base and first neutron-absorbing particles dispersed in the first aluminum base; And a second aluminum or magnesium matrix and a second neutron absorbing particle dispersed in the second aluminum or magnesium matrix, but interposed in a layered structure in the first composite material layer, a neutron absorption reinforcing layer.

In the multilayered neutron absorbing aluminum composite material, the first neutron absorbing particles may be boron-based neutron absorbing particles, and the second neutron absorbing particles may be boron carbide particles.

In the multilayered neutron-absorbing aluminum composite material, the first neutron-absorbing particles may be boron-based neutron-absorbing particles, and the second neutron-absorbing particles may be gadolinium oxide particles.

In the multilayered neutron absorbing aluminum composite material, the first neutron absorbing particles may be boron-based neutron absorbing particles, and the second neutron absorbing particles may be BNNT particles.

In the multilayered neutron absorbing aluminum composite material, the first neutron absorbing particles are boron-based neutron absorbing particles, and the second neutron absorbing particles are BN, TiB ₂ , Sm ₂ O ₃ , Al ₃ Sm, Al ₂ Sm, and It may be at least one or more particles selected from AlSm.

The multi-layered neutron-absorbing aluminum composite material may further include an aluminum layer disposed in contact with the upper and lower surfaces of the first composite material layer. Further, it may further include a steel layer to which boron or gadolinium is added covering the aluminum layer.

The multi-layered neutron-absorbing aluminum composite material may further include a steel layer disposed in contact with the upper and lower surfaces of the first composite material layer.

According to another aspect of the present invention for solving the above problems, there is provided a method of manufacturing a multi-layered neutron-absorbing aluminum composite material.

The method of manufacturing the multi-layered neutron-absorbing aluminum composite material includes: preparing a first composite material structure including a first aluminum base and first neutron-absorbing particles dispersed in the first aluminum base; Forming a concave groove penetrating at least a portion of the central portion of the first composite material structure; Charging the mixed powder of the aluminum powder and the second neutron absorbing particle powder into the concave groove; And hot rolling the first composite material structure loaded with the mixed powder.

In the method of manufacturing the multilayered neutron-absorbing aluminum composite material, the hot rolling may be performed at a temperature equal to or lower than the melting point of aluminum.

According to the multi-layered neutron-absorbing aluminum composite material of the present invention made as described above and a method for manufacturing the same, it is possible to increase the neutron-absorbing capacity to a meaningful level. Of course, the scope of the present invention is not limited by these effects.

1 to 5 are views illustrating a multi-layered neutron-absorbing aluminum composite material according to various embodiments of the present disclosure.
6 is a diagram schematically illustrating a multi-layered neutron-absorbing aluminum composite material according to another embodiment of the present invention.
7 are photographs of a multi-layered neutron-absorbing aluminum composite material according to various embodiments shown in FIG. 6.
8 is a graph illustrating a weight reduction pattern per unit area over time in a specimen according to an experimental example of the present invention.
9 is a diagram schematically illustrating a multi-layered neutron-absorbing aluminum composite material according to another embodiment of the present invention.
10 is a schematic diagram of a composite material according to the first embodiment of the present invention, and FIG. 11 is a photograph of the composite material according to the first embodiment of the present invention.
12 is a schematic diagram of a composite material according to the first comparative example of the present invention, and FIG. 13 is a photograph of the composite material according to the first comparative example of the present invention.
14 is a graph comparing the thermal neutron absorption cross-sectional area coefficients of the composite material according to the first comparative example and the first example of the present invention.
15 is a view comparing neutron absorption capacity according to the size of neutron absorbing particles constituting the neutron absorbing aluminum composite material.
16 is a diagram sequentially illustrating a method of manufacturing a multi-layered neutron-absorbing aluminum composite material according to an embodiment of the present invention.
17 is a plan view photographs of a multilayered neutron-absorbing aluminum composite material implemented according to Experimental Examples 4 and 5 of the present invention.
18 is a cross-sectional view of a multi-layered neutron-absorbing aluminum composite material implemented according to Experimental Example 4 of the present invention.
FIG. 19 is a diagram showing the results of EPMA analysis in a neutron-absorbing enhanced layer and adjacent regions in a multilayered neutron-absorbing aluminum composite material implemented according to Experimental Example 4 of the present invention.
FIG. 20 is a cross-sectional view of photographs of a multi-layered neutron-absorbing aluminum composite material implemented according to Experimental Example 5 of the present invention, and a view showing EPMA analysis results in a neutron-absorbing enhanced layer and adjacent regions.
21 is a cross-sectional view of a multi-layered neutron-absorbing aluminum composite material implemented according to Experimental Example 4-1 of the present invention.
22 is a boundary area between the neutron absorbing reinforcing layer and the first composite material layer in the multilayered neutron absorbing aluminum composite material implemented according to Experimental Example 4-1 of the present invention (shown by dotted circles in FIG. 22(a)). Area) is a diagram showing the EPMA analysis result.
23 is a view showing the EPMA analysis results in all regions corresponding to the total thickness of the neutron absorption reinforcing layer in the multilayered neutron-absorbing aluminum composite material implemented according to Experimental Example 4-1 of the present invention.
24 is a cross-sectional view of a multi-layered neutron-absorbing aluminum composite material implemented according to Experimental Example 5-1 of the present invention.
FIG. 25 is a boundary area between the neutron absorption reinforcing layer and the first composite material layer in the multilayered neutron-absorbing aluminum composite material implemented according to Experimental Example 5-1 of the present invention (shown by dotted circles in FIG. 25(a)). Area) is a diagram showing the EPMA analysis result.
26 is a diagram illustrating an equipment for testing neutron shielding ability in an experimental example of the present invention.
27 is a graph comparing neutron absorption cross-sectional area coefficients of a multilayered neutron absorption aluminum composite material implemented according to an experimental example of the present invention.

