High-entropy alloy reinforced stainless steel composite material and selective laser additive manufacturing method thereof

Abstract

The invention discloses a high-entropy alloy reinforced stainless steel composite material and a selective laser additive manufacturing method thereof, and belongs to the technical field of design and preparation of steel-based composite materials. According to the composite material, a hard body-centered cubic high-entropy alloy phase and a stainless steel matrix are combined, the composite material is formed through the selective laser additive manufacturing technology, a composite material particle reinforced phase is hard high-entropy alloy particles, the hard high-entropy alloy particles are obtained through surface treatment and are distributed in the stainless steel matrix in a dispersed mode, and the reinforced phase is of a SiO2 high-entropy alloy core-shell structure. The SiO2 shell in the reinforced phase plays roles in two aspects, on one hand, high-entropy alloy particles are effectively prevented from being decomposed under the laser high-energy density, on the other hand, a good interface structure is formed through SiO2 transition, the comprehensive performance such as corrosion resistance, tensile strength and hardness of the material is improved, and huge potential value is shown in multiple industrial application fields.

Description

Technical Field

[0001] The present invention relates to the technical field of the design and preparation of steel-based composite materials, and particularly relates to a high-entropy alloy reinforced stainless steel composite material and a selective laser additive manufacturing method thereof. Background Art

[0002] As an important alloy material, stainless steel is widely used in many fields such as chemical industry, construction, and medical devices due to its excellent corrosion resistance and processing convenience. However, the strength and hardness of stainless steel are still insufficient compared with some application requirements. Especially in environments with high loads and severe wear, its performance limitations have become the main factors restricting its application scope.

[0003] In order to improve the performance of stainless steel, researchers have adopted various methods, including alloying, heat treatment, surface treatment, and the preparation of composite materials. Liu Lilan et al. aimed to prepare a crack-free Ni60 alloy cladding layer on the surface of 316L stainless steel, optimized the cladding process parameters, summarized the influence rules of the parameters, and studied the microstructure and microhardness of the cladding layer, so that the obtained cladding layer was metallurgically bonded to the matrix, enhancing the mechanical properties of the material; Zhang Weiqiang et al. prepared Al2O3 reinforced ZrO2 (alumina reinforced zirconia, ARZ) ceramic particle reinforced 316L stainless steel (316L stainless steel / ARZ) composite materials by powder metallurgy process, and studied the influence of the volume fraction of ARZ ceramic particles on the microstructure, relative density, hardness, and wear resistance of 316L stainless steel / ARZ composite materials, and obtained the conclusion that when the volume fraction of ARZ ceramic particles was 60%, the hardness of the composite material reached the maximum value of HRB 96.8. At this time, the wear resistance of the composite material was improved compared with the 316L stainless steel matrix; Sun Ying et al. studied the influence of different annealing heat treatment processes on the tensile properties of selectively laser melted (SLMed) 316L stainless steel in different building directions. The research results showed that recrystallization occurred to varying degrees in the SLMed specimens in different building directions. The synergistic effect of fine grain strengthening, low dislocation density, and recrystallization promoted the improvement of the toughness and isotropy of the SLMed specimens in different building directions. Among them, alloying improves the performance of stainless steel by adding other elements, but this method is often costly and not very adaptable to the environment. Heat treatment can improve the mechanical properties of stainless steel, but the effect on increasing hardness and strength is limited. Surface treatment technologies, such as carburizing and nitriding, can improve the hardness and wear resistance of the stainless steel surface, but these methods often have a limited action depth and are difficult to meet the requirements of deep modification.

[0004] The preparation of composite materials is an effective way to improve the performance of stainless steel. By introducing hard particles such as tungsten carbide (WC), titanium carbide (TiC), borides, etc. into the stainless steel matrix as reinforcement phases, the hardness and strength of the material can be significantly improved. The combination of these hard particles and the stainless steel matrix is usually achieved by techniques such as powder metallurgy, thermal spraying or cladding. However, these traditional methods have some limitations, such as uneven particle distribution, weak interfacial bonding force, complex processing, etc., which limit the further improvement of the performance of composite materials.

