阅读说明：本技术 高熵合金/金属玻璃复合材料及其制备方法 (High-entropy alloy/metal glass composite material and preparation method thereof ) 是由 余鹏 彭嘉欣 陈棋鑫 吴用 刘晓萍 陈澜生 谢晗晞 李冬梅 郭小龙 于 2020-07-08 设计创作，主要内容包括：本发明公开了一种高熵合金/金属玻璃复合材料,所述复合材料以金属玻璃为基体,在基体表面沉积高熵合金；该复合材料以金属玻璃作为基底,高熵合金作为外添加物,将高熵合金粉末外添加在金属玻璃基底上所制得的高熵合金/金属玻璃复合材料在维氏硬度上可达到699HV,具有硬度大、力学性能优良的特点。同时,在金属玻璃发生驰豫的过程中,由于高熵合金粉末的添加,使得复合材料中的晶体之间的位错减少,从而大大的降低了金属玻璃在高压下灾难性断裂的缺点。并且,本发明提供的高熵合金/金属玻璃复合材料在制作上简单、容易操作,在性能上有明显的提升。(The invention discloses a high-entropy alloy/metal glass composite material, which takes metal glass as a matrix, and high-entropy alloy is deposited on the surface of the matrix; the composite material takes the metal glass as a substrate, the high-entropy alloy as an external additive, and the Vickers hardness of the high-entropy alloy/metal glass composite material prepared by externally adding the high-entropy alloy powder on the metal glass substrate can reach 699HV, and the composite material has the characteristics of high hardness and excellent mechanical property. Meanwhile, in the process of relaxation of the metallic glass, due to the addition of the high-entropy alloy powder, dislocation among crystals in the composite material is reduced, and the defect of catastrophic fracture of the metallic glass under high pressure is greatly reduced. In addition, the high-entropy alloy/metal glass composite material provided by the invention is simple to manufacture and easy to operate, and the performance is obviously improved.)

1. A high-entropy alloy/metallic glass composite material is characterized in that: the composite material takes metallic glass as a substrate, and high-entropy alloy is deposited on the surface of the substrate.

2. A high entropy alloy/metallic glass composite material as claimed in claim 1, wherein: the high-entropy alloy has a chemical formula of TiAlFeCrCo_0.8Ni_2.1The chemical formula of the metallic glass is Zr₅₉Ni₂₁Al₂₀。

3. A high entropy alloy/metallic glass composite material as claimed in claim 2, wherein: the composite material has a chemical formula as follows: (Zr)₅₉Ni₂₁Al₂₀)_x(TiAlFeCrCo_0.8Ni_2.1)_yWherein x and y are natural numbers.

4. A high entropy alloy/metallic glass composite material as claimed in claim 3, wherein: x is 95 and y is 5.

5. A method of preparing a high entropy alloy/metallic glass composite material according to claim 1, characterized in that: the high-entropy alloy powder is adhered to the molten liquid of the metal glass and then rapidly cooled to form the high-entropy alloy/metal glass composite material.

6. A method of preparing a high entropy alloy/metallic glass composite material according to claim 5, characterized in that: molten liquid of the metallic glass is sucked into a copper mould filled with high-entropy alloy powder by adopting a suction casting method and then is rapidly cooled.

7. A method of preparing a high entropy alloy/metallic glass composite material according to claim 6, characterized in that: the method comprises the following steps:

a. placing the metal simple substance for forming the metal glass in an argon environment absorbed by sponge titanium to be smelted to prepare a master alloy ingot of the metal glass, wherein the smelting temperature is 2000-2050 ℃;

b. placing the metal simple substance for forming the high-entropy alloy in an argon environment absorbed by sponge titanium for smelting to prepare a master alloy ingot of the high-entropy alloy, and grinding the master alloy ingot into powder at 2000-2050 ℃;

c. and c, smelting the mother alloy ingot in the step a into molten liquid, sucking the molten liquid into a copper mold filled with high-entropy alloy powder through pressure difference, and then rapidly cooling.

8. A method of preparing a high entropy alloy/metallic glass composite material according to claim 7, wherein: in the steps a and b, the purity of the metal simple substance is not lower than 99.9%.

9. A method of producing a high entropy alloy/metallic glass composite material according to claim 8, characterized in that: in step c, the rapid cooling rate is 120K/s.

Technical Field

The invention relates to the field of composite materials, in particular to a high-entropy alloy/metal glass composite material and a preparation method thereof.

