CN211315750U - Truss structure with adjustable mechanical property - Google Patents
Truss structure with adjustable mechanical property Download PDFInfo
- Publication number
- CN211315750U CN211315750U CN201921550618.XU CN201921550618U CN211315750U CN 211315750 U CN211315750 U CN 211315750U CN 201921550618 U CN201921550618 U CN 201921550618U CN 211315750 U CN211315750 U CN 211315750U
- Authority
- CN
- China
- Prior art keywords
- dimensional
- truss structure
- units
- model
- mechanical properties
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Prostheses (AREA)
Abstract
The embodiment of the utility model discloses mechanical properties adjustable truss structure, include the two-dimensional frame unit that forms by the bracing piece mirror image connection combination of a plurality of "Z" font structures, the bracing piece of "Z" font structure has the same angle of design. Adopt the utility model discloses, realized the mechanical properties that adjusts and control truss structure through the geometric parameter of adjustment design model, the utility model discloses can also design and make the special application material that has very high porosity and have negative poisson's ratio characteristic, but wide application in fields such as medical artificial bone structure, space flight and aviation.
Description
Technical Field
The utility model relates to a mechanics frame construction especially relates to a mechanical properties adjustable truss structure.
Background
In the prior art, the mechanical structure related to the weight reduction is mainly a porous structure, and for a method for preparing a porous ceramic material, a foaming method, a template method, a pore-forming agent method and the like are generally used. The pore diameter of the pores of the porous scaffold obtained by the foaming method is difficult to control, and the connectivity among the pores is low. The pore-forming agent method is simple and easy to operate, and is a common method for preparing the porous ceramic material. The pore-forming agent method is to mix the pore-forming agent and slurry to form a stent model, and then remove the pore-forming agent in a dissolving or calcining way, thereby obtaining the porous material. The commonly used pore-forming agent mainly comprises salt particles (including high-temperature decomposable salts such as ammonium carbonate, ammonium bicarbonate, ammonium chloride and the like), starch particles and the like, when the number of pores of the obtained structure is too large, the mechanical strength of the material is reduced, and the risk of breakage exists, and when the number of pores is too small, the material is unevenly distributed, and the high porosity cannot be achieved. In addition, the mechanical properties of the cellular structures and truss structures in the prior art are generally difficult to adjust or cannot be adjusted as desired, and thus, the cellular structures and truss structures cannot be suitable for various applications.
SUMMERY OF THE UTILITY MODEL
The embodiment of the utility model provides a technical problem that will solve lies in, provides a mechanical properties adjustable truss structure and manufacturing method thereof. The porosity of the truss structure can be greatly improved, and a lightweight high-strength structure is achieved.
In order to solve the technical problem, the embodiment of the utility model provides a mechanical properties adjustable truss structure, include the two-dimensional frame unit that forms by the bracing piece mirror image connection combination of a plurality of "Z" font structures, the bracing piece of "Z" font structure has the same angle of design.
Furthermore, the Z-shaped structure is composed of three sections of the supporting rods with equal length.
The design angle is acute, which can produce a negative poisson's ratio effect.
Further, the three-dimensional structure unit is a hexahedral structure, and the two-dimensional frame unit forms the hexahedral structure.
Further, adjacent two-dimensional frame cells in the hexahedral structure have a shared edge.
Furthermore, a plurality of three-dimensional structure units are included, and the same two-dimensional frame unit is used between adjacent three-dimensional structure units.
The three-dimensional structure unit is composed of three two-dimensional frame units, and a concentric and orthogonal connection relationship is formed between every two three two-dimensional frame units.
The three-dimensional structure unit comprises a plurality of three-dimensional structure units, and the support rods of two-dimensional frame units which are orthogonal and are identical are arranged between the adjacent three-dimensional structure units.
Implement the embodiment of the utility model provides a, following beneficial effect has: the utility model discloses have negative poisson ratio characteristic and higher porosity, realized simultaneously that the geometric parameter through adjustment design model adjusts and control the mechanical properties of truss structure, the utility model discloses can design and make the special application material that has very high porosity and have negative poisson ratio characteristic, but wide application in fields such as medical artificial bone structure, space flight aviation.