[0005] In recent years, with the development of additive manufacturing technology, especially Selective Laser Melting (SLM) technology, new possibilities have been provided for the preparation of metal matrix composite materials. The SLM technology constructs three-dimensional parts by layer-by-layer melting and solidification of metal powders, and has the advantages of high processing accuracy, high material utilization rate, and the ability to manufacture parts with complex shapes. However, when using the SLM technology to prepare stainless steel composite materials, problems such as poor bonding between hard particles and the stainless steel matrix and difficulty in controlling interfacial reactions are faced.

[0006] To sum up, the above methods and research mainly use laser cladding technology or reinforcement phases such as aluminum alloys and ceramics to achieve the preparation of composite materials, and do not fundamentally solve problems such as uneven particle distribution and weak interfacial bonding force. In order to avoid the occurrence of the above problems, it is of engineering application significance to study stainless steel composite materials suitable for additive manufacturing and the appropriate additive manufacturing technology. Summary of the Invention

[0007] Aiming at the limitations in improving the performance of stainless steel composite materials in the prior art, the present invention provides a high-entropy alloy reinforced stainless steel composite material and its selective laser additive manufacturing method. By using HEA prefabricated powder coated with SiO2, the amorphous shell layer (SiO2) can effectively prevent the decomposition of HEA at temperatures above 800 °C after being directly heated by the laser during the high-energy laser sintering process, and improve the stability of the reinforcement phase during the manufacturing process.

[0008] To achieve the above object, the technical solutions adopted by the present invention are as follows:

[0009] A high-entropy alloy reinforced stainless steel composite material is composed of a stainless steel matrix and reinforcement phases dispersed in the stainless steel matrix. The reinforcement phases are core-shell structures (oxide ceramic @ high-entropy alloy) formed with high-entropy alloy as the core and oxide ceramic as the shell layer; the stainless steel matrix and the high-entropy alloy particles are separated by the oxide ceramic shell layer.

[0010] Furthermore, the high-entropy alloy particles are spherical or near-spherical powders with a body-centered cubic (BCC) solid solution structure, and the particle size is 15 - 53 μm; the oxide shell layer is SiO2.

[0011] Furthermore, the high-entropy alloy particles are preferably a FeCoNiCr(M)x high-hardness alloy system, where M is Al and / or Ti, and 0.7 < x < 2. The high-entropy alloy particles have excellent mechanical properties such as high strength, high hardness, low elastic modulus, and large elastic strain limit.

[0012] Furthermore, in this composite material, the proportion of the high-entropy alloy particles is 5-50 wt%; the thickness of the oxide shell layer is 5-15 nm, and the oxide shell layer (SiO2) is coated on the surface of the high-entropy alloy powder by hydrolysis of tetraethyl orthosilicate under the catalysis of ammonia water; the shell layer has the function of preventing the mutual melting and diffusion between the high-entropy alloy and stainless steel under high laser energy density.

[0013] Furthermore, for the method of selective laser additive manufacturing of the high-entropy alloy ceramic particle-reinforced stainless steel composite material, this method uses selective laser additive manufacturing technology to manufacture the composite material, and its manufacturing process includes the following steps:

[0014] (1) Raw material selection: Prepare high-entropy alloy powder and stainless steel powder;

[0015] (2) Preparation of the core-shell structured reinforcing phase: Weigh a certain amount of high-entropy alloy powder (HEA powder) and put it into an electric stirrer, add an appropriate amount of absolute ethanol, and stir for more than 20 minutes to mix evenly; then add an appropriate amount of tetraethyl orthosilicate (TEOS) and deionized water and stir for 1 hour; then add the catalyst ammonia water and continuously stir for 3-8 hours; after in-situ reaction, finally obtain the core-shell structured oxide ceramic@high-entropy alloy prefabricated powder, that is, the reinforcing phase;

[0016] (3) Carry out low-temperature drying treatment on the prefabricated powder obtained in step (2);

[0017] (4) Mix the prefabricated powder treated in step (3) with the stainless steel powder according to the required ratio to obtain the composite powder for selective laser additive manufacturing;

[0018] (5) Use selective laser additive manufacturing technology to perform additive manufacturing and forming on the cladding powder obtained in step (4) to obtain the HEA-reinforced stainless steel composite material.

