Development of uni-stretch woven fabrics with zero and negative Poisson’s ratio

2017 ◽  
Vol 88 (18) ◽  
pp. 2076-2092 ◽  
Author(s):  
Adeel Zulifqar ◽  
Tao Hua ◽  
Hong Hu
Keyword(s):  
Poisson’S Ratio ◽  
Tensile Tests ◽  
Research Area ◽  
Woven Fabrics ◽  
Poisson's Ratio ◽  
Negative Poisson’S Ratio ◽  
Wide Range ◽  
Differential Shrinkage ◽  
Weaving Technology ◽  
Negative Poisson's Ratio

Fabrics with zero or negative Poisson’s ratio are referred as auxetic fabrics, which have the unusual property of lateral expansion or zero expansion upon stretch. The use of conventional materials and machinery to produce auxetic fabrics has gained the interest of researchers in recent years. However, this approach is limited to knitted fabrics only. The development of auxetic fabric using conventional yarns and weaving technology is a research area that is still unaddressed. This paper reports a study on the development of a novel class of stretchable auxetic woven fabrics by using conventional yarns and weaving machinery. The phenomenon of differential shrinkage was successfully employed to realize auxetic geometries capable of inducing auxetic behavior in woven fabrics, and a series of auxetic woven fabrics were fabricated with elastic and non-elastic yarns and a dobby machine. The uni-axial tensile tests showed that auxetic woven fabrics developed exhibited zero or negative Poisson’s ratio over a wide range of longitudinal strain.

Deformation behavior of auxetic woven fabric made of foldable geometry in different tensile directions

2020 ◽  
Vol 91 (1-2) ◽  
pp. 87-99
Author(s):  
Hasan Kamrul ◽  
Weiguo Dong ◽  
Adeel Zulifqar ◽  
Shuaiquan Zhao ◽  
Minglonghai Zhang ◽  
...  
Keyword(s):  
Poisson’S Ratio ◽  
Tensile Deformation ◽  
Tensile Loading ◽  
Woven Fabrics ◽  
Woven Fabric ◽  
Poisson's Ratio ◽  
Negative Poisson’S Ratio ◽  
Ratio Effect ◽  
Negative Poisson's Ratio ◽  
Principal Directions

Auxetic woven fabrics made with special geometrical structures have gained the interest of textile scientists in recent years. This paper reports a study on auxetic woven fabric based on a double-directional parallel in-phase zig-zag foldable geometrical structure. Such a fabric has been already produced and investigated for its negative Poisson's ratio effect in two principal directions (weft and warp directions). However, its negative Poisson's ratio effect in biased tensile directions as well as under repeated tensile loading conditions has not been studied yet. Therefore, in this paper, these two limitations are addressed. The auxetic woven fabric was firstly fabricated, and then subjected not only to tensile tests in different tensile directions, including two principle directions and three biased directions, but also to repeated tensile loading. It was found that both the negative Poisson's ratio effect and the resistance to tensile deformation are dependent upon the tensile direction, and the highest negative Poisson's ratio effect and higher resistance to tensile deformation are obtained in two principal directions.

scholarly journals Analytical relationships for re-entrant honeycombs

2020 ◽  
Author(s):  
Reza Hedayati ◽  
Naeim Ghavidelnia
Keyword(s):  
Yield Stress ◽  
Analytical Solutions ◽  
Poisson’S Ratio ◽  
Poisson's Ratio ◽  
Negative Poisson’S Ratio ◽  
Fe Method ◽  
Wide Range ◽  
Unit Cells ◽  
Negative Poisson's Ratio ◽  
Internal Angle

