KR101650342B1 - Functionally graded dual-nanoparticlate-reinforced aluminum matrix bulk materials and preparation method thereof - Google Patents

Abstract

The present invention relates to a process for producing a silicon nitride film, which comprises an aluminum layer, at least one layer containing aluminum and carbon nanotubes and containing or not containing nano SiC, and containing the aluminum and carbon nanotubes, Characterized in that the layer is laminated on one or both surfaces of the aluminum layer and aluminum and the carbon nanotubes are uniformly dispersed in each layer, and a manufacturing method thereof will be.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dual nanoparticle-reinforced aluminum tilted functional material and a method of manufacturing the same. BACKGROUND ART < RTI ID = 0.0 >

The present invention relates to a dual nanoparticle reinforced aluminum tilted functional material and a method of manufacturing the same.

Functionally Graded Materials refers to materials that continuously change the composition or tissue distribution of a material from the surface of the material toward the center depending on the use and required characteristics of the material. The graded functional materials proposed in Japan in the early 1980s are characterized in that internal or microstructures are distributed with a gradient in concentration from the surface to the backside. The first graded functional material was a metal-ceramic super-heat-resistant composite of the space shuttle.

With the development of high-tech industries in recent years, there is an increasing demand for materials to be used in an atmosphere that tilts in various industrial fields such as temperature gradient, stress gradient, pressure gradient, etc., and development of tilting functional materials having durability in such environments is required. Representative industrial fields that are expected to have various applications are aerospace, reactor outer wall, lightweight bulletproof, etc., and slope functionalization of materials is required.

Since it is very difficult to change the composition or the structure continuously, a method of combining materials having different characteristics into a plurality of layers is often used as a method of producing a gradient functional material. Examples of such methods include powder sintering, slurry deposition, spraying, and evaporation. Many developments have been made centering on composite materials using metals and ceramics.

Carbon nanotubes (CNTs) have been attracting much attention due to their excellent physical / chemical properties since their discovery in 1991, but the production of industrial parts using CNT-reinforced materials has been hampered by difficulties in manufacturing, interface properties between CNTs and base metal, And so on.

The inventor of the present invention recently proposed a method of using nSiC as a dispersing agent in a ball milling process in order to effectively disperse CNTs in an Al powder. According to this method, almost spherical nSiC easily disperses linearly formed CNTs in an Al matrix (Korean Patent No. 1418983).

Korean Patent Application No. 2007-0138890 (the name of the invention: a method for producing a preformed body of a metal base composite material having a graded functional layer structure) Korean Patent Application No. 2012-7017036 (Title of the Invention: Metal Matrix Composite Material Containing Carbon Nanotube-Injected Fiber Material and Method for Producing the Same)

It is an object of the present invention to provide a method of manufacturing a carbon nanotube and a method of manufacturing the same, which comprises an aluminum layer and a layer containing aluminum, carbon nanotubes and nano SiC, wherein aluminum is reinforced by carbon nanotubes and nano SiC, Aluminum is uniformly dispersed and the layers are laminated in a plurality of layers so that the content of carbon nanotubes has a concentration gradient so that a double nanoparticle-reinforced aluminum gradient functional material which can be used for producing industrial parts using carbon nanotube- And a method for producing the same.

It is an object of the present invention to provide a method of manufacturing a semiconductor device comprising an aluminum layer, at least one layer containing aluminum and carbon nanotubes and containing or not containing nano SiC,

The layer containing the aluminum and the carbon nanotubes and containing or not containing the nano SiC is laminated on one surface or both surfaces of the aluminum layer and the aluminum and the carbon nanotubes are uniformly dispersed in each layer Features,

Dual nanoparticle reinforced aluminum gradient functional material.

It is also an object of the present invention to provide a method of manufacturing a carbon nanotube film by stacking two or more layers containing aluminum, carbon nanotubes and nano SiC, wherein the two or more layers are stacked in the order of increasing or decreasing carbon nanotube content Lt; RTI ID = 0.0 > aluminosilicon < / RTI > functional material.

