Shape memory polymer filled multistable negative Poisson's ratio structure shock absorber

Abstract

The invention relates to the technical field of damping structures, and discloses a shape memory polymer filled multistable negative Poisson's ratio structure damper which comprises a plurality of multistable structure shells which are of a bilateral symmetry structure and made of negative Poisson's ratio materials, cavities are defined in the multistable structure shells, and the multistable structure shells are arranged in an array mode; the shape memory polymer is arranged in the cavity, and the shape memory polymer is made of a shape memory negative Poisson's ratio polymer. The cavity is formed in the multi-stable-state structure shell, the cavity is filled with the shape memory polymer made of the shape memory negative Poisson's ratio polymer, the overall strength and rigidity of the structure can be improved while the negative Poisson's ratio characteristic is kept, and therefore the application range of the negative Poisson's ratio material in the vibration reduction field is expanded. The addition of the shape memory polymer is beneficial to improving the deformation capacity of the whole structure during bearing, and meanwhile, the structure can be recovered to the initial shape after being unloaded based on the recovery capacity of the shape memory polymer.

Description

Technical Field

[0001] This invention relates to the field of vibration reduction structure technology, and in particular to a shape memory polymer-filled multistable negative Poisson's ratio structure vibration damper. Background Technology

[0002] Negative Poisson's ratio materials, as a novel type of functional material, exhibit a negative Poisson's ratio effect under load. This means that when the material undergoes tensile deformation, it expands laterally in the direction perpendicular to the load; conversely, when the material undergoes compressive deformation, it contracts laterally in the direction perpendicular to the load. This tensile-expansion characteristic endows negative Poisson's ratio materials with unique mechanical properties, exhibiting significantly better shear resistance than tensile-compressive resistance. Therefore, negative Poisson's ratio structural materials are commonly used as energy-absorbing elements in shock absorbers.

[0003] However, the application of negative Poisson's ratio materials in shock absorbers has the following technical drawbacks:

[0004] 1. Compared with solid materials of the same mass, negative Poisson's ratio materials have lower stiffness and strength, thus limiting their application range.

[0005] 2. Negative Poisson's ratio materials have insufficient deformation capacity under load and poor shape recovery ability after unloading.

[0006] Therefore, how to provide a negative Poisson's ratio shock absorber with high structural strength and good deformation capacity is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0007] The purpose of this invention is to provide a shape memory polymer-filled multistable negative Poisson's ratio structure vibration damper to solve the problems existing in the prior art.

[0008] To achieve the above objectives, the present invention provides a shape memory polymer-filled multistable negative Poisson's ratio structure vibration damper, comprising:

[0009] Multiple multistable structural shells, with a bilaterally symmetrical structure, are made of a negative Poisson's ratio material and have internal cavities defined within them. The multiple multistable structural shells are arranged in an array.

[0010] A shape memory polymer is disposed within the cavity, and the shape memory polymer is made of a shape memory negative Poisson's ratio polymer.

[0011] Furthermore, the multistable structure shell includes:

[0012] roof;

[0013] A bistable curved beam is disposed below the top plate and connected to the top plate via a connecting plate. The bistable curved beam has a left-right symmetrical structure, and the connecting plate is located on the line of symmetry.

[0014] A base is disposed below the bistable curved beam, and a cavity is formed between the bistable curved beam and the base.

[0015] Furthermore, the top plate has a thickness of 4t, the base consists of a bottom plate and side plates, the bottom plate has a thickness of 4t, the side plates have a thickness of 3t, the bistable curved beam has a thickness of t, and the connecting plate has a thickness of t.

[0016] Furthermore, t = 0.4 mm.

[0017] Furthermore, the planar curve of the bistable curved beam conforms to the following function:

[0018]

[0019] Establish a rectangular coordinate system with the line connecting the two endpoints of the bistable curved beam as the x-axis and the line of symmetry as the y-axis; in the above functions... is the height of the bistable curved beam along the y-axis, x is the span of the bistable curved beam along the x-axis, h is the mid-span height of the bistable curved beam, and L is the span of the bistable curved beam.

