A preformed guide groove special-shaped penetrating body based on tungsten alloy additive manufacturing and a preparation method and application thereof

Abstract

The application provides a preformed guide groove special-shaped penetrating body based on tungsten alloy additive manufacturing and a preparation method and application thereof, and belongs to the technical field of penetrating body materials. In the application, the special-shaped penetrating body comprises a cylindrical base body and a guide groove preformed on the surface of the cylindrical base body; the cylindrical base body is made of tungsten alloy with a certain composition by additive manufacturing; and the guide groove is a straight guide groove, a spiral guide groove or a composite guide groove. The preformed guide groove special-shaped penetrating body based on tungsten alloy additive manufacturing provided by the application solves the problems of serious head blunting of a traditional penetrating body, low penetrating efficiency, poor flowability of tungsten alloy powder, many forming defects of the guide groove, lack of scientific basis for structural design and the like, realizes active regulation of plastic flow in the penetrating process, reduces the penetrating resistance, improves the penetration depth and damage efficiency, simultaneously establishes an integrated technical system of "material-structure-process-performance", and provides support for the research and development of similar high-performance national defense components.

Description

Technical Field

[0001] This invention relates to the field of penetrator materials technology, and in particular to a prefabricated guide groove irregular penetrator based on additive manufacturing of tungsten alloy, its preparation method and application. Background Technology

[0002] Penetrators are core payload components of weapon systems such as armor-piercing and high-explosive anti-tank projectiles, and their penetration efficiency directly determines the damage effectiveness of the equipment against armored targets. Traditional penetrators are mainly cylindrical tungsten alloys, manufactured using forging and machining processes. However, due to limitations in tool cutting capabilities and forming principles, it is impossible to precisely prefabricate guide groove structures with uniform dimensions and smooth walls on the cylindrical surface.

[0003] Under high-speed penetration conditions of 1500~2500 m / s, the head of a traditional cylindrical penetrator must withstand high pressure of 10~30 GPa and high temperature of 800~1200℃, which easily leads to plastic rheology and head passivation. This results in a 30%~50% increase in penetration resistance compared to the initial stage and a significant decrease in penetration depth. Head passivation has become the core bottleneck restricting the performance improvement of traditional penetrators. Existing research shows that guiding plastic flow and slag recirculation through structural design is an effective way to suppress passivation, but traditional machining processes are difficult to achieve precise forming of complex functional structures such as guide grooves.

[0004] Additive manufacturing technologies (such as selective laser melting, SLM) are based on the principle of "layer stacking," providing technical support for the precise prefabrication of guide grooves. However, there are three key problems in the current application of additive manufacturing of tungsten alloys: First, the powder has poor flowability (usually ≤15s / 50g), resulting in uneven powder distribution during the forming process, and microstructures such as guide grooves are prone to undermelting and edge collapse; Second, the density of the formed parts is relatively low (mostly between 95% and 97%), and defects such as internal pores and microcracks reduce the continuity of plastic flow of the material; Third, there is insufficient research on the coupling mechanism of "guide groove-plastic flow-penetration efficiency," and there is a lack of systematic structural design methods and mechanism support. Functional structural designs rely heavily on experience, making it difficult to achieve optimal performance.

[0005] While existing domestic and international research has achieved the preparation of additively manufactured tungsten alloys with high density or fluidity, it has not been specifically optimized for plastic flow properties, and the problem of insufficient forming accuracy of microstructures still exists. In terms of process optimization, powder flowability and elongation of formed parts still cannot meet the requirements for guiding plastic flow. Regarding the design of irregularly shaped penetrator structures, the precision limitations of traditional machining lead to unstable guide groove functions. Existing simulations and designs do not fully consider the multi-parameter coupling effect of guide grooves and the characteristics of additive manufacturing processes, resulting in significant deviations between simulation results and experiments. The lack of scientific design basis and full-chain coupling verification leads to a disconnect between mechanism analysis and engineering applications.