It is also an object of the present invention to provide a method for producing a composite material comprising the steps of: laminating and sintering aluminum powder, composite powder of aluminum and carbon nanotubes, composite powder in which aluminum, carbon nanotube and nano SiC particles are uniformly dispersed, This is achieved by a method for producing a nanoparticle reinforced aluminum gradient functional material.

According to the present invention, there is provided an aluminum gradient functional material reinforced with double nanoparticles of carbon nanotubes and nano SiC and a method of manufacturing the same.

In the present invention, it is possible to manufacture a material having a tilted function in a dense structure through ball milling and discharge plasma sintering process. It was confirmed that carbon nanotubes were more dispersed in Al particles by adding nano SiC as a dispersant, and each inclined functional layer had a rigid bonding structure in which no serious defects or pores were found. Nano-sized aluminum carbide was found in the carbon nanotube layer, but was not detected by X-ray diffraction analysis due to the small amount of distribution in the limited area. The partially formed aluminum carbide was embedded over the aluminum matrix and grain boundaries. Aluminum carbide of such a nano-tie rod structure induces the stress transferring effect of the material, thereby enhancing the strengthening ability.

The Vickers hardness of the graded functional layer varies depending on the composition of the inclined layer, and the layer having a high content of nano SiC exhibits a maximum hardness four times higher than that of pure aluminum.

Through Raman analysis, it was confirmed that CNTs acted both as strengthening and lubricant in the ball milling process. These inclined functional materials are expected to be applicable not only to double nano-particle reinforced aluminum composites but also to composite materials based on polymers, ceramics, and metal matrix materials.

1 is an FE-SEM photograph of raw aluminum (a), nano SiC (b), average diameter 20 nm CNT (c) and average diameter 100 nm CNT (d) particles used in the present invention.
FIG. 2 is a FE-SEM photograph of composite powder according to the content of CNT and nano SiC. 10% vol.% CNT-30 vol.% nSiC, gi: Al-30 vol.% CNT-10 vol.% nSiC)
Fig. 3 is a photograph of a gradient functional material made by laminating double nanoparticle reinforced aluminum composite powder. (a: Al-10% CNT composite layered on pure Al layer, b: pure Al layer, Al-10% CNT-30% SiC composite layer and Al-30% CNT-10% 10% CNT-30% SiC composite material layer, and Al-30% CNT-10% SiC composite material layer were stacked in this order)
Fig. 4 is an FE-SEM photograph of the cross section of each layer and interlayer interface of aluminum and double nanoparticle reinforced aluminum composite powder.
5 is a TEM photograph of the interface between aluminum and an aluminum-CNT composite material.
6 shows the results of sintering according to the contents of CNT and nano SiC (Al-10 vol.% CNT-30 vol.% NSiC and Al-30 vol.% CNT-10 vol.% NSiC) of double- TEM image of the composite material interface.
Figure 7 is a Raman spectrum of pure CNTs and graded functional materials according to embodiments of the present invention.
FIG. 8 is a result of an X-ray diffraction analysis of a functional material having an inclination according to an embodiment of the present invention.

The present invention relates to a laminate comprising an aluminum layer, at least one layer containing aluminum and carbon nanotubes and containing or not containing nano SiC,

The layer containing the aluminum and the carbon nanotubes and containing or not containing the nano SiC is laminated on one surface or both surfaces of the aluminum layer and the aluminum and the carbon nanotubes are uniformly dispersed in each layer Features,

Dual nanoparticle reinforced aluminum graded functional materials.

In the present invention, "double nanoparticle" means two types of nanoparticles, carbon nanotube and nano SiC.

In the present invention, "inclined function" means that when one or more layers containing an aluminum layer, aluminum and carbon nanotubes and containing or not containing nano SiC are laminated, the carbon nanotube content But it is laminated so as to have a concentration gradient in which the content of carbon nanotubes increases or decreases between the respective layers, which means that the material has an inclined function as a whole.

In the present invention, the aluminum layer may be expressed as "pure Al ". Therefore, "pure Al" indicates that the layer included in the gradient functional material is made of aluminum alone, not aluminum having 100% purity.

In one embodiment of the present invention, the dual nanoparticle reinforced aluminum gradient functional material comprises an aluminum layer and a layer containing aluminum and carbon nanotubes.

