A method for producing high toughness tungsten alloy fragments
Through composition optimization and process innovation, high-toughness tungsten alloy fragments were prepared using powder metallurgy, which solved the problems of performance damage caused by mechanical grinding and uneven sintering of large sizes, and achieved tungsten alloy fragments with high dimensional accuracy and high pressure crushing performance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-03-20
- Publication Date
- 2026-05-29
AI Technical Summary
In the preparation of tungsten alloy fragments, existing technologies suffer from performance damage due to mechanical grinding, and uneven sintering shrinkage of large fragments affects performance uniformity, making it difficult to simultaneously guarantee high dimensional accuracy and high pressure crushing performance.
High-toughness tungsten alloy fragments were prepared by using a powder metallurgy method with optimized composition, combined with specific mold design and differentiated sintering process, avoiding mechanical grinding, and through activation treatment and vacuum heat treatment.
Tungsten alloy fragments with high dimensional accuracy and high crushing performance were prepared, with a crushing deformation of ≥50% and no cracking, achieving a good balance between strength and toughness, and good process adaptability to different sizes.
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Figure CN122099334A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of powder metallurgy technology, specifically to a method for preparing high-toughness tungsten alloy fragments. Background Technology
[0002] Due to the high density of tungsten, tungsten alloy fragments play an important role in key applications in related fields. As damage fragments, they can produce significant functional effects under high-speed driving, and are characterized by high material kinetic energy and good damage effect.
[0003] Currently, the industry commonly uses mechanical grinding to obtain the final shape and size of tungsten alloy spherical fragments. However, this machining process is a subtractive manufacturing process, which introduces damage such as microcracks on the surface and subsurface of the fragments, significantly deteriorating their mechanical properties. Tests show that the crushing deformation of mechanically ground tungsten alloy spherical fragments of the same specifications typically does not exceed 45%, meaning that cracking occurs at 45% deformation, resulting in insufficient crushing performance. For square or other shaped fragments, although heavy grinding is not required, optimizing the manufacturing process to obtain fragments with excellent overall performance, especially high crushing performance, while ensuring high dimensional accuracy, remains a technical challenge in this field. Existing powder metallurgy processes, when manufacturing large-sized (e.g., ≥10mm) fragments, are prone to product deformation or incomplete alloying due to uneven sintering shrinkage, affecting performance uniformity.
[0004] Therefore, there is an urgent need in this field for a new preparation method that can fundamentally avoid performance damage caused by machining and directly produce tungsten alloy fragments with both high dimensional accuracy and high pressure crushing performance through process innovation throughout the entire process. Summary of the Invention
[0005] The purpose of this invention is to provide a method for preparing high-toughness tungsten alloy fragments to overcome the above-mentioned defects of the prior art. Through the synergistic design of composition and process, tungsten alloy fragments with high dimensional accuracy and high crushing performance can be directly prepared, avoiding the negative effects of mechanical grinding.
[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A method for preparing high-toughness tungsten alloy fragments includes the following steps: S1. Ingredient mixing: Using W powder, Ni powder, Fe powder, Co powder and Mn powder as raw materials, mix with alcohol and perform high-energy wet milling to produce a uniform mixed powder; S2. Granulation and pressing: The mixed powder is dried and granulated, and the granulated material is placed in a mold and pressed into a blank; wherein, when pressing spherical fragments, the mold has a central process ring; when pressing square fragments, a bidirectional pressing method is used. S3. Activation sintering: The compact is activated and sintered according to the compact size to obtain sintered preform fragments. For compacts with a size less than 10 mm, direct sintering is used, and for compacts with a size greater than or equal to 10 mm, two sintering processes are used. S4. Polishing heat treatment: Polish the sintered pre-formed fragments and perform vacuum heat treatment to obtain the high-toughness tungsten alloy fragments.
[0007] Further, in step S1, the raw material composition by weight percentage is: W 92~94%, Ni 4~6%, Fe 1~3%, Co 0.1~1.0%, and Mn 0.01~0.1%.
[0008] Further, in step S1, the amount of alcohol added is 200~500mL / kg of powder, and the high-energy wet milling time is 24~48 hours.
[0009] Furthermore, in step S2, the particle size range of the granulated material is 40~100 mesh, and the proportion of material with a particle size of 60~80 mesh is not less than 50%.
[0010] Furthermore, in step S2, the width of the process ring of the spherical fragment is 1 / 8 to 1 / 4 of its compact height.
