An anti-penetration multi-component alloy and its preparation method

Abstract

The present application discloses an anti-penetration multi-component alloy and a preparation method thereof, which relates to the field of alloy material preparation; the chemical formula of the multi-component alloy is Co<subgt;2< / subgt;Ni<subgt;2< / subgt>CrVTa<subgt;x< / subgt>, where x = 0.1, 0.3 or 0.5; by regulating the content of Ta element in the present application, when the multi-component alloy obtains a micron-scale reticular Laves phase, there is also a nano-scale L1<subgt;2 structural precipitation phase. Due to the synergistic strengthening of the two multi-scale precipitation phases, the room-temperature tensile yield strength of the alloy > 500 MPa, the elongation > 20%, and the ballistic limit velocity > 420 m / s (for 3-mm-thick plates); in addition, the preparation process of the multi-component alloy is simple, has excellent fluidity, is suitable for industrial production, and has good application prospects in the field of armor protection materials.

Description

Technical Field

[0001] The present application relates to the field of alloy material preparation, and particularly to an anti-penetration multi-component alloy material and a preparation method thereof. Background Art

[0002] Multi-component alloys refer to alloys composed of three or more elements in equimolar ratio or near-equimolar ratio. The contents of these alloy elements are similar, usually between 5% and 35%. As a new type of metallic material, multi-component alloys have unique microstructures and good mechanical properties, especially excellent strain hardening ability, which makes them have good application prospects in the field of anti-penetration.

[0003] Anti-penetration technology generally refers to using materials and technical means with high strength, high hardness and high toughness to resist the penetration of projectiles or other penetrators, so as to protect the target structure from damage. This technology has wide applications in both military and civilian fields, especially in protective engineering. With the rapid development of national defense technology, higher requirements are put forward for armor protection materials: on the one hand, the significant increase in the penetration speed of external projectiles or fragments has continuously improved the protection level; on the other hand, due to the special requirements of armor mobility and scientific research tests, designing excellent alloy microstructures to improve their properties has also become a research direction for anti-penetration materials. Therefore, there is an urgent need to design multi-component alloy materials with excellent anti-penetration performance. Summary of the Invention

[0004] In view of the above problems, the present application discloses a multi-component alloy material and its application to improve the anti-penetration performance of multi-component alloys.

[0005] Specifically, the present application provides the following technical solutions:

[0006] First, the present application provides an anti-penetration multi-component alloy with the chemical formula Co2Ni2CrVTa x , and the components of the alloy are composed according to the molar ratio of the subscripts in the chemical formula, where x takes any one of 0, 0.1, 0.3 or 0.5. By regulating the content of Ta element, the alloy simultaneously has a micron-scale network Laves phase and a nano-scale L12 structure precipitation phase. The room-temperature tensile yield strength of the alloy is >500 MPa, the elongation is >20%, and the ballistic limit velocity is >420 m / s (for 3-mm-thick plates).

[0007] Furthermore, x preferably takes the value of 0.3, and the obtained structural formula is Co2Ni2CrVTa 0.3 , and there are both network micron-scale Laves phases and nano-scale L12 structure precipitation phases in the alloy.

[0008] Secondly, the present application provides a method for preparing the above anti-penetration multi-component alloy, and the specific steps are as follows:

[0009] 1) Weigh the raw materials of 5 components, namely Co, Ni, Cr, V, and Ta, according to the molar ratio of 2:2:1:1:x, and the purity of each component raw material ≥ 99.9 wt%; x takes any one of 0, 0.1, 0.3, or 0.5;

[0010] 2) Vacuum arc melting: The melting furnace is evacuated to a vacuum degree of 9×10 -4 Pa to 1×10 -3 Pa, then an inert gas (such as argon) is filled to -0.03 MPa to -0.02 MPa, and finally the Ti ingot is melted 3 to 5 times, with each time lasting 60 s to 80 s;

[0011] 3) Arrange the weighed raw materials of each component in the order of increasing melting point, and place the component raw materials with a lower melting point on the heated surface of the melting container; stack Ni, Co, Cr, V, and Ta in sequence from bottom to top in the melting furnace, and then conduct high-vacuum arc melting on the raw materials 5 to 6 times, with the melting current being 240 A to 270 A, and the arc lasting for 2 min to 3 min each time. Subsequently, vacuum suction casting is performed on the metal solution to obtain the above alloy.