In another embodiment of the present invention, the dual nanoparticle reinforced aluminum gradient functional material comprises a layer containing an aluminum layer, aluminum and carbon nanotubes, and a layer containing aluminum, carbon nanotubes and nano SiC.

In another embodiment of the present invention, the dual nanoparticle reinforced aluminum gradient functional material comprises a layer comprising an aluminum layer, aluminum and carbon nanotubes, and a layer comprising aluminum, carbon nanotubes and nano SiC, It can be.

In another embodiment of the present invention, the dual nanoparticle reinforced aluminum gradient functional material comprises a layer containing aluminum, carbon nanotubes and nano SiC, a layer containing an aluminum layer, aluminum and carbon nanotubes, Nanotubes and layers containing nano SiC may be stacked in this order.

In another embodiment of the present invention, the dual nanoparticle reinforced aluminum gradient functional material comprises a layer containing aluminum and carbon nanotubes, an aluminum layer, and at least one layer containing aluminum, carbon nanotubes and nano SiC They may be stacked in order.

In another embodiment of the present invention, the dual nanoparticle reinforced aluminum gradient functional material comprises an aluminum layer and at least one layer comprising aluminum, carbon nanotubes and nano SiC, wherein the aluminum, carbon nanotubes and / The layer containing nano SiC may be one or more layers laminated on one or both sides of the aluminum layer.

In the double nanoparticle reinforced inclined functional composite according to one embodiment of the present invention, the carbon nanotube content of the carbon nanotube-containing layer has a range of 0.5 to 50 vol.% Based on the total volume of the layer .

According to another embodiment of the present invention, there is provided a dual nanoparticle reinforced inclined functional composite material comprising aluminum and carbon nanotubes, wherein the layer containing or not containing nano SiC comprises 50 to 99.5 vol.% Of aluminum, 0.5 to 50 vol.% Of the tube and 0 to 30 vol.% Of the nano SiC.

In the present invention, when the double nanoparticle reinforcing gradient functional composite comprises two or more layers containing aluminum, carbon nanotubes, and nano SiC, the two or more layers are separated from the aluminum layer and the carbon nanotube content May be stacked in an increasing or decreasing order.

The present invention also provides a dual nanoparticle reinforced stiffening composite material, which comprises laminating and sintering an aluminum powder, a composite powder of aluminum and carbon nanotubes, a composite powder in which aluminum, carbon nanotube and nano SiC particles are uniformly dispersed, And a method for producing the same.

In the embodiments of the present invention, the average diameters are 20 nm and 100 nm, and the lengths are 10 μm and 20 μm, respectively. However, this is according to one embodiment of the present invention, and a commercially available carbon nanotube It may be used.

In the embodiment of the present invention, the size of the aluminum powder is reduced to 63 μm or less. However, any aluminum powder may be used.

In the present invention, nano-sized silicon carbide powder is used. The nano silicon carbide (hereinafter also referred to as " nSiC ") has a high tensile strength, sharpness, constant conductivity and heat conductivity, high hardness and high fire resistance, high thermal shock resistance, high temperature properties and chemical stability, Or as a refractory material. In the present invention, the average particle size of nSiC is preferably in the range of 10 to 50 nm, and most preferably in the range of 20 to 30 nm. The smaller the size of the SiC powder is, the better the dispersion effect is. However, when the size is several nanometers, the increase of the surface area is undesirable because it causes cohesion between the insert particles.

In the present invention, the thickness of the double nanoparticle reinforced aluminum gradient functional material may range from a few centimeters to a few meters, depending on the application of the material. For example, when the inclined functional material according to the present invention is used as a barrier, the total thickness may be several meters. The number of layers and the thickness of each layer may also be adjusted according to the needs of the field in which the material is used.

The double nanoparticle reinforced aluminum tilted functional material according to the present invention can be produced by the following method.

