Tungsten-based heavy alloy surface-coated stainless steel component and preparation method and application thereof

Abstract

The invention discloses a tungsten-based heavy alloy surface-coated stainless steel component and a preparation method and application thereof, and belongs to the technical field of metal connection. The preparation method of the component with the tungsten-based heavy alloy surface coated with the stainless steel comprises the following steps that a transition layer is additionally attached to the surface of tungsten-nickel-iron alloy; the tungsten-nickel-iron alloy with the transition layer and austenitic stainless steel are assembled, and a sheath assembly is obtained; carrying out degassing and hot isostatic pressing treatment on the sheath assembly; according to the preparation method of the component coated with the stainless steel on the surface of the tungsten-based heavy alloy, the tungsten-based heavy alloy and the austenitic stainless steel are used as matrixes, and preparation of the component coated with the tungsten-based heavy alloy through the austenitic stainless steel is achieved through the method of combining hot isostatic pressure diffusion bonding and powder metallurgy. An existing technology that a stainless steel shell is used for protecting tungsten-based heavy alloy and an end socket is closed in an argon tungsten-arc welding mode is replaced, an original assembly gap is removed through metallurgical bonding, and the whole running-down system is more stable in operation and better in corrosion resistance.

Description

Technical Field

[0001] The invention relates to the technical field of metal connection, and in particular to a tungsten-based heavy alloy surface-coated stainless steel component and a preparation method and application thereof. Background Art

[0002] Tungsten and tungsten alloys have a series of excellent properties such as high density, high strength, good ductility, good toughness, and small thermal expansion coefficient, so they are widely used in aerospace inertial systems, weapons industry armor protection, balance components, and nuclear reactor radiation protection. Tungsten-nickel-iron alloy is a type of alloy with tungsten as the matrix and a small amount of Ni, Fe and other elements added. It is currently the largest tungsten-based heavy alloy with a density of up to 16.5g / cm 3 -20.0g / cm 3 .

[0003] Hot isostatic pressing is to place the assembled tungsten or tungsten alloy, stainless steel component products in a closed container, apply equal pressure in all directions to the component and apply high temperature at the same time. Under the combined action of high temperature and high pressure, the various parts of the component are diffusely connected at one time to form an integral component. Hot isostatic pressing diffusion bonding technology has the advantages of high connection strength, complete microstructure, small distortion, and the ability to connect different materials. Since the interface does not produce a liquid phase, the interface bonding strength is the same as that of the weak side parent material, and a good metallurgical bond can be achieved.

[0004] Tungsten-based heavy alloys are susceptible to corrosion in water and weak acid environments, and need to be coated with a layer of corrosion-resistant austenitic stainless steel on the surface to improve their corrosion resistance. Therefore, a welding method is needed to allow austenitic stainless steel to completely coat the tungsten-based heavy alloy and achieve a good combination of austenitic stainless steel and tungsten-based heavy alloy.

[0005] Due to the large differences in the properties of tungsten-nickel-iron / austenitic stainless steel (melting point, thermal conductivity, thermal expansion coefficient, etc.), joints directly connected by arc melting welding and brazing are very likely to produce brittle intermetallic compounds and carbides, and the joints will have large residual stresses, resulting in low mechanical properties of the welded joints, and it is difficult to achieve overall coating of the tungsten-based heavy alloy with austenitic stainless steel. Summary of the invention

[0006] The purpose of the present invention is to provide a tungsten-based heavy alloy surface-coated stainless steel component and its preparation method and application, so as to solve the technical problem that tungsten-based heavy alloy and austenitic stainless steel cannot be directly welded in the prior art and can only be used with the help of shell protection. This application method has an air gap between the tungsten-based heavy metal and the stainless steel, thereby affecting the smooth operation and service life of the idling system.

