CN115492886A - Three-dimensional honeycomb base unit with negative poisson's ratio characteristic, single-layer plate and structure - Google Patents

Three-dimensional honeycomb base unit with negative poisson's ratio characteristic, single-layer plate and structure Download PDF

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Publication number
CN115492886A
CN115492886A CN202211354288.3A CN202211354288A CN115492886A CN 115492886 A CN115492886 A CN 115492886A CN 202211354288 A CN202211354288 A CN 202211354288A CN 115492886 A CN115492886 A CN 115492886A
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rods
cell
vertical
basic
cell element
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赵炼恒
刘乐
赵彪
宋平
曾中林
金昶睿
丘伟兴
邓民
谢周州
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Guangzhou Track Maintenance Division Of Gsrc
Central South University
CREEC Chongqing Survey Design and Research Co Ltd
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Guangzhou Track Maintenance Division Of Gsrc
Central South University
CREEC Chongqing Survey Design and Research Co Ltd
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Priority to CN202211354288.3A priority Critical patent/CN115492886A/en
Publication of CN115492886A publication Critical patent/CN115492886A/en
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
    • F16F7/00—Vibration-dampers; Shock-absorbers
    • F16F7/12—Vibration-dampers; Shock-absorbers using plastic deformation of members
    • F16F7/121—Vibration-dampers; Shock-absorbers using plastic deformation of members the members having a cellular, e.g. honeycomb, structure
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
    • F16F7/00—Vibration-dampers; Shock-absorbers
    • F16F7/12—Vibration-dampers; Shock-absorbers using plastic deformation of members
    • F16F7/128—Vibration-dampers; Shock-absorbers using plastic deformation of members characterised by the members, e.g. a flat strap, yielding through stretching, pulling apart

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  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Laminated Bodies (AREA)

Abstract

The invention discloses a three-dimensional honeycomb basic unit with negative Poisson ratio characteristic, a single-layer plate and a structure, wherein the three-dimensional honeycomb basic unit comprises a unit frame, an inclined rod A and a supporting rod A, the unit frame comprises four basic cell units, the four basic cell three-dimensional honeycomb units are sequentially connected end to end through connecting rods to form a frame of the basic unit, the end points of vertical rods of all the basic cell units extend out of the inclined rod A and are converged to connecting points at the central axis inside the basic unit, the connecting points are connected with the supporting rod A extending to the outside of the basic unit, and the basic cell units are connected together through the inclined rods A to form a whole, so that the integrity of the basic unit is enhanced, and all parts of the basic unit can be coordinately deformed and uniformly stressed. The three-dimensional honeycomb single-layer plate is formed by connecting a plurality of three-dimensional honeycomb single-layer plates through a supporting rod A and a supporting rod B, is more suitable for manufacturing plate-type or block-type materials or devices, has good stability in structure, and has a negative Poisson ratio effect in three directions.