[0011] Furthermore, in step S2, the pressure used to compress the square fragment is 0.5 to 5 tons, and the pressure holding time is 2 to 10 seconds.
[0012] Furthermore, in step S3, the activation treatment temperature is 500~800℃, and the activation time is 24~48 hours.
[0013] Further, in step S3: The direct sintering temperature is 1515~1555℃, and the boat pushing speed is 8~15mm / min; The two sintering processes include: a first sintering temperature of 1430~1470℃ and a boat pushing speed of 10~20 mm / min; and a second sintering temperature of 1525~1565℃ and a boat pushing speed of 8~12 mm / min.
[0014] Further, in step S4: The polishing frequency is 180~250Hz, and the polishing time is 1~3 hours; The vacuum heat treatment temperature is 1150~1350℃, the holding time is 2~5 hours, and the vacuum degree is lower than... Pa.
[0015] Another object of the present invention is to provide a high-toughness tungsten alloy fragment, prepared by the aforementioned method for preparing a high-toughness tungsten alloy fragment, wherein the fragment has a hardness of 24~29HRC, a crush deformation of ≥50% and does not crack; its size range is 1~20 mm, and the dimensional tolerances meet the following requirements: When the fragments are square: size 1~6mm, tolerance ±0.05mm; size 6~10mm, tolerance ±0.08mm; size 10~15mm, tolerance ±0.15mm; size 15~20mm, tolerance ±0.25mm; When the fragments are spherical: size 1~5mm, tolerance is ±0.05mm; size 5~10mm, tolerance is ±0.15mm; size 10~15mm, tolerance is ±0.25mm; size 15~20mm, tolerance is ±0.35mm.
[0016] Compared with the prior art, the present invention has the following significant advantages: 1. High toughness: The tungsten alloy fragments prepared by this invention exhibit excellent crushing performance, with crushing deformation ≥50% and no cracking, far exceeding that of mechanically ground tungsten alloy spherical pre-formed fragments of the same specifications (crushing deformation ≤45%). This is attributed to the complete avoidance of mechanical grinding damage and the dense and tough microstructure obtained through the synergistic effects of composition optimization, activation treatment, controlled sintering, and vacuum heat treatment.
[0017] 2. High dimensional accuracy: Through optimized mold design (spherical pressing process ring belt, square pressing bidirectional pressure) and sintering process that is precisely matched with dimensions, sintering deformation is effectively controlled, resulting in high product dimensional accuracy.
[0018] 3. Balanced performance: Through strict control of composition (W, Ni, Fe, Co, Mn synergistic) and process control, the fragments achieve high hardness (24-29 HRC) while also possessing high crushing performance, thus achieving a good balance between strength and toughness.
[0019] 4. Good process adaptability: Differentiated sintering processes are designed for fragments of different sizes. In particular, a two-stage sintering method is used for large fragments (≥10mm), which solves the problem of sintering deformation and alloying of large-size powder metallurgy products, and ensures the stability of product performance. Attached Figure Description
[0020] Figure 1 This is a flowchart of the method of the present invention. Detailed Implementation
[0021] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.
[0022] This invention provides a method for preparing high-toughness tungsten alloy fragments. Figure 1 The core of this method lies in the synergistic effect of specific component design, innovative mold structure and pressing method, and differentiated sintering process precisely matched with product dimensions. This approach significantly improves the crushing performance of fragments while ensuring high dimensional accuracy. The following will first outline the process principles and optimal parameter ranges for each step of the method, and then provide detailed explanations and verifications through multiple embodiments.
[0023] S1. Ingredient Mixing: Using W powder, Ni powder, Fe powder, Co powder, and Mn powder as raw materials, mix with alcohol and perform high-energy wet milling to produce a uniform mixed powder. Based on the inventor's in-depth research, strictly controlling the tungsten content at 92-94% can effectively balance strength and toughness; nickel and iron, as binder phases, have their contents optimized within a specific range to help densification and improve mechanical properties; the addition of cobalt and manganese can suppress the formation of brittle phases and promote sintering. To achieve the above synergistic effects, preferably, the composition of the raw materials, by weight percentage, is: W 92-94%, Ni 4-6%, Fe 1-3%, Co 0.1-1.0%, and Mn 0.01-0.1%. The amount of alcohol added is 200-500 mL / kg of powder, and the high-energy wet milling time is 24-48 hours. During this process, alcohol acts as a process control agent, which can wet the powder surface, reduce van der Waals forces between particles, and avoid agglomeration, thereby ensuring the uniformity of particle size and composition of the material after ball milling.
