A large-size tungsten alloy product and its preparation method

Abstract

The present invention provides a large-size tungsten alloy product and a preparation method thereof, the preparation method comprising: splicing cold isostatically pressed tungsten alloy blanks according to the size of the target product, the flatness of the spliced ​​splicing surface is less than 0.1 mm; heat treating and hot isostatically pressing the spliced ​​tungsten alloy blanks in sequence to obtain the tungsten alloy product. The preparation method provided by the present invention can prepare high-quality large-size tungsten alloy products with a length of more than 1000 mm, solves the problem that the size of the product is limited by the size of the equipment during the cold isostatic pressing production process, and also avoids the problem that large-size products are prone to breakage during the one-time cold isostatic pressing process, reducing the scrapping of blanks, and at the same time, the blanks that have been broken during the cold isostatic pressing process can also be used to effectively recycle the broken ingots.

Description

Technical Field

[0001] The invention belongs to the technical field of powder metallurgy, and in particular relates to a large-size tungsten alloy product and a preparation method thereof. Background Art

[0002] Tungsten alloy has many outstanding physical and chemical properties such as high melting point, high hardness, high wear resistance, excellent high temperature strength, thermal conductivity, electrical conductivity and corrosion resistance. It is widely used in many fields such as machinery, electronics, chemical industry, atomic energy, military, aviation, aerospace, etc.

[0003] At present, some large-sized tungsten alloy products are usually obtained by hot isostatic pressing and then heat treatment. For large-sized tungsten alloy parts, their size has high requirements on equipment, and large-scale cold isostatic pressing equipment is required. The product size is restricted by the equipment; on the other hand, the strength of tungsten alloy powder after cold isostatic pressing is not high, and directly producing large-sized products is prone to breakage and the product is scrapped.

[0004] CN109047781A discloses a method for preparing large-size tungsten products, using reduced tungsten powder as raw material, firstly using airflow milling, then spray granulation, forming tungsten powder agglomerates, and then using cold isostatic pressing and sintering processes to obtain thick tungsten slabs. This method pre-treats the raw tungsten powder to improve the sintering activity of the powder, thereby promoting the densification of the product, which affects the purity of the tungsten product to a certain extent, and the process is complicated.

[0005] CN108149102A discloses a method for preparing a large-sized high-performance tungsten alloy product, wherein tungsten alloy powder is uniformly mixed and pressed into a small-sized blank by cold isostatic pressing, sintered and densified, and then the workpieces are spliced, spliced, sintered and heat treated. This method requires multiple sintering and heat treatments, with many steps, and the small-sized blanks are sintered at multiple temperatures before splicing, and it is difficult to use the broken ingots after cold isostatic pressing. Summary of the invention

[0006] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a large-sized tungsten alloy product and a preparation method thereof, which can solve the problem of equipment constraints in the production process of large-sized tungsten alloy products and can also effectively solve the problem of effective utilization of broken tungsten alloy products.

[0007] To achieve this object, the present invention adopts the following technical solutions:

[0008] In a first aspect, the present invention provides a method for preparing a large-sized tungsten alloy product, the preparation method comprising the following steps:

[0009] (1) splicing the cold isostatically pressed tungsten alloy blanks according to the size of the target product, wherein the flatness of the spliced ​​surface is less than 0.1 mm;

[0010] (2) The spliced ​​tungsten alloy blanks are subjected to heat treatment and hot isostatic pressing in sequence to obtain tungsten alloy products.

[0011] The preparation method provided by the present invention can decompose the size of a target product with a larger size specification into several small sizes. First, tungsten alloy powder is used to prepare the small-sized tungsten alloy blanks by cold isostatic pressing, and then the small-sized tungsten alloy blanks are spliced ​​to ensure that the flatness of the spliced ​​splicing surface is less than 0.1mm. The specific heat treatment and hot isostatic pressing process of the present invention are used for processing to obtain a large-sized tungsten alloy product, which solves the problem that the size of the product is limited by the size of the equipment during the cold isostatic pressing production process, and also avoids the problem that large-sized products are prone to breakage during a one-time cold isostatic pressing process, thereby reducing the scrapping of blanks. At the same time, for the blanks that have been broken during the cold isostatic pressing process, the method provided by the present invention can also be used for splicing and processing to prepare qualified tungsten alloy products, and the broken ingots can be effectively recycled.