Description

Three-dimensional honeycomb base unit with negative poisson's ratio characteristic, single-layer plate and structure
Technical Field
The invention relates to the technical field of metamaterial structure design, in particular to a three-dimensional honeycomb basic unit, a three-dimensional honeycomb single-layer plate and a three-dimensional honeycomb structure with negative Poisson's ratio characteristics.
Background
The negative Poisson's ratio material and structure have different physical and mechanical properties from common materials, and can generate lateral expansion when being axially tensioned and lateral contraction when being axially compressed. The research results show that the negative Poisson ratio material has better performances in the aspects of energy absorption, vibration reduction, porous permeability, shearing resistance, fracture resistance and the like, and has wide application prospects in daily life and industrial production. For example, when a plate with a negative poisson's ratio characteristic is impacted, nearby materials can contract towards an impact point, so that more energy can be absorbed, the diffusion of impact energy is reduced, and the effects of energy absorption and vibration reduction are achieved. However, due to the insufficient and mature manufacturing and synthesis technology of the negative poisson ratio material, the types of the negative poisson ratio structures commonly used at present are few, and particularly, the three-dimensional negative poisson ratio structure is rare.
Disclosure of Invention
The present invention is directed to a three-dimensional honeycomb basic unit having a negative poisson's ratio characteristic, so as to solve the problems set forth in the background art.
In order to achieve the above purpose, the invention provides a three-dimensional honeycomb basic unit with negative poisson ratio characteristic, which comprises a unit frame, an inclined rod A and a supporting rod A, wherein the unit frame comprises four basic cells which are distributed in a rectangular shape, the basic cells are concave hexagonal cells, the concave hexagonal cells comprise two vertical cell rods which are symmetrical in parallel and four inclined cell rods with equal length, the top ends and the bottom ends of the two vertical cell rods are respectively connected through the two inclined cell rods which are connected, and the two inclined cell rods at the same end are both inclined inwards to the hexagon; the four basic cell elements are sequentially connected end to end through connecting rods; all connecting points of the cell element vertical rods and the cell element diagonal rods are connected with diagonal rods A, all diagonal rods A positioned at the top ends of the cell element vertical rods incline downwards and are finally connected to a first connecting point, and all diagonal rods A positioned at the bottom ends of the cell element vertical rods incline upwards and are finally connected to a second connecting point; the first and second connection points are both located on a longitudinal centerline of the unit frame; and the first connecting point, the second connecting point and each concave angle of the four basic cells are connected with a supporting rod A, and the supporting rods A and the cell vertical rods are arranged in parallel.
Further, the first connection point and the second connection point have the same horizontal height as the vertex of the upper concave angle and the vertex of the lower concave angle of the basic cell, respectively; the length of the support bars a is half the length of the cell vertical bars and all the support bars a extend from the connection points to the outside of the unit frame.
Further, the size of the three-dimensional honeycomb basic unit should satisfy the following relation:
β＝arctan(2tanθ)
Figure BDA0003920395020000021
in the formula, theta is the included angle between the vertical pole of the cell element and the diagonal pole of the cell element in the concave hexagonal cell element; beta is the included angle between the diagonal rod A and the vertical rod of the cell element; a is the length of the cell diagonal; l is the length of the connecting rod.
Furthermore, the included angle between the vertical cell element rod and the diagonal cell element rod is greater than or equal to 30 degrees and smaller than 90 degrees.
The invention also provides a three-dimensional honeycomb single-layer plate with a negative Poisson ratio characteristic, which comprises a single-layer plate framework, inclined rods B and supporting rods B, wherein the single-layer plate framework comprises a plurality of three-dimensional honeycomb basic units, each three-dimensional honeycomb basic units are arranged in a triangular form taking the connecting rods as sides, the three-dimensional honeycomb basic units which are arranged in the triangular form are spliced to form the single-layer plate framework, a plurality of hexagonal star areas are arranged in the single-layer plate framework, the end points of the cell element vertical rods of each basic cell element enclosing the hexagonal star areas are also connected with the inclined rods B, all the inclined rods B at the top ends of the cell element vertical rods incline downwards and are finally connected to a third connecting point, and all the inclined rods B at the bottom ends of the cell element vertical rods incline upwards and are finally connected to a fourth connecting point; the third connection point and the fourth connection point are both located on a longitudinal centerline of the hexagram region; and the third connecting point and the fourth connecting point are both connected with a supporting rod B, and the supporting rod B and the cell vertical rod are arranged in parallel.