Background

The high-entropy alloy system is mainly composed of five or more metal elements, and the content of each component is 5-35%. The high-entropy alloy contains a large amount of metal elements and has large element disorder degree, and the high-entropy effect promotes the mixing among the elements, so that the multi-element high-entropy alloy forms a simple crystalline phase, namely, a Body Centered Cubic (BCC) phase and a Face Centered Cubic (FCC) phase or even an amorphous phase are formed by the mixed arrangement of a plurality of elements, and the formation of brittle intermetallic compounds is inhibited. Due to the fact that a plurality of elements cause entropy increase in an alloy system, the high-entropy alloy has four unique effects of a high-entropy effect, a lattice distortion effect, a diarrhea diffusion effect and a 'cocktail' effect on thermodynamics. Therefore, the high-entropy alloy has the characteristics of high hardness, corrosion resistance and the like, so that the high-entropy alloy is more and more concerned and researched by people. In recent years, metal glass has attracted much attention because of its high hardness, high strength and strong corrosion resistance. As a member of amorphous materials, unlike conventional crystalline materials, metallic glasses are structurally characterized by a disordered long-range order and a short-range ordered arrangement of atoms. However, since metallic glass has poor plasticity under high pressure, catastrophic fracture may occur. Therefore, the metallic glass is difficult to be applied to practical materials on a large scale.

Therefore, in order to solve the problems of poor plasticity and unobvious hardness of the metal glass under the condition of high pressure, a novel high-entropy alloy/metal glass composite material is needed, the hardness of the material is further improved on the basis of ensuring the hardness of the raw material, the plasticity of the material is obviously improved, and the mechanical property of the material is improved.

Disclosure of Invention

In view of the above, the present invention provides a high-entropy alloy/metallic glass composite material and a preparation method thereof, which further improve the hardness of the material, simultaneously significantly improve the plasticity of the material, and improve the mechanical properties of the material on the basis of ensuring the hardness of the raw material.

The high-entropy alloy/metal glass composite material takes metal glass as a matrix, and the high-entropy alloy is deposited on the surface of the matrix;

furthermore, the high-entropy alloy has a chemical formula of TiAlFeCrCo_0.8Ni_2.1The chemical formula of the metallic glass is Zr₅₉Ni₂₁Al₂₀；

Further, the composite material has a chemical formula of: (Zr)₅₉Ni₂₁Al₂₀)_x(TiAlFeCrCo_0.8Ni_2.1)_yWherein x and y are natural numbers.

Further, x and y are 95 and 5.

According to the preparation method of the high-entropy alloy/metal glass composite material, the high-entropy alloy powder is adhered to the molten liquid of the metal glass and then rapidly cooled to form the high-entropy alloy/metal glass composite material;

further, a suction casting method is adopted to suck the molten liquid of the metal glass into a copper mould filled with the high-entropy alloy powder and then the molten liquid is rapidly cooled;

further, the method comprises the following steps:

a. placing the metal simple substance for forming the metal glass in an argon environment absorbed by sponge titanium to be smelted to prepare a master alloy ingot of the metal glass, wherein the smelting temperature is 2000-2050 ℃;

b. placing the metal simple substance for forming the high-entropy alloy in an argon environment absorbed by sponge titanium for smelting to prepare a master alloy ingot of the high-entropy alloy, and grinding the master alloy ingot into powder at 2000-2050 ℃;

c. smelting the mother alloy ingot in the step a into molten liquid, sucking the molten liquid into a copper mold filled with high-entropy alloy powder through pressure difference, and then rapidly cooling;

furthermore, in the steps a and b, the purity of the metal simple substance is not lower than 99.9%;

further, in step c, the rapid cooling rate was 120K/s.

The invention has the beneficial effects that: the high-entropy alloy/metal glass composite material disclosed by the invention takes metal glass as a substrate, high-entropy alloy as an external additive, and high-entropy alloy powder is externally added on the metal glass substrate, so that the Vickers hardness of the high-entropy alloy/metal glass composite material can reach 699HV, and the high-entropy alloy/metal glass composite material has the characteristics of high hardness and excellent mechanical property. Meanwhile, in the process of relaxation of the metallic glass, due to the addition of the high-entropy alloy powder, dislocation among crystals in the composite material is reduced, and the defect of catastrophic fracture of the metallic glass under high pressure is greatly reduced. In addition, the high-entropy alloy/metal glass composite material provided by the invention is simple to manufacture and easy to operate, and the performance is obviously improved.

