WO2023231744A1

WO2023231744A1 - High-entropy alloy-based nano super-hard composite material reinforced by embedded particles, and preparation method therefor

Info

Publication number: WO2023231744A1
Application number: PCT/CN2023/093815
Authority: WO
Inventors: 戴建平; 陈正; 陈烜; 樊宇; 王叶青; 薛雨; 程春龙; 王林; 徐杰; 刘琨
Original assignee: 常熟天地煤机装备有限公司; 中国矿业大学
Priority date: 2022-05-31
Filing date: 2023-05-12
Publication date: 2023-12-07
Also published as: CN114807725A; CN114807725B

Abstract

The present application relates to the technical field of metal-based composite materials. Disclosed are a high-entropy alloy-based nano super-hard composite material reinforced by embedded particles, and a preparation method therefor. Reinforcing-phase particles and a high-entropy alloy matrix in the composite material have good wettability and have good interface bonding, such that the wear resistance of the composite material can be improved, and the shedding of reinforcing-phase particles during friction can be effectively avoided. The composite material comprises a high-entropy alloy matrix and reinforcing-phase particles, wherein the reinforcing-phase particles are dispersed in the high-entropy alloy matrix; the high-entropy alloy matrix comprises a basic matrix and a reinforcing matrix, the basic matrix comprising Al, Co, Cr, Fe, Ni and Mn, and the reinforcing matrix comprising Mo, Nb and Zr; and the reinforcing-phase particles comprise WC and TiC.

Description

Mosaic particle-reinforced high-entropy alloy-based nano-superhard composite material and preparation method thereof

Technical field

The present application relates to the technical field of metal matrix composite materials, and in particular to a high-entropy alloy-based nano-superhard composite material reinforced by inlaid particles and a preparation method thereof.

Background technique

Traditional composite materials usually use single or binary metals as the matrix and add reinforcement phases to improve their strength and hardness. However, the materials prepared in this way often have shortcomings such as single performance. For example, Fe-based composites have good corrosion resistance, but have limited hardness and wear resistance. In order to solve the above problems, high-entropy alloys with good comprehensive mechanical properties are used as matrix materials, and hard reinforcement phases are added to prepare composite materials, which greatly enhances the wear resistance of the materials. The research and development of high-entropy alloy-based composite materials meet the needs of more harsh working conditions. The superposition of various properties can improve the existing properties of the material or further obtain new characteristics.

High-entropy alloy-based composite materials have great potential as wear-resistant parts materials and high-temperature structural parts materials. They combine the excellent properties of the reinforcement phase and high-entropy alloy matrix and have very broad application prospects. However, the high-entropy alloy matrix composite materials in the related art have the disadvantages of poor wettability and poor interface bonding between the reinforcement phase and the high-entropy alloy matrix.

Contents of the invention

This application aims to solve at least one of the technical problems existing in the prior art. To this end, one purpose of this application is to propose a high-entropy alloy-based nano-superhard composite material reinforced by embedded particles. The reinforcing phase particles in the composite material have good wettability with the high-entropy alloy matrix and have a good interface. The combination can improve the wear resistance of composite materials and effectively prevent the reinforcement phase particles from falling off during friction.

Another purpose of this application is to propose a method for preparing a high-entropy alloy-based nano-superhard composite material reinforced by inlaid particles.

Another purpose of this application is to propose a high-entropy alloy-based nano-superhard composite material reinforced by inlaid particles, which is prepared by the above-mentioned preparation method.

In the first aspect, this application provides a mosaic particle-reinforced high-entropy alloy-based nano-superhard composite material, including: a high-entropy alloy matrix and reinforcing phase particles. The reinforcing phase particles are dispersed in the high-entropy alloy matrix. The high-entropy alloy matrix includes Basic matrix and reinforced matrix, the basic matrix includes Al, Co, Cr, Fe, Ni, Mn, the reinforced matrix includes Mo, Nb, Zr, and the reinforced phase particles include WC and TiC.

