KR20170047016A - Powder forming method of aluminum and its alloys - Google Patents

Abstract

The present invention relates to new aluminum and a powder forming method of an aluminum alloy and, more specifically, provides a powder forming method which manufactures a feedstock by mulling aluminum composite powder having aluminum powder, aluminum alloy powder, or a reinforcing material with a thermoplastic organic binder; forms the feedstock of which a shape is complex through powder injection molding, compression molding, or extrusion molding; and then, manufactures a high-density sintered body of which relative density is greater than 96% by performing a single heating process to defat and sinter under an argon gas atmosphere. Through the powder forming method, various precision parts are able to be manufactured.

Description

[0001] Powder forming method of aluminum and aluminum alloys [0002] Powder forming methods of aluminum and its alloys [

The present invention relates to a precise part manufacturing technology for producing a complicated and precise product by a powder molding method such as powder injection molding, warm compression molding, warm extrusion molding and the like using a metal powder of aluminum or an aluminum alloy as a raw material .

The present invention also relates to a precision component manufacturing technique made of a composite material in which a ceramic or other inorganic reinforcement is reinforced with aluminum or an aluminum alloy.

 Powder forming processes for making complex shapes using powder materials and feedstocks made of a sufficient amount of organic binder include various precision forming techniques such as powder injection molding, warm compression molding, and warm extrusion molding. Particularly, as already well known in the prior art, the powder molding method can be economically applied to mass production of a complex shaped product made of various powder materials such as various metals, alloys, intermetallic compounds, ceramics and metal-ceramic composites It is widely used.

Generally, in a conventional powder metallurgy method for forming an aluminum powder material, a relatively coarse powder is used, and a lubricant / surfactant in an amount of about 1.5% by weight or less is mixed with a metal powder for the purpose of reducing friction during molding, . Furthermore, since the conventional powder metallurgy method relies on uniaxial molding, it realizes a comparatively simple shape and induces plastic deformation of the metal powder by molding with high molding pressure, thereby increasing the contact area between neighboring powders, It reduces the amount of pores and promotes densification in the subsequent sintering process. In order to obtain such a high sintered density, the conventional powder metallurgy method usually makes the relative density of the formed body about 90% or more in comparison with the theoretical density.

On the other hand, in the powder injection molding, since a large amount of organic binder corresponding to about 30 to 40 vol% is mixed with the metal powder and the feedstock in an increased fluidity state is used as a raw material, a complicated shaped product is produced. In addition, it is possible to form under much lower pressure conditions than conventional powder metallurgy, and the metal powder in the formed body under molding is subjected to a pressure close to hydrostatic pressure through the organic binder and does not undergo plastic deformation.

Since the metal powder present in the powder injection molded article is in a loosely packed state, sintering is very important for densification by sintering. For this reason, the powder injection molding method uses finer powder than conventional powder metallurgy powder.

At present, powder injection molding has been applied to various metals and alloys including iron-based alloys and stainless steels, and has been positioned as a technology for manufacturing complex and precise shaped products in a thread shape. However, powder injection molding technology has not yet been put into practical use for aluminum and aluminum alloys.

The powder injection molding method for aluminum or aluminum alloy is not industrially used, and the main reason is that it is difficult to produce a high-density sintered body. An oxide film having a thickness of several tens to several hundreds of angstroms is present on the surface of aluminum having high affinity with oxygen.

Since the oxide film on the aluminum surface is chemically very stable, it is practically impossible to reduce the oxygen partial pressure by controlling the melting point of aluminum, that is, a temperature lower than 660 캜. Therefore, aluminum has been recognized as a material unsuitable for powder injection molding applications due to the presence of an oxide coating which acts as an obstacle to the mass transfer between particles to achieve densification.

Generally, one way to remove the oxide film formed on the aluminum powder is to mix an element having a higher oxidation property than aluminum, that is, magnesium powder in the aluminum powder. The added magnesium powder reacts chemically with the oxide film by the chemical reaction of [4Al ₂ O ₃ + 3Mg = 3MgAl ₂ O ₄ + 2Al] during sintering to form magnesium spinel, thereby locally causing reduction of aluminum. This method is very efficient, then nearly all powder metallurgical aluminum alloy known is actually commercially available, for example, Al-Cu-Mg (Germany eka granule's ^{Ecka Alumix ® 13, Ecka Alumix ®} 123; American Cancer eighty-four Ampal 2712, Ampal 2905) (Alumix ^® is a registered trademark of the German eka granules TM) (American aluminum Association corresponds to the discipline alloy classification number AA2024), Al-Mg-Si -Cu ( Germany eka granule's Ecka Alumix ^® 321; AMPAL 6711 American cancer eighty-four) (corresponding to tempered alloy AA6061), Al-Zn-Mg- (Cu) (Germany eka granule's Ecka Alumix ^® 431; AMPAL 7775 American cancer eighty-four) (corresponding to tempered alloy AA7075) or the like are all 0.5% by weight or more A high magnesium component is added.

In the sintering of the aluminum and the alloy powder-formed body produced by the conventional powder metallurgy method, the atmosphere such as nitrogen gas, argon gas, hydrogen gas and vacuum can be used. Among them, the highest sintering density . In fact, nitrogen gas is most widely used as sintering atmosphere gas in industry. Although it is known that the nitrification reaction of Al + (1/2) N ₂ = AlN may occur spontaneously between the aluminum powder and the nitrogen gas, In the powder metallurgy method, the above-mentioned nitriding reaction rarely occurs or extremely limited, which is not a problem.

On the other hand, in the case of using the nitrogen gas as the atmospheric gas in the sintering process, the powder compact according to the present invention, which is made of fine particles having a large specific surface area and a large reactivity, has a porosity of 50% to 10% Nitridation reaction can be a big problem. That is, since the surface of the aluminum particles is exposed to the nitrogen gas to form the aluminum nitride before the sintering reaction between the particles is started during the degreasing process and the heating process at the sintering temperature, it inhibits the mass transfer between the aluminum powders, It is known to interfere with bonding and densification.

Another reason why aluminum powder injection molding technology is more difficult than powder injection molding of other alloys is that the melting temperature of aluminum or the solidus temperature that the liquid phase from the aluminum alloy begins to melt and the solidus temperature starts to increase in the case of iron, stainless steel, nickel, copper, cobalt , And titanium are significantly lower than other alloys. Therefore, it is preferable that the organic binder used in the aluminum powder molding is finished degreasing at a low temperature as much as possible.