Further, the length of the supporting rods B is half of the length of the vertical rods of the cell element, and all the supporting rods B extend from the connecting points to the outer side of the hexagram area.
Furthermore, the size of an included angle between the inclined rod B and the cell element vertical rod is equal to the size of an included angle between the inclined rod A and the cell element vertical rod.
The invention also provides a three-dimensional honeycomb structure with negative Poisson's ratio characteristic, which comprises at least two layers of the three-dimensional honeycomb single-layer plates, wherein the two adjacent layers of the three-dimensional honeycomb single-layer plates are connected through the supporting rod A and the supporting rod B.
Compared with the prior art, the invention has the following beneficial effects:
(1) The basic unit with the negative poisson ratio comprises a unit frame, an inclined rod A and a supporting rod A, wherein four basic cell elements are connected end to end through connecting rods to form the frame of the basic unit, the end points of the vertical rods of all the basic cell elements extend out of the inclined rod A and are converged to a connecting point at the central axis in the basic unit, the supporting rod A extending to the outside of the basic unit is connected at the connecting point, and the frame, the inclined rod A and the supporting rod A of the basic unit jointly form the basic unit of the negative poisson ratio three-dimensional honeycomb structure; the four basic cells are connected together to form a whole by the inclined rods A, so that the integrity of the basic unit is enhanced, and all parts of the basic unit can be coordinately deformed and uniformly stressed.
(2) According to the three-dimensional honeycomb single-layer plate with the negative Poisson's ratio, the plurality of basic units are connected together through the inclined rods B, the integrity and the stability of the three-dimensional honeycomb single-layer plate are enhanced, the stress performance of the three-dimensional honeycomb single-layer plate is improved, and the effect of coordinating deformation of the basic units is achieved.
(3) The three-dimensional honeycomb structure with the negative Poisson ratio characteristic is formed by connecting a plurality of three-dimensional honeycomb single-layer plates through the supporting rods A and the supporting rods B, is more suitable for manufacturing plate-type or block-type materials or devices, has good stability, and has the negative Poisson ratio effect in three directions.
In addition to the objects, features and advantages described above, other objects, features and advantages of the present invention are also provided. The present invention will be described in further detail below with reference to the drawings.
Drawings
The accompanying drawings, which are included to provide a further understanding of the embodiments of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the embodiments of the invention without limiting the embodiments of the invention. In the drawings:
FIG. 1 is a schematic diagram of the basic cell (concave hexagonal cell) of the present invention;
FIG. 2 is a schematic diagram of the structure of a basic unit in the present invention;
FIG. 3 is a top plan view of the base unit of FIG. 2;
FIG. 4 is a front view of the base unit of FIG. 2;
FIG. 5 is a schematic structural diagram of a single-layer plate with a three-dimensional honeycomb structure and a negative Poisson's ratio characteristic according to the invention;
FIG. 6 is a top view of the three-dimensional honeycomb single-layer panel of FIG. 5;
wherein: 1-a basic cell; 1.1-cell vertical bar; 1.2-cell diagonal; 2-a connecting rod; 3-a diagonal bar A; 4-support bar a, 5-diagonal bar B; 6-support bar B; m-three-dimensional honeycomb base unit; n-three-dimensional honeycomb single-layer plate.
Detailed Description
Embodiments of the invention will be described in detail below with reference to the drawings, but the invention can be implemented in many different ways, which are defined and covered by the claims.
Referring to fig. 1, the present embodiment provides a three-dimensional honeycomb basic unit with negative poisson's ratio, which includes a unit frame, an inclined rod a and a support rod a, and the specific structure is as follows:
the unit frame comprises four rectangular basic cells 1, and the basic cells 1 are concave hexagonal cells. As shown in fig. 1, the recessed hexagonal cell element includes two cell element vertical rods 1.1 and four cell element diagonal rods 1.2, the two cell element vertical rods 1.1 are equal in length and parallel to each other in the left-right direction, the four cell element diagonal rods 1.2 are equal in length, the four cell element diagonal rods are divided into two groups, the two cell element diagonal rods in each group are connected to form a recessed angle recessed towards the inner side of the hexagon, the two cell element diagonal rods in each group are connected to the upper and lower ends of the two cell element diagonal rods respectively after being connected to each other, and therefore the two recessed angles are oppositely arranged at the upper and lower ends of the recessed hexagonal cell element. Preferably, the included angle between the vertical cell rods 1.1 and the diagonal cell rods 1.2 of the concave hexagonal cells is more than or equal to 30 degrees and less than or equal to 90 degrees.