[0019] Furthermore, in step (2), the ratio of tetraethyl orthosilicate to the high-entropy alloy powder is (5-20) ml: 100 g, and 3-15 ml of ammonia water, 100-200 ml of absolute ethanol, and 5-35 ml of deionized water are added to every 100 g of high-entropy alloy powder.

[0020] Further, in step (2), the high-entropy alloy powder is spherical or approximately spherical powder with a particle size range of 15 - 53 μm; the purity of the stainless steel powder is > 99.9%, and the particle size is 15 - 53 μm; the ammonia water, tetraethyl orthosilicate, and absolute ethanol are all of analytical purity.

[0021] Further, in step (2), the rotation speed of the electric stirrer is controlled at 50 - 100 r / min to obtain uniform SiO2-coated high-entropy alloy powder; during the construction of the core-shell structure, when coating SiO2 on the surface of the high-entropy alloy powder, the addition amount of tetraethyl orthosilicate (TEOS) is controlled to obtain a SiO2 shell layer thickness of 5 - 15 nm.

[0022] Further, in step (3), the time of the low-temperature drying treatment is 6 - 10 h, and the temperature is 50 - 80 °C; in step (4), the mixing process can be carried out in a powder mixer, a ball mill, or a vibrating sieve.

[0023] Further, when performing additive manufacturing and forming in step (5), according to the external dimensions of the component, after three-dimensional modeling by UG and STL data conversion, the printing parameters are set as follows: the powder spreading thickness is 30 - 70 μm (preferably 30 - 50 μm), the laser power is 200 - 280 W (preferably 210 - 250 W), the scanning speed is 800 - 1200 mm / s, and the oxygen content in the working chamber is controlled at ≤ 0.1 wt.%.

[0024] The additive manufacturing formed composite material parts obtained in the above step (5) can be post-treated, such as aging treatment or hot isostatic pressing treatment, to further improve the density and performance of the material.

[0025] The design mechanism of the present invention is as follows:

[0026] The present invention uses common stainless steel spherical powder as the matrix material for additive manufacturing composite components, designs and adds a certain proportion of HEA particles to prepare a composite material with high strength, high hardness, wear resistance, and corrosion resistance. The in-situ generation method is used to coat SiO2 to form a core-shell structure of HEA prefabricated powder. During the laser high-energy sintering process, the amorphous shell layer (SiO2) can effectively prevent the decomposition of HEA at temperatures above 800 °C after being directly heated by the laser, and improve the stability of the reinforcing phase during the manufacturing process. Therefore, through selective laser additive manufacturing, the present invention obtains HEA high-entropy alloy particle-reinforced composite material additive manufacturing formed parts with a stainless steel@HEA composite structure, corrosion resistance, wear resistance, and adjustable volume fraction of the reinforcing phase.

[0027] The advantages and beneficial effects of the present invention are as follows:

[0028] 1. The composite material parts formed by direct selective laser printing in the present invention use common stainless steel spherical powder as the alloy matrix, which can reduce the cost of using alloy materials.

[0029] 2. In the composite material with a core-shell structure as the reinforcing phase in the present invention, the HEA high-entropy alloy particles as the core are high-strength and high-hardness materials, and the shell material is SiO2 obtained by in-situ reaction.

[0030] 3. The microstructure of the composite material obtained by selective laser forming in the present invention is a stainless steel@HEA composite structure. Through the oxide ceramic shell layer SiO2 as an intermediate transition, a composite material with good interfacial bonding is obtained, which is beneficial for load transfer, has good toughness while improving the material strength.