[0007] To achieve the above object, an embodiment of the present invention provides a method for preparing a tungsten-based heavy alloy surface-coated stainless steel component, comprising the following steps:

[0008] Adding a transition layer on the surface of the tungsten-nickel-iron alloy;

[0009] Assembling the tungsten-nickel-iron alloy with a transition layer and austenitic stainless steel to obtain a sheath component;

[0010] Degassing and hot isostatic pressing of the package assembly;

[0011] After hot isostatic pressing is completed, the jacket is removed.

[0012] In one of the preferred solutions of the present invention, the transition layer is a Ni transition layer, and the thickness of the transition layer is 10 μm-30 μm.

[0013] In one of the preferred solutions of the present invention, the transition layer is made by electroplating, spraying or vapor deposition.

[0014] One of the preferred solutions of the present invention is to assemble the tungsten-nickel-iron alloy with the transition layer and the austenitic stainless steel to obtain the sheath component, including: assembling the austenitic stainless steel and the tungsten-nickel-iron alloy by solid-solid diffusion connection.

[0015] One of the preferred schemes of the present invention is to assemble a tungsten-nickel-iron alloy with a transition layer and austenitic stainless steel to obtain a sheath component, including: filling austenitic stainless steel powder in the gap between the sheath and the tungsten-nickel-iron alloy component, and assembling the austenitic stainless steel and the tungsten-nickel-iron alloy by powder metallurgy.

[0016] One of the preferred schemes of the present invention is to assemble the tungsten-nickel-iron alloy with a transition layer and austenitic stainless steel to obtain a sheath assembly, including: using solid austenitic stainless steel to fix the position, filling the gaps between the austenitic stainless steel, the tungsten-nickel-iron alloy parts and the sheath with connecting powder, and realizing the assembly of the austenitic stainless steel and the tungsten-nickel-iron alloy by combining diffusion bonding and powder metallurgy.

[0017] One of the preferred solutions of the present invention, the degassing comprises: keeping the temperature at 350°C-550°C for 1h-6h, and the vacuum degree is ≤2×10 -3 Pa.

[0018] In one of the preferred solutions of the present invention, hot isostatic pressing comprises: maintaining the temperature at 1000° C.-1350° C. and the pressure at 100 MPa-150 MPa for 0.5 h-4 h.

[0019] In one of the preferred solutions of the present invention, removing the sheath comprises: removing the sheath by machining.

[0020] The invention also discloses a tungsten-based heavy alloy surface-coated stainless steel component, which is prepared by adopting the above-mentioned method for preparing a tungsten-based heavy alloy surface-coated stainless steel component.

[0021] The invention also discloses an application of a tungsten-based heavy alloy surface-coated stainless steel component, and the tungsten-based heavy alloy surface-coated stainless steel component is used for a nuclear power main pump flywheel balance block.

[0022] In summary, the beneficial effects of the present invention are:

[0023] 1. The preparation method of the tungsten-based heavy alloy surface-coated stainless steel component of the present invention uses tungsten-based heavy alloy and austenitic stainless steel as the matrix, and realizes the preparation of austenitic stainless steel-coated tungsten-based heavy alloy components through a method combining hot isostatic pressing diffusion bonding and powder metallurgy; and even if the tungsten-based heavy alloy parts have complex shaped special-shaped curved surfaces and sharp corners, good connection can be achieved, and the connection joint has good comprehensive performance.

[0024] 2. The method for preparing a stainless steel component coated on the surface of a tungsten-based heavy alloy of the present invention is also applicable to the coating of tungsten / tungsten alloy and austenitic stainless steel.

[0025] 3. In the preparation method of the tungsten-based heavy alloy surface-coated stainless steel component of the present invention, the assembly of the tungsten-nickel-iron alloy with a transition layer and the austenitic stainless steel can be achieved by solid-solid diffusion connection of austenitic stainless steel and tungsten-nickel-iron, or by directly filling austenitic stainless steel powder around the tungsten-nickel-iron component and connecting it through powder metallurgy; solid austenitic stainless steel can also be used to fix the position, and the rest of the part can be filled with powder, which is achieved by combining diffusion connection and powder metallurgy. The combined performance of all the above methods can meet the use requirements, and can be batch processed in the same hot isostatic pressing furnace, with simple process, high work efficiency, and suitable for large-scale production.

