KR20180035750A - In-situ strengthened high entropy powder, alloy thereof and method of manufacturing the same - Google Patents

Abstract

The present invention relates to a metal composite material for a multi-component high entropy alloy, and a manufacturing method thereof. More specifically, the present invention relates to the metal composite material for a multi-component high entropy alloy, and the manufacturing method, which comprise: a reinforcement material for producing an in-situ response; and the multi-component high entropy alloy. According to the present invention, a micro-reinforcing phase which is uniformly dispersed by the in-situ response can be formed. Therefore, provided is the metal composite material for a multi-component high entropy alloy which provides improved reinforcement effects.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a high entropy alloy powder, an alloy, and a method for manufacturing the same,

The present invention relates to an in-situ strengthened entropy alloy powder, an alloy (metal composite material) and a manufacturing method thereof.

High entropy alloys are metal alloys in which four or more elements constitute a single phase with nearly the same atomic fraction (equiatomic). Due to the entropy effect of these alloys, the multicomponent elements form a simple solid solution and exhibit excellent strength through solid solution strengthening. On the other hand, precipitates such as ceramics or intermetallic compounds are excellent in high temperature strength and excellent in hardness and abrasion resistance and have been widely used as reinforcing materials for metal alloy base.

Therefore, attempts have been made to improve mechanical properties through the introduction of reinforcing phases such as ceramics or metal halides into the entropy alloy base. A method for manufacturing such a high entropy alloy metal composite material can be produced by a casting method such as arc melting and powder metallurgy such as mixing and sintering method of reinforcing phase powder and entropy powder.

The casting method is advantageous in that it can produce metal composite materials at low cost. However, it has a disadvantage in that it is difficult to homogeneously disperse the strengthened phase due to the difference in density between the strengthened phase and the matrix. On the other hand, when the precipitation-strengthened entropy alloy metal composite material is produced by the powder metallurgy method, the homogeneous dispersion of the strengthening phase is easy, but when the reinforcing phase is manufactured from the outside, it is difficult to form a good interface between the strengthening phase and the base .

Therefore, a new manufacturing process with excellent mechanical properties at room temperature and high temperature is required because of the excellent interfacial properties between the base and the reinforcing phase in the production of the precipitated reinforced entropy alloy composite material.

Disclosure of the Invention The present invention has been made to solve the above-mentioned problems, and provides a multi-element high entropy powder, an alloy (metal composite material) and a method for manufacturing the same, which are formed by uniformly dispersing a finely reinforced phase in a high entropy alloy matrix, will be.

However, the problems to be solved by the present invention are not limited to the above-mentioned problems, and other problems not mentioned can be clearly understood by those skilled in the art from the following description.

According to one aspect of the present invention,

In situ Reaction Reinforcing Material; And polycrystalline high entropy alloys; To a multi-entangled, entropy alloy metal composite material.

According to an embodiment of the present invention, the reinforcing material may include the multi-component inter-component reaction precipitate; At least one of carbide, nitride, oxide, and boride of any one of the multi-component materials; Or both.

According to an embodiment of the present invention, the reinforcing material may be included in an amount of 0.01 to 50 wt% based on the alloy metal composite material.

According to one embodiment of the present invention, the reinforcement may have a particle size of 0.05 mu m to 50 mu m.

According to an embodiment of the present invention, the hardness of the multi-material high-entropy alloy metal composite material may be 800 (HV) or higher.

According to an embodiment of the present invention, the multi-element high entropy alloy is made of Fe, Ni, Al, Cu, Co, Mn, Zr, Hf, Re, W, Mo, Ti, V, Cr, And at least four or more elements selected from the group.

According to an embodiment of the present invention, the polycrystalline high entropy alloy may be one selected from the group consisting of quaternary alloys such as WMoCrNb, WVCrTa, MoVCrNb, VCrZrTa, or CrNbZrTa; WNbTiVMo, NbMoVTaW, WMoVCrTa, WVCrNbTa, WVNbZrTa, MoVCrZrTa or VCrNbZrTa; Or a hexagonal system alloy of WMoVCrZrTa, WMoCrNbZrTa, WVCrZrHfTa, MoVCrZrReHf or VCrNbZrHfTa; Lt; / RTI >

According to another aspect of the present invention,

Preparing a multi-component mixed powder for mixing an alloy constituent element and a reinforcement component; Forming a mechanical alloying powder that mechanically alloys the mixed powder; And high-temperature sintering the mechanical alloying powder; Wherein the high entropy alloy is formed by dispersing the reinforcement material by an in-situ reaction in the multi-entangled high entropy alloy in the high-temperature sintering step to form the multi-entangled high entropy alloy metal composite material ≪ / RTI >

According to an embodiment of the present invention, the step of forming the mechanical alloying powder is performed using a high energy ball milling apparatus, and the step of high-temperature sintering may be performed using a discharge plasma sintering apparatus.