[0031] 4. During the preparation of the composite material parts formed by direct selective laser printing in the present invention, in the in-situ generation of SiO2 reaction, the thickness of the oxide ceramic shell layer in the prepared stainless steel@oxide ceramic@HEA structure is controlled by controlling the amount of tetraethyl orthosilicate added.

[0032] 6. The composite material parts prepared in the present invention can achieve the purpose of high strength, high hardness, wear resistance, and corrosion resistance of the material. First, the stainless steel@oxide ceramic@HEA composite structure of the prepared parts replaces the existing stainless steel@HEA structure, which can prevent the high-temperature decomposition of HEA; second, by using direct selective laser printing for forming, additive manufacturing of parts can be realized in one step, reducing processing time and material loss.

[0033] 7. The present invention prepares an HEA high-entropy alloy-reinforced stainless steel composite material suitable for selective laser additive manufacturing, which has characteristics such as high hardness, high wear resistance, and corrosion resistance, and can be widely used in the preparation of key components in the deep-sea and deep-earth oil industries. Description of the Drawings

[0034] Figure 1 SEM image of the stainless steel spherical powder used in Example 1.

[0035] Figure 2 SEM image of the high-entropy alloy in Example 1.

[0036] Figure 3 Microstructure of the high-entropy alloy-reinforced stainless steel composite material prepared by selective laser additive manufacturing in Example 1; where: (a) and (b) have different contrasts.

[0037] Figure 4 Mechanical properties of the HEA-reinforced stainless steel composite material prepared by selective laser additive manufacturing in Example 1.

[0038] Figure 5For the wear performance (mainly oxidative wear) of the HEA-reinforced stainless steel composite material fabricated by selective laser additive manufacturing in Example 1, where: (a) is the SEM image of the worn surface; (b) is the friction coefficient; (c) is the three-dimensional diagram of the wear scar depth; (d) is the cross-sectional diagram of the wear scar depth (friction load 60 N, friction frequency 3 Hz). Detailed implementation manners

[0039] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, so that those skilled in the art can better understand the present invention and be able to implement it, but the specific embodiments cited are not intended to limit the present invention.

[0040] High-entropy alloy (HEA) is a new type of alloy material. Due to its multi-element composition, it exhibits excellent comprehensive properties, including high strength, high hardness, good corrosion resistance, and anti-wear performance. If HEA is introduced as a reinforcing phase into the stainless steel matrix, it is expected to significantly improve the overall performance of the composite material. However, the diffusion of HEA with similar melting points in the stainless steel matrix and the interfacial bonding force are still key issues to be solved.

[0041] The motivation of the present invention is to combine the high strength and high hardness characteristics of high-entropy alloy with the excellent mechanical properties and corrosion resistance of stainless steel, and through an innovative core-shell structure design and selective laser additive manufacturing technology, prepare a composite material with better comprehensive performance. The composite material of the present invention is particularly suitable for application scenarios requiring high strength and high hardness, such as deep-sea operations, aerospace, and petrochemical industries, which have extremely high requirements for the mechanical properties and wear resistance of materials.

[0042] Another object of the present invention is to solve the problem of mutual solubility existing when high-entropy alloy materials are combined with metal matrices in the prior art, as well as the problem of performance degradation during application in high-load and wear environments. By adopting the core-shell structure design, the present invention not only improves the dispersion uniformity of the high-entropy alloy reinforcing phase in the stainless steel matrix, but also enhances the interfacial bonding force between them, thereby ensuring the stability and reliability of the overall performance of the composite material.

[0043] In addition, the present invention also aims to precisely control the microstructure and macroscopic properties of the magnetic composite material through selective laser additive manufacturing technology. The application of this technology makes the preparation process of the composite material more flexible, and the properties of the material can be customized according to specific application requirements to achieve the optimal configuration of material properties.