Hereinafter, various embodiments of the present invention will be described in detail with reference to the accompanying drawings. The embodiments of the present invention are provided to more completely describe the present invention to those of ordinary skill in the art, and the following examples may be modified in various other forms, and the scope of the present invention is as follows. It is not limited to the examples. Rather, these embodiments are provided to make the present disclosure more faithful and complete, and to completely convey the spirit of the present invention to those skilled in the art.

1 to 5 are views illustrating a multi-layered neutron-absorbing aluminum composite material according to various embodiments of the present disclosure.

1 to 5, a multilayered neutron-absorbing aluminum composite material 100 according to various embodiments of the present invention includes a first aluminum base 112 and a first aluminum base 112 dispersed therein. A first composite material layer 110 having a neutron absorbing particle 114; And a second aluminum or magnesium base 122 and second neutron absorbing particles 124a, 124b, 124c, 124d, 124e dispersed in the second aluminum or magnesium base 122, but the first composite material layer ( 110) interposed in a layered structure, the neutron absorption reinforcing layer 120; includes.

The total thickness of the multilayered neutron-absorbing aluminum composite material 100 is, for example, 1.5 to 2 mm, of which the neutron-absorbing reinforcing layer 120 may have a thickness of, for example, 100 to 300 μm. . The neutron absorption enhancement layer 120 is a relatively high-density intermediate layer, and such a high-density region can improve neutron absorption capacity.

In the present application, the first aluminum base 112 and/or the second aluminum base 122 may be made of pure aluminum or an aluminum alloy, for example, an Al6061 alloy. Aluminum is a material with high ductility.

The first composite material layer 110 including the first aluminum base 112 and the first neutron absorbing particles 114 dispersed in the first aluminum base 112 may function as a neutron absorbing material. The first neutron absorbing particles 114 may be boron-based neutron absorbing particles, for example, boron carbide (B ₄ C). The volume fraction of the first neutron absorbing particles 114 in the first composite material layer 110 may be less than 60%.

Boron (B) constituting boron carbide (B ₄ C) is a material having a neutron absorption function. Boron carbide (B ₄ C) is a covalently bonded material, and is characterized by a high melting point (2450° C.) and high hardness (Knoop hardness: 2800 kg/mm2). Since natural boron contains about 20% ^{of the isotope 10} B having an atomic weight of 10, ^{and 10} β has a large absorption capacity of neutrons, the boron compound that combines the two can be used as a control material for a nuclear reactor or a shielding material for neutrons. Boron carbide contains a lot of boron, is chemically and thermally stable, and has excellent mechanical properties.

There are various manufacturing methods for implementing the first composite material layer 110. For example, when a mixed powder mixed with aluminum powder and boron carbide powder is rolled, highly ductile aluminum powder particles are plastically deformed by rolling and are integrated with each other to become an aluminum matrix, and the boron carbide powder is dispersed as particles in the aluminum matrix. Finally, the first composite material layer 110 including the first aluminum base 112 and the first neutron absorbing particles 114 dispersed in the first aluminum base 112 may be implemented.

In the multi-layered neutron-absorbing aluminum composite material 100, the second neutron-absorbing particles (124a, 124b, 124c, 124d, 124e) constituting the neutron-absorbing enhanced layer (120; 120a, 120b, 120c, 120d, 120e) May have a smaller particle size than the first neutron absorbing particles 114 constituting the first composite material layer 110. For example, while the particle size of the first neutron absorbing particles 114 is approximately 40 μm, the second neutron absorbing particles 124a, 124b, 124c, 124d, and 124e may have a particle size of approximately 1 μm. have.

However, in other modified embodiments of the present invention, the particle size of the second neutron absorbing particles 124a, 124b, 124c, 124d, 124e constituting the neutron absorbing enhanced layer 120 is the first composite material layer 110 It may be larger than the particle size of the first neutron absorbing particles 114 constituting ).

The present inventors have found that the neutron-absorbing aluminum composite material 100 having a multi-layered structure having a configuration in which the neutron-absorbing enhanced layer 120 is interposed in the first composite material layer 110 in a layered structure has a remarkably improved neutron-absorbing ability.

Hereinafter, various specific embodiments of the neutron-absorbing enhanced layer 120 constituting the multi-layered neutron-absorbing aluminum composite material 100 will be described.

Referring to FIG. 1, in a multilayered neutron-absorbing aluminum composite material 100, a second aluminum or magnesium matrix 122 and a second boron carbide particle dispersed in the second aluminum or magnesium matrix 122 The neutron absorption reinforcing layer 120a including the neutron absorption particles 124a is interposed in the first composite material layer 110 in a layered structure. For example, the neutron absorption reinforcing layer 120a may be interposed in a layered structure at the center of the first composite material layer 110.