Drawings
Fig. 1 is a schematic view of a single three-dimensional structure in a first embodiment of the invention;
fig. 2 is a schematic structural view of a plurality of three-dimensional structures according to a first embodiment of the present invention;
fig. 3 is a schematic structural diagram of the first embodiment of the present invention for testing.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention clearer, the present invention will be described in further detail with reference to the accompanying drawings.
Example 1:
as shown in fig. 1, the utility model provides a mechanical properties adjustable truss structure, included a plurality of "Z" font structure's bracing piece, the two-dimensional frame element of central symmetry that the mirror image of bracing piece connected the combination and formed, the upper and lower bracing piece of "Z" font structure's bracing piece is parallel structure, has the same length L and design angle alpha.
In other embodiments, three segments of support rods with different lengths may be selected to form a zigzag structure, which is not limited herein.
The design angle is preferably an acute angle, and the negative poisson ratio phenomenon of the obtained truss structure is obvious.
In this embodiment, 8 support rods having a zigzag structure are connected to form a two-dimensional frame unit.
In the present embodiment, the six two-dimensional frame units constitute a three-dimensional structure unit, and the three-dimensional structure unit has a hexahedral structure.
Adjacent two-dimensional frame elements of the six two-dimensional frame elements have shared edges, i.e. a surface-to-surface connection is formed using a common support bar.
The same two-dimensional frame unit is used between each three-dimensional structure unit of the plurality of three-dimensional structure units.
The length-to-diameter ratio of the supporting rod is defined as d/L, and the truss structures with different mechanical properties are obtained by controlling parameters and an included angle alpha.
As shown in fig. 1, several groups of samples with different design angles are designed, wherein α is 50 °, 60 °, and70 °, and L is 2 mm.
As shown in fig. 2, four sets of products were manufactured with the design parameters α being 50 °, 60 °, and70 °, L being 2mm, 0.27, and 0.47, and the numbers and parameters are as follows: (sample No., α,) (#1, 50 °, 0.27), (#2, 60 °, 0.27), (#3, 70 °, 0.27), (#4, 60 °, 0.47). The adjustment of the truss structure and the influence on the overall mechanical properties of the parameter alpha can be obtained by comparative studies on samples # 1, #2 and # 3. Comparative studies on samples # 2 and #4 can show the effect of the length to diameter ratio of the strut on the variation and overall mechanical performance of the truss structure.
The truss structure of this embodiment is fabricated by the following steps.
As shown in fig. 1, a "Z" shaped structure is constructed by using three support rods with the same length L, the three support rods form a design angle α ═ ABC ═ BCD ═ α, the length | AB | ═ BC | ═ CD | ═ L of the support rod of the "Z" shaped structure, the diameter of the rod is d, and the length-to-diameter ratio of the support rod is defined as d/L.
8 symmetrical Z-shaped structures are connected in a mirror image mode to form a centrosymmetric two-dimensional frame unit in a mirror image mode, one Z-shaped structure is subjected to 45-degree mirror image to obtain two Z-shaped structure connecting structures, then the four Z-shaped structure connecting structures are obtained through 180-degree mirror image, and then the eight Z-shaped structure connecting structures are obtained through 180-degree mirror image, so that a centrosymmetric and axisymmetric structure is obtained.
The three-dimensional structural unit of the hexahedral structure is constructed in such a manner that 6 two-dimensional frame units use the same shared edge.
And forming a truss unit of a three-dimensional space structure by using a plurality of three-dimensional structure units with the same connecting surface.
In the utility model, the Porosity of the sample piece is defined as Porosity ═ 100% -Vl/VsIn which V islAnd VsRepresenting the volume of the truss structure and the volume of the corresponding total cube, respectively, wherein: vl＝Ml/ρl，MlAnd ρlIndicating the mass of the sample and the density of the material used, respectively.
A5 KN universal force tester was used. All samples were compressed at a constant rate of 5mm/min to failure. Three experiments were repeated, each with three samples and tested. Using the ISO-13314 standard, stiffness is determined by the maximum slope of the stress versus strain curve for the linear elastic region, yield strength is determined using the 0.2% deformation displacement method, and the first maximum strength is defined as the first local maximum strength of the stress-strain curve (see fig. 3B).