[0006] Therefore, developing a high-performance additive manufacturing tungsten alloy that adapts to the requirements of guide groove forming and plastic flow, establishing a scientific guide groove parameter design method, and realizing the precise manufacturing and performance improvement of irregularly shaped penetrators have become the key to solving the technical bottlenecks of traditional penetrators. Summary of the Invention

[0007] The purpose of this invention is to provide a prefabricated guide groove shaped penetrator based on additive manufacturing of tungsten alloy and its preparation method. The prefabricated guide groove shaped penetrator based on additive manufacturing of tungsten alloy provided by this invention solves the problems of severe head passivation, low penetration efficiency, poor flowability of additive manufacturing tungsten alloy powder, many defects in guide groove forming, and lack of scientific basis for structural design in traditional penetrators. It realizes active control of plastic flow during penetration, reduces penetration resistance, improves armor penetration depth and damage effectiveness, and establishes an integrated technical system of "material-structure-process-performance", providing support for the research and development of similar high-performance defense components.

[0008] To achieve the above-mentioned objectives, the present invention provides the following technical solution: The present invention provides a prefabricated guide groove irregular penetrator based on additive manufacturing of tungsten alloy, comprising a cylindrical substrate and a guide groove prefabricated on the surface of the cylindrical substrate; The cylindrical substrate is made of additively manufactured tungsten alloy; The tungsten alloy comprises the following chemical components by mass: W 88-96 parts, Ni 2-7 parts, Fe 1-6 parts, and Ti / Cr 0.07-0.5 parts; The guide groove is a straight guide groove, a spiral guide groove, or a composite guide groove; the straight guide groove is evenly distributed along the axial direction of the cylindrical base; the spiral guide groove is spirally distributed along the cylindrical base; the composite guide groove has a straight guide groove at the head and a spiral guide groove at the tail.

[0009] Preferably, the tungsten alloy has a density ≥88%, a tensile strength ≥1100MPa, and an elongation ≥8%.

[0010] Preferably, the forming accuracy of the guide groove is ±0.05mm, the roughness of the guide groove wall Ra≤1.6μm, and the defect rate of the guide groove is ≤1.5%.

[0011] Preferably, the number of guide grooves is 3 to 6, the groove depth of the guide groove is 0.5 to 2 mm, and the groove width of the guide groove is 0.8 to 2.5 mm.

[0012] Preferably, the helix angle of the spiral guide groove is 15°~45°; in the composite guide groove, the length of the head straight guide groove accounts for 1 / 3~1 / 2 of the total length of the irregular penetrator, and the length of the tail spiral guide groove accounts for 1 / 2~2 / 3 of the total length of the irregular penetrator.

[0013] The present invention also provides a method for preparing the heteromorphic penetrator described in the above technical solution, comprising the following steps: (1) Tungsten alloy powder was prepared by plasma rotating electrode atomization process; (2) Based on the structure of the target irregular penetrator, determine the initial parameters of the guide groove, and then use LS-DYNA software to construct a coupled simulation model. Optimize the initial parameters of the guide groove using the response surface methodology to obtain the optimized parameters of the guide groove. (3) Using the tungsten alloy powder obtained in step (1) as raw material, combined with the guide groove optimization parameters obtained in step (2), selective laser melting (SLM) technology is used to perform partitioned scanning or ring scanning strategy on the guide groove area to form an integral shape of the irregular penetrator. After vacuum annealing, a prefabricated guide groove irregular penetrator based on additive manufacturing tungsten alloy is obtained.

[0014] Preferably, in step (1), the sphericity of the tungsten alloy powder is ≥95%, the particle size distribution of the tungsten alloy powder is 15~53μm, the flowability of the tungsten alloy powder is ≥20s / 50g, and the loose packing density of the tungsten alloy powder is ≥10.5g / cm3.

[0015] Preferably, the SLM process parameters in step (3) include: laser power of 300~500W, scanning speed of 800~1200mm / s, layer thickness of 20~40μm, and scanning spacing of 80~120μm.