[0012] Preferably, when each component raw material is melted into a liquid state, electromagnetic stirring is performed 5 to 6 times between two meltings, the electromagnetic stirring current is 1.5 A to 2.5 A, and the duration of each time is 1 min to 2 min.

[0013] After the melting is completed, the above Co2Ni2CrVTa x alloy (x takes 0, 0.1, 0.3, or 0.5) is obtained.

[0014] Compared with the prior art, the multi-component alloy with the structural formula of Co2Ni2CrVTa x (x takes 0, 0.1, 0.3, or 0.5) provided by the present application designs a multi-scale co-strengthened multi-component alloy of FCC phase + reticular Laves phase + L12 structure precipitation phase. It is similar to adding a steel mesh and concrete particles to concrete in the construction field to improve the comprehensive performance of concrete. The micron-sized reticular Laves phase is equivalent to the steel mesh, and the nano-sized L12 precipitation phase is equivalent to fine concrete particles. The two cooperate to strengthen and further improve the alloy strength and anti-penetration ability.

[0015] According to the different contents of the Ta element, Co2Ni2CrVTa xThe yield strength of the multi-component alloy is 305 MPa to 537 MPa, the elongation is 63.8% to 24.4%, and the ballistic limit velocity is 407.8 m / s to 435.4 m / s. When x = 0.3, the alloy exhibits excellent anti-penetration performance and excellent tensile properties. In addition, the energy absorption of the alloy during penetration at different speeds was tested (450 m / s to 750 m / s), Co2Ni2CrVTa 0.3 The energy absorption increase of the alloy compared to the Co2Ni2CrV alloy is significantly higher at a penetration speed of 750 m / s than at 450 m / s. The energy absorption increase at 750 m / s is 27.7%, indicating that Co2Ni2CrVTa 0.3 The alloy has more excellent anti-penetration performance at higher speeds.

[0016] The design method of the present invention is simple and feasible. At the same time, the combination of excellent anti-penetration performance and mechanical properties provides a new multi-component alloy material for the field of armor protection materials. The multi-component alloy and the strengthening strategy can be widely applied to protection engineering (such as the field of armor protection), greatly broadening the application of multi-component alloys in the field of armor protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings forming a part of this application are used to provide a further understanding of this application. The schematic embodiments and descriptions thereof of this application are used to explain this application and do not constitute a limitation to this application. In the drawings:

[0018] Figure 1 It is a schematic diagram of the ballistic penetration test device for the embodiment.

[0019] Figure 2 It is a physical photo of the alloy prepared in Example 1.

[0020] Figure 3 It is the XRD test results of the multi-component alloys in Example 1, Comparative Example 1 and Comparative Example 2.

[0021] Figure 4 It is the SEM image of the L12 precipitation phase in the multi-component alloy in Example 1; among them, (a)-(d) are the test results of Co2Ni2CrVTa x alloy when x = 0, 0.1, 0.3, 0.5 respectively.

[0022] Figure 5 It is the characterization test results of the multi-component alloys in Example 1 and the comparative examples.

[0023] Figure 6 It is the tensile stress-strain curve of the multi-component alloys in Example 1 and the comparative examples.

[0024] Figure 7Fitting curves of the ballistic penetration limit velocities of multi-component alloys in Example 1 and Comparative Examples.

[0025] Figure 8 Energy absorption diagrams of multi-component alloys at different penetration velocities in Examples and Comparative Examples. Specific Embodiments

[0026] It should be noted that, without conflict, the embodiments in this application and the features in the embodiments can be combined with each other. The following will describe this application in detail with reference to the drawings and in combination with the embodiments.

[0027] 1) Reagents

[0028] Details of the main raw materials and reagents commonly used in the following embodiments are shown in Table 1.

[0029] Table 1 (All purchased from Hebei Luohong Technology Co., Ltd.)

[0030]

[0031] The above component raw materials Co, Ni, Cr, V, Ta are all industrial-grade raw materials with a purity ≥ 99.9 wt%. And before use, the Co, Ni, Cr, V, Ta metal particles are ultrasonically cleaned (40KHZ, 5min) with absolute ethanol respectively to obtain clean metal particles (φ3*3mm), so as to ensure the accurate weighing amount and no impurities.