The first neutron absorbing particles 114 may be boron-based neutron absorbing particles, for example, boron carbide (B ₄ C). The second neutron absorbing particles 124a may be, for example, boron carbide (B ₄ C) particles. _{The volume fraction of the boron carbide (B 4} C) particles, which are the second neutron absorbing particles 124a in the neutron absorption enhancing layer 120a, may be less than 60%.

Meanwhile, the particle size of the second neutron absorbing particles 124a, which is the second boron carbide particles, may be smaller than the particle size of the first neutron absorbing particles 114. For example, the first neutron absorbing particles 114 may have a particle size of approximately 40 μm, whereas the second boron carbide particles, the second neutron absorbing particles 124a, may have a particle size of approximately 1 μm. .

Referring to FIG. 2, in the multilayered neutron-absorbing aluminum composite material 100, the second aluminum or magnesium base 122 and the second neutron absorbing gadolinium oxide particles dispersed in the second aluminum or magnesium base 122 The neutron absorption enhancing layer 120b including the particles 124b is interposed in the first composite material layer 110 in a layered structure. For example, the neutron absorption reinforcing layer 120b may be interposed in a layered structure at the center of the first composite material layer 110.

The first neutron absorbing particles 114 may be boron-based neutron absorbing particles, for example, boron carbide (B ₄ C). The second neutron absorbing particles 124b may be, for example, gadolinium oxide particles.

The volume fraction of the gadolinium oxide particles, which is the second neutron absorbing particles 124b, in the neutron absorption enhancing layer 120a may be less than 50%.

Gadolinium has a neutron absorption cross-sectional area of 44,000 barn, which is excellent in absorbing neutrons. Meanwhile, the particle size of the second neutron absorbing particles 124b, which are gadolinium oxide particles, may be smaller than the particle size of the first neutron absorbing particles 114. For example, the first neutron absorbing particles 114 may have a particle size of about 40 μm, while the second neutron absorbing particles 124b, which are gadolinium oxide particles, may have a particle size of about 1 μm.

3, in the neutron-absorbing aluminum composite material 100 having a multilayer structure, the second neutron-absorbing particles, which are BNNT particles dispersed in the second aluminum or magnesium base 122 and the second aluminum or magnesium base 122 The neutron absorption enhancing layer 120c having (124c) is interposed in the first composite material layer 110 in a layered structure. For example, the neutron absorption reinforcing layer 120c may be interposed in a layered structure at the center of the first composite material layer 110.

Boron nitride nanotube (BNNT) is a material obtained by substituting carbon of graphene, which is a planar material, with boron and nitrogen, has similar thermal conduction and mechanical properties to carbon nanotubes, and has thermal and chemical stability at high temperatures of 800°C or higher. It is a material with excellent thermal neutron absorption.

The first neutron absorbing particles 114 may be boron-based neutron absorbing particles, for example, boron carbide (B ₄ C). The second neutron absorbing particles 124c may be, for example, BNNT particles.

The volume fraction of BNNT particles, which is the second neutron absorbing particles 124c, in the neutron absorption enhancing layer 120a may be less than 30%.

Meanwhile, the particle size of the second neutron absorbing particles 124c, which are BNNT particles, may be smaller than the particle size of the first neutron absorbing particles 114. For example, the first neutron absorbing particles 114 may have a particle size of about 40 μm, whereas the second neutron absorbing particles 124c, which are BNNT particles, may have a particle size of about 1 μm.

Referring to FIG. 4, in the neutron-absorbing aluminum composite material 100 of a multilayer structure, BN, TiB ₂ , Sm ₂ O dispersed in the second aluminum or magnesium base 122 and the second aluminum or magnesium base 122 ₃ , Al ₃ Sm, Al ₂ Sm, and at least one particle selected from AlSm, a neutron absorption reinforcing layer (120d) having a second neutron absorbing particles (124d) in a layered structure in the first composite material layer (110). Intervened. For example, the neutron absorption reinforcing layer 120d may be interposed in a layered structure at the center of the first composite material layer 110.

The first neutron absorbing particles 114 may be boron-based neutron absorbing particles, for example, boron carbide (B ₄ C). The second neutron absorbing particles 124d may be, for example, at least one or more particles selected from _{BN, TiB 2} , Sm ₂ O ₃ , Al ₃ Sm, Al _{2 Sm, and AlSm.} Samarium (Sm) has a neutron absorption cross-sectional area of 6,500 barn, and has excellent neutron absorption capacity.

Meanwhile, the average particle size of the second neutron absorbing particles 124d, which is at least any one or more particles selected from BN, TiB ₂ , Sm ₂ O ₃ , Al ₃ Sm, Al _{2 Sm, and AlSm, is the first neutron absorbing particle 114} May be smaller than the particle size of For example, while the particle size of the first neutron absorbing particles 114 is approximately 40 μm, at least one or more particles selected from _{BN, TiB 2} , Sm ₂ O ₃ , Al ₃ Sm, Al _{2 Sm and AlSm} The second neutron absorbing particles 124d may have a particle size of about 1 μm.