First, the composite powder is obtained by mixing aluminum (Al) powder, carbon nanotube and nSiC, and milling, preferably milling, with an oil mill. The balls and the powder are milled for 0.5 to 20 hours at a rate of 5 to 15: 1 at 200 to 500 r / min in an inert atmosphere such as nitrogen or argon atmosphere to uniformly mix aluminum, carbon nanotubes, and nSiC To obtain a dispersed composite powder. As the process control agent, at least one organic solvent selected from the group consisting of hexane, hexane and alcohol may be used in an amount of 0 to 30 wt% based on the total weight of the powder.

nSiC is known to have high strength, high temperature properties and chemical stability. The n-SiC-added Al-CNT composite powder can enhance the mechanical properties by simultaneously strengthening and dispersing fine particles by homogeneously dispersed nSiC particles as well as strengthening by CNT. Therefore, in the present invention, the composite powder can be prepared by selecting the mixing ratio of Al-CNT-nSiC, and laminated in a multi-layered structure capable of exhibiting a warp function, so that the composite material can exhibit properties suitable for the field in which the composite material is used.

In the present invention, a composite powder of aluminum-carbon nanotube-nano SiC (Al-CNT-nSiC) is obtained by the above-described process, and a pure aluminum powder and a desired ratio of Al-CNT-nSiC composite powder are selected, By adjusting the concentration gradient, the layer thickness and the number of layers, it is possible to obtain a gradient functional material by laminating and sintering.

For sintering, a discharge plasma sintering or hot pressing sintering apparatus can be used, but any sintering apparatus may be used as long as the same object can be achieved. When it is necessary to precisely sinter in a short time, it is preferable to use a discharge plasma sintering apparatus. The sintering temperature is 400 to 600 ° C and the pressure is 30 to 100 MPa.

Example

Hereinafter, the present invention will be described in more detail with reference to examples. However, the embodiments are illustrative of the present invention and are not intended to limit the scope of the present invention.

1. Materials

Two types of multi-walled carbon nanotubes (diameter 20 nm, length 10 μm and diameter 100 nm, length 20 μm), gas-atomizing aluminum powder (ECKA granules, purity 99.5% 63 μm or less) and nano silicon carbide were used as starting materials.

The nanosilicon carbide particles were prepared with an average particle size of 20-30 nm by inductively coupled plasma.

2. Distributed

10 mm 볼과 분말의 비율을 10:1로 사용하고, 공정제어제로서 분말의 총 중량에 대해 헵탄 20 중량%를 사용하였다.Al powder, carbon nanotubes (100 nm) and nanosilicon carbide in a planetary mill for 3 hours at 360 r / min in an argon atmosphere

The ratio of 10 mm balls to powder was used as 10: 1, and 20 wt% of heptane was used as the process control agent based on the total weight of the powder.

Composite powders were prepared with compositions of Al-10 vol.% CNT-30 vol.% NSiC and Al-30 vol.% CNT-10 vol.% NSiC.

The composite powder was stabilized in a glove box filled with argon gas and then Al-10 vol.% CNT, pure Al, Al-10 vol.% CNT-30 vol.% NSiC, Al-30 vol.% CNT-10 vol.% nSiC, and sintered in a discharge plasma sintering apparatus.

Sintering was carried out at a maximum temperature of 600 ° C for 20 minutes, a temperature increase of 40 ° C per minute, and a pressure of 50 MPa. The inclined composite material had a diameter of 15 mm and a thickness of about 10 to 20 mm depending on the number of layers.

Archimedes' principle was to measure the density of the gradient functional complex according to the ISO standard. In addition, the micro Vickers hardness was measured under the condition of load 20, 0.02 kg for 15 seconds according to EN ISO standard. At least 5 measurements were made per sample.

The microstructure of the composite material was analyzed by high resolution cold field scanning electron microscopy (Hitachi, HRCFE-SEM S-4800) and high resolution transmission electron microscopy (HR-TEM, Hitachi, Japan) diffraction patterns, SADP).

Using a linear detector (X'Celerator) in the 2 [theta] range from 20 [deg.] To 80 [deg.] Using an X'Pert Pro diffractometer (PANAlytical) with a Cu- K alpha radiation source ([lambda] = 0.15148 nm, 35 kV and 40 mA) X-ray diffraction (XRD) patterns were measured. The step size was 0.02 ° and the scan speed was 0.05 ° / s. The grain size was calculated by the Scherrer equation. To evaluate the disorder in the CNT, a spectral analysis was performed with a red He-Ne ion laser (Leica) having a wavelength of 633 nm.