[0024] S2. Granulation and Pressing: The mixed powder is dried and granulated, and the granulated material is placed in a mold and pressed into a blank. When pressing spherical fragments, the mold has a central process ring; when pressing square fragments, a bidirectional pressing method is used. The particle size range of the granulated material is 40-100 mesh, with 60-80 mesh material accounting for no less than 50%. The width of the process ring of the spherical fragment is 1 / 8 to 1 / 4 of the height of the pressed blank. The middle ring of the process ring serves as a transition zone to avoid a "saddle-shaped" distribution of "high density at the edges and low density at the center" in the tungsten alloy spherical blank. This reduces the pressure gradient between the edge and the center and increases the strength of the pressed blank, preventing cracking. If the ring width is too small, the pressed blank is prone to cracking from the center; if the ring width is too large, it is not conducive to the size control of the pre-made fragments. The pressing pressure for the square fragments is 0.5-5 tons, and the holding time is 2-10 seconds.
[0025] S3. Activation Sintering: The pressed compact is activated and sintered according to its size to obtain sintered pre-fragments. For compacts smaller than 10 mm, direct sintering is used; for compacts 10 mm or larger, two sintering processes are performed. The activation temperature is 500–800 °C, and the activation time is 24–48 hours. Activation of the pre-fragmented compact provides an ideal precursor for sintering, resulting in a porous structure that facilitates gas escape and densification during sintering, giving the compact a certain strength. The sintering is carried out in a pusher-type high-temperature molybdenum wire sintering furnace. The pusher speed is a key parameter controlling the sintering process, directly determining the rate at which the compact passes through different temperature zones within the furnace, thus affecting the densification process and the final grain structure. For compacts with dimensions less than 10 mm, direct sintering (sintering temperature 1515~1555℃, boat pushing speed 8~15 mm / min) can effectively control dimensional accuracy and performance. For compacts with dimensions greater than or equal to 10 mm, in order to overcome the problem of easy deformation during direct sintering, a two-stage sintering method is adopted (first sintering temperature 1430~1470℃, boat pushing speed 10~20 mm / min; second sintering temperature 1525~1565℃, boat pushing speed 8~12 mm / min). Initial shrinkage and shaping are achieved through a first rapid sintering, and then complete alloying is achieved through a second sintering.
[0026] S4. Polishing Heat Treatment: The sintered pre-formed fragments are polished and then subjected to vacuum heat treatment to obtain the high-toughness tungsten alloy fragments. The polishing frequency is 180~250Hz, and the polishing time is 1~3 hours. The vacuum heat treatment temperature is 1150~1350℃, the holding time is 2~5 hours, and the vacuum degree is lower than... Pa. Vacuum furnace annealing can avoid hydrogen embrittlement of tungsten alloy pre-fragments and improve the overall mechanical properties of the material.
[0027] The present invention will now be described in detail with reference to four embodiments. The process parameters and test results of these embodiments all fall within the protection scope defined by the foregoing claims, which fully verifies the feasibility and excellent effect of the present invention.
[0028] Example 1: Preparation of Φ4.0mm high-toughness tungsten alloy spherical fragments This embodiment aims to illustrate how to prepare small-sized (<10mm) spherical fragments.
[0029] 1. Ingredient Batching and Mixing: Accurately weigh the raw material powder, whose chemical composition by weight percentage (wt.%) is: W 93%, Ni 4.8%, Fe 1.8%, Co 0.38%, Mn 0.02%. Place the weighed powder in a mixer, add alcohol as a process control agent at a rate of 250 mL / kg of powder, and perform high-energy wet milling for 30 hours until a homogeneous slurry is obtained. This composition ensures sufficient binder phase and sintering activity, laying the foundation for high toughness. The wet milling parameters ensure uniform mixing of the powder.
[0030] 2. Granulation and Pressing: The wet-milled slurry is dried and then granulated using a granulator. The particle size distribution of the granulated material is controlled between 40 and 100 mesh, with 55% of the material being 60-80 mesh. The granulated material is then filled into a pre-designed mold and pressed into spherical compacts on a mechanical press. The compact height is 4.75 mm. The mold is designed with a central process ring belt, the width of which is 0.65 mm (approximately 1 / 7.3 of the compact height). The pressing pressure is 1 ton, and the holding pressure is 3 seconds.
