High-entropy alloy composite coating with high atomic number and low atomic number matched and preparation method and application of high-entropy alloy composite coating

Abstract

The invention discloses a high-entropy alloy composite coating with matched high and low atomic numbers and a preparation method of the high-entropy alloy composite coating, and belongs to the technical field of functional materials and preparation of the functional materials. The problem that an existing high-entropy alloy composite coating has a weak radiation depletion region is solved. Light atoms with small atomic sizes are doped in metal gaps in a gap filling mode through cooperation of high atomic numbers and low atomic numbers, electrons are effectively prevented from directly penetrating through energy loss gaps in the gaps, and therefore the shielding performance of the light atoms on high-energy electrons is improved; and the influence of a radiation depletion weak region of the existing high-entropy alloy on the radiation shielding efficiency is made up. The doping of the light atoms can influence the state of electrons around the metal, so that the electrons can form a denser electron region around the light atoms, the collision probability of the electrons in unit cells is increased, the maximization of non-elastic collision of extranuclear electrons is realized, and the protection performance of the composite material on the electrons is further improved; therefore, the tolerance of the device in high-energy electrons is improved.

Description

Technical Field

[0001] The present invention relates to a high-entropy alloy composite coating with high and low atomic numbers, a preparation method and application thereof, and belongs to the technical field of functional materials and their preparation. Background Art

[0002] Metal oxide semiconductor field-effect transistors (MOSFETs), core components in commercial aerospace, exhibit significant vulnerability to the complex radiation environment of space. While aerospace-grade MOSFETs offer specific environmental adaptability, their high manufacturing costs and lengthy manufacturing cycles further limit their development in the aerospace sector. Therefore, implementing effective radiation hardening methods is crucial to achieving the spaceflight application of commercial devices.

[0003] There are three methods for radiation hardening devices: process hardening, design hardening, and package hardening. Package hardening can prevent radiation from directly hitting the device, and has the advantages of low cost and high shielding efficiency. Common package hardening materials include metals, ceramics, and polymer-based composites. Polymer-based composites are ideal candidates for package hardening of MOSFET devices due to their flexible molding and light weight.

[0004] The radiation shielding efficiency of polymer-based composites primarily depends on the functional filler. High-entropy alloys (HEAs) have become a research hotspot for extreme environments due to their multi-component synergistic effects and entropy stabilization, offering new opportunities for the design of radiation-shielding functional fillers. HEAs can be broadly categorized as conventional HEAs and refractory RHEAs. RHEAs, composed of refractory metals such as W, Ta, Nb, Mo, and Cr, possess abundant extranuclear electrons and excellent radiation shielding efficiency. Research has focused on optimizing the radiation shielding properties of RHEAs through compositional engineering (e.g., element selection and concentration adjustment). Lattice distortion, induced by atomic size differences and chemical complexity, has been found to enhance the radiation shielding efficiency of HEAs to a certain extent. However, the unoccupied octahedral / tetrahedral interstices in the randomly stacked structure still form weak radiation depletion regions. Therefore, further modification of HEAs is crucial for enhancing the radiation resistance of their composite coatings for commercial electronic components. Summary of the Invention

[0005] In order to solve the problem of weak radiation depletion zone in existing high entropy alloy composite coatings, the present invention provides a high entropy alloy composite coating with high and low atomic numbers, a preparation method and application thereof.

[0006] The technical solution of the present invention:

[0007] One of the purposes of the present invention is to provide a method for preparing a high-entropy alloy composite coating having a combination of high and low atomic numbers, the method comprising the following steps:

[0008] (1) Tantalum powder, tungsten powder, niobium powder, molybdenum powder, and chromium powder are mixed, a light atom modifier is added, and ball milling is performed to obtain a mixed powder;

[0009] (2) The mixed powder is laser melted, crushed, and ball-milled to obtain high entropy powder;

[0010] (3) The high entropy powder is mixed with a resin matrix, coated into a film, and then heated and dried to obtain a light atom modified high entropy alloy composite coating.

[0011] It is further defined that the molar ratio of tantalum powder, tungsten powder, niobium powder, molybdenum powder and chromium powder in (1) is 1:1:1:1:1.

[0012] It is further defined that the light atom modifier in (1) is carbon powder, boron powder, boron nitride powder or boron carbide powder.

[0013] It is further defined that the amount of the light atom modifier added in (1) is 0-5% of the total molar amount of tantalum powder, tungsten powder, niobium powder, molybdenum powder and chromium powder.

[0014] It is further defined that the ball milling time in (1) is 6-48h, the rotation speed is 200-900r / min, and the ball-to-material ratio is (1-40):1.

[0015] It is further defined that the laser power in (2) is 500-1200W.

[0016] It is further defined that the ball milling speed in (2) is 200-900 r / min and the time is 1-12 h.

