KR101143888B1 - The method for preparation of metal matrix powder with mechanical alloying and metal matrix powder thereby - Google Patents

Abstract

The present invention relates to a method for producing a metal composite powder using a mechanical activation method and to a metal composite powder prepared according to the above, and more particularly to mixing aluminum and the reinforcement phase powder to produce aluminum-reinforced powder by mechanical milling. Step (step 1); Melting the aluminum ingot and adding and stirring the aluminum-enhanced powder prepared in step 1 to prepare a molten metal (step 2); And a method for preparing a metal composite powder using a mechanical activation method comprising spraying the molten metal prepared in step 2 together with a gas (step 3), and a metal composite powder prepared by the above method. will be. The method for producing a metal composite powder using the mechanical activation method according to the present invention improves the dispersibility in the metal composite powder by milling aluminum and the reinforcement phase powder as a mechanical activation method, and intra-granular by gas spraying. By dispersing the reinforcing phase in the to increase the mechanical strength and to enable the mass production of metal composite powder, it can be usefully used to prepare a metal composite powder.

Mechanical activation method, aluminum, reinforced phase, molten metal, spray, metal composite powder

Description

The method for preparation of metal matrix powder with mechanical alloying and metal matrix powder according to the present invention

The present invention relates to a method for producing a metal composite powder using a mechanical activation method and to a metal composite powder prepared accordingly.

In general, as a method of manufacturing a metal powder, a grinding method of pulverizing a solid metal, a wet method through a chemical method such as precipitation, and a spraying method of melting a metal material and spraying using a spray nozzle are used. In the above method, the spraying method may be classified into a water spray method using a liquid such as water and a gas spray method using a gas, depending on the cooling medium used.

In the conventional method of manufacturing metal powder by gas atomization, a metal powder is prepared by injecting an inert gas such as argon or nitrogen at room temperature while flowing molten metal through an injection nozzle, and the particle size of the manufactured metal powder. Was formed on the average of about 100 μm.

Metals have low melting points such as zinc (Zn), aluminum (Al), tin (Sn), and stainless steel, copper (Cu), iron (Fe), nickel (Ni), and cobalt (Co) depending on the melting temperature. It can be divided into a metal having a high melting point or a multi-element alloy and the like. On the other hand, the metal materials classified into various types as described above include a reinforcing phase to improve the properties of the metal material. In this way, the metal material containing the reinforcing phase is mainly added to the molten casting method. It is manufactured through. However, the metal material manufactured through the melt casting method as described above has a high possibility of separation of the reinforcement phase along the interface, which makes it difficult to process the actual shape of the manufactured product, and has a low melting point matrix phase material and a high melting point. A separate melt mixing process is added to mix the phase materials.

In addition, the molten cast metal material including the mixing process as described above, when the reinforcement phase and the matrix phase is mixed, the reinforcement phase is agglomerated to generate a non-uniform distribution, and thus the amount, size, shape, distribution, etc. of the reinforcement phase There is a problem that is difficult to control, and there is a problem that the size of the reinforcing phase-containing metal material is also difficult to control. In addition, the wettability of the reinforcement phase and the matrix phase is low, there is a problem of lowering the characteristics of the composite material due to the degradation of the interfacial properties.

Therefore, the inventors of the present invention studied the manufacturing method of the metal composite powder to improve the dispersibility of the aluminum-reinforced phase in the metal composite powder by using the mechanical activation method and to disperse the reinforced phase in the mouth of the matrix by using the gas spraying method. The manufacturing method of metal composite powder was developed and the present invention was completed.

An object of the present invention to provide a method for producing a metal composite powder using a mechanical activation method.

Another object of the present invention is to provide a metal composite powder produced by the above method.

In order to achieve the above object, the present invention comprises the steps of preparing an aluminum-enhanced powder by mechanical milling after mixing aluminum and the reinforcement phase powder (step 1); Melting the aluminum ingot and adding and stirring the aluminum-enhanced powder prepared in step 1 to prepare a molten metal (step 2); And it provides a method for producing a metal composite powder using a mechanical activation method comprising the step (step 3) of preparing a metal composite powder by spraying the molten metal prepared in step 2 with the gas.