[0020] Furthermore, h is 4 mm and L is 40 mm.

[0021] Furthermore, the multistable structure shell is manufactured using selective laser melting, with Ti6Al4V powder as the base material.

[0022] Furthermore, the shape memory polymer is a shape memory negative Poisson's ratio polyurethane foam.

[0023] The present invention discloses the following technical effects:

[0024] 1. The multistable structure has a cavity inside the shell, which is filled with a shape memory polymer made of negative Poisson's ratio polymer. This can improve the overall strength and stiffness of the structure while maintaining the negative Poisson's ratio characteristics, thereby expanding the application range of negative Poisson's ratio materials in the field of vibration reduction.

[0025] 2. The addition of shape memory polymers helps to improve the overall deformation capacity of the structure under load, and at the same time, the recovery capacity of shape memory polymers can enable the structure to return to its initial shape after unloading.

[0026] 3. Compared with conventional shape memory energy-absorbing materials, the present invention can further compress and stretch the shape memory polymer during loading and unloading by utilizing the negative Poisson's ratio structure, thereby improving the overall buffering energy absorption characteristics of the structure. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a schematic diagram illustrating the interaction between the multistable structure shell and the shape memory polymer.

[0029] Figure 2 This is a schematic diagram of the multi-stable structure shell;

[0030] Figure 3 Schematic diagram of a vibration damper with a multistable negative Poisson's ratio structure filled with shape memory polymer;

[0031] The components include: 1. Multistable structural shell; 2. Shape memory polymer; 3. Top plate; 4. Base; 5. Connecting plate; and 6. Bistable curved beam. Detailed Implementation

[0032] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] Those skilled in the art will understand that the term "comprising" as used in this application means the presence of the stated features, integers, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. It should be understood that when we say an element is "connected" or "coupled" to another element, it can be directly connected or coupled to the other element, or there may be intermediate elements present. Furthermore, "connected" or "coupled" as used herein can include wireless connections or wireless coupling. The term "and / or" as used herein includes all or any unit and all combinations of one or more associated listed items.

[0034] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0035] like Figures 1 to 3 As shown, an embodiment of the present invention provides a shape memory polymer-filled multistable negative Poisson's ratio structure vibration damper, comprising:

[0036] Multiple multistable structural shells 1 are bilaterally symmetrical structures made of negative Poisson's ratio material, with cavities defined inside them, and the multiple multistable structural shells 1 are arranged in an array.

[0037] Shape memory polymer 2 is disposed in the cavity. Shape memory polymer 2 is made of shape memory negative Poisson's ratio polymer.

[0038] In this embodiment, the multistable structure shell 1 includes:

[0039] Top plate 3;

[0040] The bistable curved beam 6 is located below the top plate 3 and connected to the top plate 3 via the connecting plate 5. The bistable curved beam 6 has a left-right symmetrical structure, and the connecting plate 5 is located on the line of symmetry.

[0041] The base 4 is located below the bistable curved beam 6, and the bistable curved beam 6 and the base 4 form a cavity.

[0042] In this embodiment, the thickness of the top plate 3 is 4t, the base 4 is composed of a bottom plate and a side plate, the thickness of the bottom plate is 4t, the thickness of the side plate is 3t, the thickness of the bistable curved beam 6 is t, and the thickness of the connecting plate 5 is t.

[0043] In this embodiment, t = 0.4 mm.

[0044] In this embodiment, the planar curve of the bistable curved beam 6 conforms to the following function:

[0045]

[0046] A rectangular coordinate system is established with the line connecting the two endpoints of the bistable curved beam 6 as the x-axis and the line of symmetry as the y-axis; in the above functions... is the height of the bistable curved beam 6 along the y-axis, x is the span of the bistable curved beam 6 along the x-axis, h is the mid-span height of the bistable curved beam 6, and L is the span of the bistable curved beam 6.

[0047] In this embodiment, h is 4 mm and L is 40 mm.