[0017] It is further defined that (2) the medium-high entropy powder accounts for 5-50% of the total mass of the coating, the drying temperature is 60°C and the drying time is 5 hours, and the coating thickness is 0.1-2 mm.

[0018] A second object of the present invention is to provide a high entropy alloy composite coating prepared by the above method.

[0019] A third object of the present invention is to provide an application of the above-mentioned high entropy alloy composite coating, specifically for radiation-resistant packaging hardening of devices.

[0020] Beneficial effects:

[0021] The present invention utilizes the smaller atomic size of light atoms (C, N)) and utilizes high and low atomic numbers to dope them in the form of gap filling in the metal gap, which plays the role of lattice strengthening, providing sites, electronic regulation, etc., to prevent the energy loss gap of electrons from passing directly through the gap, thereby improving its shielding performance for high-energy electrons, and compensating for the influence of the radiation depletion weak area on the radiation shielding efficiency of the existing high-entropy alloy. In addition, the doping of light atoms will also affect the electronic state around the metal, so that the electrons realize a denser electronic region around the light atoms, increase the collision probability of the electrons in the unit cell, and maximize the inelastic collision of the extranuclear electrons, further improving the protection performance of the composite material to the electrons, thereby improving the tolerance of the device in high-energy electrons. In addition, the present invention adopts a ball milling mixing process and a melting process to realize the preparation of the composite coating, which is easier to realize the regulation of the type of light atoms and the amount of light atom incorporation, and has the advantages of simple and easy regulation of the preparation process. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 XRD pattern of 4% C-doped CrNbMoTaW high entropy alloy prepared in Example 1;

[0023] Figure 2 Raman graphs of the 4% C-doped CrNbMoTaW high-entropy alloy prepared in Example 1 and the CrNbMoTaW high-entropy alloy prepared in Comparative Example 1;

[0024] Figure 3 This is the XRD pattern of the 4% B-doped CrNbMoTaW high-entropy alloy prepared in Example 2;

[0025] Figure 4 XRD pattern of 4% B4C-doped CrNbMoTaW high entropy alloy prepared in Example 3;

[0026] Figure 5 This is a SEM image of the 4% C-doped CrNbMoTaW high-entropy alloy prepared in Example 1;

[0027] Figure 6 This is a SEM image of the 4% B-doped CrNbMoTaW high-entropy alloy prepared in Example 2;

[0028] Figure 7 The transfer curves of electronic components encapsulated in high entropy alloy / epoxy resin composite coatings prepared in Examples 1 and 2 are shown;

[0029] Figure 8 This is the electron density distribution diagram of the 4% C-doped CrNbMoTaW high entropy alloy prepared in Example 1. DETAILED DESCRIPTION

[0030] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the embodiments of the specification.

[0031] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0032] Secondly, the term "one embodiment" or "embodiment" herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in various places throughout this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive of other embodiments.

[0033] The experimental methods used in the following examples are conventional methods unless otherwise specified. The materials, reagents, methods, and instruments used are conventional in the art and can be obtained commercially by those skilled in the art unless otherwise specified.

[0034] Example 1:

[0035] (1) The preparation of pre-alloyed powder is as follows:

[0036] A mixture of metal powders (tantalum powder, tungsten powder, niobium powder, molybdenum powder, and chromium powder) in an equal molar ratio of 1:1:1:1:1 was added to carbon powder (4% of the total molar weight of tantalum, tungsten, niobium, molybdenum, and chromium powders) as the milling material. The mixed powders were added to a ball mill jar. Based on the size of the mill, a ball-to-material ratio of 20:1 was determined. The jar was placed in a ball mill, and argon was introduced as a protective gas for 5 minutes. The mill was milled at a speed of 600 rpm for 12 hours. After completion of the milling, the balls and materials were separated. After separation, the powders were dried in a vacuum drying oven at 60°C for 5 hours.

[0037] (2) Synthesis of high entropy powder:

[0038] The mixed powder prepared in (1) was melted by a laser with a power of 800W. After the molten metal blocks were broken, the powder particles were further refined by a ball mill. The ball milling time was set to 10h and the ball milling speed was set to 500rpm. The obtained high entropy powder was named HEA-C. 4％ .

[0039] (3) Preparation of composite coating:

[0040] According to the ratio of powder to the total mass of the composite coating of 20%, the high entropy powder prepared in (2) is mixed with the epoxy resin matrix and fully ground and mixed using a three-roll grinder. The grinding time can be controlled at 5 minutes according to the powder content. After grinding, the mixed slurry is coated on the surface of the device with a coating thickness of 1 mm, and then placed in a vacuum drying oven and dried at 60°C for 6 hours.

[0041] Example 2:

[0042] The difference between this embodiment and embodiment 1 is that: (1) boron powder is used instead of carbon powder, and the remaining process steps and parameter settings are the same as those in embodiment 1. The obtained high entropy powder is named HEA-B 4％ .