In addition, the present invention after mixing the aluminum and the reinforcement phase powder to produce an aluminum-enhanced powder by mechanical milling, after melting the aluminum ingot to add the aluminum-enhanced powder prepared above and stirred to prepare a molten metal It provides a metal composite powder prepared by spraying with a gas.

The method for producing a metal composite powder using the mechanical activation method according to the present invention improves the dispersibility in the metal composite powder by milling aluminum and the reinforcement phase powder as a mechanical activation method, and intra-granular by gas spraying. By dispersing the reinforcing phase in the to increase the mechanical strength and to enable the mass production of metal composite powder, it can be usefully used to prepare a metal composite powder.

The present invention

Mixing the aluminum and the reinforcement phase powder and then preparing the aluminum-enhanced phase powder by mechanical milling (step 1);

Melting the aluminum ingot and adding and stirring the aluminum-enhanced powder prepared in step 1 to prepare a molten metal (step 2); And

It provides a method for producing a metal composite powder using a mechanical activation method comprising the step (step 3) of preparing a metal composite powder by spraying the molten metal prepared in step 2 with the gas.

Hereinafter, the manufacturing method according to the present invention will be described in detail step by step.

In the method for producing a metal composite powder according to the present invention, step 1 is a step of preparing aluminum-reinforced powder by mechanical milling of aluminum and the reinforcement powder (see FIG. 1).

At this time, the reinforcement phase may be AlN, TiC and SiC, and the like, and the mechanical milling is performed for about 30 minutes to manufacture a plate using a low-energy ball mill and a stainless steel ball, which is a horizontal mill, to prepare a spherical powder In order to perform the milling for about 5 hours, RPM and milling time can be adjusted according to the low energy and high energy milling methods. The mechanical milling allows the reinforcement phase to be uniformly distributed in the aluminum substrate.

In addition, the size of the aluminum-enhanced powder prepared by the mechanical milling is prepared in the shape of a plate or sphere in the range of 10-5000 μm, and the particle size of the reinforcing phase present in the aluminum powder is in the range of 0.001-50 μm.

Next, in the method for producing a metal composite powder according to the present invention, step 2 is a step of melting the aluminum ingot and then adding the aluminum-enhanced powder prepared in step 1 and stirring to prepare a molten metal (FIG. 2). Reference).

At this time, the reinforcing phase present in the aluminum-enhanced powder of step 2 is preferably present in 0.1 to 70% by volume relative to the Al ingot. If the aluminum-enhanced powder is less than 0.1% by volume, there is a problem in that tensile strength and wear resistance are not improved. When the aluminum-enhanced powder is more than 70% by volume, the viscosity of the molten metal is increased so that the metal composite powder is not prepared by gas spraying. There is no problem.

In addition, the addition of the aluminum-enhanced powder of step 2 is preferably added at a temperature at which the crystal structure generated in the aluminum-enhanced powder is maintained after melting the aluminum ingot.

Furthermore, the molten metal of step 2 may further include a step of raising the temperature to 700 to 800 ° C. for 5 to 30 minutes. By performing the above process, the viscosity of the melt is lowered, so that the gas spraying is performed smoothly, the reinforcement phase can be prevented from segregating and decomposing.

Next, in the method for producing a metal composite powder according to the present invention, step 3 is a step of preparing a metal composite powder by spraying the molten metal prepared in the step 2 with a gas.

The gas of step 3 is preferably a mixed gas consisting of nitrogen and oxygen in a volume fraction of 7-9: 3-1.

In addition, the spraying of the step 3 is preferably carried out at a pressure of 5-100 bar. If the pressure is less than 5 bar, there is a problem that the size of the prepared metal composite powder is increased and the particle size distribution is widened. If the pressure is greater than 100 bar, the powder is manufactured in the form of flakes, thereby reducing the powder manufacturing efficiency. there is a problem.

Furthermore, in the present invention, after mixing aluminum and the reinforcement phase powder, the aluminum-reinforced phase powder is manufactured by mechanical milling, the aluminum ingot is melted, and the aluminum-reinforced phase powder prepared above is added and stirred to prepare a molten metal. Provided is a metal composite powder prepared by spraying with gas.