The embedded particle-reinforced high-entropy alloy-based nano-superhard composite material provided by this application has high hardness of WC and TiC. It can effectively improve the wear resistance of composite materials, and the atomic radius of the carbon element in the reinforced phase particles WC and TiC is small, which can form interstitial solid solution in the material, produce a solid solution strengthening effect, and improve the deformation resistance of the composite material. When the nano-scale powder refined by ball milling is sintered, the reinforcing phase particles WC and TiC in the material can not only play a load-bearing role, but also hinder dislocation movement, reduce the grain growth rate, and produce a nano-fine grain strengthening effect. The synergistic strengthening effect with the second phase greatly improves the wear resistance of composite materials. In addition, the reinforced phase particles WC and TiC in this application have good wettability with the Al, Co, Cr, Fe, Ni, Mn, Mo, Nb, and Zr metal elements in the high-entropy alloy matrix, ensuring high entropy The good combination of the alloy matrix and the reinforcing phase particles can effectively improve the reliability of the bonding between the reinforcing phase particles and the high-entropy alloy matrix, and avoid the phenomenon of aggravated material wear due to the falling off of the reinforcing phase particles during friction during use of the composite material. . In addition, in the friction and wear environment, when the composite material is used, the friction and heating will cause Al, Nb, Zr, and Cr elements to form a continuous and dense oxide layer on the surface of the composite material. In this way, the contact between the composite material and the composite material can be effectively reduced. The friction coefficient between objects can thereby reduce the wear of composite materials during use, extend the service life of composite materials, and reduce the cost of using composite materials.

In some embodiments of the present application, the mass fraction of the reinforcement phase particles is greater than or equal to 5% and less than or equal to 30%.

In some embodiments of the present application, the mass fractions of Al, Co, Cr, Fe, Ni, and Mn in the high-entropy alloy matrix are all greater than or equal to 10%.

In some embodiments of the present application, in the high-entropy alloy matrix, the mass fraction of the reinforced matrix is less than or equal to 5%. That is, the total mass fraction of Mo, Nb and Zr is less than or equal to 5%.

In a second aspect, this application provides a method for preparing a mosaic particle-reinforced high-entropy alloy-based nano-superhard composite material, including: weighing Al powder, Co powder, Cr powder, Fe powder, Ni powder, Mn powder, Mo Powder, Nb powder, Zr powder, WC powder, TiC powder, and mix them evenly to form composite material powder; ball mill the composite material powder to nanonize the composite material powder to obtain nanocrystalline powder; sintering the nanocrystalline powder, A bulk composite material was obtained.

The preparation method of this application uses Al, Co, Cr, Fe, Ni, Mn, Mo, Nb, Zr, WC, TiC and other powders as raw materials, and prepares them through powder metallurgy combined with discharge plasma sintering technology, so that the powder can be processed during the ball milling process. After medium crushing, refinement and uniform solid solution, it is installed into a graphite mold, placed in a furnace and consolidated into blocks at different sintering temperatures, and then a ball-disk reciprocating friction and wear testing machine is used to test its wear resistance. Composite materials using high-entropy alloys as a matrix have excellent comprehensive mechanical properties and can meet the wear-resistant requirements under harsher working conditions than traditional metal-based composite materials. In this preparation method, the addition of carbide-reinforced phase particles such as WC and TiC greatly improves the hardness and strength of the base material. The oxide layer formed by Al, Nb, Zr, and Cr elements during the friction and wear process has a "lubricating" effect. , which reduces the friction coefficient and wear amount, effectively improving the wear resistance of composite materials.

In some embodiments of the present application, Al powder, Co powder, Cr powder, Fe powder, Ni powder, Mn powder The purity of powder, Mo powder, Nb powder, Zr powder, WC powder and TiC powder is not less than 99.95%.

In some embodiments of the present application, the particle sizes of Al powder, Co powder, Cr powder, Fe powder, Ni powder, Mn powder, Mo powder, Nb powder, Zr powder, WC powder, and TiC powder are all greater than or equal to 30 μm and less than or equal to 50μm.

In some embodiments of the present application, ball milling the composite material powder to nanonize the composite material powder includes: sealing the composite material powder and dispersant into a ball mill jar for ball milling in an inert gas environment. During the ball milling process, The speed of the ball mill is 300r/min, and the ball milling time is 15h.

In some embodiments of the present application, during the ball milling process, the ball mill is paused for 20 to 30 minutes every 30 minutes of operation.

In some embodiments of the present application, sintering the nanocrystalline powder includes: using a discharge plasma sintering furnace to sintering the metal powder, heating the temperature in the discharge plasma sintering furnace to 1050°C ± 20°C, and the pressure Add to 40MPa, keep the temperature for 10 minutes and then cool to room temperature to prepare a block composite material.