[0012] In the present invention, the large size range is: length is 1000-1700mm, width is 100-150mm, and height is 100-150mm.

[0013] The length of the large size is 1000-1700 mm, for example, it can be 1000 mm, 1100 mm, 1200 mm, 1300 mm, 1400 mm, 1500 mm, 1600 mm or 1700 mm, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0014] The width of the large size is 100-150 mm, for example, it can be 100 mm, 110 mm, 120 mm, 130 mm, 140 mm or 150 mm, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0015] The height of the large size is 100-150 mm, for example, it can be 100 mm, 110 mm, 120 mm, 130 mm, 140 mm or 150 mm, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0016] In the present invention, the flatness of the spliced ​​surface is less than 0.1 mm, for example, it can be 0.001 mm, 0.005 mm, 0.01 mm, 0.03 mm, 0.05 mm, 0.08 mm or 0.099 mm, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0017] The processing of the joint surface can adopt conventional processing methods in the art to ensure that the flatness is less than 0.1 mm, and the present invention does not make any specific limitation.

[0018] Preferably, the composition of the tungsten alloy includes: 5-15wt% titanium, and the balance tungsten.

[0019] The titanium content of the tungsten alloy is 5-15wt%, for example, it can be 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, 10wt%, 11wt%, 12wt%, 13wt%, 14wt% or 15wt%, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0020] Preferably, the heating rate of the heat treatment in step (2) is 4-6°C / min, for example, 4°C / min, 4.5°C / min, 5°C / min, 5.5°C / min or 6°C / min, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0021] Preferably, the temperature of the heat treatment in step (2) is 800-900°C, for example, it can be 800°C, 820°C, 840°C, 850°C, 860°C, 880°C or 900°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0022] Preferably, the heat treatment time in step (2) is 0.8-1.2 h, for example, 0.8 h, 0.9 h, 1.0 h, 1.1 h or 1.2 h, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0023] Preferably, the heating rate of the hot isostatic pressing in step (2) is 2-4°C / min, for example, it can be 2°C / min, 2.5°C / min, 3°C / min, 3.5°C / min or 4°C / min, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0024] Preferably, the temperature of the hot isostatic pressing in step (2) is 1000-1100°C, for example, it can be 1000°C, 1020°C, 1040°C, 1050°C, 1060°C, 1080°C or 1100°C, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0025] Preferably, the pressure of the hot isostatic pressing in step (2) is 160-200 MPa, for example, 160 MPa, 170 MPa, 180 MPa, 190 MPa or 200 MPa, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0026] Preferably, the hot isostatic pressing time in step (2) is 5-8 hours, for example, 5 hours, 6 hours, 7 hours or 8 hours, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0027] Preferably, during the hot isostatic pressing process in step (2), heating and pressure increase are started simultaneously, and the target temperature and pressure are reached at the same time.

[0028] Preferably, the cold isostatic pressing process in step (1) comprises: sequentially pressurizing the tungsten alloy powder to a first pressure, a second pressure and a third pressure for pressing.