[0031] The specific particle size distribution mentioned above ensures good material flowability and makes the pressing density more uniform. The use of a mold with a central process ring is one of the key features of this invention. This design effectively avoids a "saddle-shaped" density distribution in the spherical compact during pressing, thereby preventing the compact from cracking from the center and improving formability and compact strength.
[0032] 3. Activation Sintering: The pressed spherical compacts are transferred to an atmosphere furnace for activation treatment. The activation temperature is 500℃, and the activation time is 36 hours. After activation, the compacts are sent to a pusher-type high-temperature molybdenum wire sintering furnace for sintering. Since the fragment size (Φ4.0mm) in this embodiment is less than 10mm, the direct sintering method is adopted. Sintering is carried out under a hydrogen protective atmosphere, using 120-mesh alumina sand for burial. The sintering temperature is 1545℃, and the pusher speed is 8mm / min. The activation treatment provides an ideal porous precursor for sintering. For small fragments, the direct sintering method, combined with an appropriate pusher speed, can ensure complete alloying while precisely controlling the product size and avoiding excessive deformation.
[0033] 4. Polishing Heat Treatment: The sintered fragments are placed in a polishing machine and polished at a frequency of 200 Hz for 1.5 hours to remove the surface oxide layer and adhering substances, resulting in sintered fragments with a smooth surface. The polished fragments are then placed in a vacuum furnace for heat treatment. The heat treatment temperature is 1180℃, held for 4 hours, and the vacuum level is maintained at [missing value]. Below Pa. Polishing improves surface quality, and the final vacuum heat treatment is crucial. It not only eliminates internal stress in the material but also effectively avoids the "hydrogen embrittlement" phenomenon that may be caused by traditional hydrogen sintering, thereby comprehensively improving the toughness and overall mechanical properties of the material.
[0034] 5. Final Product Performance and Precision Verification: The obtained tungsten alloy spherical fragments were tested. Their hardness was 26.7 HRC, and they did not crack when the crush deformation reached 55.2%. Using precision measuring instruments, the fragment dimensions were sampled and measured, with an average diameter of 4.0 mm and a dimensional tolerance controlled within ±0.05 mm. This demonstrates the high-precision control capability of this invention for small-sized spherical fragments.
[0035] Example 2: Preparation of Φ11.5mm high-toughness tungsten alloy spherical fragments This embodiment aims to illustrate how to prepare large-sized (≥10mm) spherical fragments and demonstrate the application of the two-stage sintering method.
[0036] 1. Ingredient mixing: The raw material ratio (wt.%) is: W 92%, Ni 5.4%, Fe 2.0%, Co 0.52%, Mn 0.08%. The amount of alcohol added is 350mL / kg of powder, and high-energy wet milling is performed for 48 hours.
[0037] 2. Granulation and pressing: The particle size range of the granulated material is 40~100 mesh, with 60~80 mesh accounting for 63.2%. Spherical compacts are pressed, with a compact height of 13.68mm. The width of the process ring at the center of the die is 3.35mm (approximately 1 / 4.1 of the compact height), the pressing pressure is 5 tons, and the holding pressure is 6 seconds.
[0038] 3. Activation Sintering: Activation treatment was carried out at 800℃ for 26 hours. Since the fragment size (Φ11.5mm) was ≥10mm, a two-stage sintering method was adopted. The first sintering temperature was 1430℃, and the boat pushing speed was 10mm / min, achieving a compact shrinkage rate of 91.8%. The second sintering temperature was 1565℃, and the boat pushing speed was 12mm / min, ensuring complete alloying of the fragments. The protective atmosphere was hydrogen, and the burial medium was 180-mesh alumina sand.
[0039] For large-sized fragments, the core of this invention is the use of two sintering processes. The first rapid high-temperature sintering achieves initial densification and shaping, while the second sintering at a lower temperature and slower speed completes the final alloying, effectively solving the problem of easy deformation of large-sized blanks during single sintering.
[0040] 4. Polishing heat treatment: Polishing frequency 250 Hz, time 1.2 hours. Vacuum heat treatment temperature 1300℃, holding time 3 hours, vacuum degree < Pa.