As shown in fig. 2 to 4, four basic cell elements 1 are sequentially connected end to end by connecting rods 2 to form a unit frame, specifically, the upper and lower ends of each cell element vertical rod 1.1 are respectively connected to the upper and lower ends of a cell element vertical rod close to the other basic cell element by one connecting rod 2, that is, two adjacent cell element vertical rods in different basic cell elements are connected by two connecting rods, the two ends of one connecting rod are respectively connected to the top ends of the two cell element vertical rods, and the two ends of the other connecting rod are respectively connected to the lower ends of the two cell element vertical rods. All the connecting points of the cell element vertical rod 1.1 and the cell element diagonal rod 1.2 are connected with diagonal rods A3, all the diagonal rods A3 connected with the top end of the cell element vertical rod incline downwards and are finally connected with a first connecting point, and all the diagonal rods A3 connected with the bottom end of the cell element vertical rod incline upwards and are finally connected with a second connecting point. These first and second connection points are located on the longitudinal centerline of the unit frame. And the first connecting point, the second connecting point and each concave angle of the four basic cells are respectively connected with a supporting rod A4, and the supporting rods A4 and the cell vertical rods are arranged in parallel. In the structural arrangement, the basic unit frame 1, the inclined rods A3 and the supporting rods A4 form a basic unit of a negative Poisson ratio three-dimensional honeycomb structure together, the inclined rods A3 connect the four basic cells 1 together to form a whole, the integrity of the basic unit is enhanced, and all parts of the basic unit can be coordinately deformed and uniformly stressed.
In one specific embodiment, the first connection point and the second connection point have the same horizontal height as the apex of the upper concave angle and the apex of the lower concave angle of the basic cell, respectively; the length of the support bars A4 is half the length of the cell vertical bars 1.1 and all the support bars A4 extend from the connection point to the outside of the unit frame.
In one specific embodiment, in order to achieve a coordinated deformation of the elements of the basic cell, the dimensions of the three-dimensional honeycomb basic cell should satisfy the following relationship:
β＝arctan(2tanθ)
Figure BDA0003920395020000041
in the formula, theta is the included angle between the vertical pole of the cell element and the diagonal pole of the cell element in the concave hexagonal cell element; beta is the included angle between the diagonal rod A and the vertical rod of the cell element; a is the length of the cell diagonal; l is the length of the connecting rod.
As shown in fig. 5 and fig. 6, this embodiment further provides a three-dimensional honeycomb single-layer plate with a negative poisson's ratio characteristic, which includes a single-layer plate skeleton, an inclined rod B and a supporting rod B, where the single-layer plate skeleton includes a plurality of three-dimensional honeycomb basic units M as described above, each three-dimensional honeycomb basic unit is arranged in a triangular form with the connecting rod 2 as a side to form a three-dimensional honeycomb basic unit group, and then a plurality of such three-dimensional honeycomb basic unit groups are finally spliced to form a single-layer plate skeleton, and the single-layer plate skeleton has a plurality of hexagram regions therein. The end points of the upper end and the lower end of each cell element vertical rod of each basic cell element enclosing a hexagram area are respectively connected with an inclined rod B5, all the inclined rods B positioned at the top ends of the cell element vertical rods incline downwards and are finally connected to a third connection point, and all the inclined rods B positioned at the bottom ends of the cell element vertical rods incline upwards and are finally connected to a fourth connection point; the third connection point and the fourth connection point are both located on a longitudinal centerline of the hexagram region. The third connecting point and the fourth connecting point are both connected with a supporting rod B6, and the supporting rod B and the cell vertical rod are arranged in parallel. In this arrangement, the length of the support rods B6 is half the length of the cell vertical rods 1.1, and all the support rods B extend from the respective connection points to the outside of the hexagram region. The base units are connected together by the inclined rods B, the integrity and stability of the three-dimensional honeycomb single-layer plate are enhanced, the stress performance of the three-dimensional honeycomb single-layer plate is improved, and the effect of coordinating deformation of the base units is achieved.
The embodiment also provides a three-dimensional honeycomb structure with a negative poisson's ratio characteristic, which comprises at least two three-dimensional honeycomb single-layer plates N, wherein the two adjacent three-dimensional honeycomb single-layer plates are connected through a supporting rod A4 and a supporting rod B6. In order to achieve a coordinated deformation of the individual components of the three-dimensional honeycomb structure, the component dimensions should satisfy the following conditions: 1) The support bar A4 and the support bar B6 have the same length; 2) The size of the included angle between the diagonal rod B5 and the cell element vertical rod 1.1 is equal to the size of the included angle between the diagonal rod A and the cell element vertical rod.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (8)