According to one embodiment of the present invention, the step of forming the mechanical alloying powder and the step of high-temperature sintering may be carried out in a vacuum atmosphere; An inert gas atmosphere; Oxygen atmosphere; Or at least one of nitrogen, boron, and carbon; And the high-temperature sintering may be performed at a temperature of 100 ° C to 2500 ° C.

According to one embodiment of the present invention, the reinforcement component is an organic compound comprising at least one of oxygen, nitrogen, boron and carbon; Oxygen, nitrogen; boron; And carbon; And at least one selected from the group consisting of

INDUSTRIAL APPLICABILITY The present invention can provide a multi-material, high entropy alloy metal composite material having excellent interfacial properties between an alloy base and an in-situ reaction-producing reinforcement material and having improved mechanical properties at room temperature and high temperature.

In the present invention, a reinforcing material is formed by in situ sintering at high temperature sintering, so that a reinforcing material in a fine and uniformly dispersed state is formed in an alloy metal composite material as compared with conventional casting methods and powder metallurgy methods, The effect can be maximized.

FIG. 1 is a diagram illustrating a process flow diagram of a method of manufacturing a multi-material high entropy alloy metal composite material according to an embodiment of the present invention.
FIG. 2 shows an XRD pattern of a multi-material high entropy alloy metal composite material manufactured according to an embodiment of the present invention.
FIG. 3 is a scanning electron microscope (SEM) image of a multi-material high entropy alloy metal composite material manufactured according to an embodiment of the present invention.
FIG. 4 is a graph showing the hardness of the multi-element high entropy alloy metal composite material produced according to the present invention and the comparative example of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear. Also, terminologies used herein are terms used to properly represent preferred embodiments of the present invention, which may vary depending on the user, intent of the operator, or custom in the field to which the present invention belongs. Therefore, the definitions of these terms should be based on the contents throughout this specification. Like reference symbols in the drawings denote like elements.

The present invention relates to a multi-material high entropy alloy metal composite material, wherein the multi-material high entropy alloy metal composite material according to the embodiment of the present invention is characterized in that a fine in situ reaction- And excellent mechanical strength at low temperatures.

According to an embodiment of the present invention, the multi-material high entropy alloy metal composite material is a multi-material high entropy alloy; And an in situ reaction producing reinforcement; . ≪ / RTI >

As an example of the present invention, the multi-element high entropy alloy is an alloy base of a multi-element high entropy alloy metal composite material and includes Fe, Ni, Al, Cu, Co, Mn, Zr, Hf, Re, , At least four or more elements selected from the group consisting of V, Cr, Nb and Ta; . ≪ / RTI >

For example, the multi-element high entropy alloy may be any one of a quaternary alloy such as WMoCrNb, WVCrTa, MoVCrNb, VCrZrTa or CrNbZrTa; WNbTiVMo, WNbTaVMo, WMoVCrTa, WVCrNbTa, WVNbZrTa, MoVCrZrTa or VCrNbZrTa; Or a hexagonal system alloy of WMoVCrZrTa, WMoCrNbZrTa, WVCrZrHfTa, MoVCrZrReHf or VCrNbZrHfTa; And may preferably be WNbTaVMo and WNbTiVMo.

For example, each element constituting the multi-element high-entropy alloy may be included in the multi-element high-entropy alloy at a ratio of 5 to 35 atomic percent, and each element may be included at the same or different atomic percentages.

In one embodiment of the present invention, the in situ reaction-producing reinforcement material is a reinforcing phase (or a ceramic phase) precipitated by an in situ reaction in a high-temperature sintering process of a multi-material high entropy alloy metal composite material, So that it can be uniformly distributed in the alloy matrix with a fine particle size and a good interfacial state between the alloy matrix and the reinforcing phase is formed and the strengthening effect by the reinforcing phase can be improved.

For example, the in situ reaction-producing reinforcement may be a multi-component inter-component reaction precipitate in the alloy base; At least one of carbide, nitride, oxide, and boride of any one of the multi-component materials; Or both. For example, the oxide may be at least one selected from the group consisting of Al ₂ O ₃ , TiO ₂ , ZrO ₂ , Ta ₂ O ₅ , CrO ₂ , WO ₂ , W ₂ O ₃ and WO ₃ , carbide, TiC, ZrC, HfC, VC, NbC, TaC, Mo ₂ C, and from the group consisting of WC may be at least one selected, the nitride, TiN, ZrN, HfN, VN, NbN, TaN, AlN, And AlON. The boride may be at least one selected from the group consisting of TiB ₂ , ZrB ₂ , HfB ₂ , VB ₂ , NbB ₂ , TaB ₂ , WB ₂ and MoB ₂ . Or more.