Another problem to be solved in the degreasing-sintering process of aluminum moldings containing a large amount of organic binder is the production of aluminum carbide (Al ₄ C ₃ ) by reaction between the organic binder decomposition product and aluminum. Such a carbide phase is brittle and is undesirable because it causes the reaction of moisture with [Al ₄ C ₃ + 6H ₂ O = 2Al ₂ O ₃ + 3CH ₄ ]. To avoid this, it is necessary to use a suitable organic binder composition and strictly control the degreasing process.

Below, we briefly review the literature data that have been published in relation to aluminum powder injection molding so far reported.

In U.S. Patent No. 5,525,292, Nakao et al. Describe a manufacturing process of a component made of an aluminum alloy powder mixed with magnesium as an alloying element and compression-molded so as to have a relative density of 60% to 85% using a nitrogen gas atmosphere . After the addition of magnesium to about 2% and the addition of magnesium in the furnace, sintering is carried out to remove the lubricant, the inside of the furnace is depressurized to induce sublimation of magnesium, followed by introduction of nitrogen gas, And suggest ways to implement it. They argue that sublimated magnesium vapor reacts with nitrogen gas to form Mg ₃ N ₂ , which reacts with aluminum oxide on the surface of aluminum powder to reduce the aluminum oxide coating layer locally to aluminum to improve sinterability.

International Publication No. 2005/066380 discloses that sintering in an atmosphere of nitrogen gas in which the partial pressure of steam is present in the range of about 0.003 kPa to 0.015 kPa is effective for increasing the sintering density of the loosely filled aluminum powder and the alloy powder without externally applying pressure .

In U.S. Patent No. 6,761,852, Yowandian uses a low-temperature process reaction between alumina and a metal flame selected from NaF, MgF ₂ and CaF ₂ to remove the oxide film existing on the surface of the aluminum powder, In order to reduce the size of the system. The aluminum oxide film reacts with the metal fluoride to form a process liquid having a low melting point. As the densification progresses, the metal extrudate is degreased in a solvent and then subjected to thermal degreasing and sintering to produce a high density sintered body having a relative density of 95% And that it is advantageous to sinter in vacuum.

In International Patent Publication No. 2008/017111, Ryu et al. Proposed a method of adding tin of a low melting point as a sintering aid and using a nitrogen gas as an atmospheric gas to charge a magnesium ingot together with an oxygen scavenger to sinter the AA6061 aluminum powder, 2% and a magnesium block as an oxygen scavenger, and sintered in a nitrogen atmosphere to produce a high-density sintered body. Sintered at 620 ° C for 2 hours to obtain a characteristic having a relative density of about 97%, a tensile strength of 165 MPa, an elongation of about 9%, a tensile strength of 300 MPa after T6 artificial aging, and an elongation of 1%.

(L. Acar, HO Gulsoy, "Sintering Parameters and Mechanical Properties of Injection Molded Aluminum Powder", Powder Metallurgy, vol. 54 (No. 2) (2011) pp. 427-431) Aluminum powder with particle size of 7.35 μm (manufactured by Eka Granular Co., Ltd.) and feedstock with a solid phase ratio of 62.5% were injection-molded and subjected to a two-step degreasing process using solvent extraction using heptane and heating degreasing using nitrogen gas It is possible to produce a sintered body having a relative density of 96.2% by sintering under a high-purity nitrogen gas atmosphere at 650 ° C.

Geert et al., International Publication No. 2011/120066 and a paper published in 2012 (C. Giert et al., "Carbon removal as a crucial parameter in the Powder Injection Molding of Aluminum Alloys", Powder Injection Molding International, Vol. . a 6 (No. 4) (2012) pp.65-71) Kata mold ^TM organic binder (Germany BASF's registered trademarks) Al with a known Al-Mg mixed powder, organic binding agent contains a wax and a modified polyacetal in And a powder injection molding technique using a feedstock kneaded with one of the above materials. It has been suggested that dense sintering is achieved when a part of the organic binder is removed by catalytic degreasing using nitric acid or oxalic acid as a catalyst and the remaining organic binder component is sintered in a nitrogen gas containing at least 0.5 vol.% Of oxygen.

As described above, various methods have been proposed for powder injection molding of aluminum and its alloys. However, there is no method for precisely manufacturing a complex shape product while realizing the mechanical characteristics of aluminum alloy so far .

An object of the present invention is to provide a powder injection molding method capable of precisely fabricating precision components of complex shapes made of aluminum or an alloy thereof with a sintered body having a relative density of 96% or more.

Another object of the present invention is to provide a sintered body of high density which is made of aluminum or an alloy thereof by the powder injection molding method and which achieves high density of densification without adding a sintering aid having a low melting point such as tin proposed in the prior art And to provide a degreasing process and a sintering process.

Another object of the present invention is to provide a degreasing process and a sintering process suitable for obtaining a compact and dense sintered body from a formed body made of an aluminum or aluminum alloy composite powder to which a reinforcing material is added to the aluminum or aluminum alloy.

Still another object of the present invention is to provide a method for producing a high-density aluminum or aluminum alloy sintered body and a precise product of an aluminum composite by applying a feedstock for injection molding to low-pressure warm compression molding and extrusion molding.

The technical objects to be achieved by the present invention are not limited to those described above, and other technical subjects not mentioned can be clearly understood by those skilled in the art from the following description.

In order to achieve the above object, the present invention provides a feedstock preparation method for preparing a feedstock by kneading a wax-based thermoplastic organic binder containing an aluminum powder or an aluminum alloy powder and a polyolefin copolymer having a carbonyl group; A shaping step of shaping the feedstock; A degreasing step of removing the organic binder from the molded body; And a sintering step of densifying the degreased sintered body by sintering under an argon gas atmosphere.

Particularly, in the present invention, the degreasing step and the sintering step are performed in a single step in an argon gas atmosphere in the same furnace to remove and sinter the organic binder contained in the formed body.

The present invention also relates to a method of manufacturing an aluminum powder or an aluminum alloy powder, wherein the aluminum powder or the aluminum alloy powder is selected from the group consisting of carbides selected from the group consisting of SiC, B ₄ C, TiC and WC, Si ₃ N ₄ , AIN, TiN, c- Nitrides, oxides selected from the group consisting of Al ₂ O ₃ , SiO ₂ , Y ₂ O ₃ , fly ash and ZrO ₂ , sulfides including MoS ₂ , borides including TiB ₂ , hard compounds including T-800, Or Mo and at least one reinforcement material selected from the group consisting of powder or short fibers selected from the group consisting of whiskers, polycarbonate, graphite, carbon nanotubes, graphene and diamond is provided .