[0026] 4. The tungsten-based heavy alloy surface-coated stainless steel component prepared by the present invention can be used as a braking system and an idling inertia balancing component, which can ensure the integrity of the flywheel under overspeed conditions. At the same time, the surface is coated with austenitic stainless steel to meet the corrosion-resistant working conditions.

[0027] 5. The present invention is simple and convenient to prepare, has good bonding strength at each interface, no stress concentration, short production cycle, dense components, and can flexibly adjust the thickness of the surface stainless steel layer as needed.

[0028] 6. The preparation method of the tungsten-based heavy alloy surface-coated stainless steel component of the present invention can realize the one-time connection of corrosion-resistant material around the tungsten-based high-melting-point material, which cannot be accomplished by ordinary welding methods, and the preparation method of the present invention includes components with simple and complex structures, and can achieve it.

[0029] Other features and advantages of the present invention will be described in the following description, and part of them will become obvious from the description, or will be understood by implementing the present invention. The purpose and other advantages of the present invention can be described by the effects described in the description and the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic flow chart of the method for preparing a stainless steel component coated on the surface of a tungsten-based heavy alloy in the present invention;

[0031] Figure 2 Schematic diagram of a tungsten-based heavy alloy cladding component in an embodiment of the present invention;

[0032] Figure 3 This is a schematic diagram of the assembly of Example 1 of the present invention;

[0033] Figure 4 This is an electron microscope analysis picture of a stainless steel component coated on the surface of a tungsten-based heavy alloy prepared in Example 1 of the present invention;

[0034] Figure 5 This is a schematic diagram of the assembly of Example 2 of the present invention;

[0035] Figure 6 This is an electron microscope analysis image of a stainless steel component coated on the surface of a tungsten-based heavy alloy prepared in Example 2 of the present invention;

[0036] Figure 7 This is a schematic diagram of the assembly of Example 3 of the present invention;

[0037] Figure 8 This is an electron microscope analysis picture of the tungsten-based heavy alloy surface coated with a stainless steel component prepared in Example 3 of the present invention.

[0038] Among them, 1-package upper end cover, 2-304L plate, 3-package, 4-degassing hole, 5-tungsten alloy block, 6-package lower end cover, 7-304L powder, 8-ceramic positioning pin, 9-tungsten alloy column, 10-austenitic stainless steel, 11-tungsten or tungsten alloy substrate. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] The endpoints and any values ​​of the ranges disclosed in the present invention are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be regarded as specifically disclosed in the present invention.

[0041] The present invention provides a method for preparing a tungsten-based heavy alloy surface-coated stainless steel component, such as Figure 1 As shown, the following steps are included:

[0042] Step (1): adding a transition layer to the surface of the tungsten-nickel-iron alloy; specifically, the tungsten-nickel-iron alloy is surface treated, and the transition layer is added to the surface of the tungsten-nickel-iron alloy that has been surface treated by electroplating, spraying, vapor deposition, etc., wherein the transition layer is a Ni transition layer, and the thickness of the transition layer is 10 μm-30 μm; the tungsten-nickel-iron alloy here can also be tungsten / tungsten alloy, and various complex parts can add the transition layer to the surface of the tungsten / tungsten alloy, and the coating thickness is uniform;