Drawings

The invention is further described below with reference to the following figures and examples:

FIG. 1 shows (Zr) obtained in example one₅₉Ni₂₁Al₂₀)₉₅(TiAlFeCrCo_0.8Ni_2.1)₅An X-ray diffraction pattern of the composite;

FIG. 2 shows (Zr) obtained in example one₅₉Ni₂₁Al₂₀)₉₅(TiAlFeCrCo_0.8Ni_2.1)₅Scanning electron microscope images of the fracture surface morphology of the composite material;

FIG. 3 shows (Zr) obtained in example one₅₉Ni₂₁Al₂₀)₉₅(TiAlFeCrCo_0.8Ni_2.1)₅Stress strain image of composite material and Zr₅₉Ni₂₁Al₂₀Is not in a state of being polymerizedGolden reference to the figure;

FIG. 4 shows (Zr) obtained in example four₅₉Ni₂₁Al₂₀)₉₅(TiAlFeCrCo_0.8Ni_2.1)₅A vickers hardness map of the composite;

FIG. 5 shows (Zr) obtained in example V₅₉Ni₂₁Al₂₀)₉₅(TiAlFeCrCo_0.8Ni_2.1)₅DTA curve chart of the composite material at the temperature rise rate of 20K/min;

FIG. 6 is a schematic diagram of a copper mold structure for preparing a composite material.

Detailed Description

According to the high-entropy alloy/metal glass composite material, metal glass is used as a matrix, and the high-entropy alloy is deposited on the surface of the matrix; due to the addition of the high-entropy alloy powder, the dislocation between crystals in the composite material is reduced. The composite material changes the structure among crystals in the original metal glass, so that the obtained material can effectively solve the problems that the metal glass has poor plasticity and is easy to fracture catastrophically under high pressure, and simultaneously can improve the hardness of the metal glass.

In this embodiment, the high entropy alloy has a chemical formula of TiAlFeCrCo_0.8Ni_2.1The chemical formula of the metallic glass is Zr₅₉Ni₂₁Al₂₀(ii) a The obtained material has more excellent mechanical properties.

In this embodiment, the chemical formula of the composition of the composite material is represented as: (Zr)₅₉Ni₂₁Al₂₀)_x(TiAlFeCrCo_0.8Ni_2.1)_yWherein x and y are 95 and 5; during the relaxation of the metallic glass, the dislocation between crystals in the composite material is reduced due to the addition of the high-entropy alloy powder. Thereby, the defect that the metallic glass is catastrophically broken under high pressure is greatly reduced. The content of the metal glass and the high-entropy alloy powder can be controlled, so that the composite material can neutralize the metal glass and the high-entropy alloy powder to the maximum extent, and the obtained composite material has high hardness and improves the plastic deformation of the material.

According to the preparation method of the high-entropy alloy/metal glass composite material, the high-entropy alloy powder is adhered to the molten liquid of the metal glass and then rapidly cooled to form the high-entropy alloy/metal glass composite material;

in the embodiment, a suction casting method is adopted to suck molten liquid of metal glass into a copper mould filled with high-entropy alloy powder and then the molten liquid is rapidly cooled; the copper mold used has the following structure: the copper mould for preparing the composite material comprises a copper mould body 9, a cooling cavity arranged in the copper mould body 9 and a powder discharge cavity 5 communicated with the cooling cavity and used for sucking the powder material into the cooling cavity (7, 8); the independent discharging cavity is arranged in the copper die body 9 and used for placing powder materials to be added in the preparation process, and the powder materials enter the cooling cavities (7, 8) in a suction mode, so that the powder materials fully enter the melted metal solution, and a uniform and compact metal glass substrate with stable performance and regular shape is obtained. The problems of uneven internal structure of the material, low cooling speed and the like caused by the traditional mode of attaching the powder material in the copper die body 9 can be solved.

The copper mould cooling cavities (7, 8) have different inner diameters; products with different sizes can be prepared by using the same mould according to requirements, so that the production efficiency is improved, the utilization rate of the mould is improved, and the aim of multiple purposes of one mould is fulfilled;

the powder discharge cavity 5 is communicated with the vent groove 4 of the copper mold body 9 to suck the powder material in the powder discharge cavity 5 into the cooling cavity (7, 8); the powder discharge cavity 5 is communicated with the furnace body through the vent groove 4 of the die body, and alloy liquid and metal powder are sucked into cooling cavities (7, 8) in a copper die body 9 by utilizing the pressure difference generated between the furnace cavity and a vacuum pump;

the powder feeding cavity 5 is a closed cavity and is communicated with cooling cavities (7, 8) through a feeding channel 6; the powder material in the powder discharge cavity 5 enters the cooling cavities (7, 8) through the feed channel 6 under the action of suction force and fully enters the flowing smelting solution, so that the mixing uniformity of the powder material and the smelting solution is enhanced;