The present invention also provides a sintered body part of an aluminum powder, an aluminum alloy powder or an aluminum matrix composite produced by the above powder forming method, which provides a precision shaped product selected from an impeller, a turbine or a linear motion bearing end cap.

Industrial Applicability According to the present invention, it is possible to provide an aluminum material having many advantages such as low density, high thermal conductivity, electric conductivity, good corrosion resistance, weather resistance and beautiful color as an industrial material and excellent mechanical properties due to high precipitation hardening effect depending on alloying. A powder injection molding technique capable of applying an aluminum alloy is provided.

That is, there is provided a method of manufacturing a high-density sintered product having a relative density of 96% or more by preparing a shaped body having a complicated shape from aluminum or aluminum alloy powder through a powder molding method of the present invention, followed by a degreasing process and a sintering process do.

Further, since the degreasing and sintering of the formed body according to the present invention is performed in a single step to a single step by a single heating schedule, a separate secondary facility such as a solvent extractor or a supercritical fluid degreasing facility is used for degreasing There is no need to introduce, the number of processes can be shortened, the energy can be reduced, and the number of manpower can be reduced, thereby reducing the overall production cost.

Since the sintering auxiliary alloy element having a low melting point such as tin having a low solubility in aluminum is not essentially added to the aluminum or aluminum alloy produced by the powder molding method according to the present invention, it is possible to manufacture a sintered body having more improved mechanical properties .

As described above, the powder molding method according to the present invention can be applied not only to pure aluminum, but also to Al-Cu-Mg- (Mn) series (American Aluminum Association symbol AA2xxx series), Al-Mg-Si series (AA6xxx series) - It is expected to be applicable to almost all commercial aluminum alloys including precipitation hardening type alloy of (Cu) series (AA7xxx series), and it is expected that the industrial ripple effect will be great by manufacturing precision parts required for various applications.

In addition, it is also possible to use carbides such as SiC, B ₄ C, TiC and WC, nitrides such as Si ₃ N ₄ , AlN, TiN, c-BN and h-BN, Al ₂ O ₃ , SiO ₂ , , Oxides such as Y ₂ O ₃ and ZrO ₂ , sulfides such as MoS ₂ , borides including TiB ₂ , hard cobalt heat-resistant alloys such as T-800, powder or short fibers or whiskers of refractory metals such as W and Mo, , Graphite, carbon nanotubes, graphene, diamond, and the like can be manufactured.

Particularly, the powder molding method according to the present invention is applicable not only to powder injection molding but also to warm compression molding and warm extrusion molding.

Therefore, it has a ripple effect of providing new manufacturing technology with high technical, economic and environment-friendly value as a new method in the technology of manufacturing precision shape products of aluminum, aluminum alloy and aluminum matrix composite material.

Figure 1 shows a process flow diagram of the present invention.
(B) sintering at 580 캜 for 0 hours, (c) 590 (b) sintering, and (c) sintering at a temperature of 580 캜 for 0 hours. Fig. 2 is a photograph of the AA6061 alloy tensile test specimen injection body manufactured by the powder injection molding method according to the present invention before and after sintering ° C, 0 hours sintering, (d) 610 ° C, sintering for 2 hours].
FIG. 3 is a graph showing a change in density according to sintering time when the AA6061 alloy powder (curve 1) and the mixed powder (curve 2) injection-molded article were sintered at 610 ° C.
Figure 4 shows the optical microscopic microstructure of the AA6061 alloy injection specimen sintered at 610 ° C.
Fig. 5 shows a test piece obtained by sintering an injection-molded body of AA6061 alloy powder and mixed powder at 610 占 폚 for 3 hours and a test piece which was subjected to solution treatment at 540 占 폚 for 1 hour and artificial aging treatment (T6) at 170 占 폚 for 8 hours Lt; / RTI > at room temperature.
6 is a scanning electron microscope image of a fractured surface of AA6061 alloy powder tensile test specimen prepared by powder injection molding and T6 heat treatment.
FIG. 7 is a graph showing the relationship between an impeller made of a composite powder feedstock prepared by mixing 1 wt% of tin powder and 5 wt% of silicon carbide in a mixed powder of Al-1 wt% Mg-0.5 wt% Si-0.25 wt% Cu aluminum alloy, (A) and sintered body (b).
8 shows a turbine sintered body made of an aluminum-silicon carbide 5 wt% composite powder according to the present invention.
FIG. 9 shows a miniature linear motion bearing end cap injection body (a) and a sintered body (b) made of AA6061 alloy powder according to the present invention, and FIG. 9 (c) This indicates that a dummy bar has been temporarily added to the injection body.

The most problematic point in precisely manufacturing a high-density sintered body by powder injection molding of a part having a complicated shape made of aluminum and its alloy, which is an important aspect of the present invention, is that a low Thereby overcoming sinterability.

As mentioned above, since the aluminum oxide film formed on the surface thereof is very stable thermodynamically, the reduction is hardly possible at a temperature as low as the sintering temperature of aluminum. Further, in the powder injection molding process, the aluminum powder does not undergo plastic deformation Physical breakage of the aluminum oxide coating on the surface of the aluminum powder due to external force can not be taken into consideration because it exists loosely filled in the organic binder.

Nevertheless, sintering occurs in a loosely filled aluminum powder compact because the thermal expansion coefficient of the aluminum oxide is less than about 1/3 of that of aluminum. Therefore, the aluminum oxide powder coating is damaged due to the high thermal expansion of aluminum during the heating process, It is considered that densification occurs by the phenomenon of mass transfer between adjacent powders through metal aluminum. This effect is more effective as the sintering temperature is higher.

Of course, it is very important to control the oxygen content in the raw powder of the aluminum powder to be as low as possible, and it is advantageous to use the powder produced by the gas spraying method having a lower oxygen content than the powder prepared by the air atomizing method.

Also, as mentioned above, the addition of an alloying element which causes a partial reaction by chemical reaction with an oxide film on the surface of the aluminum powder on the surface of the aluminum powder can be an effective means for improving the sinterability of the aluminum alloy.

In order to fully utilize the fresh metal aluminum, which is a pathway for mass transfer through the partial destruction of the oxide film caused by the surface of the aluminum powder or partial reduction by the chemical reaction, the oxygen concentration or moisture content in the atmosphere gas used is controlled to be low It is important to do.