[0044] The present invention provides a high-entropy alloy HEA-reinforced stainless steel composite material and a selective laser additive manufacturing method thereof. The prefabricated powder with a core-shell structure is prepared by an in-situ generation method, and then the HEA high-entropy alloy-reinforced stainless steel composite material is prepared through selective laser additive manufacturing technology.

[0045] The high-entropy alloy reinforced stainless steel composite material is composed of a reinforcing phase and a stainless steel matrix. The reinforcing phase has a core-shell structure with spherical or approximately spherical HEA powder as the core and oxide ceramic (SiO2) as the shell. An interface bond is formed between the stainless steel matrix and the high-entropy alloy powder through an oxide ceramic (SiO2) transition layer.

[0046] The shell material in the reinforcing phase is an amorphous SiO2 shell obtained through the hydrolysis reaction of tetraethyl orthosilicate. By controlling the concentration, content of tetraethyl orthosilicate, and reaction process parameters, the regulation of the shell thickness (5 - 15 nm) is achieved.

[0047] The matrix of the printed composite component is spherical stainless steel powder material prepared by the melt atomization method, and the particle size of the stainless steel powder is 15 - 53 μm.

[0048] In this composite material, the mass fraction range of the high-entropy alloy powder is 5 - 50 wt%.

[0049] The selective laser additive manufacturing method for the high-entropy alloy ceramic particle reinforced stainless steel composite material includes the following steps:

[0050] (1) Raw material preparation: Weigh AlFeCrCoNi metal powder with a particle size of 15 - 53 μm; prepare stainless steel powder with a particle size of 15 - 53 μm.

[0051] (2) Construction of the core-shell structure:

[0052] Coat SiO2 on the surface of the alloy powder to form a core-shell structure of SiO2@HEA, where the shell thickness is controlled within the range of 5 - 15 nm. Add ammonia water and tetraethyl orthosilicate. Under the catalytic action of ammonia water, tetraethyl orthosilicate undergoes a hydrolysis reaction and an SiO2 layer is in-situ generated on the surface of the alloy powder to enhance the stability of the core-shell structure.

[0053] (3) Dry the prefabricated powder with the core-shell structure obtained after the hydrolysis reaction at a low temperature of 80 °C for 4 hours;

[0054] (4) Mechanically mix the prefabricated powder obtained after low-temperature drying in step (3) with stainless steel powder. The mixing process can be carried out in a powder mixer, ball mill, or vibrating sieve. After mixing for 20 - 60 min, the cladding powder suitable for selective laser additive manufacturing is obtained.

[0055] (5) Carry out additive manufacturing and forming on the cladding powder obtained in step (4). During forming, according to the external dimensions of the component, after three-dimensional modeling by UG and STL data conversion, the printing parameters are set as follows: powder spreading thickness 30 - 70 μm, laser power 220 W, scanning speed 400 - 1200 mm / s, and the oxygen content in the working chamber ≤ 0.1 wt.%.

[0056] In the following examples, the 316L stainless steel powder raw material used is a commonly used spherical stainless steel powder for additive manufacturing ( Figure 1 ), and the high-entropy alloy powder is an approximately spherical powder ( Figure 2 ). The particle sizes of both materials are 15 - 53 μm.

[0057] Example 1:

[0058] This example is for the preparation of a high-entropy alloy particle-reinforced stainless steel composite, designing a composite powder of 316L stainless steel and high-entropy alloy powder. According to the equipment specifications of the 3D metal printer used in this example and the height of the designed component, the mass of the high-entropy alloy used is 250 g, and the stainless steel powder is 2750 g. The weighed high-entropy alloy powder and stainless steel powder are processed. The stainless steel powder is dried at low temperature, and the high-entropy alloy is prepared with a core-shell structure. The specific steps are as follows:

[0059] 1. Raw material weighing: Accurately weigh the AlFeCrCoNi high-entropy alloy powder with a particle size of 15 - 53 μm; prepare the stainless steel powder with a particle size of 15 - 53 μm.

