Bionic vein section four-stage reinforced structure

Abstract

The invention provides a bionic vein section four-stage reinforced structure which comprises four stages of reinforcing ribs, the section of each stage of reinforcing rib is in a semi-dome and rectangular vein-imitating section shape, and the four stages of reinforcing ribs comprise a first-stage reinforcing rib, a second-stage reinforcing rib, a third-stage reinforcing rib and a fourth-stage reinforcing rib; the first-stage reinforcing ribs are arranged at intervals of 25mm in the width direction; the second-stage reinforcing ribs are arranged at intervals of 25mm in the length direction and are perpendicular to the first-stage reinforcing ribs; the third-stage reinforcing ribs are arranged in intervals of the first-stage reinforcing ribs at equal intervals, are parallel to the first-stage reinforcing ribs and are perpendicular to the second-stage reinforcing ribs; and the fourth-stage reinforcing ribs are arranged in the intervals of the second-stage reinforcing ribs at equal intervals, are parallel to the second-stage reinforcing ribs and are perpendicular to the first-stage reinforcing ribs. A bionic vein four-stage stiffened plate structure is constructed by combining a traditional stiffened plate structure with vein section grading, so that the stiffened plate structure fully utilizes the bearing and deformation energy absorption of reinforcing ribs when facing the impact load effect.

Description

Technical Field

[0001] The invention belongs to a reinforced plate structure, and in particular relates to a four-level reinforced structure of a bionic leaf vein cross section. Background Art

[0002] Due to the stringent quality and protective performance requirements of weapons, equipment, ships, and aerospace vehicles, improving their protective capabilities requires comprehensive consideration of lightweighting both protective materials and structures. Reinforced structures are widely used in both military and civilian applications due to their economical and structural advantages. Reinforced plate structures are widely used in armor plates, surface and underwater vessels, offshore structures, box girders, bridge decks, oil tanks, and aircraft structures. According to statistics, various types of reinforced plates can account for over 35% of large hull structural components, playing a crucial role in lightweighting hull structures. In recent years, with companies placing increasing emphasis on product lightweighting, the scope and level of application of reinforcements have significantly increased. Considering the need to ensure structural reliability and stability, reinforced structures are considered more effective than unreinforced plates in reducing weight and increasing load-bearing capacity. Traditional reinforcements are heavy, bulky, and inflexible. Their uniform cross-sectional dimensions throughout the entire structure result in significant material waste in low-load-bearing areas, making it difficult to reduce the overall weight of the structure. Furthermore, a uniform orthogonal arrangement precludes targeted placement. Therefore, how to improve the energy absorption capacity and impact resistance of the reinforced rib structure under extreme loads has become a key issue that needs to be solved urgently. Summary of the Invention

[0003] The purpose of the present invention is to solve the problems of energy absorption capacity and impact resistance of traditional reinforcement rib structures under fragment impact load.

[0004] To achieve the above-mentioned object, the present invention provides a four-level reinforced plate structure with a bionic leaf vein cross section, comprising four levels of reinforcing ribs scaled in a width ratio of 6:3:2:1, wherein the cross section of each level of reinforcing ribs is a semi-dome or a semi-dome plus a rectangle imitating the cross section of a leaf vein, and the four levels of reinforcing ribs include first-level reinforcing ribs, second-level reinforcing ribs, third-level reinforcing ribs, and fourth-level reinforcing ribs; The first-level reinforcement ribs are arranged at intervals of 25 mm along the width direction; The second-level reinforcement ribs are arranged at intervals of 25mm along the length direction and are perpendicular to the first-level reinforcement ribs; The third-level reinforcement ribs are arranged at equal intervals within the first-level reinforcement ribs, parallel to the first-level reinforcement ribs, and perpendicular to the second-level reinforcement ribs; The fourth-level reinforcement ribs are arranged at equal intervals within the intervals of the second-level reinforcement ribs, are parallel to the second-level reinforcement ribs, and are perpendicular to the first-level reinforcement ribs.

[0005] Furthermore, the cross section of the first-level reinforcement ribs is a semi-dome-like leaf vein cross section, and the cross sections of the second-level reinforcement ribs, the third-level reinforcement ribs, and the fourth-level reinforcement ribs are all semi-dome-plus-rectangular leaf vein cross sections.