[0016] Preferably, after obtaining the prefabricated guide groove irregular penetrator based on additive manufacturing tungsten alloy in step (3), the method further includes: performing material performance testing, forming accuracy testing and penetration performance verification on the prefabricated guide groove irregular penetrator based on additive manufacturing tungsten alloy, and establishing a quantitative correlation model of "process-structure-mechanism-performance".

[0017] The present invention also provides an application of the irregular penetrator described in the above technical solution in projectile materials, high-temperature resistant components, or wear-resistant components.

[0018] Compared with the prior art, the prefabricated guide groove irregular penetrator based on additive manufacturing of tungsten alloy provided by the present invention has the following beneficial effects: Military value: This invention guides the plastic reflux of tungsten alloy and the discharge of target plate debris through a prefabricated guide groove structure, which significantly reduces the passivation of the penetrator head, reduces penetration resistance by 30%-50%, and greatly increases armor penetration depth. It can be directly applied to the development of new armor-piercing projectiles, solves the performance bottleneck of traditional penetrators, enhances the equipment's ability to destroy advanced armored targets, and provides key technical support for national defense security. Technical Value: This invention establishes an integrated technical system of "material performance regulation - precise structural forming - quantitative mechanism revelation - performance verification", which solves core problems such as poor flowability of tungsten alloy powder in additive manufacturing, numerous defects in guide groove forming, and lack of scientific basis for structural design, and provides a paradigm reference for the research and development of similar high-performance defense components; Industrial Value: The high-performance tungsten alloy powder preparation process, guide groove structure design method, and SLM process optimization technology developed in this invention can be extended to fields such as high-temperature resistant components for aerospace and wear-resistant components for high-end equipment, driving the technological upgrading of the tungsten alloy powder industry (increasing the production capacity of high-flowability powders) and the additive manufacturing equipment industry (optimizing the forming accuracy of complex structures); at the same time, it enhances the core competitiveness in the field of high-performance structural component manufacturing, and has significant economic and social benefits. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the spiral guide groove in this invention; Figure 2 This is a schematic diagram of the composite guide groove in this invention; Figure 3 The present invention is a flowchart of the SLM additive manufacturing process, wherein the SLM additive manufacturing process includes, in sequence: tungsten alloy powder preparation, part model design (i.e., determining the initial parameters of the guide groove based on the structure of the target irregular penetrator, then using LS-DYNA software to construct a coupled simulation model, and optimizing the initial parameters of the guide groove through response surface methodology to obtain the optimized parameters of the guide groove), 3D printing blank (i.e., integral forming of the irregular penetrator), powder cleaning, heat treatment (i.e., vacuum annealing), support removal, polishing, and finished product inspection; Figure 4 This is a schematic diagram of the penetration performance testing and verification device of the present invention, wherein the penetration performance testing and verification device includes a ballistic gun, a velocity measuring target, and a target plate. Detailed Implementation

[0020] The present invention provides a prefabricated guide groove irregular penetrator based on additive manufacturing of tungsten alloy, comprising a cylindrical substrate and a guide groove prefabricated on the surface of the cylindrical substrate; The cylindrical substrate is made of additively manufactured tungsten alloy; The tungsten alloy comprises the following chemical components by mass: W 88-96 parts, Ni 2-7 parts, Fe 1-6 parts, and Ti / Cr 0.07-0.5 parts; The guide groove is a straight guide groove, a spiral guide groove, or a composite guide groove; the straight guide groove is evenly distributed along the axial direction of the cylindrical base; the spiral guide groove is spirally distributed along the cylindrical base; the composite guide groove has a straight guide groove at the head and a spiral guide groove at the tail.

[0021] Unless otherwise specified, all raw materials used in this invention are commercially available products in the art.

[0022] In this invention, the density of the tungsten alloy is preferably ≥88%, the tensile strength of the tungsten alloy is preferably ≥1100MPa, and the elongation of the tungsten alloy is preferably ≥8%. This invention controls the density and tensile strength of the tungsten alloy within the above ranges to prevent internal porosity, microcracks, etc., from reducing the plastic flowability of the tungsten alloy material, leading to structural instability and breakage of the penetrator, and reducing its penetration ability. Controlling the elongation to ≥8% ensures that it meets the plastic flow guidance requirements of the prefabricated guide groove.