[0060] 2. Take 250 g of high-entropy alloy powder and place it in an electric stirrer, add 300 ml of absolute ethanol, and stir well for 30 minutes; then add 50 ml of deionized water, 30 ml of tetraethyl orthosilicate (TEOS), and 25 ml of ammonia water, and stir mechanically for 4 hours to obtain the SiO2@high-entropy alloy prefabricated powder. After drying at 70 °C for 8 h, it is ready for use. During the stirring process, the rotation speed of the electric stirrer is 75 r / min.

[0061] 3. Powder mixing: Mix the core-shell structure powder prepared in step (2) with the 316L stainless steel powder according to the mass design composition in step 1 to ensure uniform dispersion, obtaining the cladding powder for laser selective area additive manufacturing.

[0062] 6. Laser selective area additive manufacturing: Use a laser selective area additive manufacturing device, set the laser power to 220 W, the scanning speed to 800 mm / s, the powder spreading thickness to 30 μm, and control the oxygen content in the working chamber to be below 0.1 wt.%, to manufacture the composite material part with the required shape.

[0063] Test the composite block sample obtained in step 6.

[0064] Figure 3 For the microstructure of the high-entropy alloy-reinforced stainless steel composite prepared by laser selective area additive manufacturing in Example 1, it can be seen from Figure 3 that the interface between the ceramic phase and the stainless steel is tightly bonded, and there is a transition layer. The thickness of the transition layer SiO2 is 8 - 15 nm.

[0065] Figure 4For the tensile properties of the high-entropy alloy reinforced stainless steel composite prepared by selective laser additive manufacturing in Example 1, it can be seen from Figure 4 that the yield strength of the additively manufactured HEA reinforced 316L composite material is 625±2 mpa, the fracture strength is 697±2 MPa, and the elongation is 33.2±0.1%.

[0066] Figure 5 For the friction and wear properties of the HEA reinforced stainless steel composite prepared by selective laser additive manufacturing in Example 1, it can be seen from Figure 5 that under the friction load of 30 N, the friction frequency of 3 Hz, and the friction time of 20 minutes, the friction mechanism of the composite material is mainly oxidative wear, and the friction coefficient is stable at about 0.5.

[0067] Example 2:

[0068] The difference from Example 1 is that the designed weight ratio of 316L stainless steel powder to high-entropy alloy powder in the composite material is 12:88; the parameters of selective laser additive manufacturing are optimized: the laser power is adjusted to 240 W, and the scanning speed is adjusted to 1000 mm / s to study the influence of different laser parameters on the forming quality of the composite material.

[0069] The remaining process conditions are the same as those in Example 1. The thickness of the transition layer SiO2 between the high-entropy alloy and the stainless steel matrix in the obtained composite powder is 8-15 nm.

[0070] Then, a composite material specimen is formed by selective laser additive manufacturing according to the process of Example 1. In this composite material, the reinforcing phase is dispersedly distributed in the stainless steel matrix, and the stainless steel matrix and the high-entropy alloy particles are separated by the oxide ceramic shell layer.

Claims

1. A high-entropy alloy reinforced stainless steel composite material, characterized in that: The composite material is composed of a stainless steel matrix and reinforcing phases dispersed in the stainless steel matrix. The reinforcing phases are core-shell structures with high-entropy alloy particles as the core and oxide ceramics as the shell layer, and the stainless steel matrix is separated from the high-entropy alloy particles by the oxide ceramic shell layer.

2. The high-entropy alloy particle-reinforced stainless steel composite material according to claim 1, characterized in that: The high-entropy alloy particles are spherical or near-spherical powders with a body-centered cubic (BCC) solid solution structure, and the particle size is 15 - 53 μm; the oxide shell layer is SiO2.