In a third aspect, the present application provides a mosaic particle-reinforced high-entropy alloy-based nano-superhard composite material, which is prepared by the preparation method described in the second aspect.

Additional aspects and advantages of the application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the application.

Description of the drawings

The above and/or additional aspects and advantages of the present application will become apparent and readily understood from the description of the embodiments in conjunction with the following drawings, in which:

Figure 1 is a flow chart of a method for preparing a mosaic particle-reinforced high-entropy alloy-based nano-superhard composite material provided by some embodiments of the present application;

Figure 2 is a scanning electron microscope photo of the high-entropy alloy-based nano-superhard composite material reinforced with embedded particles provided by some embodiments of the present invention;

Figure 3 is a scanning electron microscope photograph of a mosaic particle-reinforced high-entropy alloy-based nano-superhard composite material provided by other embodiments of the present invention;

Figure 4 is a scanning electron microscope photograph of a high-entropy alloy-based nano-superhard composite material reinforced with inlaid particles provided in some embodiments of the present invention;

Figure 5 is a scanning electron microscope photograph of a high-entropy alloy-based nano-superhard composite material reinforced with embedded particles provided in some further embodiments of the present invention.

Detailed ways

The embodiments of the present application are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the drawings are exemplary and are only used to explain the present application and cannot be understood as limiting the present application.

The following describes a mosaic particle-reinforced high-entropy alloy-based nano-superhard composite material according to embodiments of the present application. The composite material includes: a high-entropy alloy matrix and reinforced phase particles, and the reinforced phase particles are dispersed in the high-entropy alloy matrix. Specifically, the reinforcement phase particles are evenly dispersed in the high-entropy alloy matrix.

Specifically, the high-entropy alloy matrix includes the metal elements Al (aluminum), Co (cobalt), Cr (chromium), Fe (iron), Ni (nickel), Mn (manganese), Mo (molybdenum), Nb (niobium), Zr (zirconium), reinforcing phase particles include WC (tungsten carbide), TiC (titanium carbide). Among them, the composite material can be a block.

In some embodiments, the composite material can be prepared by sintering. Specifically, during the processing, the composite material powder can be sintered to obtain a bulk composite material. During the sintering process, the Mo, Nb, and Zr elements that strengthen the matrix can reduce the surface tension between the molten metal and the reinforcement phase particles during the sintering process, make the reinforcement phase particles evenly distributed, and introduce a certain interface reaction to improve the performance of the composite material. strength.

In the composite materials of the embodiments of the present application, WC and TiC have high hardness, which can effectively improve the wear resistance of the composite materials, and the atomic radius of the carbon element in the reinforcing phase particles WC and TiC is small, which can form interstitial solid solutions in the material. , producing a solid solution strengthening effect and improving the deformation resistance of composite materials. When the nano-scale powder refined by ball milling is sintered, the reinforcing phase particles WC and TiC in the material can not only play a load-bearing role, but also hinder dislocation movement, reduce the grain growth rate, and produce a nano-fine grain strengthening effect. The synergistic strengthening effect with the second phase greatly improves the wear resistance of composite materials. At the same time, during the processing process, the reinforcing phase particles WC and TiC can not only play a load-bearing role, but also hinder dislocation movement, resulting in fine grain strengthening and second phase synergistic strengthening effects, which greatly improves the wear resistance of the composite material.

In addition, the reinforced phase particles WC and TiC in this application have good wettability with the Al, Co, Cr, Fe, Ni, Mn, Mo, Nb, and Zr metal elements in the high-entropy alloy matrix, ensuring high entropy The good combination of the alloy matrix and the reinforcing phase particles can effectively improve the reliability of the bonding between the reinforcing phase particles and the high-entropy alloy matrix, and avoid the phenomenon of aggravated material wear due to the falling off of the reinforcing phase particles during friction during use of the composite material. . .

In addition, by adding Al, Nb, Zr, and Cr elements to the high-entropy alloy matrix, during the use of the composite material, the Al, Nb, Zr, and Cr elements can form a continuous and dense oxide layer on the surface of the composite material through friction and heating. , In this way, the friction coefficient between the composite material and the contact object can be effectively reduced, thereby reducing the wear of the composite material during use, extending the service life of the composite material, and reducing the cost of using the composite material.