5, in the multilayered neutron-absorbing aluminum composite material 100, boron carbide particles, gadolinium oxide particles dispersed in the second aluminum or magnesium base 122 and the second aluminum or magnesium base 122, BNNT particles, BN particles, TiB ₂ particles, Sm ₂ O ₃ particles, Al ₃ Sm particles, Al ₂ Sm particles, and a plurality of mixed particles arbitrarily selected from the group consisting of AlSm particles, second neutron absorbing particles (124e) The neutron absorption reinforcing layer 120e is interposed in the first composite material layer 110 in a layered structure. For example, the neutron absorption reinforcing layer 120e may be interposed in a layered structure at the center of the first composite material layer 110.

Meanwhile, a plurality of mixed particles arbitrarily selected from the group consisting of boron carbide particles, gadolinium oxide particles, BNNT particles, BN particles, TiB ₂ particles, Sm ₂ O ₃ particles, Al ₃ Sm particles, Al _{2 Sm particles and AlSm particles} The average particle size of the second neutron absorbing particles 124e may be smaller than the particle size of the first neutron absorbing particles 114. For example, the first neutron absorbing particles 114 may have a particle size of about 40 μm, while the second neutron absorbing particles 124e may have a particle size of about 1 μm.

6 is a diagram schematically illustrating a multi-layered neutron-absorbing aluminum composite material 100 according to another embodiment of the present invention.

1 to 6, a multilayered neutron-absorbing aluminum composite material 100 according to another embodiment of the present invention includes a first aluminum base 112 and a first aluminum base 112 dispersed in the first aluminum base 112. The first composite material layer 110 having neutron absorbing particles 114; And a second aluminum or magnesium base 122 and second neutron absorbing particles 124; 124a, 124b, 124c, 124d, 124e) dispersed in the second aluminum or magnesium base 122, but the first composite material Including, the neutron absorption reinforcing layer 120 interposed in the layered structure in the layer 110, but may further include an aluminum layer 130 disposed in contact with the upper and lower surfaces of the first composite material layer 110. have. The first composite material layer 110 shown in FIG. 6; And the neutron absorption enhancement layer 120 corresponds to the structure described with reference to any one of FIGS. 1 to 5. The surface metal layer such as the aluminum layer 130 prevents particles of the neutron absorbing reinforcing layer 120 from falling out of the multilayered neutron absorbing aluminum composite material 100, and improves surface roughness, corrosion resistance, oxidation resistance, and welding characteristics. Let it.

7 are photographs of a multi-layered neutron-absorbing aluminum composite material according to various embodiments shown in FIG. 6.

Figure 7 (a) is a first composite material layer 110 shown in Figure 6; And the case where the neutron absorption reinforcing layer 120 has the structure shown in FIG. 1, and FIG. 7(b) is a first composite material layer 110 shown in FIG. 6; And the case where the neutron absorption reinforcing layer 120 has the structure shown in FIG. 2, and FIG. 7(c) is a first composite material layer 110 shown in FIG. 6; And the case where the neutron absorption enhancing layer 120 has the structure shown in FIG. 3. In Fig. 7C, the volume fraction of the BNNT particles as the second neutron absorbing particles is 2% in the neutron absorption enhancing layer.

8 is a graph illustrating a weight reduction pattern per unit area over time in a specimen according to an experimental example of the present invention. The specimen'MMC' corresponds to the neutron-absorbing aluminum composite material of the multilayer structure shown in FIG. 1, and the specimen'Al+MMC' corresponds to the neutron-absorbing aluminum composite material of the multilayer structure shown in FIG. 'Al' is a reference specimen and corresponds to a simple aluminum specimen.

Referring to Figure 8, in the case of the specimen'MMC', the _{weight per unit area is significantly reduced due to oxidation and dropping of boron carbide (B 4} C), but in the case of the specimen'Al+MMC', the weight per unit area is reduced due to the presence of an aluminum layer on the surface. It can be seen that there is no change in weight. That is, it can be seen that the structure shown in FIG. 6 has better oxidation resistance properties than the structure shown in FIG. 1.

Meanwhile, the neutron-absorbing aluminum composite material 100 having a multilayer structure according to another modified embodiment of the present invention disclosed in FIG. 6 is an aluminum layer 130 disposed in contact with the upper and lower surfaces of the first composite material layer 110. Instead, it may include a steel layer 130.

9 is a diagram schematically illustrating a multi-layered neutron-absorbing aluminum composite material 100 according to another embodiment of the present invention.

Referring to FIG. 9, a multilayered neutron-absorbing aluminum composite material 100 according to another embodiment of the present invention absorbs the first neutrons dispersed in the first aluminum base 112 and the first aluminum base 112. The first composite material layer 110 having the particles 114; The second aluminum or magnesium base 122 and the second neutron absorbing particles 124; 124a, 124b, 124c, 124d, 124e) dispersed in the second aluminum or magnesium base 122 are provided, but the first composite material layer A neutron absorption enhancing layer 120 interposed in a layered structure in (110); And an aluminum layer 130 disposed in contact with the upper and lower surfaces of the first composite material layer 110, and may further include a steel layer 140 covering the aluminum layer 130.