3. The high-entropy alloy particle-reinforced stainless steel composite material according to claim 1, characterized in that: The high-entropy alloy particles are a FeCoNiCr(M)x high-hardness alloy system, where M is Al and / or Ti, and 0.7 < x < 2.

4. The high-entropy alloy reinforced stainless steel composite material according to claim 1, characterized in that: In this composite material, the proportion of the high-entropy alloy particles is 5 - 50 wt%; the thickness of the oxide shell layer is 5 - 15 nm, and the shell layer has the function of preventing the high-entropy alloy from melting after absorbing laser and interdiffusing with the stainless steel to form an alloy, thus losing the structure of the high-entropy alloy reinforcing phase.

5. The selective laser additive manufacturing method of the high-entropy alloy reinforced stainless steel composite material according to any one of claims 1-4, characterized in that: This method uses laser selective additive manufacturing technology to manufacture the composite material, and its manufacturing process includes the following steps: (1) Raw material selection: Prepare high-entropy alloy powder and stainless steel powder; (2) Preparation of the core-shell structured reinforcing phase: Weigh a certain amount of high-entropy alloy powder and place it in an electric stirrer, add an appropriate amount of absolute ethanol, and stir for more than 20 minutes to mix evenly; then add tetraethyl orthosilicate (TEOS) and deionized water and stir for 1 hour, and then add an appropriate amount of ammonia water and stir for 3 - 8 hours; finally, through in-situ reaction, the oxide ceramic@high-entropy alloy prefabricated powder with a core-shell structure, that is, the reinforcing phase, is obtained. (3) Carry out low-temperature drying treatment on the prefabricated powder obtained in step (2); (4) After fully mixing the prefabricated powder treated in step (3) with the stainless steel powder in the required proportion, obtain the cladding powder for laser selective additive manufacturing; (5) Use laser selective additive manufacturing technology to perform additive manufacturing and shaping on the cladding powder obtained in step (4) to obtain a high-entropy alloy reinforced stainless steel composite material.

6. The selective laser additive manufacturing method of the high-entropy alloy reinforced stainless steel composite material according to claim 5, characterized in that: In step (2), the ratio of tetraethyl orthosilicate to high-entropy alloy powder is (5 - 20) ml:100 g, and 3 - 15 ml of ammonia water, 100 - 200 ml of absolute ethanol, and 5 - 35 ml of deionized water are added to every 100 g of high-entropy alloy powder.

7. The selective laser additive manufacturing method of the high-entropy alloy reinforced stainless steel composite material according to claim 5, wherein: In step (2), the high-entropy alloy powder is spherical or approximately spherical powder, and the particle size range is 15 - 53 μm; the purity of the stainless steel powder > 99.9%, and the particle size is 15 - 53 μm; the ammonia water, tetraethyl orthosilicate, and absolute ethanol are all of analytical purity.

8. The selective laser additive manufacturing method of the high-entropy alloy reinforced stainless steel composite material according to claim 5, characterized in that: In step (2), the rotation speed of the electric stirrer is 50 - 100 r / min; in the in-situ reaction, the thickness of the oxide ceramic shell layer is controlled at 5 - 15 nm by controlling the addition amount of tetraethyl orthosilicate.

9. The selective laser additive manufacturing method of the high-entropy alloy reinforced stainless steel composite material according to claim 5, characterized in that: In step (3), the treatment temperature of the low-temperature drying treatment is 50 - 80 °C, and the treatment time is 6 - 10 h; in step (4), the mixing process is carried out by using a powder mixer, a ball mill, or a vibrating sieve.

10. The selective laser additive manufacturing method of the high-entropy alloy reinforced stainless steel composite material according to claim 5, characterized in that: When performing additive manufacturing in step (5), according to the external dimensions of the component, after three-dimensional modeling in UG and STL data conversion, the printing parameters are set as follows: powder spreading thickness 30 - 70 μm, laser power 200 - 280 W, scanning speed 800 - 1200 mm / s, and the oxygen content in the working chamber ≤ 0.1 wt.%.

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