In another aspect of the present invention, in the case of aluminum and its alloys, the sintering temperature should be lower than 660 DEG C, which is the melting point of pure aluminum, and in the case of most commercial aluminum alloys, the solidus temperature, at which the liquid phase begins to be formed, It is also important that the temperature at which degreasing is completed is overlapped with the temperature at which sintering is initiated so that the liquid aluminum is excessively generated in the state where the degreasing process is not completed, so that an unnecessary reaction with the organic binder decomposition product does not occur.

As described above, in order to produce a high-density sintered body, it is important to lower the oxygen content in the sintering gas atmosphere in the sintering step. For this purpose, it is also effective to use a dry atmosphere gas having a low oxygen content and charge the magnesium block as an oxygen scavenger in the furnace.

However, in the present invention, as a method of producing a high-density sintered body without using a separate sintering auxiliary agent or an oxygen scavenger, a method of manufacturing a sintered body using an organic binder in a molded body, Try the method.

According to the present invention, the degreasing and sintering process is performed under an argon gas atmosphere. Therefore, in the prior art using a nitrogen gas sintering atmosphere, it is not necessary to add a sintering aid element having a low melting point such as tin to prevent the formation of nitride which is generated on the surface of aluminum particles and hinders densification. However, if necessary, it may be added in an amount of 3% by weight or less. In this case, it is preferable that the degreasing-sintering is performed in an argon gas atmosphere according to the present invention.

Also, in the present invention, the degreasing process and the sintering process for removing the organic binder from the molded body made of aluminum composite powder mixed with aluminum or aluminum alloy powder and a reinforcing material are the same as those of aluminum and aluminum alloy. However, in the sintering process, undesirable compounds may be formed due to the reaction between aluminum and the reinforcing material. Therefore, it is necessary to appropriately adjust the composition on the alloy base according to each reinforcing material.

Hereinafter, the present invention will be described in more detail with reference to Fig.

1, a powder forming method of the present invention comprises a feedstock preparation step (S10) of preparing a feedstock by kneading a wax-based thermoplastic organic binder containing a polyolefin copolymer having aluminum powder or an aluminum alloy powder and a carbonyl group; A forming step (S20) of forming the feedstock; A degreasing step (S30) of removing the organic binder from the molded body; And a sintering step (S40) in which the degreased sintered body is densified by sintering under an argon gas atmosphere.

In particular, in order to increase sinterability of aluminum or aluminum alloy powder, it is preferable to select aluminum or aluminum alloy powder which is smaller than the size of powders used in conventional powder metallurgy and has a low oxygen content to ensure sinterability.

Therefore, the average particle size of the aluminum or aluminum alloy powder suitably used in the present invention is preferably 0.5 to 20 탆 or more, and more preferably 1 to 15 탆.

According to the present invention, the aluminum alloy powder may be an alloy powder produced by spraying in an alloyed solution state, or may be a mixture of pure aluminum and another alloy element powder or a master alloy powder such as Al-Mg for adding an alloy element Mixed powder.

In the present invention, the addition of an element having a low melting point such as tin as a sintering aid in the alloy component is not considered as an essential condition for high-density sintering.

 However, the sintering aid, especially tin or tin oxide (SnO), may be added in small amounts if necessary, and may be added in an amount of 0.1 to 3 wt% of tin and 0.3 to 5 wt% of tin oxide to 100 wt% of aluminum powder or aluminum alloy powder . However, although it may help to improve the sintering density, it may adversely affect the mechanical properties. Further, in the present invention, it is more preferable to carry out the addition in an argon gas atmosphere instead of a nitrogen gas atmosphere.

According to the present invention, as the organic binder used in the step (S10) of producing a feedstock, a wax is used as a base component and a backbone polymer component composed of a polyolefin, a polyolefin copolymer or a combination thereof, an organic substance serving as a surfactant or a lubricant And a degreasing finishing temperature of 490 to 540 DEG C, or a similar composition having a composition ratio known in the literature.

An example of the wax-based thermoplastic organic binder that can be effectively used in the present invention is an organic binder composition composed of paraffin wax, microcrystalline wax, polyolefin copolymer having a carbonyl group, polyolefin wax, .

In particular, the wax-based thermoplastic organic binder is preferably an organic binder composition containing 3 to 30% by weight of a polyolefin copolymer having a carbonyl group in total of 100% by weight.

The forming step S20 of the present invention can be carried out by a method selected from the group consisting of powder injection molding, compression molding and extrusion molding.

According to the present invention, the degreasing step (S30) for removing the organic binder from the formed body is preferably a heated degreasing using a neutral gas as a carrier gas.

However, a solvent extraction method using hexane or heptane, or a combination of supercritical fluid extraction degreasing using carbon dioxide and heating degreasing may also be used. In this case, partial degreasing is performed to remove low-melting point organic compound components such as wax and surfactant by solvent extraction or supercritical fluid extraction, and the remaining organic binder components such as the backbone polymer component are removed by heating and degreasing. .

As the carrier gas used in the heating degreasing process according to the present invention, argon gas is preferably used.

According to the present invention, the sintering process for densifying the degreasing body with a high-density sintered body having a relative density of 96% or more may be performed in an argon gas atmosphere, or after the inside of the sintering furnace is evacuated to 10 ^-3 torr or less, In a partial vacuum which is circulated through the sweep gas while being maintained at a reduced pressure of about 10 to 200 torr. However, in particular, in the case of an aluminum alloy degassing body, it is more preferable to use atmospheric-pressure argon gas as the sintering atmosphere gas.

The argon gas used in the degreasing step (S30) and the sintering step (S40) is preferably a dry gas having a low moisture content, preferably flowing at a flow rate of 0.1 to 20 L / min and a dew point temperature of -40 DEG C or less.

Particularly, in the present invention, when only the heating degreasing method is adopted in the degreasing step, the degreasing and sintering can be performed in a single heating step by setting one heating schedule. In this way, when degreasing and sintering are performed in the same furnace with a single heating schedule, a higher densification effect can be obtained and it is advantageous to obtain a high-density sintered body.

In the case of an industrially pure aluminum powder to which an alloy element is added in an amount of less than 0.5% by weight in aluminum in the present invention, it is preferable to perform sintering at a temperature within a range of 630 to 655 ° C.

In the present invention, in the case of aluminum alloy powder, it is preferable that the solidus temperature of the alloy is 480 DEG C or higher, preferably 520 DEG C or higher, and more preferably 540 DEG C or higher in order to obtain a high-density sound aluminum alloy sintered body.