A first composite material layer 110 shown in FIG. 9; And the neutron absorption enhancement layer 120 corresponds to the structure described with reference to any one of FIGS. 1 to 5. Boron or gadolinium may be added to the steel layer 140. The surface metal layer such as the steel layer 140 prevents particles of the neutron absorbing reinforcing layer 120 from falling out of the multilayered neutron absorbing aluminum composite material 100, and improves surface roughness, corrosion resistance, oxidation resistance, and welding characteristics. Let it.

So far, a multi-layered neutron-absorbing aluminum composite material according to various embodiments of the present invention has been described. One of the features of these embodiments is that the neutron absorption reinforcing layer 120 includes second neutron absorbing particles 124 (124a, 124b, 124c, 124d, 124e) dispersed in the second aluminum or magnesium matrix 122, The neutron absorption reinforcing layer 120 including the second neutron absorbing particles is interposed and positioned in the first composite material layer 110 in a layered structure. That is, one of the main features is that the second neutron-absorbing particles are not randomly distributed in a multi-layered neutron-absorbing aluminum composite material, but have a layered structure in the form of a layer.

10 is a schematic diagram of a composite material according to the first embodiment of the present invention, and FIG. 11 is a photograph of the composite material according to the first embodiment of the present invention. 12 is a schematic diagram of a composite material according to the first comparative example of the present invention, and FIG. 13 is a photograph of the composite material according to the first comparative example of the present invention. 14 is a graph comparing the thermal neutron absorption cross-sectional area coefficients of the composite material according to the first comparative example and the first example of the present invention.

10 and 11 are the multilayered neutron-absorbing aluminum composite material shown in FIG. 6, wherein the first neutron-absorbing particles 114 are boron carbide (B ₄ C), which is a boron-based neutron-absorbing particles, and a second neutron-absorbing particle. The particles 124b are gadolinium oxide particles, the first aluminum base 112 is a base constituting the first composite material layer, and the second aluminum base 122 is a base constituting the neutron absorption reinforcing layer. The aluminum layer 130 is a surface metal layer that prevents particles of the neutron absorption reinforcing layer from falling off, and improves surface roughness, corrosion resistance, oxidation resistance, and welding characteristics.

Referring to FIG. 10, the second neutron absorbing particles 124b are not randomly distributed in a multilayered neutron absorbing aluminum composite material, but have a layered structure in the form of a layer. _It is denoted as 2 O _3.

12, the first neutron absorbing particles 114 are boron carbide (B ₄ C), which is a boron-based neutron absorbing particles, and the second neutron absorbing particles 124b are gadolinium oxide particles, and the first aluminum matrix ( 112) is the base. 12 and 13, the second neutron absorbing particles 124b do not have a layered structure in the form of a layer in the multilayered neutron absorbing aluminum composite material, but are randomly distributed and disposed.

14, the thermal neutron absorption cross-sectional area ^{of the composite material according to the first embodiment of the present invention is 14.5 (cm −1} ), whereas the thermal neutron absorption cross-sectional area of the composite material according to the first embodiment of the present invention is 14.5 (cm −1 ). It can be seen that the coefficient is 15.4 (cm ^{-1 ).}

In the composite material according to the first comparative example of the present invention and the composite material according to the first embodiment of the present invention, 20 vol% B ₄ C/Al6061 powder and 10 vol% Gd ₂ O ₃ /Al6061 powder were used in the same manner. Although the material composition is the same in that, the neutron absorption capacity can be improved in a structure in which the second neutron absorbing particles are arranged in a layered structure (Example 1) in a layered structure rather than in a structure in which the second neutron absorbing particles are randomly distributed and arranged (Comparative Example 1). can confirm.

15 is a view comparing neutron absorption capacity according to the size of neutron absorbing particles constituting the neutron absorbing aluminum composite material.

_{Referring to FIG. 15, when the average particle size of boron carbide (B 4} C), which is neutron absorbing particles embedded and dispersed in an aluminum matrix, is 1 μm, the thermal neutron absorption cross-sectional area coefficient is 24.4 (cm ^-1 ), whereas boron carbide When the _{average particle size of (B 4} C) is 40 μm, it can be seen that the thermal neutron absorption cross-sectional area coefficient is 20.8 (cm ^{-1 ).}

That is, it can be seen that the neutron absorption capacity may vary depending on the size of the neutron absorbing particles constituting the multilayered neutron absorbing aluminum composite material.

16 is a diagram sequentially illustrating a method of manufacturing a multi-layered neutron-absorbing aluminum composite material 100 according to an embodiment of the present invention.

1 to 5 and 16, a method of manufacturing a multi-layered neutron-absorbing aluminum composite material 100 according to an embodiment of the present invention includes (a) the first aluminum base 112 and the first aluminum Preparing a first composite material structure 110 having the first neutron absorbing particles 114 dispersed in the base 112; (b) forming a concave groove 116 penetrating at least a portion of the central portion of the first composite material structure 110; (c) charging the mixed powder 126 of the aluminum powder and the second neutron absorbing particle powder into the concave groove 116; (d) hot rolling the first composite material structure 110 loaded with the mixed powder 126 using a rolling roll 200; includes.

By performing the steps (a) to (d), the multi-layered neutron-absorbing aluminum composite material 100 disclosed in FIGS. 1 to 5 may be implemented.