The FE-SEM photograph of the raw Al particles shows irregular shape and shows various size distributions (Fig. 1 (a)). The nSiC dispersant shows an aspect ratio close to 1 and an overall spherical shape (Fig. 1 (b)). As shown in FIG. 1 (c), the CNT having an average diameter of 20 nm was extremely agglomerated and the thickness of one side of the multiwall was about 2 nm. The surfaces of many CNTs were covered with amorphous impurities (black arrows in Figure 1 (c)). As shown in Fig. 1 (d), CNTs with an average diameter of 100 nm were highly crystalline and had thick wall structures of various sizes, but some showed disordered regions (black arrows).

As shown in Fig. 2, the ball milled composite powder exhibited various particle size distributions. Some Al composites were generated by the re-agglomeration of finely milled particles (Fig. 2 (a) and (b)). Overall, it was very difficult to observe CNT particles in a mixed powder containing Al and 10 vol.% CNT (average diameter 20 nm) after ball milling, Some CNTs were observed on Al particles.

In the case of Al-10 vol.% CNT-30 vol.% NSiC composite powder, the Al particles became finer after ball milling as seen in FIGS. 2 (d), (e) and (f) CNT (average diameter 100 nm) was well dispersed in Al particles with nSiC dispersant. It is estimated that the milling energy and lubricating effect are higher than that of CNT - only composite powder.

As shown in FIG. 2 (g), when the content of CNT is higher or lower than that of Al-10 vol.% CNT composite powder having pure Al particles, Al-10 vol.% CNT and 30 vol.% NSiC Many large Al particles were observed in the case of nSiC added composite powders.

Carbon isotopes are often used as lubricants (solids, liquids, pastes), and carbon nanotubes are one of the carbon isotopes. For this reason, the lubrication effect can be increased, and as the amount of the carbon nanotubes to be added increases, fine particles can be produced. However, when a large amount of carbon nanotubes are added, the particle size is larger than when a small amount of carbon nanotubes is added unlike the case of the generation of fine particles. This phenomenon is due to the re-agglomeration of the fine particles produced during the ball milling process, which means that the lubrication effect of the carbon nanotubes also serves as an efficient process control agent for the formation of fine particles. Therefore, the lubrication effects of carbon nanotubes in the ball milling process must be carefully controlled.

Most of the aluminum particles are surrounded by well-dispersed carbon nanotubes, and the shape of the carbon nanotubes is well maintained and very easily observed (Fig. 2h, 2i). In addition, carbon nanotubes were well dispersed regardless of the amount of nSiC added.

Regardless of the composition shown in Table 1, the composite powder was densely sintered after the discharge plasma sintering process. Table 1 shows physical properties of a pure aluminum sintered body and the Al-CNT-nSiC gradient functional composite material according to the present invention.

sample
Density (g / cm3) 占 0.01
Vickers hardness
(HV20) ± 1,2 Raman Spectrum
I _D / I _G ratio Theoretical value Experimental value Pure Al bulk 2.70 2.70 42.1 - Al-10 vol.% CNT 2.63 2.63 102.0 1.19 (raw 20 nm CNT: 1.18) Al-10 vol.% CNT-30 vol.% NSiC 2.78 2.78 154.3 0.94 (raw material 100 nm CNT: 0.23) Al-30 vol.% CNT-10 vol.% NSiC 2.54 2.54 132.6 0.41

As can be seen in Table 1, the Vickers hardness value of the composite material is found to be almost four times higher than that of pure Al.

 The specimen with 30% nSiC shows the highest hardness value. This indicates that nSiC has a greater influence on hardness improvement between CNT and nSiC, which shows that nSiC plays an important role not only in the role of dispersion medium but also in hardness.

3 is a photograph of a gradient functional material obtained by laminating a dual particle reinforced composite powder in various layers. Two, three, and four layers of graded functional materials were prepared with the ball milled composite powder. No microscopic pores are found in inclined composite materials. By the method proposed in the present invention, it is possible to design and manufacture inclined functional materials of various compositions and number of layers. Also, the constituent materials of the gradient functional layer are not limited to the aluminum base, but can also be applied based on other metal materials.