[0032] 2) Performance Testing and Structure Characterization

[0033] (1) Phase Analysis: The X-ray diffraction spectrum of the alloy is measured by a D8 advance X-ray diffractometer of Bruker AXS company. The scanning angle range of the instrument measurement is 25° - 100°. Cu target K α rays are used. The working voltage of the equipment is 40 kV, the scanning speed is 0.2 sec / step, the step size is 0.02° / step, and the measurement angle error is less than 0.01°.

[0034] (2) Microstructure: The alloy is characterized by a Quanta-200 field emission scanning electron microscope of Semplor company, with a working voltage of 20 kV; the nano-sized precipitated phases are characterized by a JEM-2100 transmission electron microscope of JEOL company in Japan.

[0035] (3) Tensile Test: The mechanical properties of the multi-component alloy material are tested by an E44.304-B type electronic universal testing machine. The dimensions of the tensile specimen are 2 mm gauge width, 2 mm gauge thickness and 6 mm gauge width, and the tensile rate is 0.5 mm / min.

[0036] (4)Ballistic penetration test: The experimental device is as Figure 1 shown. The test system consists of a high-pressure air pump, an air chamber, a solenoid valve, a launch tube, a housing, a protection box, a high-speed camera, a light source, and a laser velocimeter. This system is a conventional detection system in this field, as disclosed in the literature "Y.H. Xiang, Z.W. Zhang, X.N. Yang, Y. Lin, G.K. Zhang, M.Q. Sun, F.G. Yan, M.Y. Wang, Failure mechanism of carbon / ultra-high molecular weight polyethylene twill fiber reinforced hybrid laminates under ballistic impact, Mater. Des. 216 (2022) 110578." According to the GJB 4300 A-2100 standard, a tungsten alloy projectile (Hebei Luohong Technology Co., Ltd.) with a diameter of 6 mm of YG6 is used to conduct a ballistic penetration test on an alloy plate with dimensions of 100 mm × 100 mm × 3 mm.

[0037] 3) Experimental equipment

[0038] The arc melting furnace used in the examples is a WK-II type non-consumable vacuum arc melting furnace purchased from Beijing Wuko Guangdian Technology Co., Ltd.;

[0039] Example 1 Preparation of multi-component alloy material Co2Ni2CrVTa 0.3

[0040] including the following steps:

[0041] Step 1: Weigh the component raw materials Co, Ni, Cr, V, and Ta in turn according to the molar ratio of the subscripts of each component in the chemical formula Co2Ni2CrVTa 0.3 in the chemical formula.

[0042] Step 2: The specific melting steps are as follows:

[0043] 2.1) In order to avoid the presence of harmful gases in the vacuum arc melting furnace so as not to affect the performance of the alloy, before melting, first use a molecular pump or a vacuum pump to pump the vacuum degree of the arc furnace to 9×10 -4 Pa. The vacuum degree within the above range can prevent the alloy from oxidizing during the melting process, and then argon gas (purity ≥ 99.999 vol.%) is filled to -0.05 MPa.

[0044] 2.2) The Ti ingot is melted 5 times, each time for 60 s, with an interval of 60 s, and the melting current is 240 A.

[0045] 2.3) Put the raw materials of each component weighed in Step 1 into a vacuum arc melting furnace. In order to prevent the raw material components with low melting points from volatilizing due to heat, stack the raw materials of each component in the order of increasing melting point, that is, Ni, Co, Cr, V, and Ta. Place the component raw material Ni with the lowest melting point at the bottom of the crucible, and stack the remaining component raw materials one by one. Then carry out melting under helium protection. The melting current is 240 A, the arc lasts for 3 minutes each time, and the interval between two meltings is 3 minutes; melt repeatedly 6 times; then vacuum suction cast the metal solution into a mold, and then cool it with the furnace. In specific implementation, melting for 3 - 5 minutes each time and having an interval of 3 - 5 minutes can achieve the purpose of the invention.