In some embodiments, the mass fraction of the reinforcement phase particles is greater than or equal to 5% and less than or equal to 30%. That is, the total mass fraction of WC and TiC is greater than or equal to 5% and less than or equal to 30%. Among them, the mass fraction of WC and the mass fraction of TiC can be equal.

For example, the mass fraction of WC can be 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5 %, 9%, 9.5%, 10%, 11.5%, 12%, 12.5%, 13%, 13.5%, 14%, 14.5%, 15%, etc. The mass fraction of TiC can be 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, 10%, 11.5%, 12%, 12.5%, 13% , 13.5%, 14%, 14.5%, 15%, etc.

Among them, when the mass fraction of the reinforced phase particles is greater than 30%, the reinforced phase particles are easily agglomerated in the high-entropy alloy matrix, making the distribution of the reinforced phase particles in the high-entropy alloy matrix uneven. When the mass fraction of reinforcing phase particles is less than 5%, the purpose of enhancing the wear resistance of the composite material cannot be achieved. Therefore, by controlling the mass fraction of the reinforcing phase particles to be greater than or equal to 5% and less than or equal to 30%, the wear resistance of the composite material can be enhanced while avoiding the agglomeration of the reinforcing phase particles in the high-entropy alloy matrix, making the reinforcement The phase particles are more evenly distributed in the high-entropy alloy matrix.

In some embodiments, the mass fraction of Mo, Nb, and Zr elements in the reinforced matrix is less than or equal to 5%. For example, the mass fraction of the reinforced matrix is 1%, 2%, 3%, 4% or 5%. Optionally, the mass fractions of Mo, Nb, and Zr elements are equal. In this way, during the sintering process, Mo, Nb, and Zr elements can be used to reduce the surface tension between the molten metal and the reinforcement phase particles during the sintering process, so that the reinforcement phase particles can be evenly distributed. The interface reaction between the reinforced phase particles and the matrix can ensure a good combination between the two. Less amounts of Mo, Nb, and Zr elements reduce the cost of composite materials.

For example, the mass fraction of Mo is 0.333%, 0.667%, 1%, 1.333% or 1.667%. The mass fraction of Nb is 0.333%, 0.667%, 1%, 1.333% or 1.667%. The mass fraction of Zr is 0.333%, 0.667%, 1%, 1.333% or 1.667%.

In some embodiments, the mass fractions of Al, Co, Cr, Fe, Ni, and Mn are all equal. For example, the mass fractions of Al, Co, Cr, Fe, Ni, and Mn are all greater than or equal to 10%.

The following describes a method for preparing a mosaic particle-reinforced high-entropy alloy-based nano-superhard composite material provided by an embodiment of the present application with reference to FIG. 1 .

Please refer to Figure 1. Figure 1 is a flow chart of a method for preparing a mosaic particle-reinforced high-entropy alloy-based nano-superhard composite material provided by some embodiments of the present application. The preparation method of embedded particle-reinforced high-entropy alloy-based nano-superhard composite materials includes:

Step S100: Weigh Al powder, Co powder, Cr powder, Fe powder, Ni powder, Mn powder, Mo powder, Nb powder, Zr powder, WC powder, and TiC powder, and mix them evenly to form composite material powder;

Specifically, the powder required for the above composite material is weighed according to a certain ratio and mixed evenly. For example, the mass fraction of the reinforcing phase particles is 5% to 30%, the total mass fraction of Mo powder, Nb powder, and Zr powder (that is, the mass of the reinforced matrix) is less than or equal to 5%, and the Al powder, Co powder, The mass fractions of Cr powder, Fe powder, Ni powder and Mn powder are all greater than or equal to 10%.

In some embodiments of the present application, the purity of Al powder, Co powder, Cr powder, Fe powder, Ni powder, Mn powder, Mo powder, Nb powder, Zr powder, WC powder, and TiC powder is not less than 99.95%.

In some embodiments of the present application, Al powder, Co powder, Cr powder, Fe powder, Ni powder, Mn powder The particle sizes of powder, Mo powder, Nb powder, Zr powder, WC powder, and TiC powder are all greater than or equal to 30 μm and less than or equal to 50 μm. For example, the particle size of Al powder, Co powder, Cr powder, Fe powder, Ni powder, Mn powder, Mo powder, Nb powder, Zr powder, WC powder, TiC powder can be 30 μm, 35 μm, 45 μm, 50 μm, etc.