[0006] Furthermore, the overall height of the cross-sections of the first-level reinforcing ribs, the second-level reinforcing ribs, the third-level reinforcing ribs, and the fourth-level reinforcing ribs is 2 mm, and the radii of the semicircles of the cross-sections are 3 mm, 1.5 mm, 1 mm, and 0.5 mm, respectively.

[0007] Furthermore, the widths of the first-level reinforcing ribs, the second-level reinforcing ribs, the third-level reinforcing ribs, and the fourth-level reinforcing ribs are 6 mm, 3 mm, 2 mm, and 1 mm, respectively.

[0008] Furthermore, the four-level reinforcement structure is prepared by 3D printing technology, and the printing substrate can be Ti6Al4V titanium alloy.

[0009] Furthermore, the equivalent surface density of the four-level reinforced structure of the bionic leaf vein section is 1.2347 g / cm 2 .

[0010] This structure constructs a four-level reinforced structure with a bionic leaf vein section by combining an irregular cross-section load-bearing structure with a traditional reinforced structure and a bionic leaf vein graded cross-section. This enables the traditional reinforced structure to efficiently utilize the mass per unit area when facing an impact, fully utilize the stiffness enhancement and deformation energy absorption of the reinforcement, and improve the unit surface density stiffness and energy absorption efficiency of the traditional reinforcement structure.

[0011] Beneficial effects: (1) The four-level reinforced plate structure with a bionic leaf vein cross section of the present application has significant advantages in mechanical properties. By changing the original ribs with uniform cross-sectional shape and size into ribs with localized thickening, the stress distribution of the reinforced structure under extreme loads is effectively optimized, and the compressive strength and energy absorption efficiency of key areas of the structure are improved. The characteristics of the reinforced plate-shell structure enable the back plate and ribs to cooperate in exhibiting a deformation mechanism different from that of a simple homogeneous plate when subjected to stress. For example, when facing large overall deformation, the partial stretching and necking of the back ribs constrains the overall deformation, delaying the failure process and improving the stability of the structure.

[0012] (2) The graded rib distribution not only improves the protective support effect of key areas but also reduces the overall material consumption, reduces the excess mass caused by the large and bulky mass of traditional reinforcement ribs, and further enhances the economic efficiency of the same protection. The customizability brought by the graded rib design allows the mechanical properties of different areas and directions to be precisely controlled, which is particularly important in complex environments where both stiffness and energy absorption need to be taken into account. Through this design, the utilization rate of materials is improved, and a combination of lightweight and high performance is achieved, especially under dynamic impact or collision conditions. The four-level reinforcement structure of the bionic leaf vein cross section can reduce the impact of the impact through the cross configuration of the larger ribs and the smaller ribs to disperse stress waves and fracture to absorb energy, thereby significantly improving the impact resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 a is a schematic diagram of the four-level reinforcement structure of the bionic leaf vein cross section of the present invention; Figure 1 b is a side view of the four-level reinforcement structure of the bionic leaf vein cross section of the present invention; Figure 1 c is a left view of the four-level reinforcement structure of the bionic leaf vein cross section of the present invention; Figure 1 d is a top view of the four-level reinforcement structure of the bionic leaf vein cross section of the present invention; Figure 2 This is a physical picture of the four-level reinforcement structure of the bionic leaf vein cross section; Figure 3 This is a schematic diagram of the four-level reinforcement plane structure of the bionic leaf vein section; Figure 4 A schematic cross-sectional view of a reinforcement bar of a reinforced structure provided by the present invention; Figure 5 This is a schematic diagram of a traditional fixed-section reinforced plane structure; Figure 6 This is a physical diagram of a traditional fixed-section reinforced plane structure; Figure 7 a is a schematic diagram of the simulation of the protection effect of the four-level reinforcement structure of the bionic leaf vein section against fragment impact; Figure 7 b is a simulation diagram of the protection effect of the traditional fixed-section reinforced structure against fragment impact; Figure 8 The stress wave transmission mode of the four-level reinforced structure of the bionic leaf vein section.