[0043] Step (2): Assemble the tungsten-nickel-iron alloy with the transition layer and austenitic stainless steel to obtain a sheath component, wherein the austenitic stainless steel includes stainless steels of different grades such as 304, 316, 347, etc. Specifically, (1) for tungsten-nickel-iron alloy parts with simple shapes, such as cylinders, regular cubes, cuboids, etc. (excluding relatively many curved surfaces, steps, etc.), the austenitic stainless steel and the tungsten-nickel-iron alloy can be assembled by solid-solid diffusion bonding, and the austenitic stainless steel can be directly used as the sheath; (2) the austenitic stainless steel powder can also be filled in the gap between the sheath and the tungsten-nickel-iron alloy part, and the austenitic stainless steel can be realized by powder metallurgy. (3) solid austenitic stainless steel can also be used to fix the position, and the gaps between the austenitic stainless steel, the tungsten nickel iron alloy parts and the sheath are filled with connecting powder, and the austenitic stainless steel and the tungsten nickel iron alloy are assembled by a combination of diffusion bonding and powder metallurgy, wherein the connecting powder is the austenitic stainless steel powder to be coated, and different grades of stainless steel powder can be selected according to different needs; for the diffusion connection of solid and solid assembly, the connected stainless steel pipe can be directly used as the sheath, or a carbon steel or stainless steel sheath can be added; solid and solid diffusion connection can be made by argon arc welding, or electron beam welding, and powder metallurgy uses argon arc welding;

[0044] The sheath is made of A3 / Q235 steel; the chemical composition of the powder used in powder metallurgy needs to control the oxygen content; the surface of the austenitic stainless steel workpiece and the sheath is cleaned with alcohol or acetone before assembly to remove surface oil, foreign matter, etc., and compressed air is also required to blow dry;

[0045] Step (3): Degassing and hot isostatic pressing the package assembly; specifically, the assembled and welded package assembly is evacuated in a degassing furnace and degassed and insulated, the degassing temperature is controlled at 350°C-550°C, and the vacuum degree is ≤2×10 - 3 Pa, the holding time is 1h-6h, after the gas in the package is released, the package degassing port is sealed and welded to prevent the entry of air;

[0046] The degassed components are placed in a hot isostatic pressing furnace for hot isostatic pressing, so that the austenitic stainless steel blocks and powder are coated around the tungsten-nickel-iron alloy components; wherein the hot isostatic pressing process is: temperature 1000℃-1350℃, pressure 100MPa-150MPa, heat and pressure holding for 0.5h-4h, and different hot isostatic pressing process parameters can also be selected according to different grades and sizes;

[0047] Step (4): After the hot isostatic pressing is completed, the sheath is removed; specifically, the sheath after hot isostatic pressing is removed by machining, and after the sheath is removed, the overall size of the product and the thickness of the coating layer are measured, and the thickness of the coating layer is detected by an ultrasonic thickness gauge, and the blank is fine-machined. The fine-machining generally includes turning, grinding and other processes to achieve the size, shape and position tolerance and surface roughness required by the drawing, and finally obtain the finished product.

[0048] The preparation method of the tungsten-based heavy alloy surface-coated stainless steel component of the present invention has the advantages of simple process, batch production and low cost.

[0049] The present invention also discloses a tungsten-based heavy alloy surface-coated stainless steel component, which is prepared by applying the above-mentioned method for preparing a tungsten-based heavy alloy surface-coated stainless steel component. The tungsten-based heavy alloy surface-coated stainless steel component is processed by contacting the surfaces of a tungsten alloy block and an austenitic stainless steel block, placing in a sheath, assembling, powdering, sealing and welding the sheath, degassing, hot isostatic pressing, removing the sheath processing design dimensions, measuring the coating layer thickness, measuring the mechanical properties of the furnace parts, and then the coated component is prepared.

[0050] The invention also discloses an application of a tungsten-based heavy alloy surface-coated stainless steel component, and the tungsten-based heavy alloy surface-coated stainless steel component is used for a nuclear power main pump flywheel balance block.

[0051] The present invention uses 95WNiFe and 97WNiFe as tungsten-based heavy alloys for testing, and the properties of 95WNiFe and 97WNiFe are shown in Table 1; 304L stainless steel plate and 304L powder are used as austenitic stainless steel for testing, and the properties of 304L stainless steel plate and 304L powder are shown in Table 2.