Step S200: Perform ball milling on the composite material powder to nanonize the composite material powder to obtain nanocrystalline powder;

In some embodiments of the present application, the composite material powder is ball milled to nanonize the composite material powder, including: sealing the composite material powder and dispersant in a ball milling tank under an inert gas (such as argon) environment for ball milling. , During the ball milling process, the speed of the ball mill is 300r/min, and the ball milling time is 15h. In this way, the composite material powder can be nanosized, which is beneficial to improving the mixing uniformity of the reinforcement phase particles and the high-entropy alloy matrix.

Further, in some embodiments of the present application, during the ball milling process, the ball mill is paused for 20 to 30 minutes every 30 minutes of operation. In this way, the temperature inside the spherical tank can be prevented from being too high.

Step S300: Sintering the nanocrystal powder to obtain a bulk composite material.

In some embodiments of the present application, sintering the nanocrystalline powder includes: using a discharge plasma sintering furnace to sintering the metal powder. After placing the nanocrystalline powder into the discharge plasma sintering furnace, the discharge The temperature in the plasma sintering furnace is heated to 1050°C ± 20°C, the pressure is increased to 40MPa, and the temperature is maintained for 10 minutes and then cooled to room temperature to obtain a block composite material.

During the sintering process, the nano-scale powder refined by ball milling can be prepared by sintering to further ensure the strength, toughness and wear resistance of the material. In addition, since Mo, Nb, and Zr elements are added to the high-entropy alloy matrix, the surface tension between the molten metal and the reinforced phase particles during the sintering process can be reduced, the reinforced phase particles can be evenly distributed, and a certain interfacial reaction can be introduced to improve the composite The strength of the material.

The preparation method of the embedded particle-reinforced high-entropy alloy-based nano-superhard composite material in the embodiment of the present application has the following advantages:

(1) The components of the high-entropy alloy matrix in this application include Al, Co, Cr, Fe, Ni, Mn, Mo, Nb, and Zr elements. The selected elements all have good wettability with the reinforcement phase particles WC and TiC, so that This ensures that the high-entropy alloy matrix of the composite material can be well combined with the reinforcement phase particles to form a better interface bond. Moreover, during the sintering process, carbides decompose and combine with Fe and Cr elements to form carbides, which increases the hardness of the material and achieves the purpose of improving the wear resistance of the material.

(2) During the friction heating process of composite materials, Al, Nb, Zr, and Cr elements can form a continuous and dense oxide layer. The oxide layer formed by Al, Nb, Zr, and Cr elements during the friction and wear process has a "lubricating" effect, which reduces the friction coefficient and wear amount of the composite material, effectively improving the wear resistance of the composite material. At the same time, the presence of WC and TiC reinforced phase particles can increase the strength and hardness of the material, further improve the friction and wear properties of the composite material, and improve the wear resistance of the composite material.

(3) Use mechanical alloying methods to refine metal powders, and sinter nanoscale powders into solids through discharge plasma sintering technology. This process allows the sintered powder particles to generate plasma under the action of a pulse current of 5000 to 8000A, which can quickly achieve densification within 1 to 3 minutes. The resulting material has a fine and uniform structure, good strength and toughness, and effectively saves production time. Improve preparation efficiency.

(4) The addition of a small amount of Mo, Nb, and Zr elements reduces the surface tension between the molten metal and the reinforcing phase during the sintering process, makes the particles evenly distributed, and introduces a certain interface reaction to improve the strength of the composite material.

(5) This application obtains composite materials with different reinforcing phase particle contents by regulating the content of reinforcing phase particles, and then uses different sintering temperatures to prepare the materials, study and analyze their organizational structure, and finally obtain the optimal ratio and process through performance comparison.

Embodiments of the present application also provide a mosaic particle-reinforced high-entropy alloy-based nano-superhard composite material, which is prepared by the above preparation method.

The present application will be further described below in conjunction with specific embodiments.

Example 1

A high-entropy alloy-based nano-superhard composite material reinforced by embedded particles. The high-entropy alloy matrix components include Al, Co, Cr, Fe, Ni, Mn, Mo, Nb, and Zr elements, and the reinforcing phase particles include WC and TiC. The mass fraction of reinforcement phase particles is 5%, the total mass fraction of Mo, Nb, and Zr is less than or equal to 5%, and the mass fractions of Al, Co, Cr, Fe, Ni, and Mn elements are all greater than 10%.