Particularly, in order to prevent the mixed powder 126 from dropping out during the hot rolling process after charging the mixed powder 126 of the aluminum powder and the second neutron absorbing particle powder in the concave groove 116, the concave groove An additional sealing operation to cover (116) can be performed.

The step of hot rolling may be performed at a temperature below the melting point of aluminum (eg, 500 to 600°C).

When the mixed powder 126 of the aluminum or magnesium powder and the second neutron absorbing particle powder is rolled, the highly ductile aluminum or magnesium powder particles in the mixed powder 126 are plastically deformed by rolling and are integrated with each other to form a second aluminum or magnesium matrix. (122), and the second neutron absorbing particle powder among the mixed powder 126 is dispersed as particles in the second aluminum or magnesium matrix 122 to become the second neutron absorbing particles 124, and finally, the second aluminum or magnesium A neutron absorption reinforcing layer having a base 122 and second neutron absorbing particles 124 dispersed in the second aluminum or magnesium base 122, but interposed in a layered structure in the first composite material layer 110 ( 120) can be implemented.

Experimental example

Hereinafter, a preferred experimental example is presented to aid the understanding of the present invention. However, the following experimental examples are only intended to aid understanding of the present invention, and the present invention is not limited by the following experimental examples.

Experimental example 1st composite material layer Neutron absorption enhanced layer Experimental Example 1 (Specimen 1) Al-5%B ₄ C - Experimental Example 2 (Specimen 2) Al-10%B ₄ C - Experimental Example 3 (Specimen 3) Al-20%B ₄ C - Experimental Example 4 (Specimen 4) Al-20%B ₄ C Al-20%B ₄ C Experimental Example 5 (Specimen 5) Al-20%B ₄ C Al-20%GdO ₂ Experimental Example 6 (Specimen 6) Al-20%B ₄ C Al-30%GdO ₂ Experimental Example 7 (Specimen 7) Al-20%B ₄ C Al-BNNT

Table 1 shows the material layers constituting the specimen of the experimental example of the present invention, and all the rolling temperatures for implementing this were applied at 550°C.

Referring to Table 1, specimen 1 is composed of only a first composite material layer having a first aluminum base and first neutron absorbing particles dispersed while having a volume ratio of 5% in the first aluminum base, and specimen 2 is It consists only of a first composite material layer having the first aluminum base and the first neutron absorbing particles dispersed while having a volume ratio of 10% in the first aluminum base, and the specimen 3 is the first aluminum base and the first aluminum. It consists only of the first composite material layer having the first neutron absorbing particles dispersed while having a volume ratio of 20% in the matrix. Specimens 1 to 3, as comparative examples of the present invention, do not introduce a configuration of a neutron absorption reinforcing layer interposed in a layered structure in the first composite material layer.

Specimen 4 includes a first composite material layer including a first aluminum matrix and first neutron absorbing particles dispersed while having a volume ratio of 20% in the first aluminum matrix; And second neutron absorbing particles, which are second boron carbide particles dispersed while having a volume ratio of 20% in the second aluminum base and the second aluminum base, but interposed in a layered structure in the first composite material layer, absorbing neutrons. Reinforcement layer; consists of.

Specimen 5 includes a first composite material layer including a first aluminum matrix and first neutron absorbing particles dispersed while having a volume ratio of 20% in the first aluminum matrix; And second neutron absorbing particles, which are gadolinium oxide particles dispersed while having a volume ratio of 20% in the second aluminum base and the second aluminum base, but interposed in a layered structure in the first composite material layer. Consists of;

Specimen 6 includes a first composite material layer including a first aluminum matrix and first neutron absorbing particles dispersed while having a volume ratio of 20% in the first aluminum matrix; And second neutron-absorbing particles, which are gadolinium oxide particles dispersed while having a volume ratio of 30% in the second aluminum base and the second aluminum base, but interposed in a layered structure in the first composite material layer. Consists of;

Specimen 7 includes a first composite material layer including a first aluminum matrix and first neutron absorbing particles dispersed while having a volume ratio of 20% in the first aluminum matrix; And a second aluminum base and second neutron absorbing particles, which are BNNT particles dispersed in the second aluminum base, but interposed in a layered structure in the first composite material layer, a neutron absorption reinforcing layer. Specimens 4 to 7 are examples of the present invention, wherein the second neutron absorbing particles have a smaller particle size than the first neutron absorbing particles.

17 is a plan view of a multi-layered neutron-absorbing aluminum composite material implemented according to the experimental example of the present invention.

Figure 17 (a) is a multi-layered neutron-absorbing aluminum composite material according to an embodiment of the present invention, corresponding to Specimen 4, and Figure 17 (b) is a multi-layered neutron-absorbing aluminum composite according to an embodiment of the present invention. It corresponds to specimen 5 as a material.

18 is a cross-sectional view of a multi-layered neutron-absorbing aluminum composite material implemented according to the experimental example (Specimen 4) of the present invention.