Mechanical metamaterials have emerged in the last few years as a new type of artificial material which show properties not usually found in nature. Such unprecedented properties include negative stiffness, negative Poisson’s ratio, negative compressibility and fluid-like behaviors. Unlike normal materials, materials with negative Poisson’s ratio (NPR), also known as auxetics, shrink laterally when a compressive load is applied to them. The 2D re-entrant honeycombs are the most prevalent auxetic structures and many studies have been dedicated to study their stiffness, large deformation behavior, and shear properties. Analytical solutions provide inexpensive and quick means to predict the behavior of 2D re-entrant structures. There have been several studies in the literature dedicated to deriving analytical relationships for hexagonal honeycomb structures where the internal angle θ is positive (i.e. when the structure has positive Poisson’s ratio). It is usually assumed that such solutions also work for corresponding re-entrant unit cells. The goal of this study was to find out whether or not the analytical relationships obtained in the literature for θ>0 are also applicable to 2D-reentrant structures (i.e. when θ<0). Therefore, this study focused on unit cells with a wide range of internal angles from very negative to very positive values. For this aim, new analytical relationships were obtained for hexagonal honeycombs with possible negativity in the internal angle θ in mind. Numerical analyses based on finite element (FE) method were also implemented to validate and evaluate the analytical solutions. The results showed that, as compared to analytical formulas presented in the literature, the analytical solutions derived in this work give the most accurate results for elastic modulus, Poisson’s ratio, and yield stress. Moreover, some of the formulas for yield stress available in the literature fail to be valid for negative ranges of internal angle (i.e. for auxetics). However, the yield stress results of the current study demonstrated good overlapping with numerical results in both the negative and positive domains of θ.

scholarly journals Tunable Negative Poisson’s Ratio in Van der Waals Superlattice

Research ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Xiaowen Li ◽  
Xiaobin Qiang ◽  
Zhenhao Gong ◽  
Yubo Zhang ◽  
Penglai Gong ◽  
...  
Keyword(s):  
Poisson’S Ratio ◽  
Electronic Band Structure ◽  
Hexagonal Boron Nitride ◽  
Van Der Waals ◽  
Poisson's Ratio ◽  
Negative Poisson’S Ratio ◽  
Electronic Band ◽  
Mechanical Metamaterials ◽  
Wide Range ◽  
Negative Poisson's Ratio

Negative Poisson’s ratio (NPR) materials are functional and mechanical metamaterials that shrink (expand) longitudinally after being compressed (stretched) laterally. By using first-principles calculations, we found that Poisson’s ratio can be tuned from near zero to negative by different stacking modes in van der Waals (vdW) graphene/hexagonal boron nitride (G/h-BN) superlattice. We attribute the NPR effect to the interaction of pz orbitals between the interfacial layers. Furthermore, a parameter calculated by analyzing the electronic band structure, namely, distance-dependent hopping integral, is used to describe the intensity of this interaction. We believe that this mechanism is not only applicable to G/h-BN superlattice but can also explain and predict the NPR effect in other vdW layered superlattices. Therefore, the NPR phenomenon, which was relatively rare in 3D and 2D materials, can be realized in the vdW superlattices by different stacking orders. The combinations of tunable NPRs with the excellent electrical/optical properties of 2D vdW superlattices will pave a novel avenue to a wide range of multifunctional applications.

Design, preparation, and characterization of auxetic weft backed weave fabrics based on Miura origami structure

2021 ◽  
pp. 004051752110505
Author(s):  
Qiaoli Xu ◽  
Longxin Gu ◽  
Gui Liu ◽  
Zhuoran Liu ◽  
Dongdong Lu ◽  
...  
Keyword(s):  
Poisson’S Ratio ◽  
Physical Map ◽  
Structure Type ◽  
Poisson's Ratio ◽  
Negative Poisson’S Ratio ◽  
Auxetic Materials ◽  
Out Of Plane ◽  
Weaving Technology ◽  
Negative Poisson's Ratio

The metamaterials with negative Poisson’s ratio are called auxetic materials, which as a branch of metamaterials has drawn a lot of attention in many areas. Existing auxetic knitting textiles combine flexibility and auxeticity, however the loose structure has been a main disadvantage for its application. In this study, we fabricated Miura origami structure fabrics by weaving technology in order to acquire more stable auxetic textiles. The results show that using the combination of fabric structure type and elastic yarns, an origami structure can be realized in a jacquard loom. In the Miura origami structure, the crease pattern can be separated into three parts, unfolding areas, convex areas, and concave areas. One warp system and two weft systems are compounded together, in which a weft backed weave is used to get elastic floats in the convex and concave areas, and to make the fabrics bend to the concave side. The physical map showed that the fabrics had a clear Miura origami structure and the unfolding areas were flat and even. On the basis of the designed geometric pattern, weft backed weaves can be used to construct different folded areas, spandex wrapped PET (Polyester) and inelastic PET are selected as two weft systems for weaving. Meanwhile, the Miura origami fabrics exhibit distinct in-plane negative Poisson’s ratio and out-of-plane positive Poisson’s ratio. Apart from the Miura origami structure, other origami and paper-cut structures can be realized using this method, and these special auxetic textiles have potential in protective cloths, ornamented textiles, wearable devices, and flexible sensors.