The sintering temperature of the formed body made of an aluminum alloy powder having a total content of alloying elements added in an amount of 0.5 to 12% by weight based on 100% by weight of the total alloy is from 100% by volume % ≪ / RTI > to 30% by volume.

Further, in the present invention, the aluminum alloy may include Al-Cu-Mg- (Mn) series (AA2xxx series), Al-Mg series (AA5xxx series), Al-Mg- (AA6xxx series), Al-Zn-Mg- (Cu) series (AA7xxx series), 0.5 to 8% by weight of Mg with respect to 100% by weight of the total amount of aluminum alloy, Zn 0 to 8 wt%, Cu 0.1 to 3 wt%, Si 0 to 5 wt%, Ni 0 to 5 wt%, Fe 0 to 0.3 wt%, Mn 0 to 1 wt%, Zr 0 to 0.5 wt% 0.5 to 0.5% by weight, Ag 0 to 2% by weight, Sc 0 to 0.5% by weight, Li 0 to 2% by weight, and the balance aluminum.

Instead of using the aluminum alloy powder, an elemental powder such as magnesium, copper, silicon, zinc or the like or a master alloy powder containing these elements may be mixed with the pure aluminum powder.

The sintering in the present invention can be carried out in argon gas or vacuum, but it is more preferable to sinter in an argon gas atmosphere.

In the case of pure aluminum, the sintering is performed primarily in an argon gas gas atmosphere, and then the inside of the furnace is evacuated and sintering is continued for 1 hour or more, thereby further improving the density.

In the present invention, a nitride selected from the group consisting of SiC, B ₄ C, TiC and WC, Si ₃ N ₄ , AlN, TiN, c-BN and h-BN is added to the aluminum powder or aluminum alloy powder , Oxides selected from the group consisting of Al ₂ O ₃ , SiO ₂ , fly ash, Y ₂ O ₃ and ZrO ₂ , sulfides including MoS ₂ , borides including TiB ₂ , hard cobalt alloys such as T-800, Mo is selected from the group consisting of powders, short fibers or whiskers of refractory metals selected from the group consisting of polycarbonate, graphite, carbon nanotubes, graphene and diamond to provide a powder molding method using an aluminum matrix composite .

The average diameter of the reinforcing material is 0.05 to 40 占 퐉, and the reinforcing material is preferably contained in an amount of 1 to 30% by weight based on 100% by weight of the aluminum powder or the aluminum alloy powder.

According to the present invention, there is provided a sintered body part of aluminum powder, aluminum alloy powder or aluminum matrix composite manufactured by the powder molding method. The sintered part includes, but is not limited to, a precision shaped product selected from an impeller, turbine or linear motion bearing end cap.

Hereinafter, a method of producing a high-density and complicated shape product having a relative density of 96% or more by using aluminum or aluminum alloy powder by powder injection molding according to the present invention will be described in more detail with reference to the following examples. However, the present invention is not limited by these examples.

≪ Example 1 >

70% by weight of paraffin wax, 16% by weight of microcrystalline wax, and 10% by weight of an aluminum powder (MEP 105, manufactured by Eka Granules Co., Ltd.) having an average particle size of about 6 μm and a purity of 99.5% DP-730, manufactured by Hyundai EP Company, Korea) and 8 wt% of polyethylene wax and a pressure kneader at 140 캜 for 2 hours to prepare 300 g of feedstock having a solid phase ratio of 62%. The prepared feedstock was crushed to a size of about 6 mm and charged into an extruder having a mold clamping force of 80 tons, and a tensile test piece of an ASTM sub-size standard (US Material Test Specification ASTM E8) was prepared (Fig. 1A)

The manufactured injection mold was cut and visually inspected for the existence of defects therein. Further, it was confirmed through X-ray nondestructive inspection that a sound injection molding without defects was formed.

The tensile test specimen thus prepared was placed in an alumina boat, charged into a tubular furnace, and subjected to degreasing and heating in a single furnace in a single furnace while flowing argon gas (dew point temperature: -54 ° C) at a flow rate of 0.3 L / min.

The temperature was raised up to about 100 ° C for 1 hour and then kept for 1 hour. After heating to 280 ° C for 4 hours, the temperature was maintained for 3 hours. The temperature was again raised to 380 ° C for 4 hours, , Heated again to 520 DEG C over 2 hours, held for 30 minutes, then heated again for 1.5 hours, maintained at 650 DEG C for 2 hours, and then cooled. The tensile specimen sintered body thus produced had no apparent defects and exhibited a silvery white color. The sintered body exhibited a linear shrinkage of about 12.8% (Fig. 1-b). The density measured by Archimedes's principle showed a relative density of 96%. Formation of the Al ₄ C ₃ phase, a harmful compound, was not detected in the phase analysis by the X-ray diffraction experiment. The tensile strength at room temperature was 0.2% yield strength 71 MPa, tensile strength 132 MPa, and elongation 20%.

≪ Comparative Example 1 &

A confirmation test was conducted to compare the influence of gas species on sintering by changing the gas atmosphere to nitrogen gas using the tensile specimen injection body prepared in Example 1 as a specimen. The injection specimen was charged into a tube furnace, and degreasing and sintering were performed by the same heating schedule as in Example 1. Degreasing and sintering were performed while flowing nitrogen gas of 99.99% purity at a flow rate of 0.3 L / min instead of only argon gas. The sintered specimens produced were apparently dark brown with little sintering shrinkage and brittleness. And a relative sintered density of about 63%. As a result of phase analysis by X-ray diffraction analysis, AlN was produced in an amount of about 20% by weight.

≪ Example 2 >

60% by weight of paraffin wax and 26% by weight of microcrystalline wax were mixed with a gas spray aluminum powder having an average particle size of about 6 占 퐉 and a purity of 99.8% (British Aluminum Powder Company), maleic anhydride grafted polyethylene as a polyethylene copolymer having a carbonyl group 8 weight% of polyethylene wax and 6 weight% of polyethylene wax) was added to the mixture and kneaded at 135 占 폚 for 2 hours using a twin-cam mixer (Hoki Co., Ltd., Leocode 90) About 65 g of feedstock was prepared.

The prepared feedstock was crushed to a size of about 3 mm using a steel mortar and charged into a mold preheated to 120 ° C. and molded at a pressure of about 20 MPa. The length of the feedstock was 50 mm, the length of the parallel portion was 20 mm, A compact tensile test piece of arbitrary size having a parallel portion width of 5 mm was compression molded.