As shown in Fig. 4 (a-c), the interface of the gradient functional layer is tightly bonded regardless of the composition. Each layer showed different microstructure (Fig. 4 (d-g)). Several black spots are found in some areas of the surface of the gradient functional layer, but this is not porosity. This was not found before the chemical etching, but seems to have been made by etching, given the appearance after the etching operation. The density measurements measured before the etching treatment in Table 1 also support this.

The graded functional layer looks different in color due to the refraction of light. The dual particle reinforced graded functional layer has microstructures aligned in a direction perpendicular to the pressure as shown in Figs. 4 (b) and 4 (c). The aligned microstructure showed the same shape in high aspect ratio carbon nanotube composite powder.

A small number of thick SiC particles observed in some areas are due to the precursors used in the production of nSiC. The interfacial bonding of the gradient functional layer is well established and there are no severe microcracks or pores. Thus, it can be seen that the discharge plasma sintering method is suitable as a process for manufacturing a bulk gradient functional layer.

In order to observe the pore and bonding state of the nano region of the gradient functional layer, it was analyzed by TEM. FIG. 5 clearly shows another microstructure firmly bonded to the Al and Al-10 vol.% CNT interfaces without nanoclaws. However, several pores were observed at the Al and Al-10 vol.% CNT interfaces (Fig. 5 (c) and (d)). These pores are observed in the form of general ion milling in the ion milled region and thus appear to have been made by ion milling during preparation of the sample (Fig. 5 (c) and (d)). The majority of the surface between Al and Al-10 vol.% Is covered with a very thin, well-bonded amorphous Al oxide film (Fig. 5 (e)).

In the Al-10 vol.% CNT bases, not only well-dispersed CNTs in the Al matrix but also non-decomposed CNTs and broken CNTs were observed. In FIG. 5 (f), some aluminum carbide (Al ₄ C ₃ ) was observed with a size similar to CNT.

Since the powder after the ball milling process is in a highly unstable energy state (with high re-reaction latent energies) it appears to have formed in the discharge plasma sintering process. Nanocrystalline Al ₄ C ₃ was produced because the discharge plasma process temperature was sufficient to provide re-reaction between aluminum and some disordered carbon nanotubes. In general, Al ₄ C ₃ is considered to be an undesirable compound due to its brittleness and hygroscopicity in structural materials. However, if a small amount of nano-sized Al ₄ C ₃ is in a consistently well dispersed state, it can transfer stress through the chemically bound interface between the Al matrix and the strengthening agent. The transfer of stress through carbide can be explained by the results of other researchers, yet it must be carefully proven.

The interface between Al and Al-10 vol.% CNT-30 vol.% NSiC has similar behavior to the interface between Al and Al-10 vol.% CNT, and more interesting microstructure see. It is difficult to distinguish the interface because the interface of each layer is perfectly combined as if it is recognized as a single material (Fig. 6 (a)).

The interface edge portion of Fig. 6 (a) shows a general ion milled pattern, which demonstrates strong interfacial bonding and similar properties. Some generated nano-sized Al ₄ C ₃ is observed in Al particles (Fig. 6 (b)). Al ₄ C ₃ is also embedded at each interface connected to the Al base (Fig. 6 (c)). Al ₄ C ₃ nanotyde rod structures show stress transfer between the matrix and the reinforcements and have been studied. The CNT and nSiC mixtures were located between the Al particles regardless of the composition of the bulk material, but in some nSiC zones, nanometer dispersion was observed at the interface (Fig. 6 (d) and (e)). The boundary line of the white dotted line in Fig. 6 (e) shows that a part of the surface of the Al particles is covered with nSiC having a thickness of 100-200 mm. Because nSiC plays a key role in protecting the direct contact between disordered CNT and Al particles by reducing the potential reactivity, only a small amount of Al ₄ C ₃ is observed despite the high carbon environment (10 and 30 vol.% CNT) . In the sintered body, nSiC particles are well dispersed at most interface of CNT like composite powder. In FIG. 6 (f), black arrows were observed by observing some modified or intact forms of carbon nanotubes in an Al matrix. However, among the layers strengthened with the double nanoparticles, Al mainly composed of Al-nSiC and CNT, Al-nSiC-Al and Al mixed with Al-nSiC-nSiC and CNT appear.