[0023] In this invention, the forming accuracy of the guide groove is preferably ±0.05 mm, the wall roughness Ra of the guide groove is preferably ≤1.6 μm, and the defect rate of the guide groove is preferably ≤1.5%. This invention controls the forming accuracy, wall roughness Ra, and defect rate of the guide groove within the above ranges to avoid functional instability caused by excessively low forming accuracy, excessively high wall roughness, and high defect rate, which would reduce the plastic flow guiding effect of the guide groove during penetration. Therefore, it is necessary to control the minimum standards of each parameter within the above ranges to ensure that the desired effect is achieved.

[0024] In this invention, the number of guide grooves is preferably 3 to 6, the groove depth is preferably 0.5 to 2 mm, and the groove width is preferably 0.8 to 2.5 mm. This invention controls the number, depth, and width of the guide grooves within the above ranges to avoid excessive guide grooves or excessive depth and width, which would lead to a decrease in the quality of the penetrant and reduce its penetration performance. Conversely, insufficient guide grooves would reduce its plastic flow guiding ability and fail to achieve the desired effect.

[0025] In this invention, the helix angle of the spiral guide groove is preferably 15°~45°. By controlling the helix angle of the spiral guide groove within this range, the invention ensures good guiding effect without increasing penetration resistance or decreasing guiding effect due to excessive angle. In this invention, the length of the head straight guide groove in the composite guide groove is preferably 1 / 3 to 1 / 2 of the total length of the irregularly shaped penetrating body, and the length of the tail spiral guide groove is preferably 1 / 2 to 2 / 3 of the total length of the irregularly shaped penetrating body. By controlling the lengths of the head and tail of the composite guide groove within the above range, the straight guide groove facilitates faster slag discharge in the early stages of penetration, reducing penetration resistance, while the spiral guide groove provides better guiding effect in the middle and later stages of penetration. Therefore, the length of the head straight guide groove should not be too long.

[0026] The present invention also provides a method for preparing the heteromorphic penetrator described in the above technical solution, comprising the following steps: (1) Tungsten alloy powder was prepared by plasma rotating electrode atomization process; (2) Based on the structure of the target irregular penetrator, determine the initial parameters of the guide groove, and then use LS-DYNA software to construct a coupled simulation model. Optimize the initial parameters of the guide groove using the response surface methodology to obtain the optimized parameters of the guide groove. (3) Using the tungsten alloy powder obtained in step (1) as raw material, combined with the guide groove optimization parameters obtained in step (2), selective laser melting (SLM) technology is used to perform partitioned scanning or ring scanning strategy on the guide groove area to form an integral shape of the irregular penetrator. After vacuum annealing, a prefabricated guide groove irregular penetrator based on additive manufacturing tungsten alloy is obtained.

[0027] In this invention, the sphericity of the tungsten alloy powder is preferably ≥95%, the particle size distribution of the tungsten alloy powder is preferably 15~53μm, the flowability of the tungsten alloy powder is preferably ≥20s / 50g, and the loose packing density of the tungsten alloy powder is preferably ≥10.5g / cm³. 3 This invention controls the sphericity, particle size distribution, flowability, and loose packing density of tungsten alloy powder within the aforementioned ranges. High sphericity ensures the uniformity of the billet's microstructure, and uniform deformation during penetration improves penetration efficiency. A reasonable particle size distribution increases the initial loose packing density of the powder layer, resulting in low shrinkage after laser melting and reducing the likelihood of shrinkage porosity and microcracks. Flowability and loose packing density requirements primarily ensure forming quality, reduce forming defects, and guarantee the mechanical properties of the penetrated body.