For example, the in situ reaction-producing reinforcing material may be used in an amount of 0.01 to 50 wt% based on the alloy metal composite material; Preferably 0.01 to 10% by weight; More preferably from 0.03 to 0.5% by weight; When the content of the phosphorus-containing reinforcement material is within the above range, fine reinforcing phases can be formed well and the mechanical properties of the reinforcing phase can be improved.

For example, the in situ reaction-creating reinforcement may have a particle size of from 0.05 micrometers to 50 micrometers, and when the size of the reinforcement is within the above range, it provides excellent interfacial properties between the alloy matrix and the reinforcing phase, It is possible to reduce the difficulty of homogeneous dispersion of the reinforcing phase with increasing particle size.

As an example of the present invention, the hardness of the multi-material high entropy alloy metal composite material is 800 (HV) or higher; Or 800 (HV) to 1500 (HV).

The present invention relates to a method of manufacturing a multi-material high entropy alloy metal composite material, wherein the manufacturing method according to an embodiment of the present invention is a multi-material high entropy alloy metal composite material reinforced by a conventional powder metallurgy or casting method The present invention can provide a multi-material high entropy alloy metal composite material having enhanced strengthening effect.

1, a method of manufacturing a multi-element high entropy alloy metal composite according to an embodiment of the present invention will be described with reference to FIG. 1, (S1) of preparing a multi-component mixed powder in FIG. 1; FIG. Forming an alloyed powder (S2); And high-temperature sintering (S3); . ≪ / RTI >

In one embodiment of the present invention, step (S1) of preparing a multi-component mixed powder is a step of preparing a mixed powder for mixing an alloy constituent element and a reinforcement component. Step (S1) of preparing the mixed powder may utilize the powder mixing method used in the technical field of the present invention, and is not specifically mentioned in this specification. The alloy constituent element is an element constituting a multi-element high entropy alloy base, and is mentioned in the multi-element high entropy alloy metal composite material. The reinforcement component is a component capable of forming a reinforcing phase with an in situ reaction, for example, an organic compound containing at least one of oxygen, nitrogen, boron and carbon; Oxygen, nitrogen; boron; And carbon; And at least one selected from the group consisting of

In one embodiment of the present invention, the step (S2) of forming the alloying powder is a step of mechanically alloying the mixed powder to form a mechanical alloying powder.

For example, the step (S2) of forming the alloying powder may be carried out in an air atmosphere; Or at least one of nitrogen, boron, and carbon; Lt; / RTI >

For example, the step S2 of forming an alloyed powder may utilize a mechanical powder mixing apparatus, preferably a high energy ball milling apparatus, and may be used, for example, as a vibratory mill, Mill or the like may be used, and may be carried out at 500 to 800 rpm for 1 hour to 50 hours.

According to an embodiment of the present invention, the step (S3) of high-temperature sintering is a step of sintering the mechanical alloying powder to form a multi-material high entropy alloy metal composite material, wherein the multi- It is an alloy strengthened by the forming reinforcement. In the high-temperature sintering step (S3), the reinforcing phase may be formed by homogeneously dispersing the reinforcing phase by the in-situ reaction in the polycrystalline high entropy alloy, and the reinforcing phase may be formed by the reaction between the multi- And a fine particle phase precipitated by the reaction with the reinforcement component, and can provide an alloy base and good interface characteristics.

For example, the high-temperature sintering step (S3) may be a normal sintering method, a reaction sintering method, a pressure sintering method, an equal pressure sintering method, a gas pressure sintering method, an atmosphere pressure sintering method, a discharge plasma sintering method, A plasma sintering method can be used. The discharge plasma sintering method can improve the mechanical properties, that is, the hardness, and can lead to the miniaturization and homogeneous dispersion of the in situ reaction-producing reinforcement in the mechanical alloying powder, and the multi-source high entropy alloy metal composite material Can be provided.

For example, the high-temperature sintering step (S3) may suitably adjust the sintering atmosphere to form a strengthened phase with a uniform dispersion according to the reinforcement component,

Vacuum atmosphere; An inert gas atmosphere; Oxygen atmosphere; Or at least one of nitrogen, boron, and carbon; Lt; / RTI > In addition, step (S3) of high-temperature sintering may be performed at a temperature of 1250 캜 to 1800 캜 for 5 minutes to 1 hour.

While the invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. This is possible. Therefore, the scope of the present invention should not be limited by the described embodiments, but should be determined by the equivalents of the appended claims, as well as the appended claims.

[ Example  1a]

(Ball-to-blend powder = 10: 1 (mass ratio)) after mixing the alloy base element (W, Nb, Ta, Mo, V) and carbon powder at 0.4 wt.% At the same atomic ratio% And mechanically alloyed at 300 rpm for up to 40 hours to obtain a multi-core high entropy alloy powder.