In this embodiment, the preparation method of the embedded particle-reinforced high-entropy alloy-based nano-superhard composite material is:

(1) Weigh the metal powder required to prepare composite materials according to the determined ratio;

(2) Seal the metal powder and dispersant (alcohol) into a ball mill jar under an inert gas (argon) environment;

(3) Put the ball mill tank on the ball mill to refine the powder. Set the ball milling speed to 300r/min and the time to 15h. The ball mill will pause for 30min every 30min of operation. After the ball milling is completed, put the wet powder taken out into the vacuum drying box. Dry, set the temperature to 65°C and the time to 6 hours. Take it out after the drying is completed;

(4) Put the metal powder into the graphite mold and put it into a discharge plasma sintering furnace for sintering. The sintering temperature is set to 1050℃±20℃, the applied pressure is 40MPa, and the temperature is maintained for 10 minutes and then cooled to room temperature to obtain a block composite. Material.

Figure 2 is a scanning electron microscope photograph of the inlaid particle-reinforced high-entropy alloy-based nano-superhard composite material prepared in Example 1. It can be seen from Figure 2 that the white reinforcement phase particles in this embodiment are evenly distributed on the high-entropy alloy matrix.

Example 2

A high-entropy alloy-based nano-superhard composite material reinforced by embedded particles. The high-entropy alloy matrix components include Al, Co, Cr, Fe, Ni, Mn, Mo, Nb, and Zr elements, and the reinforcing phase particles include WC and TiC. The mass fraction of reinforcement phase particles is 10%, the total mass fraction of Mo, Nb, and Zr is less than or equal to 5%, and the total mass fraction of Al, Co, Cr, Fe, Ni, and Mn The mass fraction of elements is greater than 10%.

Figure 3 is a scanning electron microscope photograph of the mosaic particle-reinforced high-entropy alloy-based nano-superhard composite material prepared in Example 2. It can be seen from Figure 3 that the white reinforcement phase particles in this embodiment are evenly distributed on the high-entropy alloy matrix.

Example 3

A high-entropy alloy-based nano-superhard composite material reinforced by embedded particles. The high-entropy alloy matrix components include Al, Co, Cr, Fe, Ni, Mn, Mo, Nb, and Zr elements, and the reinforcing phase particles include WC and TiC. The mass fraction of reinforcement phase particles is 15%, the total mass fraction of Mo, Nb, and Zr is less than or equal to 5%, and the mass fractions of Al, Co, Cr, Fe, Ni, and Mn elements are all greater than 10%.

Figure 4 is a scanning electron microscope photograph of the inlaid particle-reinforced high-entropy alloy-based nano-superhard composite material prepared in Example 3. It can be seen from Figure 4 that the white reinforcement phase particles in this embodiment are evenly distributed on the high-entropy alloy matrix.

Example 4

A high-entropy alloy-based nano-superhard composite material reinforced by embedded particles. The high-entropy alloy matrix components include Al, Co, Cr, Fe, Ni, Mn, Mo, Nb, and Zr elements, and the reinforcing phase particles include WC and TiC. The mass fraction of reinforcement phase particles is 30%, the total mass fraction of Mo, Nb, and Zr is less than or equal to 5%, and the total mass fraction of Al, Co, Cr, Fe, Ni, and Mn The mass fraction of elements is greater than 10%.

Figure 5 is a scanning electron microscope photograph of the inlaid particle-reinforced high-entropy alloy-based nano-superhard composite material prepared in Example 4. It can be seen from Figure 5 that the white reinforcement phase particles in this embodiment are evenly distributed on the high-entropy alloy matrix.

In addition, Table 1 shows the mechanical property test results of the composite materials in Examples 1-4.