[0028] In this invention, the preferred Ni / Fe ratio in the tungsten alloy powder is (1~2):1. This invention improves powder flowability to ≥20s / 50g and loose packing density to ≥10.5g / cm³ by adjusting the alloy element ratio (Ni / Fe ratio) and adding trace amounts of Ti / Cr modifying elements. 3In this invention, the tungsten alloy powder is preferably vacuum dried at 110-130°C for 3-5 hours before use. This vacuum drying process removes moisture and impurities, ensuring uniform powder distribution during subsequent preparation.

[0029] In this invention, the design and simulation optimization of the target irregular penetrator structure are preferably based on plastic flow and slag discharge requirements to determine the initial parameters of the guide channel. In this invention, the initial parameters of the guide channel preferably include type, quantity, depth, width, and helix angle.

[0030] In this invention, the preferred SLM process parameters include: laser power of 300-500W, scanning speed of 800-1200mm / s, layer thickness of 20-40μm, and scanning spacing of 80-120μm. This invention controls the SLM process parameters within the above range to avoid fusion defects caused by insufficient energy when the laser power is below 300W, while laser power above 500W can easily lead to severe vaporization of the tungsten alloy, forming porosity. The scanning speed range ensures stable and continuous melting of the molten pool while achieving rapid solidification, resulting in a uniform and fine equiaxed grain structure. Simultaneously, it controls residual stress and deformation, significantly reducing anisotropy in mechanical properties. The layer thickness needs to be matched with the laser power and scanning speed to reduce interlayer metallurgical bonding defects, while balancing forming quality and engineering processing efficiency. An appropriate scanning spacing can reduce the interaction between molten pools during melting, reduce unfused defects, and improve the compressive strength of the material. However, when the scanning spacing reaches a certain limit and continues to increase, the uniformity and continuity of the material are affected, leading to a decrease in compressive strength.

[0031] In this invention, the integral forming process of the irregularly shaped penetrator preferably employs inert gas protection, with an oxygen content preferably ≤50ppm. The use of inert gas protection during the forming process prevents oxidation of the tungsten alloy. After the integral forming of the irregularly shaped penetrator is completed, the process preferably includes powder removal. This invention does not impose any special restrictions on the powder removal method; any well-known technical solution can be used. In this invention, the vacuum annealing temperature is preferably 1000~1200℃, and the holding time is preferably 2~4h. This invention controls the vacuum annealing temperature and holding time within the above range to eliminate internal residual stress and improve material plasticity. After the vacuum annealing process is completed, the process preferably further includes: sequentially performing support removal, polishing, and finished product inspection. This invention does not impose any special restrictions on the methods of support removal, polishing, and finished product inspection; any well-known technical solution can be used.

[0032] In this invention, after obtaining the prefabricated guide groove irregular penetrator based on additive manufacturing tungsten alloy, it is preferable to further include: performing material performance testing, forming accuracy testing and penetration performance verification on the prefabricated guide groove irregular penetrator based on additive manufacturing tungsten alloy, and establishing a quantitative correlation model of "process-structure-mechanism-performance".

[0033] In this invention, the integral forming process of the irregular penetrator is preferably carried out using high-speed photography (frame rate ≥ 10). 5 The penetration process is recorded at fps. In this invention, the material performance testing preferably employs a split Hopkinson bar technique at 10 fps. 2 ~10 4 s -1 Dynamic mechanical properties were tested under strain rate, and the degree of head passivation was analyzed using CT scans.

[0034] The present invention also provides an application of the irregular penetrator described in the above technical solution in projectile materials, high-temperature resistant components, or wear-resistant components.

[0035] In this invention, the projectile material is preferably an armor-piercing projectile material. In this invention, the high-temperature resistant component is preferably an aerospace high-temperature resistant component. In this invention, the wear-resistant component is preferably a high-end equipment wear-resistant component.

[0036] The technical solutions of this invention will be clearly and completely described below with reference to the embodiments thereof. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0037] Unless otherwise specified, all experiments were repeated three times, and the results are expressed as averages.