The thus prepared tensile test piece injection body was placed in an alumina boat and charged into a tubular furnace. The furnace was sintered at a flow rate of 0.3 L / min in an argon gas (dew point temperature: 54 ° C) At 650 캜 and a sintering time of 2 hours, so that the degreasing-sintering was performed successively in the same furnace. The tensile test specimen sintered in this manner exhibited a bright silver color and exhibited a shrinkage of about 12.8%. As a result of the density measurement by Archimedes' principle, the relative density was 97.8%. Phase analysis by X-ray diffraction showed no formation of Al ₄ C ₃ phase.

≪ Example 3 >

58 wt% of paraffin wax was added to an AA6061 aluminum alloy powder (British Aluminum Powder Company, composition Al-0.91 wt% Mg-0.70 wt% Si-0.26 wt% Cu) manufactured by gas spray having an average particle size of about 6 μm, 500 g of an organic binder consisting of 26% by weight of linseed wax, 10% by weight of maleic anhydride graft polyethylene (Korean Hyundai EP, DP-730) and 6% by weight of polyolefin wax as a polyethylene copolymer having a carbonyl group was added thereto, Kneaded in a double kneader and kneaded at 140 ° C for 2 hours to prepare a feedstock having a solid phase ratio of 67%. The thus prepared feedstock was crushed into a granular form, charged into a hopper of an injection machine, and then subjected to an injection operation to produce a sound tensile test piece injection body free from any defects therein. A disc-shaped specimen having a diameter of 20 mm and a height of 4 mm was also prepared by warm compression molding using a mold preheated to 118 ° C.

The prepared test specimens were placed in an alumina tray, charged into a tube furnace, degreased and sintered in a single heating schedule, and flowed at a flow rate of 0.3 L / min of argon gas (dew point of -53 ° C.). First, the temperature was raised to about 100 ° C over 1 hour, then maintained at that temperature for 1 hour, heated again to 280 ° C for 2 hours, maintained for 3 hours, again heated to 380 ° C for 4 hours, After holding for a further 2 hours, it was heated to 520 ° C for 2 hours, maintained at that temperature for 30 minutes, and then heated to a sintering temperature at a temperature rising rate of about 1.5 ° C per minute. At this time, the degreasing-sintering experiment was repeated while varying the sintering temperature from 580 to 630 ° C and the sintering time from 0 to 4 hours to determine the conditions under which the optimum sintering occurred.

2 is a photograph of sintered bodies (a), (b) sintered body at 580 ° C. for 0 hours, (c) sintered body at 590 ° C. for 0 hours, and (d) at 610 ° C. for 2 hours. As a result of the x-ray diffraction test on the sintered body, generation of Al ₄ C ₃ carbide was not observed. The densities of the sintered bodies were measured by density measurement using Archimedes' principle and converted to relative densities. The sintering density was changed from 94% at 580 ℃ to 600 ~ 630 ℃. The relative density of sintering was about 98% with almost no change in sintering temperature. Under this condition, linear shrinkage was about 12%. From this result, it can be seen that the optimum sintering temperature is about 600 to 630 캜.

FIG. 3 (curve 1) shows the result of examining the density change with the sintering time at 610 ° C. When the sintering temperature is reached, the relative density of sintering reaches 94% and the relative density reaches 98% after sintering for 1 hour. Fig. 4 shows the results of microstructural investigation of the specimen sintered at 610 캜 under an optical microscope. The microstructures appeared to be very homogeneous and healthy tissues without large pores. The test specimens sintered at 610 ℃ for 3 hours were subjected to solution treatment at 540 ℃ for 1 hour, water-cooled and then subjected to artificial aging (T6) at 170 ℃ for 8 hours. Figure 5 shows the tensile curves obtained. As a result of the tensile test, 0.2% yield strength of 302 MPa, tensile strength of 336 MPa, elongation of 6.3%, and elongation of 0.2% yield stress of 91 MPa, tensile strength of 221 MPa, elongation of 20.7% and T6 age hardened sintered specimen, % ≪ / RTI > FIG. 6 is a scanning electron microscope image of the fracture surface after the tensile test, showing a dimple structure typically observed at the fracture surface of the soft material.

≪ Comparative Example 2 &

The molded body prepared in Example 3 was repeatedly tested with only the kind of atmosphere gas for degreasing and sintering. That is, the gas used was a nitrogen gas having a purity of 99.99% and flowed at a flow rate of 0.4 L / min during the degreasing-sintering process.

The prepared tensile specimen sintered body was porous with a relative density of about 62% and exhibited brittleness, making it difficult to perform a tensile test. As a result of phase analysis by X-ray diffraction, about 18 wt% of aluminum nitride was formed in this specimen.

<Example 4>

This experiment was carried out repeatedly in the same manner as in Example 3 except that the kind of metal powder used was changed. That is, pure aluminum powder (Mefura MEP 105, manufactured by Eka Granules Co., Ltd.) having an average particle size of about 5 μm manufactured by air spraying, magnesium powder having a purity of -325 mesh having a purity of 99.8% (manufactured by Korea Hanamt Co., Ltd.) (CU-101, manufactured by Atlantic Instruments Engineering Co., USA) having a purity of 99.%, a silicon powder with a purity of 99.9% of a size of 10 m (SI-102, manufactured by American Electric Engineering Co., (Al-1 wt% Mg-0.5 wt% Si-0.25 wt% Cu) having a composition similar to that of AA6061 alloy (Alumix ^® , registered trademark of Ekag Gran Co., Germany) Were charged into a ball mill and mixed for about 2 hours.

The ASTM sub-size tensile test specimen injection body manufactured by the same method as in Example 3 and the test piece produced by compression molding were degassed by a single heating schedule while flowing argon gas at a flow rate of 0.3 L / min as in Example 3 And the sintering temperature was set to 610 캜 and the sintering time was changed from 0 to 4 hours.

Curve 2 in FIG. 3 shows the density change obtained according to the sintering time according to the present experiment. In the case of the present example using mixed powder of elemental metal powder, a maximum relative density of about 96.2% was obtained when sintering for 3 hours.

&Lt; Example 5 >

1% by weight of tin (SN-101, USA) having a particle size of 1 to 5 탆 and a purity of 99.9% was used in the same manner as in Example 2 except that AA6061 aluminum alloy powder having an average particle size of about 6 탆 (British Aluminum Powder Company) 500 g of feedstock was prepared by mixing the same with the same organic binder as used in Example 2 at a solid phase ratio of 67%. The prepared feedstock was granulated and injection molded to form an ASTM sub-size tensile test specimen, and a disc-shaped specimen with a diameter of 20 mm and a height of 4 mm was formed by hot compression molding.