[0046] During melting, after the alloy is transformed from a solid state to a liquid state, during the interval between two meltings, turn on the electromagnetic stirring of the device (the electromagnetic stirring current is within the safe allowable range of the vacuum arc melting furnace). In this embodiment, the stirring current is 1.5 A, and the duration of each stirring is 2 minutes. After electromagnetic stirring, the liquid metal has good fluidity, the alloying elements can be fully fused, and the alloy performance reaches the best state.

[0047] The photo of the alloy plate (100mm×100mm×3mm) prepared in this embodiment is as Figure 2 shown.

[0048] Perform XRD, SEM, TEM characterization, tensile property, and anti - penetration property detection on the alloy prepared in this embodiment. The specific results are as follows:

[0049] 1) Characterization results

[0050] (1) The XRD detection results are as shown in Figure 3 (0.3Ta). It can be seen that the Co2Ni2CrVTa 0.3 alloy is composed of FCC phase and HCP Laves phase.

[0051] (2) Figure 4 In (c) is the SEM image of the Co2Ni2CrVTa 0.3 alloy. It can be seen that the micron - sized Laves phase is distributed in a network pattern in the alloy.

[0052] (3) The TEM results are as shown in Figure 5 shown. Figure 5 In it, (a) is the low - magnification TEM bright - field image, (b) is the high - magnification TEM bright - field image, (c) is the diffraction pattern of the L12 - structure precipitation phase and the matrix, (d) is the high - resolution TEM image and the inverse Fourier transform image of the matrix and the precipitation phase, (e) is the geometric phase analysis of the L12 - structure precipitation phase. It can be seen that the Co2Ni2CrVTa 0.3There are also precipitates with a size of 3 nm in the alloy. It is determined by diffraction spots that the nano-sized precipitates are of the L12 structure; the interplanar spacings of the matrix and the L12-structured precipitates are 1.86 Å and 1.58 Å, respectively; the strain of the precipitates is significantly higher than that of the matrix, thus further strengthening the mechanical properties of the alloy.

[0053] 2) Performance test results

[0054] (1) Figure 6 In the curve of 0.3Ta, it is Co2Ni2CrVTa 0.3 The stress-strain curve of the alloy shows that its ultimate tensile strength is ~761 MPa, the yield strength is ~537 MPa, and the elongation is ~24.4%.

[0055] (2) The fitting curve of the ballistic penetration limit velocity is as Figure 7 shown, and it can be seen that the ballistic limit velocity of Co2Ni2CrVTa 0.3 alloy is ~435.4 m / s.

[0056] (3) The energy absorption of the alloy at different penetration velocities is as Figure 8 shown. At the penetration velocities of 450 m / s, 550 m / s, 650 m / s, and 750 m / s, the energy absorptions of Co2Ni2CrVTa 0.3 alloy are 157.2 J, 175.2 J, 191.4 J, and 226.2 J, respectively. Compared with Comparative Example 1 (Co2Ni2CrV), Co2Ni2CrVTa 0.3 alloy has the most excellent energy absorption increase at a velocity of 750 m / s, and the increase is ~27.7%.

[0057] Comparative Example 1

[0058] Alloys with the chemical formulas Co2Ni2CrV and Co2Ni2CrVTa are prepared by the same steps as in Example 1, and are composed according to the molar ratios of the subscripts in the chemical formulas among the components. 0.1 The Co2Ni2CrV and Co2Ni2CrVTa

[0059] alloys are characterized by XRD, SEM, and tested for tensile properties and penetration properties. The specific results are as follows: 0.1 1) Characterization results

[0060] (1) The XRD results are as

[0061] shown. It can be seen that only the FCC phase exists in the Co2Ni2CrV alloy (Ta-free); the FCC phase and the Laves phase exist in the Co2Ni2CrVTa Figure 3 alloy (0.1Ta). 0.1 The Co2Ni2CrVTa alloy (0.1Ta) contains the FCC phase and the Laves phase.

[0062] (2) Figure 4 In (a) is the SEM image of Co2Ni2CrV alloy, and only FCC phase can be seen; (b) is the SEM image of Co2Ni2CrVTa 0.1 alloy, and a small amount of Laves phase can be seen in addition to the FCC phase.