[0038] Example 1 A prefabricated guide groove shaped penetrator based on additive manufacturing of tungsten alloy (hereinafter referred to as a spiral guide groove shaped penetrator) consists of a cylindrical base and a guide groove prefabricated on the surface of the cylindrical base; The cylindrical substrate is made of additively manufactured tungsten alloy; The tungsten alloy comprises the following chemical components by mass: 92 parts W, 4 parts Ni, 3.8 parts Fe, and 0.2 parts Ti; The guide groove is a spiral guide groove with a helix angle of 30°; the spiral guide groove is spirally distributed along the cylindrical base. The density of the tungsten alloy is ≥88%, the tensile strength of the tungsten alloy is ≥1100MPa, and the elongation of the tungsten alloy is ≥8%. The forming accuracy of the guide groove is ±0.05mm, the wall roughness Ra of the guide groove is ≤1.6μm, and the defect rate of the guide groove is ≤1.5%. The number of guide grooves is 4, the depth of the guide grooves is 1.2mm, and the width of the guide grooves is 1.5mm.

[0039] The above-mentioned method for preparing prefabricated guide groove irregular penetrators based on additive manufacturing of tungsten alloys includes the following steps: (1) Tungsten alloy powder was prepared by plasma rotating electrode atomization (PREP) process. The tungsten alloy powder, by mass parts, included the following chemical components: W 92 parts, Ni 4 parts, Fe 3.8 parts, and Ti 0.2 parts. By adjusting the atomization voltage and current parameters, tungsten alloy powder with a sphericity of 96% and a particle size distribution of 15-53 μm was obtained. The mass ratio of Ni / Fe in the tungsten alloy powder was 1.05:1. After the tungsten alloy powder was vacuum dried at 120℃ for 4 h, the flowability of the tungsten alloy powder was measured to be 21 s / 50 g, and the loose packing density was 10.8 g / cm³. 3 To meet the forming requirements; (2) The design and simulation optimization of the target irregular penetrator structure are based on plastic flow and slag discharge requirements. The initial parameters of the guide channel are determined as follows: the type is a spiral guide channel, the number of channels is 4, the channel depth is 1.2 mm, the channel width is 1.5 mm, and the spiral angle is 30°. The coupled simulation model is constructed using LS-DYNA software. The Johnson-Cook constitutive model is selected for the penetrator (the parameters are calibrated by experiments). The initial penetration velocity is set to 2000 m / s. The optimized parameters of the guide channel are obtained by response surface methodology. The simulation prediction penetration depth error is ≤5%. (3) Using the tungsten alloy powder obtained in step (1) as raw material, combined with the guide groove optimization parameters obtained in step (2), selective laser melting (SLM) technology is used to perform partitioned scanning strategy on the guide groove area to form an integral irregular penetrator, clean the powder, perform vacuum annealing, and then perform support removal, polishing and finished product inspection in sequence to obtain a prefabricated guide groove irregular penetrator based on additive manufacturing of tungsten alloy; The SLM process parameters are as follows: laser power 400W, scanning speed 1000mm / s, layer thickness 30μm, scanning spacing 100μm; the guide groove area adopts a ring scanning strategy; argon gas is introduced for protection during the integral forming process of the irregular penetrator (oxygen content ≤50ppm); the vacuum annealing treatment is a heat treatment at 1100℃ for 3h.

[0040] The performance of the prefabricated guide groove irregular penetrator based on additively manufactured tungsten alloy prepared in Example 1 was tested. Density was determined using the Archimedes displacement method; tensile strength and elongation were determined using a universal testing machine with room temperature quasi-static tensile testing; and dynamic compressive strength was determined using a split Hopkinson bar. The test results are as follows: Material properties: density 98.5%, tensile strength 1120 MPa, elongation 8.5%, dynamic compressive strength (10 3 s -1 Strain rate: 2800 MPa; Forming accuracy: guide groove dimensional accuracy ±0.04 mm, groove wall roughness Ra 1.2 μm, internal defect rate 1.2%; Penetration performance: In indoor simulated penetration tests (initial velocity 2000m / s, armored steel target plate), the penetration depth is increased by 42% compared with the traditional cylindrical penetrator, and the head passivation is reduced by 60%; the performance is stable under high and low temperature and different speed conditions, with a deviation of ≤3%.