[0052] Table 1: Composition and physical properties of 95WNiFe and 97WniFe

[0053]

[0054] Table 2: Composition and physical properties of 304L stainless steel plate and 304L powder

[0055]

[0056]

[0057] Example 1

[0058] A method for preparing a tungsten-based heavy alloy surface-coated stainless steel component: nickel is plated on a 97WNiFe alloy block to obtain a 97WNiFe alloy block with a nickel layer, and a 304L plate and a 304L pipe are directly wrapped around the nickel-plated 97WNiFe alloy block to obtain a sheath component, at which time, it is not necessary to use a sheath made of other materials, and only the 304L plate and the pipe are retained as the sheath; the assembled sheath component is hot isostatically pressed, and the hot isostatic pressing process is as follows: the temperature is 1200±10℃, the pressure is 140±10MPa, the heat and pressure are maintained for 1.0h, the temperature is lowered along with the furnace, and the temperature is lower than 300℃ when the furnace is taken out, and after the hot isostatic pressing process is completed, the hot isostatic pressing process is directly machined to the following conditions: Figure 2 The shape shown includes a tungsten or tungsten alloy substrate 11 and austenitic stainless steel 10; the thickness of the coated austenitic stainless steel can be processed to > 0.3 mm according to demand, and the mechanical properties and electron microscope samples are obtained by furnace samples.

[0059] The assembly diagram of this embodiment is shown in FIG. Figure 3 As shown, it includes a tungsten alloy block 5, the outer side of the tungsten alloy block 5 is coated with a sleeve 3, the two ends of the sleeve 3 are respectively provided with a sleeve upper end cover 1 and a sleeve lower end cover 6, a 304L plate 2 is provided between the tungsten alloy block 5 and the sleeve upper end cover 1, and the sleeve 3 is also provided with a degassing hole 4. After the assembly and processing of this embodiment is completed, the obtained product is as shown Figure 2 shown.

[0060] The measured mechanical properties are: interface tensile strength is 201MPa, SEM electron microscope image is as follows Figure 4 As shown, from Figure 4 It can be seen that the connection between tungsten-based heavy alloy and austenitic stainless steel is very good, with an obvious diffusion layer.

[0061] In this embodiment, both are solid, with little deformation during hot isostatic pressing and easy positioning. The 97WNiFe alloy block is not easy to move or dislocate, and is easy to position during machining. The final coating layer thickness has high accuracy, but this embodiment is only suitable for processing parts with simple shapes and structures.

[0062] Example 2

[0063] A method for preparing a tungsten-based heavy alloy surface-coated stainless steel component: nickel is plated on a 97WNiFe alloy block to obtain a 97WNiFe alloy block with a nickel layer, a sheath is set on the outer periphery of the 97WNiFe alloy block with a nickel layer, 304L powder is installed around the nickel-plated 97WNiFe alloy block through a sheath (A3 steel, 2.5 mm thick) to obtain an assembled sheath component; the assembled sheath component is hot isostatically pressed, and the hot isostatic pressing process: temperature 1200±10°C, pressure 140±10MPa, heat and pressure holding for 1.0h. The component is cooled as the furnace is cooled, and is taken out of the furnace when the temperature is below 300°C. After the hot isostatic pressing process, the sheath is directly machined to remove the sheath, and the 97WNiFe is used as the center as the reference, and the component is processed to the following: Figure 2 The shape shown, the thickness of the coated austenitic stainless steel can be processed to > 0.3mm according to the requirements, and the mechanical properties and electron microscope samples are obtained by furnace samples;

[0064] The assembly diagram of this embodiment is as follows Figure 5 As shown, the package 3 includes a bag 3, the inside of which is filled with 304L powder 7, and the bag 3 is also provided with a degassing hole 4. After the assembly and processing of this embodiment is completed, the obtained product is as follows Figure 2 shown.