The measured data are shown in table 1. The measured results are expressed in the form a + -b, where a represents the mean of three measurements,
Mmaxand MminThe maximum and minimum of the measured values, respectively.
Table 1:
in fig. 3, a is a deformation process of the truss structure sample piece pressure experiment. As can be seen from the figure, the sample cross section first increases and then decreases with increasing strain (see arrows at 0.32 and 0.5 strain), indicating that the truss structure has a negative poisson's ratio behavior.
B is a typical stress-strain relationship graph of products # 1- # 4. It can be seen from the figure that for the fixation, the design angle α plays an important role in the mechanical properties of the truss structure. The mechanical response of the samples # 1- #3 can be visually seen from their stress-strain curves, with the lower the α, the more rigid the truss structure and the lower the porosity.
C is a comparison of samples # 2 and #4, with the greater the fixed α, the greater the stiffness and the lower the porosity.
It can also be seen from the data in table 1 that, when unchanged, the design angle α increases, the size and porosity of the truss structural sample increases, the stiffness, yield strength and maximum strength decrease, and the mechanical properties deteriorate. When the design angle α is constant, the increased value may increase the stiffness, yield strength and first maximum strength, decreasing porosity.
Experiments show that the mechanical property of the truss structure can be adjusted by adjusting the sum of the designed geometric parameters alpha, so that the mechanical property of the structure is optimized. This helps us further achieve the target mechanical properties for a given application.
Furthermore, the truss structure described in this patent is hollow in three-dimensional cells, so a high porosity can be achieved.
In the experimental process, when the structure is damaged, the truss structure is often broken from the intersection point of the rod pieces, and the area is a stress concentration area.
Example 2:
in this embodiment, three two-dimensional frame units identical to those in embodiment 1 are used to combine a three-dimensional structural unit of another structural form.
The three two-dimensional frame units are connected with each other concentrically and orthogonally, namely, six end faces of the upper, lower, left, right, front and back of the formed three-dimensional structure unit are in a structure shaped like a Chinese character 'ji'.
The truss structure unit and its neighboring units of this embodiment share a "+" shaped structure.
The utility model has the advantages of as follows:
1. the utility model discloses the three-dimensional constitutional unit who forms is isotropic structure, its design parameter: the design angle alpha and the length-to-diameter ratio of the supporting rod are parametric design parameters. The model of different geometric relationships can be obtained quickly through parameter change without re-modeling, and isotropy is kept all the time.
2. The utility model discloses a structure can be through the value of the length of adjustment design angle alpha, bracing piece and diameter ratio, adjusts and controls the holistic mechanical properties of every three-dimensional structure unit, for example rigidity, yield strength, maximum strength etc. makes the whole mechanical properties of structure have designability.
3. The truss structure obtained by the utility model has the characteristic of auxetic (negative Poisson ratio).
4. The utility model discloses the truss structure who obtains has very high porosity (> 90%).
5. The utility model discloses an application area is wide, can be used to make light, negative poisson's ratio and have the novel material of anticipated mechanical properties.
The above description is only a preferred embodiment of the present invention, and certainly, the scope of the present invention should not be limited thereto, and therefore, the appended claims are intended to cover all such modifications as fall within the true scope of the invention.
Claims (7)
1. The truss structure with adjustable mechanical properties is characterized by comprising a centrosymmetric two-dimensional frame unit formed by connecting and combining a plurality of support rods of Z-shaped structures in a mirror image mode, wherein the support rods of the Z-shaped structures have the same design angle.
2. The mechanically tunable truss structure of claim 1 wherein said "zigzag" structure is formed by three equal lengths of said support rods.
3. The truss structure with adjustable mechanical properties according to claim 1 or 2, comprising three-dimensional structural units, wherein the three-dimensional structural units are hexahedral structures, and the hexahedral structures are formed by the two-dimensional frame units.
4. The mechanically tunable truss structure of claim 3 wherein adjacent ones of said two-dimensional framing units in said hexahedral structure have shared edges.
5. The mechanically tunable truss structure of claim 4 including a plurality of said three-dimensional structural units, adjacent ones of said three-dimensional structural units using the same two-dimensional framing unit therebetween.