INFLUENCE OF NEGATIVE POISSON’S RATIO ON FRACTURE MORPHOLOGIES IN CFRP LAMINATES

2021 ◽  
Author(s):  
DAIKI IWASAKI ◽  
SHUICHIRO NISHIO ◽  
HIROSHI SAITO ◽  
MANATO- KANESAKI, ◽  
ISAO KIMPARA
Keyword(s):  
Poisson’S Ratio ◽  
Fracture Morphology ◽  
Tensile Tests ◽  
Poisson's Ratio ◽  
Negative Poisson’S Ratio ◽  
Cfrp Laminates ◽  
Loading Direction ◽  
Negative Poisson's Ratio ◽  
The Relationship ◽  
Fracture Morphologies

The Poisson's ratio and Young's modulus of CFRP laminates can be varied by changing their stacking sequences. CFRP with the specific stacking sequence can theoretically perform the “negative” Poisson’s ratio, which causes extension in the direction perpendicular to the loading direction, for example. However, the relationship between Poisson's ratio and fracture morphology has not yet been elucidated. In this study, tensile tests were performed for CFRP laminates with negative, zero and positive Poisson’s ratios, and failure morphologies were experimentally investigated.

Deformation behavior of auxetic woven fabric based on re-entrant hexagonal geometry in different tensile directions

2019 ◽  
Vol 90 (3-4) ◽  
pp. 410-421 ◽  
Author(s):  
Hasan Kamrul ◽  
Adeel Zulifqar ◽  
Hong Hu
Keyword(s):  
Deformation Behavior ◽  
Geometrical Structure ◽  
Tensile Loading ◽  
Tensile Tests ◽  
Woven Fabrics ◽  
Woven Fabric ◽  
Poisson's Ratio ◽  
Negative Poisson’S Ratio ◽  
Tensile Direction ◽  
Negative Poisson's Ratio

Auxetic woven fabrics made of non-auxetic yarns have gained the interest of textile scientists in recent times. Such fabrics have already been produced and investigated for their negative Poisson's ratio (NPR) effect in two principle directions. However, the NPR effect of these fabrics in different biased tensile directions has not been studied. In particular, the influence of repeated tensile loading on the NPR effect retention ability of fabric has not been explored yet. Therefore, this paper aims to report the NPR effect of auxetic woven fabric in different tensile directions and the influence of repeating tensile cycle tests on its NPR effect retention ability. The auxetic woven fabric is firstly fabricated based on a re-entrant hexagonal geometrical structure by using elastic and non-elastic yarns, and then subjected to single and repeating tensile tests in five different tensile directions, which include two principle directions and three biased directions. It is found that the NPR effect is largely dependent upon the tensile direction and the number of repeating tensile cycles.

Free vibration and sound insulation of functionally graded honeycomb sandwich plates

2021 ◽  
pp. 109963622110204
Author(s):  
Fenglian Li ◽  
Wenhao Yuan ◽  
Chuanzeng Zhang
Keyword(s):  
Free Vibration ◽  
Poisson’S Ratio ◽  
Functionally Graded ◽  
Poisson's Ratio ◽  
Dynamic Equations ◽  
Sound Insulation ◽  
Sandwich Plates ◽  
Negative Poisson’S Ratio ◽  
Honeycomb Sandwich ◽  
Negative Poisson's Ratio

Based on the hyperbolic tangent shear deformation theory, free vibration and sound insulation of two different types of functionally graded (FG) honeycomb sandwich plates with negative Poisson’s ratio are studied in this paper. Using Hamilton’s principle, the vibration and vibro-acoustic coupling dynamic equations for FG honeycomb sandwich plates with simply supported edges are established. By applying the Navier’s method and fluid–solid interface conditions, the derived governing dynamic equations are solved. The natural frequencies and the sound insulation of FG honeycomb sandwich plates obtained in this work are compared with the numerical results by the finite element simulation. It is proven that the theoretical models for the free vibration and the sound insulation are accurate and efficient. Moreover, FG sandwich plates with different honeycomb cores are investigated and compared. The corresponding results show that the FG honeycomb core with negative Poisson’s ratio can yield much lower frequencies. Then, the influences of various geometrical and material parameters on the vibration and sound insulation performance are systematically analyzed.

Sign in / Sign up

Export Citation Format

Share Document