In addition,

Mixing the aluminum and the reinforcement phase powder and then preparing the aluminum-enhanced phase powder by mechanical milling (step A);

Preparing an molten metal by heating and stirring the aluminum-enhanced powder prepared in Step A at the bottom of the aluminum base material after Al-foiling (step B); And

It provides a method for producing a metal composite powder using a mechanical activation method comprising the step (step C) of preparing a metal composite powder by spraying the melt prepared in step B with a gas.

Hereinafter, the manufacturing method of the present invention will be described in detail step by step.

In the method for producing a metal composite powder according to the present invention, step A is a step of preparing aluminum-reinforced powder by mechanical milling after mixing aluminum and reinforcement powder (see FIG. 1).

At this time, the reinforcement phase may be AlN, TiC and SiC, and the like, the mechanical milling is performed for about 30 minutes to manufacture a plate using a low energy ball mill and a stainless steel ball, the mechanical mill is a horizontal mill, spherical In order to produce the powder, milling can be carried out for about 5 hours, RPM and milling time can be controlled according to low energy milling and high energy milling, and the mechanical milling ensures that the reinforcement phase is uniformly distributed in the aluminum substrate.

In addition, the size of the aluminum-enhanced powder prepared by the mechanical milling is prepared in the shape of a plate or sphere in the range of 10-5000 μm, and the particle size of the reinforcing phase present in the aluminum powder is in the range of 0.001-50 μm.

In the method for producing a metal composite powder according to the present invention, step B is to charge the aluminum-enhanced powder prepared in step A at the bottom of the aluminum base material after Al-foiling, and then heated and stirred to prepare a molten metal. Step (see FIG. 3).

At this time, the reinforcement phase present in the aluminum-enhanced phase powder of step B is preferably present in 0.1 to 70% by volume relative to the Al ingot. If the aluminum-enhanced powder is less than 0.1% by volume, there is a problem in that tensile strength and wear resistance are not improved. When the aluminum-enhanced powder is more than 70% by volume, the viscosity of the molten metal is increased so that the metal composite powder is not prepared by gas spraying. There is no problem.

In addition, the step B may further include a step of raising the aluminum base material for 5 to 30 minutes further to the 700 ~ 800 ℃ temperature range after melting. By performing the above process, the viscosity of the melt is lowered, so that the gas spraying is performed smoothly, the reinforcement phase can be prevented from segregating and decomposing.

Next, in the method for producing a metal composite powder according to the present invention, step C is a step of preparing a metal composite powder by spraying the molten metal prepared in the step B with a gas.

The gas of step C is preferably a mixed gas consisting of nitrogen and oxygen in a volume fraction of 7-9: 3-1.

In addition, the spraying of the step C is preferably carried out at a pressure of 5-100 bar. If the pressure is less than 5 bar, there is a problem that the size of the prepared metal composite powder is increased and the particle size distribution is widened. If the pressure is greater than 100 bar, the powder is manufactured in the form of flakes, thereby reducing the powder manufacturing efficiency. there is a problem.

Furthermore, the present invention mixes aluminum and the reinforcement phase powder, and then prepares the aluminum-reinforced phase powder by mechanical milling, and loads the aluminum-reinforced phase powder prepared above into Al-foiling after charging to the bottom of the aluminum base material. It provides a metal composite powder prepared by heating and stirring to prepare a molten metal and then sprayed with a gas.

Therefore, the method for producing a metal composite powder using the mechanical activation method according to the present invention improves the dispersibility in the metal composite powder by milling the aluminum and the reinforcement powder into a mechanical activation method, and the intragranular aluminum by the gas spraying method (intra- Dispersing the reinforcing phase in granular) increases the mechanical strength and enables the mass production of the metal composite powder, it can be usefully used to prepare the metal composite powder.