1. A three-dimensional honeycomb basic unit with a negative Poisson ratio characteristic is characterized by comprising a unit frame, inclined rods A and supporting rods A, wherein the unit frame comprises four basic cells which are distributed in a rectangular shape, the basic cells are concave hexagonal cells (1), the concave hexagonal cells comprise two vertical cell rods (1.1) which are symmetrical in parallel and four inclined cell rods (1.2) with the same length, the top ends and the bottom ends of the two vertical cell rods are respectively connected through the two inclined cell rods which are connected, and the two inclined cell rods at the same end are inclined inwards to the hexagon; the four basic cell elements are sequentially connected end to end through a connecting rod (2); all connecting points of the cell element vertical rods and the cell element diagonal rods are connected with diagonal rods A (3), all diagonal rods A positioned at the top ends of the cell element vertical rods incline downwards and are finally connected to a first connecting point, and all diagonal rods A positioned at the bottom ends of the cell element vertical rods incline upwards and are finally connected to a second connecting point; the first and second connection points are both located on a longitudinal centerline of the unit frame; and the first connecting point, the second connecting point and each concave angle of the four basic cells are connected with a supporting rod A (4), and the supporting rods A and the cell vertical rods are arranged in parallel.
2. The three-dimensional cellular base unit of claim 1, wherein the first connection point and the second connection point have the same horizontal height as the apex of the superior fillet and the apex of the inferior fillet of the base cell, respectively; the length of the support bars a is half the length of the cell vertical bars and all the support bars a extend from the connection points to the outside of the unit frame.
3. The three-dimensional cellular base unit of claim 1, wherein the dimensions of the three-dimensional cellular base unit satisfy the following relationship:
β＝arctan(2tanθ)
Figure FDA0003920395010000011
in the formula, theta is the included angle between the vertical pole of the cell element and the diagonal pole of the cell element in the concave hexagonal cell element; beta is the included angle between the diagonal rod A and the vertical rod of the cell element; a is the length of the cell diagonal; l is the length of the connecting rod.
4. The three-dimensional cellular base unit of claim 1, wherein the cell vertical bars and the cell diagonal bars are at an angle of greater than or equal to 30 ° and less than 90 °.
5. A three-dimensional honeycomb single-layer board with negative poisson's ratio characteristic, which is characterized in that the board comprises a single-layer board framework, inclined rods B and supporting rods B, the single-layer board framework comprises a plurality of three-dimensional honeycomb basic units (M) according to any one of claims 1-4, every three-dimensional honeycomb basic units are arranged in a triangular form with the connecting rods (2) as sides and are spliced to form the single-layer board framework, the single-layer board framework is internally provided with a plurality of hexagram areas, inclined rods B (5) are further connected to the end points of cell element vertical rods of each basic cell element enclosing the hexagram areas, all the inclined rods B at the top ends of the cell element vertical rods are inclined downwards and are connected to a third connecting point finally, and all the inclined rods B at the bottom ends of the cell element vertical rods are inclined upwards and are connected to a fourth connecting point finally; the third connection point and the fourth connection point are both located on a longitudinal centerline of the hexagram region; and the third connecting point and the fourth connecting point are both connected with a supporting rod B (6), and the supporting rod B and the cell vertical rod are arranged in parallel.
6. The three-dimensional honeycomb single-layer board according to claim 5, wherein the length of the supporting rods B is half of the length of the cell vertical rods, and all the supporting rods B extend from the connecting points to the outside of the hexagonally pointed area.
7. The three-dimensional honeycomb single-layer board according to claim 5, wherein the angle between the diagonal member B and the vertical member of the cell is equal to the angle between the diagonal member A and the vertical member of the cell.
8. Three-dimensional cellular structure with negative poisson's ratio characteristics, characterised in that it comprises at least two three-dimensional cellular single-layer panels (N) according to any one of claims 5 to 7, adjacent two of which are connected by means of said supporting bars a and B.
CN202211354288.3A 2022-11-01 2022-11-01 Three-dimensional honeycomb base unit with negative poisson's ratio characteristic, single-layer plate and structure Pending CN115492886A (en)

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