Table 1 Mechanical properties of composite materials in Examples 1-4

As can be seen from Table 1, the composite material in this application exhibits extremely excellent mechanical properties. Specifically, the hardness of the composite material in Example 1 is 996.3HV, the compressive strength is 1414.8MPa, the wear amount is 427299.36μm ³ , and the friction coefficient is 0.35. The hardness of the composite material in Example 2 is 1164.3HV, the compressive strength is 1565.4MPa, the wear amount is 442170.16μm ³ , and the friction coefficient is 0.32. The hardness of the composite material in Example 3 is 1531.7HV, the compressive strength is 1395.1MPa, the wear amount is 250740.32μm ³ , and the friction coefficient is 0.37. The hardness of the composite material in Example 4 is 1392.0HV, the compressive strength is 995.7MPa, the wear amount is 287661.44μm ³ , and the friction coefficient is 0.39.

In addition, it can be seen from Table 1 that the hardness and compressive strength of the composite material show a trend of first increasing and then decreasing as the mass fraction of WC and TiC increases, and the wear amount and friction coefficient show a trend of decreasing and then increasing. , the performance of the composite material is the best when adding 10 to 11wt% of reinforcing phase particles.

In addition, compared with a composite material that does not add reinforcing phase particles but only includes a high-entropy alloy matrix, the friction coefficient of the composite material in the embodiment of the present application is reduced by more than 74%, and the wear amount is reduced by more than 60%.

In the description of this specification, reference to the terms "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" or the like is intended to be incorporated into the description of the implementation. An example or example describes a specific feature, structure, material, or characteristic that is included in at least one embodiment or example of the present application. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Although the embodiments of the present application have been shown and described, those of ordinary skill in the art will understand that various changes, modifications, substitutions and modifications can be made to these embodiments without departing from the principles and purposes of the present application. The scope of the application is defined by the claims and their equivalents.

Claims

A mosaic particle-reinforced high-entropy alloy-based nano-superhard composite material, characterized by comprising: a high-entropy alloy matrix and reinforcing phase particles, the reinforcing phase particles are dispersed in the high-entropy alloy matrix, and the high-entropy alloy matrix is dispersed in the high-entropy alloy matrix. The alloy matrix includes a basic matrix and a reinforced matrix. The basic matrix includes Al, Co, Cr, Fe, Ni, and Mn. The reinforced matrix includes Mo, Nb, and Zr. The reinforcing phase particles include WC and TiC.
The composite material according to claim 1, wherein the mass fraction of the reinforcement phase particles is greater than or equal to 5% and less than or equal to 30%.
The composite material according to claim 1, characterized in that the mass fraction of the reinforcing phase particles is greater than or equal to 10% and less than or equal to 15%.
The composite material according to any one of claims 1 to 3, characterized in that the mass fraction of the reinforced matrix is less than or equal to 5%.
A method for preparing a mosaic particle-reinforced high-entropy alloy-based nano-superhard composite material according to any one of claims 1 to 4, characterized in that it includes:

Weigh Al powder, Co powder, Cr powder, Fe powder, Ni powder, Mn powder, Mo powder, Nb powder, Zr powder, the WC powder, and the TiC powder in proportion, and mix them evenly to form a composite powder;

Perform ball milling treatment on the composite material powder to nanonize the composite material powder to obtain nanocrystalline powder;

The nanocrystalline powder is sintered to obtain a bulk composite material.
The preparation method according to claim 5, characterized in that the Al powder, the Co powder, the Cr powder, the Fe powder, the Ni powder, the Mn powder, the Mo powder, the The particle sizes of the Nb powder, the Zr powder, the WC powder, and the TiC powder are all greater than or equal to 30 μm and less than or equal to 50 μm.
The preparation method according to claim 5, characterized in that the composite material powder is ball milled to nanometerize the composite material powder, including:

The composite material powder and dispersant were sealed into a ball milling tank under an inert gas environment for ball milling. During the ball milling process, the rotation speed of the ball mill was 300 r/min, and the ball milling time was 15 hours.
The preparation method according to claim 7, characterized in that during the ball milling process, the ball mill is paused for 20 to 30 minutes every 30 minutes of operation.
The preparation method according to any one of claims 6 to 8, characterized in that sintering the nanocrystalline powder includes: using a discharge plasma sintering furnace to sintering the metal powder, and The temperature in the solid sintering furnace is heated to 1050°C ± 20°C, the pressure is increased to 40MPa, and the temperature is maintained for 10 minutes and then cooled to room temperature to prepare a block composite material.
A mosaic particle-reinforced high-entropy alloy-based nano-superhard composite material, characterized in that it is made according to the claims It is prepared by the preparation method described in any one of 6-8.