The fabricated specimens were placed in an alumina tray and charged into a tube furnace. The furnace was degreased and sintered in a single heating schedule while flowing argon gas (dew point: -53 ° C) at a flow rate of 0.4 L / min. At this time, the experiment was repeated while varying the sintering temperature from 580 to 630 ° C and the sintering time from 0 to 4 hours in order to find the optimal sintering condition.

The relative density of the sintered specimens was calculated by density measurement using Archimedes' principle. As a result of sintering temperature change according to the sintering time of 3 hours, it was 94% at 580 ℃, and the relative density of sintering hardly changed at 600 ~ 630 ℃. The specimens under these conditions were subjected to a tensile test. As a result of the tensile test at room temperature under the sintering condition, the tensile strength was 215 MPa and the elongation was 15.2%. The tensile test specimens were annealed at 540 ℃ for 8 hours and then subjected to artificial aging (T6) heat treatment at 170 ℃ for tensile strength of 278 MPa and elongation of about 2.5% .

&Lt; Comparative Example 3 &

AA 6061 aluminum alloy powder (British Aluminum Company) having an average particle size of about 6 μm was used as in Example 3, and 1 wt% of tin having a particle size of 1 to 5 μm and a purity of 99.9% (SN-101, USA A stirrer was used to prepare a feedstock having a solid phase ratio of 67% and a tensile test piece injection body was produced.

The prepared test piece was placed in an alumina tray, charged into a tube furnace, and subjected to degreasing and sintering by heating in a single heating schedule of Example 4. The sintering temperature and the sintering time were set at 610 ° C. and the sintering time was 3 hours as in Example 3, and a purity of 99.99% nitrogen gas was passed at a flow rate of 0.4 L / min.

The density of the sintered body of the tensile test piece was measured by density measurement method using the principle of Archimedes, and as a result, the sintered density was about 96% of the theoretical density. As a result of the room temperature tensile test under the sintering condition, the tensile strength was 214 MPa and the elongation was 12%. Mechanical properties of tensile strength of 271 MPa and elongation of about 0.5% were obtained after tensile specimen sintered at 540 ℃ and thermally treated at 170 ℃ for 8 hours.

&Lt; Example 6 >

1 wt% (-) of tin oxide (SnO) having a particle size of -500 mesh and a purity of 99.9% was used as an AA6061 aluminum alloy powder (British Aluminum Powder Company) having an average particle size of about 6 μm as in Example 3, 325 mesh SO-601 powder, -500 mesh powder, classified by American Atlantic Engineering Co., Ltd.) was used, and the solid phase ratio was set to 67%, and the same organic binder and magnetic material as used in Example 2 And kneaded at 140 DEG C for 2 hours using a rotary double kneader to prepare 500 g of feedstock. The prepared feedstock was granulated and injection molding was carried out using an injection molding machine having a mold clamping force of 80 tons to prepare a tensile test piece.

The prepared specimens were placed in an alumina tray, and degreased and sintered in a tube furnace were subjected to a single heating schedule. The sintering temperature was set to 610 ° C. and the sintering time was set to 3 hours as in Example 2, and the argon gas (dew point -53 ° C.) Deg.] C / min.

The tensile test specimen sintered density was 97.9% of theoretical density by density measurement using Archimedes' principle. As a result of the room temperature tensile test under the sintering condition, the tensile strength was 204 MPa and the elongation was 17.4%. The tensile strength of the sintered specimen was 256 MPa and the elongation was 2.3% as a result of solution treatment at 540 ℃ and annealing at 170 ℃ for 8 hours of artificial aging (T6).

&Lt; Comparative Example 4 &

The degreasing-sintering experiment using the same heating schedule as in Example 5 was carried out on the tensile test piece injection body to which the 1 wt% SnO added in Example 5 was added, but a high purity nitrogen gas having a purity of 99.99% was used as the atmosphere gas And flowed at a flow rate of 0.4 L / min.

The tensile test specimen sintered density was 97.9% of theoretical density by density measurement using Archimedes' principle. As a result of the room temperature tensile test under the sintering condition, the tensile strength was 235 MPa and the elongation was 8.5%. The tensile strength of the sintered specimen was 255 MPa and the elongation was 0.4% as a result of solution treatment at 540 ° C and artificially aged (T6) heat treatment at 170 ° C for 8 hours.

&Lt; Example 7 >

(Mefura MEP 105, manufactured by Eka Granules Co.) having an average particle size of 5 μm and magnesium powder having a purity of -325 mesh and having a purity of 99.8% (manufactured by Korea Aerospace Exploration Co., Ltd. (CU-101, manufactured by American Atlantic Engineering Engineering Co., Ltd.) having a particle size of 1 to 5 μm, a purity of 99.9% and a silicon powder (SI-102, 1 wt.% Mg-0.5 wt.% Si-0.25 wt.% Cu mixed powder consisting of 1 wt.% Tin powder having a purity of 99.9% (SN-101, manufactured by American Electric Engineering Co., ) And 5% by weight of silicon carbide were ball milled for about 2 hours and mixed. Using an organic binder having the same composition as that used in Example 1, 500 g was weighed so as to have a solid phase ratio of 65% and put in a self-rotating double- The mixture was kneaded at 140 ° C for 2 hours, DeStack was prepared. The thus-prepared feedstock was crushed into granules, charged into an injection machine, and an impeller injection body was manufactured using an injection machine having a mold clamping force of 80 tons (FIG. 7-a).

The injection molded body thus prepared was charged into a box furnace having a retort of Inconel material and subjected to heating degreasing and sintering in a single process under an argon gas atmosphere. The argon gas used was dry with a dew point of -53 ° C. The temperature was raised to about 100 ° C for 1 hour at a flow rate of 0.5 L / min. Then, the temperature was maintained at that temperature for 1 hour. After heating, it was held at that temperature for 4 hours, then heated again to 380 ° C for 4 hours, held at that temperature for 4 hours, then heated again to 520 ° C over 2 hours, maintained at that temperature for 30 minutes The temperature was raised for 1.5 hours, maintained at 605 DEG C for 3 hours, and then cooled.

The tensile specimen sintered body thus produced was silver-white. The impeller sintered body thus produced is shown in Fig. 7-b in comparison with the injection molded body.