[0041] 5. Final product performance and precision verification: The obtained spherical fragments have a hardness of 27.5 HRC and a crush deformation of 53.6%. Dimensionally, the average diameter is 11.5 mm, and the dimensional tolerance is controlled within ±0.25 mm.
[0042] Example 3: Preparation of 5mm cubic high-toughness tungsten alloy square fragments This embodiment aims to illustrate the preparation process of square fragments and demonstrate the effect of bidirectional pressure.
[0043] 1. Ingredient mixing: The raw material ratio (wt.%) is: W 94%, Ni 4.2%, Fe 1.35%, Co 0.4%, Mn 0.05%. The amount of alcohol added is 500mL / kg of powder, and high-energy wet milling is performed for 30 hours.
[0044] 2. Granulation and Pressing: After granulation, 61.8% of the material is 60-80 mesh. When pressing the square preform, a bidirectional pressing method is used, with a preform height of 5.93 mm, a pressing pressure of 1.2 tons, and a holding time of 5 seconds. The bidirectional pressing of the square fragments is a key design feature of this invention, significantly improving the uniformity of density distribution during pressing, thereby enhancing the formability of the preform and the dimensional accuracy of the final product.
[0045] 3. Activation sintering: Activation conditions are 600℃ for 40 hours. For fragments <10mm, direct sintering is used. Sintering temperature is 1530℃, boat pushing speed is 15mm / min, and the sintering medium is 120-mesh zirconia sand.
[0046] 4. Polishing heat treatment: Polishing frequency 220 Hz, time 2 hours. Vacuum heat treatment temperature 1250℃, holding time 3 hours.
[0047] 5. Final product performance and accuracy verification: The hardness of the obtained square fragment is 28.5 HRC, and the crushing deformation is 52.0%. Dimensionally, each side dimension is 5.0 mm, and the dimensional tolerance is controlled within ±0.05 mm.
[0048] Example 4: Preparation of 12mm×12mm×6mm high-toughness tungsten alloy square fragments This embodiment once again demonstrates the preparation of large-sized square fragments, comprehensively reflecting the synergistic effect of bidirectional pressure and double sintering.
[0049] 1. Ingredient mixing: The raw material ratio (wt.%) is: W 92.2%, Ni 5.0%, Fe 2.5%, Co 0.22%, Mn 0.08%. Alcohol is added at 320 mL / kg of powder, and the mixture is wet-milled for 38 hours.
[0050] 2. Granulation and pressing: After granulation, 56.8% of the material is 60-80 mesh. A square compact is pressed using bidirectional pressure, with a compact height of 14.35 mm, a pressing pressure of 4.8 tons, and a holding time of 4 seconds.
[0051] 3. Activation sintering: Activation treatment conditions are 650℃ for 38 hours. Two sintering processes are adopted: the first sintering temperature is 1470℃, the boat pushing speed is 13mm / min, and the shrinkage rate is 92.5%; the second sintering temperature is 1555℃, and the boat pushing speed is 10mm / min.
[0052] 4. Polishing heat treatment: Polishing frequency 180 Hz, time 2.5 hours. Vacuum heat treatment temperature 1285℃, holding time 5 hours.
[0053] 5. Final product performance and accuracy verification: The obtained square fragment has a hardness of 27.0 HRC and a crushing deformation of 54.5%. Dimensionally, its length and width are 12.0 mm with a tolerance of ±0.15 mm; the height is 6.0 mm with a tolerance of ±0.08 mm.
[0054] Therefore, the above embodiments fully verify that the method of the present invention can stably prepare tungsten alloy fragments with high hardness (24~29 HRC), high compressive toughness (compression deformation ≥50% without cracking), and high dimensional accuracy. The size range of the fragments is 1~20 mm, and the dimensional tolerances meet the following requirements: When the fragments are square: size 1~6mm, tolerance ±0.05mm; size 6~10mm, tolerance ±0.08mm; size 10~15mm, tolerance ±0.15mm; size 15~20mm, tolerance ±0.25mm; When the fragments are spherical: size 1~5mm, tolerance is ±0.05mm; size 5~10mm, tolerance is ±0.15mm; size 10~15mm, tolerance is ±0.25mm; size 15~20mm, tolerance is ±0.35mm.
[0055] In summary, the above embodiments fully verify the effectiveness and superiority of the method of the present invention in the preparation of tungsten alloy fragments of different shapes and sizes. By selecting specific parameters within the range described in this method, high-performance tungsten alloy fragments with high dimensional accuracy and crushability ≥50% can be stably prepared. Through innovative process flow, this invention effectively solves the technical problems of low fragment crushability and difficulty in controlling dimensional accuracy inherent in traditional methods, and has broad application prospects.