[0029] Preferably, the pressure rise time of the first pressure is 18-22 min, for example, it can be 18 min, 19 min, 20 min, 21 min or 22 min, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0030] Preferably, the first pressure is 80-90 MPa, for example, 80 MPa, 82 MPa, 84 MPa, 85 MPa, 86 MPa, 88 MPa or 90 MPa, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0031] Preferably, the holding time of the first pressure is 1-3 min, for example, 1 min, 1.5 min, 2 min, 2.5 min or 3 min, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0032] Preferably, the pressure rise time of the second pressure is 14-16 min, for example, it can be 14 min, 14.5 min, 15 min, 15.5 min or 16 min, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0033] Preferably, the second pressure is 150-180 MPa, for example, 150 MPa, 160 MPa, 170 MPa or 180 MPa, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0034] Preferably, the holding time of the second pressure is 5-8 minutes, for example, 5 minutes, 6 minutes, 7 minutes or 8 minutes, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0035] Preferably, the pressure increase time of the third pressure is 18-22 minutes, for example, it can be 18 minutes, 19 minutes, 20 minutes, 21 minutes or 22 minutes, but it is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0036] Preferably, the third pressure is 180-220 MPa, for example, 180 MPa, 190 MPa, 200 MPa, 210 MPa or 220 MPa, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0037] Preferably, the holding time of the third pressure is 6-10 min, for example, 6 min, 7 min, 8 min, 9 min or 10 min, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0038] As a preferred technical solution of the preparation method provided by the present invention, the preparation method comprises the following steps:

[0039] (1) splicing the cold isostatically pressed tungsten alloy blanks according to the size of the target product, wherein the flatness of the spliced ​​surface is less than 0.1 mm;

[0040] The tungsten alloy blank subjected to cold isostatic pressing includes: a tungsten alloy product that is broken after cold isostatic pressing, or a tungsten alloy product of small size prepared by cold isostatic pressing by decomposing the size of the target product into small sizes;

[0041] The preparation process of the cold isostatic pressing method includes: firstly increasing the pressure of the tungsten alloy powder to 80-90MPa in 18-22 minutes, maintaining the pressure for 1-3 minutes, then increasing the pressure to 150-180MPa in 14-16 minutes, maintaining the pressure for 5-8 minutes, and finally increasing the pressure to 180-220MPa in 18-22 minutes, maintaining the pressure for 6-10 minutes;

[0042] (2) The spliced ​​tungsten alloy blanks are placed in a package, placed in a sintering device, filled with argon gas and pressurized to no more than 10 MPa, and first subjected to heat treatment, wherein the heat treatment process is: raising the temperature to 800-900°C at a rate of 4-6°C / min and keeping the temperature for 0.8-1.2 h; then subjected to hot isostatic pressing, wherein the hot isostatic pressing process is: raising the temperature to 1000-1100°C at a rate of 2-4°C / min, and at the same time, performing air pressurization, and when the temperature reaches the target temperature, the pressure is increased to 160-200 MPa, and then the temperature is kept and pressurized for 5-8 h. After the heat preservation and pressurization are completed, the large-sized tungsten alloy product is obtained.

[0043] In a second aspect, the present invention provides a large-sized tungsten alloy product, wherein the large-sized tungsten alloy product is prepared by the preparation method described in the first aspect.

[0044] Compared with the prior art, the present invention has the following beneficial effects:

[0045] The preparation method provided by the present invention can prepare high-quality large-size tungsten alloy products with a length of more than 1000 mm, which solves the problem that the size of the product is limited by the size of the equipment during the cold isostatic pressing production process, and also avoids the problem that large-size products are prone to breakage during a one-time cold isostatic pressing process, thereby reducing the scrapping of billets. At the same time, billets that have been broken during the cold isostatic pressing process can also be used to effectively recycle the broken ingots. DETAILED DESCRIPTION

[0046] The technical solution of the present invention is further illustrated below through specific implementation methods.

[0047] In order to clearly illustrate the technical solution of the present invention, in a specific implementation manner, the composition of the tungsten alloy used includes: 10wt% titanium and the balance tungsten.

[0048] Example 1

[0049] This embodiment provides a method for preparing a large-sized tungsten alloy product.

[0050] In this embodiment, the dimensions of the large-sized tungsten alloy product are: length 1500 mm, width 120 mm, and height 120 mm.