Referring to FIG. 18, a first composite material layer 110 including a first aluminum base and first neutron absorbing particles 114 dispersed while having a volume ratio of 20% in the first aluminum base 112; And second neutron absorbing particles, which are second boron carbide particles dispersed while having a volume ratio of 20% in the second aluminum base and the second aluminum base, and interposed in the first composite material layer 110 in a layered structure. , The neutron absorption reinforcing layer 120; It is possible to check the cross-section of the neutron-absorbing aluminum composite material of a multi-layered structure. Relatively bright areas represent aluminum, and relatively dark areas represent boron carbide particles. The thickness of the neutron absorption enhancing layer is 230 to 290 μm, the size of the second boron carbide particles is about 1 μm, and the size of the first neutron absorbing particles 114 is observed to be about 40 μm. In particular, the second neutron absorbing particles, which are the second boron carbide particles, are uniformly dispersed in the neutron absorption strengthening layer 120, and the interface between the neutron absorption strengthening layer 120 and the first composite material layer 110 is sound. can confirm.

19 is a view showing the results of EPMA analysis in the neutron absorption reinforcing layer and adjacent regions in a multi-layered neutron-absorbing aluminum composite material implemented according to Experimental Example (Specimen 4) of the present invention.

Referring to FIG. 19, the thickness of the neutron absorption strengthening layer is 230 to 290 μm, the second neutron absorbing particles, which are the second boron carbide particles, are uniformly dispersed in the neutron absorption strengthening layer, and the neutron absorption strengthening layer and the first composite It can be confirmed that the interface between the material layers is sound.

20 is a cross-sectional view of photographs of a multi-layered neutron-absorbing aluminum composite material implemented according to Experimental Example (Specimen 5) of the present invention, and a view showing EPMA analysis results in the neutron-absorbing enhanced layer and adjacent regions.

Referring to FIG. 20, a first composite material layer including a first aluminum (Al6061) base and first neutron absorbing particles dispersed while having a volume ratio of 20% in the first aluminum base; And second neutron absorbing particles, which are gadolinium oxide particles dispersed while having a volume ratio of 20% in the second aluminum (Al6061) base and the second aluminum base, but interposed in a layered structure in the first composite material layer, neutrons In the multi-layered neutron-absorbing aluminum composite material consisting of an absorption strengthening layer; the second neutron absorbing particles, which are gadolinium oxide particles, are uniformly dispersed in the neutron absorption strengthening layer, and between the neutron absorption strengthening layer and the first composite material layer. It can be confirmed that the interface is sound.

Meanwhile, experimental examples in which the neutron-absorbing aluminum composite material of the multilayer structure described above is actually implemented in FIG.

21 is a cross-sectional view of a multi-layered neutron-absorbing aluminum composite material implemented according to Experimental Example 4-1 of the present invention.

Referring to FIG. 21, the multilayered neutron-absorbing aluminum composite material implemented according to Experimental Example 4-1 of the present invention includes a first aluminum base and a first neutron-absorbing particle dispersed in the first aluminum base. A composite material layer 110; And second neutron absorbing particles, which are second boron carbide particles dispersed while having a volume ratio of 20% in the second aluminum base and the second aluminum base, and interposed in the first composite material layer 110 in a layered structure. It includes, and further includes an aluminum layer 130 disposed in contact with the upper and lower surfaces of the first composite material layer 110. The aluminum layer 130 may be understood as an aluminum surface layer.

22 is a boundary area between the neutron absorbing reinforcing layer and the first composite material layer in the multilayered neutron absorbing aluminum composite material implemented according to Experimental Example 4-1 of the present invention (shown by dotted circles in FIG. 22(a)). Area) is a diagram showing the EPMA analysis result.

Referring to FIG. 22, a uniform distribution of the first aluminum matrix constituting the first composite material layer and the first neutron absorbing particles dispersed in the first aluminum matrix can be confirmed. In addition, a uniform distribution of the second aluminum matrix constituting the neutron absorption reinforcing layer and the second boron carbide particles dispersed in the second aluminum matrix can be confirmed. It can be seen that the size of the first neutron absorbing particles is about 40 μm, while the size of the second boron carbide particles is about 1 μm.

23 is a view showing the EPMA analysis results in all regions corresponding to the total thickness of the neutron absorption reinforcing layer in the multilayered neutron-absorbing aluminum composite material implemented according to Experimental Example 4-1 of the present invention.

Referring to FIG. 23, in the entire area corresponding to the total thickness of the neutron absorption reinforcing layer (the area indicated by the dotted circle in FIG. 23(a)), the second aluminum base and the second carbonization dispersed in the second aluminum base. It can be seen that the distribution of boron particles is uniform.

24 is a cross-sectional view of a multi-layered neutron-absorbing aluminum composite material implemented according to Experimental Example 5-1 of the present invention.

Referring to FIG. 24, the multi-layered neutron-absorbing aluminum composite material implemented according to Experimental Example 5-1 of the present invention includes a first aluminum base and a first neutron-absorbing particle dispersed in the first aluminum base. A composite material layer 110; And second neutron absorbing particles, which are gadolinium oxide particles dispersed while having a volume ratio of 20% in the second aluminum base and the second aluminum base, but interposed in a layered structure in the first composite material layer 110, neutrons The absorption reinforcing layer 120b; includes, and further includes an aluminum layer 130 disposed in contact with the upper and lower surfaces of the first composite material layer 110. The aluminum layer 130 may be understood as an aluminum surface layer. Meanwhile, a gadolinium oxide layer 135 may be further selectively formed between the aluminum layer 130 and the first composite material layer 110.