[0048] In this embodiment, the multistable structure shell 1 is manufactured by selective laser melting, and the base material is Ti6Al4V powder.

[0049] In this embodiment, the shape memory polymer 2 is a shape memory negative Poisson's ratio polyurethane foam.

[0050] The specific work process is as follows:

[0051] When the structure is stretched longitudinally, the distance between the left and right sides of the cavity will increase; when the structure is compressed longitudinally, the distance between the left and right sides of the cavity will decrease, and the shape memory polymer 2 inside the cavity will deform accordingly. In addition, when the shape memory polymer 2 is subjected to force, its elasticity and viscosity will play a role at the same time, which can effectively dissipate the energy of the vibration system.

[0052] Deformation capacity tests were conducted on shape memory polymers 2 of the same shape, with one set placed inside the cavity and the other outside. The results showed that the shape memory polymer 2 inside the cavity exhibited greater lateral deformation, demonstrating that the negative Poisson's ratio structure can further compress and stretch the shape memory polymer 2 during loading and unloading, thereby improving the overall energy absorption and buffering characteristics of the structure. Experiments show that the shape memory polymer-filled multistable negative Poisson's ratio structure vibration damper disclosed in this embodiment, compared to traditional negative Poisson's ratio vibration dampers, has improved strength, stiffness, and elongation by 35.2%, 40.3%, and 36.1%, respectively.

[0053] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0054] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0055] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0056] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A shape memory polymer-filled multistable negative Poisson's ratio structure vibration damper, characterized in that, include: Multiple multistable structural shells (1) are left-right symmetrical structures made of negative Poisson's ratio material, with cavities defined inside. The multiple multistable structural shells (1) are arranged in an array. A shape memory polymer (2) is disposed in the cavity, and the shape memory polymer (2) is made of a shape memory negative Poisson's ratio polymer.

2. The shape memory polymer-filled multistable negative Poisson's ratio structure vibration damper according to claim 1, characterized in that, The multistable structure shell (1) includes: Top plate (3); A bistable curved beam (6) is set below the top plate (3) and connected to the top plate (3) through a connecting plate (5). The bistable curved beam (6) has a left-right symmetrical structure, and the connecting plate (5) is located on the line of symmetry. The base (4) is located below the bistable curved beam (6), and the bistable curved beam (6) and the base (4) form a cavity.

3. A shape memory polymer-filled multistable negative Poisson's ratio structure vibration damper according to claim 2, characterized in that, The top plate (3) has a thickness of 4t, the base (4) consists of a bottom plate and a side plate, the bottom plate has a thickness of 4t, the side plate has a thickness of 3t, the bistable curved beam (6) has a thickness of t, and the connecting plate (5) has a thickness of t.

4. A shape memory polymer-filled multistable negative Poisson's ratio structure vibration damper according to claim 3, characterized in that, t=0.4 mm.

5. A shape memory polymer-filled multistable negative Poisson's ratio structure vibration damper according to claim 2, characterized in that, The planar curve of the bistable curved beam (6) conforms to the following function: A rectangular coordinate system is established with the line connecting the two endpoints of the bistable curved beam (6) as the x-axis and the line of symmetry as the y-axis; in the above functions, is the height of the bistable curved beam (6) along the y-axis, x is the span of the bistable curved beam (6) along the x-axis, h is the mid-span height of the bistable curved beam (6), and L is the span of the bistable curved beam (6).

6. A shape memory polymer-filled multistable negative Poisson's ratio structure vibration damper according to claim 5, characterized in that, h is 4 mm and L is 40 mm.

7. A shape memory polymer-filled multistable negative Poisson's ratio structure vibration damper according to claim 1, characterized in that, The multi-stable structure shell (1) is manufactured by selective laser melting, and the base material is Ti6Al4V powder.

8. A shape memory polymer-filled multistable negative Poisson's ratio structure vibration damper according to claim 1, characterized in that, The shape memory polymer (2) is a shape memory negative Poisson's ratio polyurethane foam.

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