[0051] The preparation method comprises the following steps:

[0052] (1) The size of the large-sized tungsten alloy product to be prepared is decomposed into three small sizes of 500 mm in length, 120 mm in width and 120 mm in height; the tungsten alloy powder is cold isostatically pressed according to the small sizes, and the cold isostatic pressing process is: firstly, the pressure is increased to 85 MPa in 20 minutes, and the pressure is maintained for 2 minutes, then the pressure is increased to 160 MPa in 15 minutes, and the pressure is maintained for 6 minutes, and finally, the pressure is increased to 200 MPa in 20 minutes, and the pressure is maintained for 8 minutes, so as to obtain three tungsten alloy blanks of the small sizes respectively;

[0053] (2) processing the joint surface of the tungsten alloy blank obtained in step (1) to obtain a flatness of 0.08 mm, and splicing the tungsten alloy blank according to the size of the tungsten alloy product to fit the joint surface;

[0054] (3) The spliced ​​tungsten alloy blanks are placed in a sleeve, and the sleeve and the product are tightly fitted to prevent the blanks from shifting. The blanks are then placed in a furnace. After the product is placed in the furnace, argon gas is filled and the pressure is increased by no more than 10 MPa. The temperature is raised to 850°C at a rate of 5°C / min and kept warm for 1 hour. No additional air pressure is required. The pressure in the equipment is naturally increased. After the 850°C insulation is completed, the temperature is increased to 1050°C at a rate of 3°C / min, and air pressure is started at the same time. When the temperature reaches 1050°C, the pressure is also increased to 180 MPa. Thereafter, insulation and pressure maintenance are started for 6 hours. After the insulation and pressure maintenance are completed, the sintering is terminated, the pressure is reduced, and the temperature is lowered to obtain the large-sized tungsten alloy product.

[0055] Example 2

[0056] This embodiment provides a method for preparing a large-sized tungsten alloy product.

[0057] In this embodiment, the dimensions of the large-sized tungsten alloy product are: length 1700 mm, width 150 mm, and height 150 mm.

[0058] The preparation method comprises the following steps:

[0059] (1) The size of the large-sized tungsten alloy product to be prepared is decomposed into three small sizes with lengths of 500 mm, 500 mm and 700 mm, widths of 150 mm and heights of 150 mm; the tungsten alloy powder is cold isostatically pressed according to the small sizes, and the cold isostatic pressing process is: first, the pressure is increased to 80 MPa in 18 minutes, and the pressure is maintained for 3 minutes, then the pressure is increased to 150 MPa in 14 minutes, and the pressure is maintained for 8 minutes, and finally the pressure is increased to 180 MPa in 18 minutes, and the pressure is maintained for 10 minutes, so as to obtain three small-sized tungsten alloy blanks respectively;

[0060] (2) processing the joint surfaces of the tungsten alloy blanks obtained in step (1) so that the flatness of the joint surfaces is 0.08 mm, and splicing the tungsten alloy blanks according to the size of the tungsten alloy product, and laminating the joint surfaces;

[0061] (3) The spliced ​​tungsten alloy blanks are loaded into a sleeve, and the sleeve and the product are tightly fitted to prevent the blanks from shifting. Then the blanks are placed in a furnace. After the product is placed in the furnace, argon gas is filled and the pressure is increased by no more than 10 MPa. The temperature is raised to 800°C at 4°C / min and kept warm for 1.2 hours. No additional air pressure is required. The pressure in the equipment is naturally increased. After the 800°C insulation is completed, the temperature is raised to 1000°C at 2°C / min, and air pressure is started at the same time. When the temperature reaches 1000°C, the pressure is also increased to 160 MPa. Thereafter, insulation and pressure maintenance are started for 8 hours. After the insulation and pressure maintenance are completed, the sintering is terminated, the pressure is reduced, and the temperature is lowered to obtain the large-sized tungsten alloy product.

[0062] Example 3

[0063] This embodiment provides a method for preparing a large-sized tungsten alloy product.

[0064] In this embodiment, the dimensions of the large-sized tungsten alloy product are: length 1700 mm, width 150 mm, and height 150 mm.