25 is a boundary area between the neutron absorption reinforcing layer and the first composite material layer in the multilayered neutron-absorbing aluminum composite material implemented according to Experimental Example 5-1 of the present invention (shown by dotted circles in FIG. 25(a)). Area) is a diagram showing the EPMA analysis result.

Referring to FIG. 25, a uniform distribution of the first aluminum matrix constituting the first composite material layer and the first neutron absorbing particles dispersed in the first aluminum matrix can be confirmed. In addition, a uniform distribution of the second aluminum matrix constituting the neutron absorption reinforcing layer and the gadolinium oxide particles dispersed in the second aluminum matrix can be confirmed. It can be seen that the size of the first neutron absorbing particles is about 40 μm, whereas the size of the gadolinium oxide particles is about 10 μm.

Hereinafter, the result of testing the neutron absorption capacity of the specimen according to the experimental example of the present invention will be described.

26 is a diagram illustrating an equipment for testing neutron shielding ability in an experimental example of the present invention, and FIG. 27 is a comparison of the neutron absorption cross-sectional area coefficients of a multi-layered neutron-absorbing aluminum composite material implemented according to the experimental example of the present invention. It is a graph.

Referring to FIG. 26, the emission rate of the Am-Be neutron source was 1.227x10 ⁷ s ^-1 , and a specimen was mounted between the detector and the neutron source.

Referring to Figure 27, the neutron absorption cross-section coefficient of the comparative example sample 1 of the present invention is 4.5cm ^-1, the neutron absorption cross-section coefficient of the specimen 2 is 8.25cm ^-1, the neutron absorption cross-section coefficient of the specimen 3 is 13.91cm ^{- 1} , whereas the neutron absorption cross-sectional area coefficient of Specimen 4, which is ^{an example of the present invention, is 18.1cm -1} , and the neutron absorption cross-sectional area modulus of Specimen 5, which is an example of the present invention, is 19.7cm ^-1 , and the neutron absorption cross-sectional area coefficient of Specimen 6 It can be seen that is 28.8cm ^-1.

That is, the present invention introduces the configuration of the neutron absorption strengthening layer interposed in the first composite material layer in a layered structure compared to the comparative example of the present invention in which the configuration of the neutron absorption strengthening layer interposed in the first composite material layer It can be seen that the neutron absorption capacity is excellent in the embodiments of the invention.

The present invention has been described with reference to the embodiments shown in the drawings, but these are merely exemplary, and those of ordinary skill in the art will appreciate that various modifications and equivalent other embodiments are possible therefrom. Therefore, the true technical protection scope of the present invention should be determined by the technical spirit of the appended claims.

Claims (10)

A first composite material layer comprising a first aluminum matrix and first neutron absorbing particles dispersed in the first aluminum matrix;
Comprising a second aluminum or magnesium matrix and a second neutron absorbing particles dispersed in the second aluminum or magnesium matrix, but interposed in a layered structure in the first composite material layer, a neutron absorption reinforcing layer; including,
Multi-layered neutron-absorbing aluminum composite material. The method of claim 1,
The first neutron absorbing particles are boron-based neutron absorbing particles,
The second neutron absorbing particles are boron carbide particles,
Multi-layered neutron-absorbing aluminum composite material. The method of claim 1,
The first neutron absorbing particles are boron-based neutron absorbing particles,
The second neutron absorbing particles are gadolinium oxide particles, characterized in that,
Multi-layered neutron-absorbing aluminum composite material. The method of claim 1,
The first neutron absorbing particles are boron-based neutron absorbing particles,
The second neutron absorbing particles are characterized in that the BNNT particles,
Multi-layered neutron-absorbing aluminum composite material. The method of claim 1,
The first neutron absorbing particles are boron-based neutron absorbing particles,
The second neutron absorbing particles are at least one or more particles selected _{from BN, TiB 2} , Sm ₂ O ₃ , Al ₃ Sm, Al _{2 Sm and AlSm,}
Multi-layered neutron-absorbing aluminum composite material. The method of claim 1,
Further comprising an aluminum layer disposed in contact with the upper and lower surfaces of the first composite material layer,
Multi-layered neutron-absorbing aluminum composite material. The method of claim 6,
Further comprising a steel layer to which boron or gadolinium is added covering the aluminum layer,
Multi-layered neutron-absorbing aluminum composite material. The method of claim 1,
Further comprising a steel layer disposed in contact with the upper and lower surfaces of the first composite material layer,
Multi-layered neutron-absorbing aluminum composite material. Preparing a first composite material structure including a first aluminum matrix and first neutron absorbing particles dispersed in the first aluminum matrix;
Forming a concave groove penetrating at least a portion of the central portion of the first composite material structure;
Charging the mixed powder of the aluminum powder and the second neutron absorbing particle powder into the concave groove;
Including; the step of hot rolling the first composite material structure charged with the mixed powder;
Manufacturing method of multi-layered neutron-absorbing aluminum composite material. The method of claim 9,
The hot rolling step is characterized in that it is carried out at a temperature below the melting point of aluminum,
Manufacturing method of multi-layered neutron-absorbing aluminum composite material.

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