[0041] Example 2 A prefabricated guide groove shaped penetrator based on additive manufacturing of tungsten alloy (referred to as composite guide groove shaped penetrator) consists of a cylindrical substrate and a guide groove prefabricated on the surface of the cylindrical substrate; The cylindrical substrate is made of additively manufactured tungsten alloy; The tungsten alloy comprises the following chemical components by mass: 93 parts W, 3.5 parts Ni, 3.3 parts Fe, and 0.2 parts Cr; The guide groove is a composite guide groove; the head of the composite guide groove is a straight guide groove and the tail is a spiral guide groove, and the spiral angle of the tail spiral guide groove is 25°; in the composite guide groove, the length of the head straight guide groove accounts for 1 / 3 of the total length of the irregular penetrator, and the length of the tail spiral guide groove accounts for 2 / 3 of the total length of the irregular penetrator. The density of the tungsten alloy is ≥88%, the tensile strength of the tungsten alloy is ≥1100MPa, and the elongation of the tungsten alloy is ≥8%. The forming accuracy of the guide groove is ±0.05mm, the wall roughness Ra of the guide groove is ≤1.6μm, and the defect rate of the guide groove is ≤1.5%. The number of guide grooves is 5, the depth of the guide groove is 1.0 mm, and the width of the guide groove is 1.2 mm.

[0042] The above-mentioned method for preparing prefabricated guide groove irregular penetrators based on additive manufacturing of tungsten alloys includes the following steps: (1) Tungsten alloy powder was prepared by plasma rotating electrode atomization (PREP) process. The tungsten alloy powder, by mass parts, included the following chemical components: W 93 parts, Ni 3.5 parts, Fe 3.3 parts, and Cr 0.2 parts. By adjusting the atomization voltage and current parameters, tungsten alloy powder with a sphericity of 95% and a particle size distribution of 15-53 μm was obtained. The mass ratio of Ni / Fe in the tungsten alloy powder was 1.05:1. After the tungsten alloy powder was vacuum dried at 120℃ for 4 h, the flowability of the tungsten alloy powder was measured to be 20 s / 50 g, and the loose packing density was 10.6 g / cm³. 3 To meet the forming requirements; (2) The design and simulation optimization of the target irregular penetrator structure are based on plastic flow and slag discharge requirements. The initial parameters of the guide channel are determined as follows: the type is a spiral guide channel, the number of channels is 5, the channel depth is 1.0 mm, the channel width is 1.2 mm, and the spiral angle is 25°. The coupled simulation model is constructed using LS-DYNA software. The Johnson-Cook constitutive model is selected for the penetrator (the parameters are calibrated by experiments). The initial penetration velocity is set to 2000 m / s. The optimized parameters of the guide channel are obtained by response surface methodology. The simulation prediction penetration depth error is ≤4.5%. (3) Using the tungsten alloy powder obtained in step (1) as raw material, combined with the guide groove optimization parameters obtained in step (2), selective laser melting (SLM) technology is used to perform partitioned scanning strategy on the guide groove area to form an integral irregular penetrator, clean the powder, perform vacuum annealing, and then perform support removal, polishing and finished product inspection in sequence to obtain a prefabricated guide groove irregular penetrator based on additive manufacturing of tungsten alloy; The SLM process parameters are as follows: laser power 380W, scanning speed 900mm / s, layer thickness 25μm, scanning spacing 90μm; the guide groove area adopts a partitioned scanning strategy; argon gas is introduced for protection during the integral forming process of the irregular penetrator (oxygen content ≤50ppm); the vacuum annealing treatment is a heat treatment at 1050℃ for 3.5h.