[0065] The preparation method comprises the following steps:

[0066] (1) The size of the large-sized tungsten alloy product to be prepared is decomposed into three small sizes with lengths of 500 mm, 500 mm and 700 mm, widths of 150 mm and heights of 150 mm; the tungsten alloy powder is cold isostatically pressed according to the small sizes, and the cold isostatic pressing process is: first, the pressure is increased to 90 MPa in 22 minutes, and the pressure is maintained for 1 minute, then the pressure is increased to 180 MPa in 16 minutes, and the pressure is maintained for 5 minutes, and finally the pressure is increased to 220 MPa in 22 minutes, and the pressure is maintained for 6 minutes, so as to obtain three small-sized tungsten alloy blanks respectively;

[0067] (2) processing the joint surfaces of the tungsten alloy blanks obtained in step (1) so that the flatness of the joint surfaces is 0.08 mm, and splicing the tungsten alloy blanks according to the size of the tungsten alloy product, and laminating the joint surfaces;

[0068] (3) The spliced ​​tungsten alloy blanks are placed in a sleeve, and the sleeve and the product are tightly fitted to prevent the blanks from shifting. Then the blanks are placed in a furnace. After the product is placed in the furnace, argon gas is filled and the pressure is increased by no more than 10 MPa. The temperature is raised to 900°C at 6°C / min and kept warm for 0.8 hours. No additional air pressure increase is required. The pressure in the equipment is naturally increased. After the 900°C insulation is completed, the temperature is raised to 1100°C at 4°C / min, and air pressure increase is started at the same time. When the temperature reaches 1100°C, the pressure is also increased to 200 MPa. Thereafter, insulation and pressure maintenance are started for 5 hours. After the insulation and pressure maintenance are completed, the sintering is terminated, the pressure is reduced, and the temperature is lowered to obtain the large-sized tungsten alloy product.

[0069] Example 4

[0070] This embodiment provides a method for preparing a large-sized tungsten alloy product. Compared with Embodiment 1, the pressure of the hot isostatic pressing in step (3) is 150 MPa, and the rest is the same as Embodiment 1.

[0071] Example 5

[0072] This embodiment provides a method for preparing a large-sized tungsten alloy product. Compared with Embodiment 1, the pressure of the hot isostatic pressing in step (3) is 220 MPa, and the rest is the same as Embodiment 1.

[0073] Example 6

[0074] This embodiment provides a method for preparing a large-sized tungsten alloy product. Compared with Embodiment 1, the temperature of hot isostatic pressing in step (3) is 900° C., and the rest is the same as Embodiment 1.

[0075] Example 7

[0076] This embodiment provides a method for preparing a large-sized tungsten alloy product. Compared with Embodiment 1, the temperature of hot isostatic pressing in step (3) is 1200° C., and the rest is the same as Embodiment 1.

[0077] Example 8

[0078] This embodiment provides a method for preparing a large-sized tungsten alloy product. Compared with Example 1, the cold isostatic pressing process in step (1) is to directly increase the pressure to 200 MPa in the same time, and the rest is the same as Example 1.

[0079] Comparative Example 1

[0080] This comparative example provides a method for preparing a large-sized tungsten alloy product. Compared with Example 1, no pressurization is performed in step (3), and the rest is the same as Example 1.

[0081] Comparative Example 2

[0082] This comparative example provides a method for preparing a large-sized tungsten alloy product. Compared with Example 1, step (3) does not perform a heat treatment at 850° C., and the rest is the same as Example 1.

[0083] Table 1

[0084]

[0085]

[0086] As can be seen from Table 1, the preparation method provided by the present invention can prepare large-sized tungsten alloy products, which are not limited by the size of the equipment, and have good density and performance. Compared with Example 1, in Examples 4-8, after adjusting the process parameters, the product quality is affected to a certain extent, and the product strength performance is slightly reduced. In Comparative Examples 1-2, the product performance is significantly reduced and it is difficult to meet the use requirements. It can be seen that the process steps of the present invention are crucial to the performance of tungsten products.

[0087] In summary, the preparation method provided by the present invention can prepare large-sized tungsten alloy products with a length of more than 1000 mm, which solves the problem that the size of the product is limited by the size of the equipment during the cold isostatic pressing production process, and also avoids the problem that large-sized products are prone to breakage during a one-time cold isostatic pressing process, thereby reducing the scrapping of billets. At the same time, billets that have been broken during the cold isostatic pressing process can also be used to effectively recycle the broken ingots.