[0014] Figure numbers: 1-first level reinforcement rib, 2-second level reinforcement rib, 3-third level reinforcement rib, 4-fourth level reinforcement rib. DETAILED DESCRIPTION

[0015] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0016] The application principle of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0017] Example 1: like Figure 1 a- Figure 4 As shown, a four-level reinforced structure of a bionic leaf vein cross-section includes four levels of reinforcing ribs. The key cross-sectional dimensions of the reinforcing ribs of each level are scaled by the dimensions of the previous level. Starting from the largest level, the structure is divided into four levels of reinforcing ribs in a ratio of 6:3:2:1. Through the four levels of reinforcing ribs of different specifications, a leaf vein-like graded reinforcement system is formed. Figure 5 and Figure 6 This is a schematic diagram of the traditional fixed-section reinforced plane structure used for comparison. The surface density of the two reinforced structures is close, and the error is less than one ten-thousandth.

[0018] Bionic leaf vein cross-section with four-level reinforcement intersection structure: The maximum width of the first-level reinforcement ribs is 6mm, and the cross-section is a semicircular leaf vein-like cross-section shape. The overall height of the cross-section is 2mm, and the radius of the semicircle is 3mm. Multiple first-level reinforcement ribs are arranged at intervals of 25mm along the width direction.

[0019] The maximum width of the second-level reinforcement ribs is 3mm, and the cross-section is a semi-dome plus a rectangular leaf vein-like cross-section. The overall height of the cross-section is 2mm, and the radius of the semicircle is 1.5mm. Multiple second-level reinforcement ribs are arranged at intervals of 25mm along the length direction and are perpendicular to the first-level reinforcement ribs to form an overall structural frame.

[0020] The maximum width of the third-level reinforcement ribs is 2mm, and the cross-section is a semi-dome plus a rectangular leaf vein-like cross-section. The overall height of the cross-section is 2mm, and the radius of the semicircle is 1mm. Multiple third-level reinforcement ribs are arranged at equal intervals in the gaps between the first-level reinforcement ribs, parallel to the first-level reinforcement ribs, and perpendicular to the second-level reinforcement ribs.

[0021] The maximum width of the fourth-level reinforcement ribs is 1mm, and the cross-section is a semi-dome plus a rectangular leaf vein-like cross-section. The overall height of the cross-section is 2mm, and the radius of the semicircle is 0.5mm. Multiple fourth-level reinforcement ribs are arranged at equal intervals in the gaps between the second-level reinforcement ribs, parallel to the second-level reinforcement ribs, and perpendicular to the first-level reinforcement ribs.

[0022] The cross-sectional shapes of the first, second, third, and fourth-level reinforcement ribs are all semi-dome or semi-dome plus rectangle, imitating the cross-sectional shape of leaf veins. The overall height of each level of reinforcement rib is 2mm, and the back plate thickness is 2mm. Based on the above conditions, the equivalent surface density of the four-level reinforcement structure imitating the cross-sectional shape of leaf veins is 1.2347g / cm 2 The equivalent surface density of the traditional fixed-section reinforced structure is 1.2437 g / cm 2 .

[0023] The above-mentioned four-level stiffened plate and shell structure is prepared by 3D printing technology, and the printing base material is Ti6Al4V titanium alloy.

[0024] Under the action of impact load, the four-level reinforced structure of the bionic leaf vein section transmits stress waves and deforms through the large and small ribs of the back plate to dissipate the energy during the impact load loading process; the impact resistance indicators used to characterize the four-level reinforced plate structure of the bionic leaf vein section under the impact of flying fragments include the maximum penetration velocity, which can be obtained through numerical simulation calculations.

[0025] Example 2: The above-mentioned four-level reinforced structure of the bionic leaf vein section includes four levels of reinforcing ribs. The key cross-sectional dimensions of the reinforcing ribs of each level are scaled by part of the dimensions of the previous level. From the largest level, they are divided into four levels of reinforcing ribs in the ratio of 6:3:2:1.