[ Example  1b]

The multi-element high entropy alloy powder prepared in Example 1a was sintered at 1300 ° C (rate of temperature increase of 100 ° C / min) for 5 minutes by discharge plasma sintering. The SEM image, XRD and hardness of the manufactured alloy were measured and shown in Figs. 2 to 4. Fig.

[ Comparative Example  One]

The multialloyed high entropy alloy metal composite material was prepared by mechanical alloying and sintering in the same manner as in Example 1 except that 0.4 wt.% Of reinforced phase powder (TiC) was used. The hardness of the alloy thus prepared was measured and shown in Fig.

Referring to FIG. 2, the WNbTaVMo entropy alloy of Example 1b has a body centered cubic structure through mechanical alloying, and a metal carbide ceramic phase is formed by in-situ reaction after sintering . Also, referring to FIG. 3, a carbide ceramic phase can be identified by an in-situ reaction uniformly distributed in the alloy matrix of Example 1b.

4, the WNbTaVMo entropy alloy (Comparative Example 1) to which the metal carbide powder was added as a reinforcement material instead of the in-situ reaction (Comparative Example 1) contained WNbTaVMo entropy containing the metal carbide of Example 1b produced by the in- It can be confirmed that the hardness is lower than that of the alloy. This is because, when the reinforcing phase is precipitated by the in-situ reaction, the strengthened phase is uniformly distributed in the alloy base and the interfacial characteristics of the alloy base and the reinforcing phase are improved, Can be significantly improved.

The present invention can provide a multi-element high entropy alloy metal composite material with enhanced strengthening effect because a strengthened phase having fine and uniform dispersion is formed in the alloy matrix by in situ reaction at high temperature sintering.

Claims (9)

In situ Reaction Reinforcing Material; And polycrystalline high entropy alloys;
/ RTI >
The reinforcing material is contained in an amount of 0.01 wt% or more and less than 5 wt% with respect to the alloy metal composite material,
Wherein the polycrystalline high entropy alloy comprises at least one element selected from the group consisting of Zr, Hf, Re, W, Mo, V, Nb and Ta as a solid solution material.
The method according to claim 1,
The multi-entangled high entropy alloy includes at least four or more elements selected from the group consisting of Fe, Ni, Al, Cu, Co, Mn, Zr, Hf, Re, W, Mo, Ti, V, Cr, Wherein the composite material is a multi-element high entropy alloy metal composite material.
The method according to claim 1,
Wherein the reinforcement material is a precipitate formed by reaction between the reinforcement component and the multi-component component in the multi-element high entropy alloy; At least one of a carbide, a nitride, an oxide and a boride of any of a multi-component system by reaction between the reinforcement component and the multi-component system; Or both. ≪ / RTI >
The method according to claim 1,
Wherein the reinforcement material has a hardness of 850 (HV) or more of the multi-material high entropy alloy metal composite material.
The method according to claim 1,
Wherein the reinforcement has a particle size of from 0.05 占 퐉 to 0.10 占 퐉.
3. The method of claim 2,
The multi-entangled high entropy alloy is characterized in that,
WMoCrNb, WVCrTa, MoVCrNb, VCrZrTa or CrNbZrTa;
WNbTiVMo, NbMoVTaW, WMoVCrTa, WVCrNbTa, WVNbZrTa, MoVCrZrTa or VCrNbZrTa; or
WMoVCrZrTa, WMoCrNbZrTa, WVCrZrHfTa, MoVCrZrReHf or VCrNbZrHfTa; And the entropy alloy metal composite material.
Preparing a multi-component mixed powder for mixing an alloy constituent element and a reinforcement component;
Forming a mechanical alloying powder that mechanically alloys the mixed powder; And
High-temperature sintering the mechanical alloying powder;
Lt; / RTI >
In the high-temperature sintering step, the reinforcement material is formed and dispersed by the reinforcement component in the multi-entangled high entropy alloy and the in-situ reaction of the alloy base,
The reinforcing material is contained in an amount of 0.01 wt% or more and less than 5 wt% with respect to the alloy metal composite material,
Wherein the reinforcement component is an organic compound comprising at least one of oxygen, nitrogen, boron and carbon; Oxygen, nitrogen; boron; And carbon; Wherein the composite material comprises at least one selected from the group consisting of the following.
8. The method of claim 7,
The step of forming the mechanical alloying powder and the step of high-temperature sintering may include a vacuum atmosphere; An inert gas atmosphere; Oxygen atmosphere; Or at least one of nitrogen, boron, and carbon; Lt; / RTI >
Wherein the high-temperature sintering is performed at a temperature of 100 ° C to 2500 ° C.
8. The method of claim 7,
Forming a mechanical alloying powder that mechanically alloys the mixed powder; And wherein the reinforcement is not added during the high-temperature sintering step of the mechanical alloying powder.

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