[0065] The measured mechanical properties are: interface tensile strength is 230MPa, SEM electron microscope image is as follows Figure 6 As shown, from Figure 6 It can be seen that the connection between tungsten-based heavy alloy and austenitic stainless steel is very good, with an obvious diffusion layer.

[0066] This embodiment can process parts with complex shapes and structures, and has low requirements for the surface roughness of the 97WNiFe alloy block. Due to the lack of a positioning device, the 97WNiFe alloy block can easily move away from the center position during the powder loading, vibration, and transportation process, resulting in uneven coating thickness on the final processed parts.

[0067] Example 3

[0068] A method for preparing a tungsten-based heavy alloy surface-coated stainless steel component comprises the following steps: nickel is plated on a 97WNiFe alloy block to obtain a 97WNiFe alloy block having a nickel layer; a processed 304L plate is placed at a required position, and the 97WNiFe alloy block having a nickel layer is positioned according to the position of the 304L plate, the 304L plate and the 97WNiFe alloy block are assembled in a sheath (A3 steel, 2.5 mm thick), and then 304L powder is filled into the gap between the sheath, the 304L plate and the 97WNiFe alloy block to obtain an assembled sheath component; the assembled sheath component is hot isostatically pressed, and the hot isostatic pressing process comprises the following steps: temperature of 1200±10°C, pressure of 140±10MPa, heat and pressure holding for 1.0h, cooling with the furnace, and taking the component out of the furnace when the temperature is lower than 300°C; after the hot isostatic pressing process is completed, the sheath is directly removed by machining, and the 97WNiFe is processed to the center as a reference. Figure 2 The shape shown, the thickness of the coated austenitic stainless steel can be processed to > 0.3mm according to the requirements, and the mechanical properties and electron microscope samples are obtained by furnace samples;

[0069] The assembly diagram of this embodiment is shown in FIG. Figure 7 As shown, it includes a tungsten alloy column 9, the outer side of the tungsten alloy column 9 is covered with a sleeve 3, a 304L plate 2 is arranged between the sleeve 3 and the tungsten alloy column 9, and the sleeve 3 is also provided with a degassing hole 4 and a ceramic positioning pin 8. After the assembly and processing of this embodiment is completed, the obtained product is as follows Figure 2 shown.

[0070] The measured mechanical properties are: the interface tensile properties of 304L powder + 97WNiFe block and 304L plate and 97WNiFe are all greater than 210MPa, as shown in the SEM electron microscope image. Figure 8 As shown, from Figure 8 It can be seen that the connection between tungsten-based heavy alloy and austenitic stainless steel is very good, with an obvious diffusion layer.

[0071] This embodiment can not only process complex parts, but also position nickel-plated 97WNiFe alloy blocks, and will not deviate from the position during powder loading, vibration, and transportation; however, it is necessary to place positioning pins on the 304L positioning plate to easily determine the positioning points during processing.

[0072] Comparative Example

[0073] In current industrial applications, one method is to assemble the tungsten alloy balance block with a stainless steel shell, and then connect the stainless steel shell with argon arc welding, and there is no metallurgical bonding between the tungsten alloy and the stainless steel; another method is to use brazing to achieve the connection between the tungsten alloy and the stainless steel, using copper-based brazing filler metal, nickel-based brazing filler metal, copper-based brazing filler metal, etc. to achieve diffusion connection between the liquid brazing filler metal and the workpiece, but the bonding strength is relatively low, only 50-80MPa; the third method is to use hot isostatic pressing, and the connection temperature must reach 70% of the melting point of the lower material, while considering the melting point of the adhesion transition layer material. The adhesion transition layer cannot have a liquid phase during hot isostatic pressing, so the present invention selects a temperature range of 1000-1350°C as the hot isostatic pressing diffusion connection process. When the temperature is lower than 1000°C, the interface bonding force is very weak, or even not connected; when the temperature is higher than 1400°C, there is a risk of liquid phase, resulting in sheath leakage.