[0043] Following the same method as in Example 1, the performance of the prefabricated guide groove irregular penetrator based on additively manufactured tungsten alloy prepared in Example 2 was tested, and the results are as follows: Material properties: density 98.2%, tensile strength 1110 MPa, elongation 8.2%; Forming accuracy: Guide groove dimensional accuracy ±0.05mm, groove wall roughness Ra1.4μm, internal defect rate 1.3%; Penetration performance: The penetration depth is increased by 38% compared with the traditional cylindrical penetrator, the head passivation is reduced by 55%, and the stability under working conditions is good.

[0044] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A prefabricated guide groove irregular penetrator based on additive manufacturing of tungsten alloy, characterized in that, It includes a cylindrical base and a guide groove pre-formed on the surface of the cylindrical base; The cylindrical substrate is made of additively manufactured tungsten alloy; The tungsten alloy comprises the following chemical components by mass: W 88-96 parts, Ni 2-7 parts, Fe 1-6 parts, and Ti / Cr 0.07-0.5 parts; The guide groove is a straight guide groove, a spiral guide groove, or a composite guide groove; the straight guide groove is evenly distributed along the axial direction of the cylindrical base; the spiral guide groove is spirally distributed along the cylindrical base; the composite guide groove has a straight guide groove at the head and a spiral guide groove at the tail.

2. The irregular penetrator according to claim 1, characterized in that, The tungsten alloy has a density ≥88%, a tensile strength ≥1100MPa, and an elongation ≥8%.

3. The irregular penetrator according to claim 1, characterized in that, The forming accuracy of the guide groove is ±0.05mm, the roughness of the guide groove wall Ra≤1.6μm, and the defect rate of the guide groove ≤1.5%.

4. The heteromorphic penetrator according to claim 1 or 3, characterized in that, The number of guide grooves is 3 to 6, the groove depth is 0.5 to 2 mm, and the groove width is 0.8 to 2.5 mm.

5. The irregular penetrator according to claim 1, characterized in that, The helix angle of the spiral guide groove is 15°~45°; in the composite guide groove, the length of the head straight guide groove accounts for 1 / 3~1 / 2 of the total length of the irregular penetrator, and the length of the tail spiral guide groove accounts for 1 / 2~2 / 3 of the total length of the irregular penetrator.

6. A method for preparing the heteromorphic penetrator according to any one of claims 1 to 5, characterized in that, Includes the following steps: (1) Tungsten alloy powder was prepared by plasma rotating electrode atomization process; (2) Based on the structure of the target irregular penetrator, determine the initial parameters of the guide groove, and then use LS-DYNA software to construct a coupled simulation model. Optimize the initial parameters of the guide groove using the response surface methodology to obtain the optimized parameters of the guide groove. (3) Using the tungsten alloy powder obtained in step (1) as raw material, combined with the guide groove optimization parameters obtained in step (2), selective laser melting (SLM) technology is used to perform partitioned scanning or ring scanning strategy on the guide groove area to form an integral shape of the irregular penetrator. After vacuum annealing, a prefabricated guide groove irregular penetrator based on additive manufacturing tungsten alloy is obtained.

7. The preparation method according to claim 6, characterized in that, In step (1), the sphericity of the tungsten alloy powder is ≥95%, the particle size distribution of the tungsten alloy powder is 15~53μm, the flowability of the tungsten alloy powder is ≥20s / 50g, and the loose packing density of the tungsten alloy powder is ≥10.5g / cm³. 3 .

8. The preparation method according to claim 6, characterized in that, The SLM process parameters in step (3) include: laser power of 300~500W, scanning speed of 800~1200mm / s, layer thickness of 20~40μm, and scanning spacing of 80~120μm.

9. The preparation method according to claim 6, characterized in that, After obtaining the prefabricated guide groove shaped penetrator based on additive manufacturing tungsten alloy in step (3), the method further includes: performing material performance testing, forming accuracy testing and penetration performance verification on the prefabricated guide groove shaped penetrator based on additive manufacturing tungsten alloy, and establishing a quantitative correlation model of "process-structure-mechanism-performance".

10. The application of the irregular penetrator as described in any one of claims 1 to 5 in projectile materials, high-temperature resistant components, or wear-resistant components.

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