the powder discharge cavities 5 are two and are axially and symmetrically distributed along the cooling cavities (7, 8); the mixing uniformity of the powder material and the smelting solution is improved, so that the required powder can be ensured to fully enter the metal solution, the required composite material has a uniform structure, and the metal solution can be ensured to be rapidly solidified;

the powder discharging cavity 5 is communicated with the vent groove 4 in a turning way; powder materials in the powder discharge cavity 5 are prevented from escaping from the vent groove 4; the cooling cavities (7, 8) with different inner diameters are communicated with each other by the same axle center; the melt forms a plurality of sections of products with different sizes on one flowing line, the structure is simple and easy to operate, the products with different sizes can be prepared by using the same mould according to the requirements, the production efficiency is improved, the utilization rate of the mould is improved, and the aim of multiple purposes of one mould is fulfilled;

the inner diameter of the cooling cavity (7, 8) is reduced along the flowing direction of the molten liquid, and the molten liquid flows from the large inner diameter section to the small inner diameter section of the cooling cavity (7, 8); the melt flows from the large inner diameter section 7 to the small inner diameter section 8 of the cooling cavity (7, 8), so that the proper flow rate of the melt is ensured, the cooling speed of the melt is not influenced, and the high-precision product is obtained.

The length of the large inner diameter section 7 of the cooling cavity (7, 8) is smaller than that of the small inner diameter section 8; the inner diameter of the large inner diameter section of the cooling cavity (7, 8) is twice that of the small inner diameter section. The flow rate and the cooling speed of the molten liquid are not influenced, and the molten liquid in the cooling cavities (7, 8) with different inner diameter sections is formed.

Copper mould body 9 includes that a plurality of sections are fan-shaped and can constitute the branch copper mould of cylinder, divide the copper mould both ends to have screw thread (3, 12), copper mould body 9 will through threaded sleeve (3, 12) divide the copper mould to fix for whole copper mould, open the upper end of copper mould body 9 have with the smelting cavity 1 of cooling die cavity (7, 8) intercommunication, smelt cavity 1 with it communicates with each other to have between cooling die cavity (7, 8) to inhale cast mouthful 2, blow vent 11 has been seted up to copper mould body 9 lower extreme, blow vent 11 with there is mounting groove 10, mountable bolt between the die cavity. The cooling cavities (7, 8) are sequentially distributed along the longitudinal axis of the copper die body (9). The lengths of the cooling cavities (7, 8) and the cooling cavities (7, 8) can be designed into different sizes according to specific requirements. The suction casting mouth 2 needs to be reserved at a position 1-2mm below the smelting cavity 1; the smelting cavity 1 is preferably a hemispherical crucible, and the diameter of the smelting cavity 1 is preferably 30 mm; the smelting cavity 1, the suction casting port 2, the cooling cavity (7, 8) and the vent 11 are coincided with the longitudinal axis of the copper mould body 9.

In this embodiment, the method includes the following steps:

a. placing the metal simple substance for forming the metal glass in an argon environment absorbed by sponge titanium to be smelted to prepare a master alloy ingot of the metal glass, wherein the smelting temperature is 2000-2050 ℃; placing high-purity metal simple substance in an argon environment absorbed by sponge titanium according to the atomic ratio, placing the simple substance from top to bottom according to the melting point, smelting and mixing for at least 6 times, controlling the smelting temperature to be 2000-2050 ℃, and smelting time for at least 15s each time to prepare Zr₅₉Ni₂₁Al₂₀Casting a mother alloy ingot;

b. placing the metal simple substance for forming the high-entropy alloy in an argon environment absorbed by sponge titanium for smelting to prepare a master alloy ingot of the high-entropy alloy, and grinding the master alloy ingot into powder at 2000-2050 ℃; smelting and mixing for at least 6 times, controlling the smelting temperature to be 2000-2050 ℃, and the smelting time of each time to be at least 15s to prepare TiAlFeCrCo_0.8Ni_2.1Casting a mother alloy ingot, and grinding the alloy ingot into powder; placing the powder in the copper mould with a charging cavity, screwing a screw on the bottom of the copper mould to prevent the powder from leaking out, and placing the copper mould in a non-consumable vacuum arc furnace.

c. Smelting the mother alloy ingot in the step a into molten liquid, sucking the molten liquid into a copper mold filled with high-entropy alloy powder through pressure difference, and then rapidly cooling; the molten liquid is quickly sucked into a copper mould filled with powder by utilizing the pressure difference between the inside and the outside of the cavity, so that the powder is bonded in a matrix, and then the high-entropy alloy/metal glass composite material with high strength and high plasticity can be prepared by quickly cooling.

In the embodiment, in the steps a and b, the purity of the metal simple substance is not lower than 99.9%; in step c, the rapid cooling rate is 120K/s.