D band and graphite peak G band due to defects of each layer and CNT of the gradient functional complex were analyzed by Raman spectroscopy. The 100 nm CNT showed a lower defect peak intensity than the 20 nm CNT (Figs. 7 (a) and (b)). Generally, G peaks appear in all graphite materials, and D peaks are easily observed in defective CNTs or graphite. Also, the intensity (ID) / intensity (IG) ratio of D is commonly used as a direct measure of the quality of CNTs. The ID / IG ratios of the average diameter of 100 nm and 20 nm CNT were 0.23 and 1.18, respectively, as shown in Table 1. This indicated that the average diameter CNT of 100 nm was better than the CNT of 20 nm.

The Raman analysis results of the graded functional layer composite show that it has a pattern similar to pure CNT except for Al-10 vol.% CNT-30 vol.% NSiC containing a large amount of nSiC (FIG. 7 (d)). This is explained for two reasons. First, the high strength of nSiC transfers relatively effective impact energy to carbon nanotubes in the ball milling process. Therefore, the nSiC contents show differences in the breakdown of graphite region of carbon nanotubes and the formation of amorphous carbon impurities. Therefore, a low G peak is observed in a sample containing a large amount of nSiC (Fig. 7 (d)). The second possibility is that the carbon nanotubes in the Raman spectroscopic analysis may have relatively low G peaks due to the addition of a small amount of carbon nanotubes as much as a large amount of nSiC.

In Table 1, the ID / IG ratio supports the same result, which is believed to be due to two complex influences as described above. The ID / IG ratio of the 30 vol.% CNT sample was twice as low as that of 10 vol.% CNT (Table 1). The G peak of the Al-10 vol.% CNT sample shifted slightly with a high residual stress (Fig. 7 (c)). As a result of the ID / IG ratio, the degree of the defect was not seriously affected in the 20 nm carbon nanotube under the experimental milling condition, but it had a great influence on the carbon nanotube having the average diameter of 100 nm. Nevertheless, the ID / IG ratio of the sample to which 100 nm carbon nanotubes are added is lower than that of the sample to which the 20 nm carbon nanotubes are added.

Although Al ₄ C ₃ was found in TEM photographs (Figures 5 and 6), it was formed with a relatively small amount of nano-size and no diffraction pattern (Figure 8) was found in XRD due to equipment resolution limitations. On the other hand, the C peak was observed in proportion to the addition amount of the carbon nanotubes as well as the Al and SiC peaks in XRD.

As described above, those skilled in the art will appreciate that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. It is therefore to be understood that the above-described embodiments are to be considered in all respects as illustrative and not restrictive. The scope of the present invention is defined by the appended claims rather than the detailed description and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included within the scope of the present invention.

Claims (5)

An aluminum layer;
A layer containing aluminum and carbon nanotubes; And
At least one layer containing aluminum, carbon nanotubes and nano SiC
And a second sintered body,
The layer containing aluminum, carbon nanotube and nano SiC is laminated on at least one surface or both surfaces of the aluminum layer, and aluminum and carbon nanotubes are uniformly dispersed in each layer doing,
Dual Nanoparticle Reinforced Aluminum Alloy Functional Material.
The method according to claim 1,
Aluminum layer,
A layer containing aluminum and carbon nanotubes, and
Aluminum, carbon nanotubes, and nano SiC, in the order of one or more layers.
3. The method of claim 2,
Wherein one or more layers comprising aluminum, carbon nanotubes and nano SiC are laminated on one side of the aluminum layer not in contact with the layer containing aluminum and carbon nanotubes.
The method according to claim 1,
A layer containing aluminum and carbon nanotubes,
An aluminum layer, and
Aluminum, carbon nanotubes, and nano SiC, in the order of one or more layers.
5. The method according to any one of claims 1 to 4,
Wherein the two or more layers are laminated in the order of increasing or decreasing carbon nanotube content as they move away from the aluminum layer, Reinforced aluminum graded functional materials.

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