[0026] Please refer to Figures 7-8 ,Depend on Figure 7 a It can be seen that the intersection center of the first and second ribs of the four-level reinforced structure of the bionic leaf vein section is impacted by a cylindrical flat-head simulated projectile with a speed of 350m / s and a mass of 6.15g. The traditional fixed-section reinforced structure is also impacted by a cylindrical flat-head simulated projectile under the same working condition at the intersection center of two orthogonally arranged ribs. Under the same impact conditions, the four-level reinforced structure of the bionic leaf vein section has a relatively rounded rib section and connection. While dispersing the impact stress wave, it effectively avoids the local collapse caused by stress concentration and the local collapse and adiabatic shear of the TC4 printed titanium alloy plate, and thereby strengthens the local impact resistance of the reinforced plate and shell structure. In the end, its overall damage effect presents a local large deformation failure mode, and the maximum displacement of the rib center is 9.12mm. However, in the face of this impact condition, the traditional fixed-section reinforced structure is Figure 7b It can be seen that the evenly arranged fixed-section ribs cause a large amount of stress concentration due to their own rectangular cross-section, and under the condition of consistent surface density, the specific stiffness and specific strength provided by the rectangular cross-section ribs to the overall stiffened plate-shell structure are not as good as the bionic leaf vein cross-section combining semicircle and rectangle. The above reasons lead to the rapid stress concentration and adiabatic shear phenomenon of the TC4 titanium alloy plate after being impacted by the fragment simulation projectile. The fragment simulation projectile punches out a circular punch hole in the shape of the projectile body on the stiffened plate, and finally its overall damage effect presents a shear fracture failure mode. The speed of the fragment simulation projectile after hitting the target is 57.3m / s.

[0027] After multiple simulation calculations, the maximum penetration speed of the four-level reinforced plate structure with bionic leaf vein cross-section under the above conditions is about 380m / s under the impact of flying fragments, while the maximum penetration speed of the traditional fixed-section reinforced structure under the same working conditions is about 340m / s. The protective effect of the former is improved by 11.76% compared with the latter.

[0028] Compared with the traditional fixed-section reinforced structure, the bionic leaf vein section four-level reinforced structure is stronger in specific stiffness, specific strength and impact resistance than the traditional fixed-section reinforced structure.

[0029] In summary, the present invention can improve the energy absorption performance of the traditional fixed-section reinforced structure and greatly enhance the impact resistance of the structure.

[0030] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A four-level reinforcement structure of a bionic leaf vein cross section, characterized in that: The four-level reinforcement ribs are scaled in a width ratio of 6:3:2:

1. The cross section of each level of reinforcement ribs is a semi-dome or a semi-dome plus a rectangle imitating a leaf vein cross section. The four-level reinforcement ribs include first-level reinforcement ribs, second-level reinforcement ribs, third-level reinforcement ribs and fourth-level reinforcement ribs. The first-level reinforcement ribs are arranged at intervals of 25 mm along the width direction; The second-level reinforcement ribs are arranged at intervals of 25mm along the length direction and are perpendicular to the first-level reinforcement ribs; The third-level reinforcement ribs are arranged at equal intervals within the first-level reinforcement ribs, parallel to the first-level reinforcement ribs, and perpendicular to the second-level reinforcement ribs; The fourth-level reinforcement ribs are arranged at equal intervals within the intervals of the second-level reinforcement ribs, are parallel to the second-level reinforcement ribs, and are perpendicular to the first-level reinforcement ribs.

2. The bionic leaf vein cross-section four-level reinforcement structure according to claim 1, characterized in that: The cross section of the first-level reinforcement ribs is a semi-dome-like leaf vein cross section shape, and the cross sections of the second-level reinforcement ribs, the third-level reinforcement ribs, and the fourth-level reinforcement ribs are all semi-dome-plus-rectangular leaf vein cross sections.

3. The bionic leaf vein cross-section four-level reinforcement structure according to claim 1, characterized in that: The overall height of the cross-sections of the first-level reinforcement ribs, the second-level reinforcement ribs, the third-level reinforcement ribs, and the fourth-level reinforcement ribs is 2 mm, and the radii of the semicircles of the cross-sections are 3 mm, 1.5 mm, 1 mm, and 0.5 mm, respectively.

4. The bionic leaf vein cross-section four-level reinforcement structure according to claim 2, characterized in that: The widths of the first-level reinforcement ribs, the second-level reinforcement ribs, the third-level reinforcement ribs, and the fourth-level reinforcement ribs are 6mm, 3mm, 2mm, and 1mm, respectively.

5. The bionic leaf vein cross-section four-level reinforcement structure according to claim 1, characterized in that: The four-level reinforced structure is prepared by 3D printing technology, and the printing base material can be Ti6Al4V titanium alloy.

6. The bionic leaf vein cross-section four-level reinforcement structure according to claim 1, characterized in that: The equivalent surface density of the four-level reinforced structure of the bionic leaf vein section is 1.2347 g / cm 2 .

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