Method for producing a metal composite powder using the mechanical activation method according to the invention can be carried out with the manufacturing apparatus shown in Figures 4 and 5, the manufacturing method of the present invention is not limited to being manufactured only by the manufacturing apparatus. . Referring to FIG. 4, aluminum and powdered phase powder may be performed by the apparatus of FIG. 4. 5, a crucible 120 and a heater 140 for melting aluminum-enhanced powder and aluminum ingot manufactured by mechanical milling are provided in the upper chamber 100, and the crucible 120 is provided. At the upper side of the aluminum-enhanced powder and the ingot is provided with a receiving means 500 is provided. The crucible 120 is formed so that the upper side is opened, the receiving area is narrowed from the upper side to the lower side, the spray nozzle 300 is connected to the lower end. In addition, the outside of the crucible 120 is provided with a heater for heating the crucible, so that the aluminum-enhanced powder and the aluminum ingot accommodated therein can be heated together with the crucible 120. The feeding means 500 includes a receiving part 520 and an operation part 540, and is formed in a cylindrical shape and the receiving part 520 in which aluminum-enhanced powder and ingot are accommodated therein is one direction from the center of the crucible. Rotating shaft is formed on the biased portion is formed to be rotated about the rotating shaft. On one side of the body of the accommodating part 520 is an operation part 540 which inclines the accommodating part 520 in one direction by a user operation so that the ingot accommodated in the accommodating part 520 can be introduced into the crucible 120. Connected. That is, the operation unit 540 is one end is connected to the receiving portion 520, the other end is formed so as to be exposed to the outside of the upper chamber 100, the user grips the other end exposed to the receiving portion 520 ) Rises in the direction of gripping about the rotation axis, and the ingot accommodated therein is introduced into the crucible 120. In this case, the user may be provided with a motor and an operation switch to operate the operation switch, so that the accommodation portion 520 may be configured to be inclined in one direction by the operation of the motor. Meanwhile, inside the crucible 120, aluminum-enhanced powder and aluminum ingot are accommodated and heated by the heater 140 to be molten, and the aluminum-enhanced powder and ingot are added to the molten metal to be stirred. A part of the stirring means 400 is accommodated. The stirring means 400 is provided on one side of the upper chamber 100 and is connected to the stirring motor 420 to generate a rotational force, and the rotating shaft of the stirring motor 420, accommodated in the crucible 120 is molten That is, the molten aluminum-enhanced powder and the aluminum ingot is configured to include an impeller 440 that rotates to be stirred. The spray nozzle 300 is connected to the lower end of the crucible 120 is produced in a powder form while the molten metal is injected into the lower chamber 200 with a high-pressure gas, it is recovered in the lower chamber 200.

Hereinafter, the present invention will be described in more detail by the following examples. However, the following examples are merely to illustrate the invention, the content of the present invention is not limited by the following examples.

≪ Example 1 >

After mixing aluminum metal and TiC powder, the mechanical milling was performed for about 30 minutes in order to prepare a plate using a low-energy ball mill (ZoZ GmbH, Smoloyer, Germany) and a stainless steel ball. Milling was carried out for about 5 hours to produce. After the Al-TiC powder was manufactured by the mechanical milling, the aluminum ingot was melted, the Al-TiC powder prepared above was added and stirred, and the molten metal temperature was rapidly increased to 750 ° C. within 10 minutes. While spraying the mixed molten metal through a nozzle having a diameter of 3 mm, nitrogen and oxygen were injected into the molten metal at a pressure of 20 bar by using a mixed gas having a volume fraction of 8: 2 to prepare a metal composite powder.

analysis

One. Al , TiC  Manufactured by powder and mechanical activation Al - TiC  Surface analysis of composite powder

In order to analyze the surface of Al, TiC powder and Al-TiC powder prepared by mechanical activation method, it was analyzed by scanning electron microscope (SEM, JEOL, 6500F), and the results are shown in FIG.

Referring to Figure 6, Figure 6 (a) shows the aluminum surface, (b) shows the surface of the TiC powder, (c) shows the surface of the Al-TiC composite powder prepared by the mechanical activation method.

2. TiC  2% by weight of powder Al  alloy Ingot

Aluminum and powdered powders were prepared by mechanical milling, and aluminum-powdered powders were melted together with aluminum ingots to prepare a molten metal, followed by stirring and solidifying at high speed to prepare an Al alloy ingot containing 2% by weight of TiC powder. , Photographed. An Al alloy ingot containing 2 wt% of the TiC powder is shown in FIG. 7.

3. TiC  Powdered Al  alloy Ingot  Surface and Component Analysis

In order to investigate the surface and composition of Al-TiC alloy ingot prepared by melting aluminum and reinforcement powder by mechanical milling and melting it with aluminum ingot to prepare molten metal, stirring and solidifying at high speed Scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDS) points were analyzed and the results are shown in FIG. 8.