[0056] Embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.
[0057] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.
[0058] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.
[0059] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.
[0060] Contents not described in detail in this specification are prior art known to those skilled in the art. It is hereby indicated that the above description is intended to help those skilled in the art understand this invention, but does not limit the scope of protection of this invention. Any equivalent substitutions, modifications, improvements, or simplifications of the above descriptions that do not depart from the essential content of this invention fall within the scope of protection of this invention.
Claims
1. A method for preparing high-toughness tungsten alloy fragments, characterized in that, Includes the following steps: S1. Ingredient mixing: Using W powder, Ni powder, Fe powder, Co powder and Mn powder as raw materials, mix with alcohol and perform high-energy wet milling to produce a uniform mixed powder; S2. Granulation and pressing: The mixed powder is dried and granulated, and the granulated material is placed in a mold and pressed into a blank; wherein, when pressing spherical fragments, the mold has a central process ring; when pressing square fragments, a bidirectional pressing method is used. S3. Activation sintering: The compact is activated and sintered according to the compact size to obtain sintered preform fragments. For compacts with a size less than 10 mm, direct sintering is used, and for compacts with a size greater than or equal to 10 mm, two sintering processes are used. S4. Polishing heat treatment: Polish the sintered pre-formed fragments and perform vacuum heat treatment to obtain the high-toughness tungsten alloy fragments.
2. The method for preparing high-toughness tungsten alloy fragments according to claim 1, characterized in that, In step S1, the raw material composition by weight percentage is: W 92~94%, Ni 4~6%, Fe 1~3%, Co 0.1~1.0%, and Mn 0.01~0.1%.
3. The method for preparing high-toughness tungsten alloy fragments according to claim 1, characterized in that, In step S1, the amount of alcohol added is 200~500mL / kg of powder, and the high-energy wet milling time is 24~48 hours.
4. The method for preparing high-toughness tungsten alloy fragments according to claim 1, characterized in that, In step S2, the particle size range of the granulated material is 40~100 mesh, and the proportion of material with 60~80 mesh is not less than 50%.
5. The method for preparing high-toughness tungsten alloy fragments according to claim 1, characterized in that, In step S2, the width of the process ring of the spherical fragment is 1 / 8 to 1 / 4 of its compact height.
6. The method for preparing a high-toughness tungsten alloy fragment according to claim 1, characterized in that, In step S2, the pressure used to compress the square fragment is 0.5 to 5 tons, and the pressure holding time is 2 to 10 seconds.
7. The method for preparing high-toughness tungsten alloy fragments according to claim 1, characterized in that, In step S3, the activation treatment temperature is 500~800℃, and the activation time is 24~48 hours.
8. The method for preparing high-toughness tungsten alloy fragments according to claim 1, characterized in that, In step S3: The direct sintering temperature is 1515~1555℃, and the boat pushing speed is 8~15mm / min; The two sintering processes include: a first sintering temperature of 1430~1470℃ and a boat pushing speed of 10~20 mm / min; and a second sintering temperature of 1525~1565℃ and a boat pushing speed of 8~12 mm / min.
9. The method for preparing high-toughness tungsten alloy fragments according to claim 1, characterized in that, In step S4: The polishing frequency is 180~250Hz, and the polishing time is 1~3 hours; The vacuum heat treatment temperature is 1150~1350℃, the holding time is 2~5 hours, and the vacuum degree is lower than... Pa.
10. A high-toughness tungsten alloy fragment, prepared by the method for preparing a high-toughness tungsten alloy fragment according to any one of claims 1 to 9, characterized in that, The hardness of the fragment is 24~29HRC, the crushing deformation is ≥50% and it does not crack; its size range is 1~20 mm, and the dimensional tolerance meets the following requirements: When the fragments are square: size 1~6mm, tolerance ±0.05mm; size 6~10mm, tolerance ±0.08mm; size 10~15mm, tolerance ±0.15mm; size 15~20mm, tolerance ±0.25mm; When the fragments are spherical: size 1~5mm, tolerance is ±0.05mm; size 5~10mm, tolerance is ±0.15mm; size 10~15mm, tolerance is ±0.25mm; size 15~20mm, tolerance is ±0.35mm.