[0063] 2) Performance results

[0064] (1) The stress-strain curves are as Figure 6 shown. The ultimate tensile strengths of Co2Ni2CrV (Ta-free) and Co2Ni2CrVTa 0.1 (0.1Ta) alloys are ~ 571 MPa and ~ 622 MPa respectively, the yield strengths are ~ 305 MPa and ~ 402 MPa respectively, and the elongation rates are ~ 63.8 % and ~ 43.8 % respectively.

[0065] (2) The fitting curves of the ballistic penetration limit velocity are as Figure 7 shown. The ballistic limit velocities of Co2Ni2CrV and Co2Ni2CrVTa 0.1 alloys are ~ 407.8 m / s and ~ 417.7 m / s respectively.

[0066] (3) The energy absorption of the alloys at different penetration velocities is as Figure 8 shown. The energy absorptions of Co2Ni2CrV multi-component alloys at the penetration velocities of 450 m / s, 550 m / s, 650 m / s and 750 m / s are 132.4J, 140.3J, 158.4J and 177.1J respectively; the energy absorptions of Co2Ni2CrVTa 0.1 multi-component alloys at the penetration velocities of 450m / s, 550 m / s, 650 m / s and 750 m / s are 148.2J, 165.3J, 183.5J and 208.1J respectively.

[0067] Comparative Example 2

[0068] A multi-component alloy with the chemical formula Co2Ni2CrVTa is prepared by the same steps as in Example 1, and the components are composed according to the molar ratio of the subscripts in the chemical formula. 0.5 (37)

[0069] XRD and SEM characterizations are carried out on the Co2Ni2CrVTa 0.5 multi-component alloy.

[0070] The specific results are as follows:

[0071] The XRD results are as Figure 3 shown. Co2Ni2CrVTa0.5 In the (0.5Ta) multi-component alloy, the amount of Laves phase is further increased compared to Example 1 (0.3Ta). As shown in the SEM image in (d) below, the Laves phase appears in large chunks. Such large chunks of Laves are extremely harmful to the tensile and penetration properties. Therefore, no further characterization and testing were conducted on multi-component alloys with further increased Ta element content. Figure 4 In summary, in this example, by controlling the Ta element content, reticular micron-scale Laves phase and nano-sized L12 precipitation phase were obtained directionally, improving the tensile properties of the alloy while effectively enhancing the penetration properties of the alloy. In addition, the preparation method of this multi-component alloy is simple and easy to implement, and its excellent fluidity is suitable for industrial production, greatly expanding the application of multi-component alloys in the field of armor protection and providing a new tissue control strategy for the armor protection field.

[0072] The above are only examples of this application and are not used to limit this application. For those skilled in the art, various changes and modifications can be made to this application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this application shall be included within the scope of the claims of this application.

[0073] ​

Claims

1. A multi-component alloy for anti-penetration, characterized in that, The chemical formula of the alloy is Co2Ni2CrVTa 0.3 ; in the chemical formula, the subscripts are the molar ratios of the respective elements.

2. The preparation method of the anti-penetration multi-component alloy according to claim 1, characterized in that, The specific steps are as follows: 1) After evacuating the melting furnace, introduce an inert gas, and melt the Ti ingot 3 to 5 times. The arc duration for each melting is 60 s to 80 s, and the melting current is 240 A to 270 A; 2) Stack Ni, Co, Cr, V, and Ta in sequence from bottom to top in the melting furnace, melt 5 to 6 times, with a melting current of 240 A to 270 A, and the arc duration for each melting is 2 min to 3 min; then vacuum suction cast the melted metal solution to obtain the alloy; The molar ratios of the added Co, Ni, Cr, V, and Ta are 2:2:1:1:0.3 in sequence.

3. The preparation method of the anti-penetration multi-component alloy according to claim 2, wherein, The vacuum pumping means pumping to a vacuum degree of 9×10 -4 Pa to 1×10 -3 Pa.

4. The preparation method of the anti-penetration multi-component alloy according to claim 2, characterized in that, The introduction of the inert gas means introducing the inert gas to -0.03 MPa to -0.02 MPa.

5. The preparation method of the anti-penetration multi-component alloy according to claim 2, characterized in that The inert gas is argon.

6. The preparation method of the anti-penetration multi-component alloy according to claim 2, characterized in that Between two meltings, perform electromagnetic stirring 5 to 6 times, and the duration of each stirring is 1 min to 2 min.

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