As shown in FIG. 8, it can be seen that the TiC powder is distributed in the Al matrix intra-granular (see FIG. 8 (a)), and it can be seen that Al, Ti, and C are composed of the main component. (See FIG. 8B).

4. TiC  Powdered Al  alloy Ingot  Ingredient analysis

Aluminum-enhanced powder is prepared by mechanical milling and then aluminum-enriched powder is melted together with aluminum ingot to prepare a molten metal, followed by stirring and solidifying at high speed to disperse the energy of Al-TiC alloy ingot. Analysis by type X-ray spectroscopy (EDS) mapping, and the results are shown in FIG.

As shown in Fig. 9, it can be seen that Al, Ti, and C are composed of main components, and a small amount of Si is contained.

1 is a flow chart of the mechanical activation method according to the present invention ((A): raw material (a: Al, b: reinforced phase), (B): mechanical activation (c: reinforced inside the Al by continuous cold press and fracture Phase homogeneous distribution), (C): final material (plate (d) and spherical (e) Al-enhanced powder particles with uniformly distributed reinforcement phase in Al);

2 is a schematic diagram showing a method of adding aluminum-enhanced powder according to the present invention;

3 is a schematic diagram showing a method of adding aluminum-enhanced powder according to the present invention;

4 is a photograph showing a device used in the mechanical activation method according to the present invention;

5 is a schematic view of a manufacturing apparatus that can be used in one embodiment of the present invention;

6 is a scanning electron microscope (SEM) photograph of Al, TiC and Al-TiC powder prepared by the mechanical activation method according to the present invention ((a): Al, (b): TiC, (c): Al-TiC );

7 is an Al alloy ingot picture containing 2% by weight of TiC powder;

FIG. 8 is a graph showing a scanning electron microscope (SEM) photograph (a) and an energy dispersive X-ray spectroscopy (EDS) point of an Al alloy ingot (b); And

9 is a photograph showing the results of analysis by energy dispersive X-ray spectroscopy (EDS) mapping of Al alloy ingot.

<Description of the symbols for the main parts of the drawings>

1: Stirring bar 2: Crucible

3: molten aluminum 4: aluminum-powder powder

5: aluminum base material

100: upper chamber 120: crucible

140: heater 200: lower chamber

300: spray nozzle 400: stirring means

420: stirring motor 440: impeller

500: input means 520: receiving portion

540: control panel

Claims (19)

Mixing aluminum and SiC or TiC reinforcement phase powder to prepare aluminum-enhanced phase powder by mechanical milling (step 1); Melting the aluminum ingot and adding and stirring the aluminum-enhanced powder prepared in step 1 to prepare a molten metal (step 2); And The molten metal prepared in step 2 was raised to a temperature range of 700-800 ° C. for 5 to 30 minutes, and then nitrogen and oxygen were mixed at a pressure of 5 to 100 bar with a mixed gas having a volume fraction of 7 to 9: 3 to 1. A method for producing an aluminum composite powder in which SiC or TiC is dispersed as a reinforcement phase by using a mechanical activation method comprising spraying to produce an aluminum composite powder in which SiC or TiC is dispersed as a reinforcement phase (step 3). delete According to claim 1, wherein the aluminum-enhanced powder prepared in step 1 is a method for producing an aluminum composite powder in which SiC or TiC dispersed as a reinforcement phase, characterized in that the plate-shaped or spherical shape of 10-5000 ㎛ size. The method according to claim 1, wherein the size of the reinforcement phase particles in the aluminum-reinforced powder is in the range of 0.001 to 50 µm. The method of claim 1, wherein in step 2, the reinforcing phase is present in an amount of 0.1 to 70% by volume based on Al ingot. The method of claim 1, wherein the addition of the aluminum-enhanced phase powder of step 2, after the melting of the aluminum ingot is added at a temperature at which the crystal structure produced in the aluminum-enhanced phase powder is maintained SiC or Method for producing aluminum composite powder in which TiC is dispersed. delete delete delete delete delete delete delete delete delete delete delete delete delete

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