[0074] In summary, the preparation method of the present invention is simple and convenient, and can realize the one-time connection of corrosion-resistant materials around tungsten-based high-melting-point materials, and the prepared components have good interface bonding strength, no stress concentration, and a dense structure.

[0075] The embodiments described above are merely descriptions of preferred implementations of the present invention and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary engineering and technical personnel in the field should all fall within the protection scope of the claims of the present invention.

Claims

1. A method for preparing a tungsten-based heavy alloy surface-coated stainless steel component, characterized in that: The following steps are involved: Adding a transition layer on the surface of the tungsten-nickel-iron alloy; Assembling the tungsten-nickel-iron alloy with a transition layer and austenitic stainless steel to obtain a sheath component; Degassing and hot isostatic pressing of the package assembly; After hot isostatic pressing is completed, the jacket is removed.

2. The method for preparing a tungsten-based heavy alloy surface-coated stainless steel component according to claim 1, characterized in that: The transition layer is a Ni transition layer, and the thickness of the transition layer is 10 μm-30 μm.

3. The method for preparing a tungsten-based heavy alloy surface-coated stainless steel component according to claim 1, characterized in that: The transition layer is made by electroplating, spraying or vapor deposition.

4. The method for preparing a tungsten-based heavy alloy surface-coated stainless steel component according to claim 1, characterized in that: The method of assembling the tungsten-nickel-iron alloy with the transition layer and the austenitic stainless steel to obtain the sheath component includes: assembling the austenitic stainless steel and the tungsten-nickel-iron alloy by solid-solid diffusion connection.

5. The method for preparing a tungsten-based heavy alloy surface-coated stainless steel component according to claim 1, characterized in that: The method of assembling the tungsten-nickel-iron alloy with a transition layer and austenitic stainless steel to obtain a sheath assembly includes: filling austenitic stainless steel powder in the gap between the sheath and the tungsten-nickel-iron alloy component, and assembling the austenitic stainless steel and the tungsten-nickel-iron alloy by powder metallurgy.

6. The method for preparing a tungsten-based heavy alloy surface-coated stainless steel component according to claim 1, characterized in that: The method of assembling the tungsten-nickel-iron alloy with a transition layer and austenitic stainless steel to obtain a sheath assembly includes: using solid austenitic stainless steel to fix the position, filling the gaps between the austenitic stainless steel, the tungsten-nickel-iron alloy parts and the sheath with connecting powder, and assembling the austenitic stainless steel and the tungsten-nickel-iron alloy by combining diffusion bonding and powder metallurgy.

7. The method for preparing a tungsten-based heavy alloy surface-coated stainless steel component according to claim 1, characterized in that: The degassing process includes: keeping the temperature at 350°C-550°C for 1h-6h, and the vacuum degree is ≤2×10 -3 Pa.

8. The method for preparing a tungsten-based heavy alloy surface-coated stainless steel component according to claim 1, characterized in that: The hot isostatic pressing comprises: maintaining the temperature at 1000° C.-1350° C., the pressure at 100 MPa-150 MPa, and maintaining the temperature and pressure for 0.5 h-4 h.

9. The method for preparing a tungsten-based heavy alloy surface-coated stainless steel component according to claim 1, characterized in that: The removing of the sheath comprises: removing the sheath by machining.

10. A tungsten-based heavy alloy surface-coated stainless steel component, characterized in that: The material is prepared by the method for preparing a tungsten-based heavy alloy surface-coated stainless steel component as described in any one of claims 1 to 9.

11. An application of a tungsten-based heavy alloy surface coated stainless steel component according to claim 10, characterized in that: The tungsten-based heavy alloy surface-coated stainless steel component in claim 10 is used for the flywheel balance block of the nuclear power main pump.

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