[0043] Example 3:

[0044] The difference between this embodiment and embodiment 1 is that: (1) boron carbide powder is used instead of carbon powder, and the remaining process steps and parameter settings are the same as those in embodiment 1. The obtained high entropy powder is named HEA-4%B4C.

[0045] Example 4:

[0046] The difference between this embodiment and embodiment 1 is that: (1) the carbon powder accounts for 6% of the total molar amount of tantalum powder, tungsten powder, niobium powder, molybdenum powder and chromium powder, and the remaining process steps and parameter settings are the same as those in embodiment 1.

[0047] Comparative Example 1:

[0048] The difference between this comparative example and Example 1 is that: in (1), no carbon powder was added, and the remaining process steps and parameter settings were the same as those in Example 1. The obtained high entropy powder was named HEA.

[0049] Effect example:

[0050] (1) The high entropy powders prepared in Examples 1 to 3 and Comparative Example 1 were characterized by XRD and Raman. The results are as follows: Figures 1 to 4 As shown in the figure, it can be seen that C does not exist in the form of a compound, but enters the high entropy alloy lattice in the form of an interstitial space; the 4% B material fails to be completely incorporated into the high entropy alloy interstitial space, which may be due to the fact that B The atomic size of C Larger cause.

[0051] (2) The micromorphology of the composite coatings prepared in Examples 1 and 2 was characterized, and the SEM photos are shown in FIG. Figure 5 and 6 As shown in the figure, it can be seen that the high entropy alloy powders after ball milling are all at the micron level, so there is no problem of sedimentation affecting performance testing due to excessive size.

[0052] (3) The shielding performance of the composite coatings prepared in Examples 1 and 2 was characterized. Specifically, the coatings prepared in Examples 1 and 2 were used to encapsulate the surface of electronic devices, and the electrochemical parameters of the electronic devices were tested before and after irradiation (500 krad, energy of 1 MeV). The test results are shown in FIG. Figure 7 As shown in the figure, it can be seen that the threshold voltage of the MOSFET device changes from 3.02V to 0.04V after irradiation, and the turn-on voltage of the device decreases due to the total dose effect; the carbon-doped high-entropy alloy composite coating encapsulated MOSFET device has a smaller threshold voltage change than the boron-doped high-entropy alloy composite coating encapsulated MOSFET device, which proves that the coating prepared in Example 1 has excellent radiation resistance.

[0053] (4) Figure 8 This is the electron density distribution diagram of the 4% C-doped CrNbMoTaW high-entropy alloy prepared in Example 1. It can be seen from the figure that carbon interstitial doping induces the transfer of local electrons to carbon, and the local electron density increases, thereby improving the protection performance against incident electrons.

[0054] The above description is merely a preferred embodiment of the present invention. Given that those skilled in the art can make appropriate changes and modifications to the above embodiments, the present invention is not limited to the specific embodiments described above. Some modifications and changes to the present invention should also fall within the scope of protection of the claims of the present invention.

Claims

1. A method for preparing a high-entropy alloy composite coating with high and low atomic numbers, characterized in that: include: (1) Tantalum powder, tungsten powder, niobium powder, molybdenum powder, and chromium powder are mixed, a light atom modifier is added, and ball milling is performed to obtain a mixed powder; (2) The mixed powder is laser melted, crushed, and ball-milled to obtain high entropy powder; (3) The high entropy powder is mixed with a resin matrix, coated into a film, and then heated and dried to obtain a light atom modified high entropy alloy composite coating.

2. The preparation method according to claim 1, characterized in that (1) The molar ratio of tantalum powder, tungsten powder, niobium powder, molybdenum powder and chromium powder is 1:1:1:1:

1.

3. The preparation method according to claim 1, characterized in that (1) The medium-light atom modifier is carbon powder, boron powder, boron nitride powder or boron carbide powder.

4. The preparation method according to claim 1, characterized in that (1) The amount of the medium-light atom modifier added is 0-5% of the total molar amount of tantalum powder, tungsten powder, niobium powder, molybdenum powder and chromium powder.

5. The preparation method according to claim 1, characterized in that (1) The ball milling time is 6-48h, the rotation speed is 200-900r / min, and the ball-to-material ratio is (1-40):

1.

6. The preparation method according to claim 1, characterized in that (2) Medium laser power is 500-1200W.

7. The preparation method according to claim 1, characterized in that (2) The ball milling speed is 200-900 r / min and the time is 1-12 h.

8. The preparation method according to claim 1, characterized in that (2) The medium-high entropy powder accounts for 5-50% of the total mass of the coating, the drying temperature is 60°C and the drying time is 5 hours, and the coating thickness is 0.1-2 mm.

9. A high entropy alloy composite coating prepared by the method according to any one of claims 1 to 8.

10. An application of the high entropy alloy composite coating according to claim 9, characterized in that: Radiation-resistant packaging hardening for devices.

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