[0088] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preparing a large-size tungsten alloy product, characterized in that: The preparation method comprises the following steps: (1) splicing the cold isostatically pressed tungsten alloy blanks according to the size of the target product, wherein the flatness of the spliced ​​surface is less than 0.1 mm; (2) The spliced ​​tungsten alloy blanks are subjected to heat treatment and hot isostatic pressing in sequence to obtain tungsten alloy products.

2. The preparation method according to claim 1, characterized in that: The heating rate of the heat treatment in step (2) is 4-6°C / min; Preferably, the temperature of the heat treatment in step (2) is 800-900°C.

3. The preparation method according to claim 1 or 2, characterized in that: The heat treatment time in step (2) is 0.8-1.2h.

4. The preparation method according to any one of claims 1 to 3, characterized in that The heating rate of the hot isostatic pressing in step (2) is 2-4°C / min; Preferably, the temperature of the hot isostatic pressing in step (2) is 1000-1100°C.

5. The preparation method according to any one of claims 1 to 4, characterized in that: The pressure of the hot isostatic pressing in step (2) is 160-200 MPa.

6. The preparation method according to any one of claims 1 to 5, characterized in that: The hot isostatic pressing time in step (2) is 5-8 hours.

7. The preparation method according to any one of claims 1 to 6, characterized in that: During the hot isostatic pressing process of step (2), heating and pressure increase are started simultaneously, and the target temperature and pressure are reached at the same time.

8. The preparation method according to any one of claims 1 to 7, characterized in that: The cold isostatic pressing process in step (1) comprises: pressing the tungsten alloy powder to a first pressure, a second pressure and a third pressure in sequence; Preferably, the first pressure rise time is 18-22 minutes; Preferably, the first pressure is 80-90 MPa; Preferably, the holding time of the first pressure is 1-3 minutes; Preferably, the second pressure rise time is 14-16 minutes; Preferably, the second pressure is 150-180 MPa; Preferably, the holding time of the second pressure is 5-8 minutes; Preferably, the third pressure boost time is 18-22 minutes; Preferably, the third pressure is 180-220 MPa; Preferably, the holding time of the third pressure is 6-10 minutes.

9. The preparation method according to any one of claims 1 to 8, characterized in that: The preparation method comprises the following steps: (1) splicing the cold isostatically pressed tungsten alloy blanks according to the size of the target product, wherein the flatness of the spliced ​​surface is less than 0.1 mm; The tungsten alloy blank subjected to cold isostatic pressing includes: a tungsten alloy product that is broken after cold isostatic pressing, or a tungsten alloy product of small size prepared by cold isostatic pressing by decomposing the size of the target product into small sizes; The preparation process of the cold isostatic pressing method includes: firstly increasing the pressure of the tungsten alloy powder to 80-90MPa in 18-22 minutes, maintaining the pressure for 1-3 minutes, then increasing the pressure to 150-180MPa in 14-16 minutes, maintaining the pressure for 5-8 minutes, and finally increasing the pressure to 180-220MPa in 18-22 minutes, maintaining the pressure for 6-10 minutes; (2) The spliced ​​tungsten alloy blanks are placed in a package, placed in a sintering device, filled with argon gas and pressurized to no more than 10 MPa, and first subjected to heat treatment, wherein the heat treatment process is: raising the temperature to 800-900°C at a rate of 4-6°C / min and keeping the temperature for 0.8-1.2 h; then subjected to hot isostatic pressing, wherein the hot isostatic pressing process is: raising the temperature to 1000-1100°C at a rate of 2-4°C / min, and at the same time, performing air pressurization, and when the temperature reaches the target temperature, the pressure is increased to 160-200 MPa, and then the temperature is kept and pressurized for 5-8 h. After the heat preservation and pressurization are completed, the large-sized tungsten alloy product is obtained.

10. A large-size tungsten alloy product, characterized in that: The large-size tungsten alloy product is prepared by the preparation method described in any one of claims 1-9.

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