&Lt; Example 8 >

The composite powder obtained by mixing 99.5% of purity and 5% by weight of silicon carbide (SI 101, manufactured by American Electric Equipment Co., Ltd.) having an average particle size of 1 μm in an AA6061 alloy powder having an average particle size of 6 μm and the organic binder composition used in Example 3 To prepare a feedstock having a solid phase ratio of 67%. A small turbine injection body was fabricated using this feedstock and an injection machine having a mold clamping force of 80 tons. The injection molded body was charged into a box furnace having a retort of Inconel material inserted therein, and degreasing and sintering were carried out in one heating schedule as in Example 7. The sintering temperature was set to 610 ° C and the sintering time was set to 3 hours. Gas was flowed at a flow rate of 0.3 L / min by one heating schedule. Fig. 8 shows the appearance of the turbine sintered body thus produced.

&Lt; Example 9 >

An end cap, which is a component of a miniature linear motion bearing, was manufactured by using an AA6061 aluminum alloy powder feedstock having a solid phase ratio of 67% prepared in Example 3. The degreasing and sintering were carried out in a tube furnace under the same heating schedule as in Example 3, and sintering was carried out under an argon gas atmosphere at a sintering temperature of 610 DEG C and a sintering time of 2 hours. Fig. 9-a is an injection-molded body of the end cap thus manufactured, and Fig. 9-b shows an appearance of the sintered body. Injection bodies and sintered bodies are temporarily provided with dummy bars below the "C" shaped parts (FIG. 9-c) in order to prevent deformation of the formed bodies which may occur during degreasing and sintering . This is removed by cutting after sintering.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. And various modifications and variations are possible within the scope of the appended claims.

Claims (23)

A feedstock preparation step of preparing a feedstock by kneading a wax-based thermoplastic organic binder containing an aluminum powder or a polyolefin copolymer having an aluminum alloy powder and a carbonyl group;
A shaping step of shaping the feedstock;
A degreasing step of removing the organic binder from the molded body; And
And a sintering step of sintering the degreased sintered body in an atmosphere of argon gas to obtain densification. The powder molding method according to claim 1, wherein the wax-based thermoplastic organic binder comprises 3 to 30% by weight of a polyolefin copolymer having a carbonyl group in a total amount of 100% by weight. The powder molding method according to claim 1 or 2, wherein the polyolefin copolymer having a carbonyl group is maleic anhydride grafted polyethylene. The powder molding method according to claim 1, wherein the aluminum powder or the aluminum alloy powder has an average diameter of 1 to 20 m. The method of claim 1, wherein the aluminum alloy is selected from the group consisting of Al-Cu-Mg- (Mn) (AA2xxx) series, Al-Mg (AA5xxx series), Al-Mg-Si-Cu (AA6xxx) series having a magnesium content of 0.5 wt% Wherein the composition is one of a commercial aluminum alloy composition selected from the group consisting of Al-Zn-Mg- (Cu) (AA7xxx) series or an improved composition of a part thereof, 0.5 to 8 wt% 0 to 8% by weight of Zn, 0 to 3% by weight of Cu, 0 to 5% by weight of Si, 0 to 5% by weight of Fe, 0 to 0.3% by weight of Fe, 0 to 1% by weight of Mn, 0 to 0.5% 0 to 0.5 wt%, Ag 0 to 2 wt%, Sc 0 to 0.5 wt%, Li 0 to 2 wt%, and the balance aluminum. The aluminum alloy powder according to claim 1, wherein the aluminum alloy powder is an alloy powder prepared by spraying in an alloyed solution state, or a mixed powder obtained by mixing pure aluminum and another alloy element powder or a master alloy powder for the addition of another alloy element By weight. The powder molding method according to claim 1, further comprising 0.1 to 3% by weight of tin based on 100% by weight of the aluminum powder or aluminum alloy powder. The powder molding method according to claim 1, further comprising 0.3 to 5% by weight of tin oxide (SnO) based on 100% by weight of the aluminum powder or aluminum alloy powder. The method according to claim 1, wherein the forming step is performed by a method selected from the group consisting of powder injection molding, warm compression molding, and warm extrusion molding. The method according to claim 1, wherein the degreasing step is performed while flowing argon gas at a flow rate of 0.1 to 20 L / min. The method according to claim 1, wherein the degreasing step is performed by solvent extraction or partial degreasing by supercritical fluid extraction and heating degreasing in an argon gas atmosphere. The method of claim 1, wherein the sintering step is performed while flowing argon gas at a flow rate of 0.1 to 20 L / min. The powder molding method according to any one of claims 10 to 12, wherein the dew point of the argon gas is -40 캜 or less. The method of claim 1, wherein the degreasing step and the sintering step are performed in a single step in an argon gas atmosphere in the same furnace to remove and sinter the organic binder contained in the formed body. The powder molding method according to claim 1, wherein the sintering temperature of the molded body made from the aluminum powder is 630 to 655 ° C. The powder molding method according to claim 1, wherein the sintering temperature of the molded body made from the aluminum alloy powder is 540 to 640 ° C. The sintering temperature of the aluminum alloy powder according to claim 1, wherein the sintering temperature of the aluminum alloy powder is from 0.5 to 12% by weight based on 100% by weight of the alloy, Wherein the powder is present in a temperature range of 30% by volume with respect to 100% by volume of the total volume of the alloy. The method of claim 1, wherein the aluminum powder or the aluminum alloy powder is selected from the group consisting of carbides selected from the group consisting of SiC, B ₄ C, TiC and WC, Si ₃ N ₄ , AlN, TiN, c-BN and h- Oxides selected from the group consisting of Al ₂ O ₃ , SiO ₂ , Y ₂ O ₃ , fly ash and ZrO ₂ , sulfides including MoS ₂ , borides including TiB ₂ , hard compounds including T-800, Further comprising one or more reinforcing materials selected from the group consisting of powders and short fibers of the heat resistant metal selected from Mo, whiskers, polycarbon, graphite, carbon nanotubes, graphene and diamond. The powder forming method according to claim 18, wherein the average diameter of the reinforcing material is 0.05 to 40 탆. The powder forming method according to claim 18, wherein the reinforcing material is contained in an amount of 0.1 to 30% by weight based on 100% by weight of aluminum powder or aluminum alloy powder. A sintered body part made of an aluminum powder, an aluminum alloy powder or an aluminum matrix composite produced by the powder molding method according to claim 1 or 18. 22. The sintered parts part according to claim 21, wherein the sintered body part is an impeller or a small turbine. 22. The sintered component according to claim 21, wherein the sintered part is a linear motion bearing end cap.

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