6. The truss structure with adjustable mechanical properties of claim 1 or 2, comprising a three-dimensional structural unit, wherein the three-dimensional structural unit is composed of three two-dimensional frame units, and a concentric and orthogonal connection relationship is formed between every two three-dimensional frame units.
7. The mechanically tunable truss structure of claim 6 including a plurality of said three-dimensional structural units, adjacent ones of said three-dimensional structural units having the same orthogonal support struts of two of said two-dimensional framing units therebetween.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921550618.XU CN211315750U (en) | 2019-09-18 | 2019-09-18 | Truss structure with adjustable mechanical property |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921550618.XU CN211315750U (en) | 2019-09-18 | 2019-09-18 | Truss structure with adjustable mechanical property |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN211315750U true CN211315750U (en) | 2020-08-21 |
Family
ID=72053645
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201921550618.XU Active CN211315750U (en) | 2019-09-18 | 2019-09-18 | Truss structure with adjustable mechanical property |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN211315750U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110553135A (en) * | 2019-09-18 | 2019-12-10 | 汕头大学 | Truss structure with adjustable mechanical property and manufacturing method thereof |
| ES2907514A1 (en) * | 2021-03-15 | 2022-04-25 | Univ Madrid Politecnica | Meta-metamaterial and metamaterial unit formed from that cell unit (Machine-translation by Google Translate, not legally binding) |
-
2019
- 2019-09-18 CN CN201921550618.XU patent/CN211315750U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110553135A (en) * | 2019-09-18 | 2019-12-10 | 汕头大学 | Truss structure with adjustable mechanical property and manufacturing method thereof |
| ES2907514A1 (en) * | 2021-03-15 | 2022-04-25 | Univ Madrid Politecnica | Meta-metamaterial and metamaterial unit formed from that cell unit (Machine-translation by Google Translate, not legally binding) |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN211315750U (en) | Truss structure with adjustable mechanical property | |
| Muth et al. | Architected cellular ceramics with tailored stiffness via direct foam writing | |
| CN110553135A (en) | Truss structure with adjustable mechanical property and manufacturing method thereof | |
| Chen et al. | A multiscale study on the structural and mechanical properties of the luffa sponge from Luffa cylindrica plant | |
| CN111950095B (en) | Three-dimensional multicellular structure with adjustable poisson ratio and thermal expansion coefficient | |
| KR101682992B1 (en) | Auxetic structure based on wire-woven metal and fabrication method and appratus of the same | |
| CN109033486B (en) | Two-dimensional periodic negative Poisson ratio controllable auxetic material | |
| Li et al. | Auxetic mechanical metamaterials: from soft to stiff | |
| CN110689619A (en) | Three-dimensional structure unit, novel truss structure formed by three-dimensional structure unit and design method | |
| CN114013027B (en) | Construction method of strong-stability negative poisson ratio structure | |
| Amirkhani et al. | Manipulating failure mechanism of rapid prototyped scaffolds by changing nodal connectivity and geometry of the pores | |
| Wejrzanowski et al. | Appropriate models for simulating open-porous materials | |
| CN110457841A (en) | A method of characterization 3D printing diamond lattice structure mechanical property | |
| CN109938883B (en) | Dodecahedron rod structure unit, bone implant and mass transfer performance evaluation method thereof | |
| EP3323436A1 (en) | Porous material | |
| Zhang et al. | Experimental and simulated compressive properties of work-hardened X-type lattice truss structures | |
| CN210742944U (en) | Three-dimensional zero Poisson ratio microscopic structure based on star structure and macroscopic structure thereof | |
| Malek et al. | Structural implications of using cairo tiling and hexagons in gridshells | |
| CN214278944U (en) | Variable-rigidity negative Poisson ratio cell element | |
| CN214208590U (en) | Bearing structure | |
| Altintas | Vibration properties of TPMS based structures | |
| Boltenhagen et al. | Giant deformations and topological hysteresis of an ordered foam | |
| CN209775550U (en) | Three-dimensional auxetic structure with isotropy | |
| Uhlířová et al. | Application of stereological relations for the characterization of porous materials via microscopic image analysis | |
| WO2023069056A2 (en) | Truss-lattice materials consisting of mixed polygons |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |