Results 141 to 150 of about 22,427 (184)

Negative Poisson's ratio in rippled graphene

Nanoscale, 2017
In this work, we perform molecular dynamics (MD) simulations to study the effect of rippling on the Poisson's ratio of graphene. Due to the atomic scale thickness of graphene, out-of-plane ripples are generated in free standing graphene with topological defects (e.g. heptagons and pentagons) to release the in-plane deformation energy.
Huasong Qin, Yu Sun, Jefferson Zhe Liu, Mengjie Li, Yilun Liu   +4 more
openaire   +2 more sources

Negative Poisson's ratio in graphene oxide

Nanoscale, 2017
We perform molecular dynamics simulations to investigate the Poisson's ratio of graphene oxide. We find that the Poisson's ratio can be effectively tuned by increasing the degree of oxidation of graphene oxide. More specifically, the Poisson's ratio decreases linearly from positive to negative with increasing oxidation, turning negative at room ...
Jing Wan, Jin-Wu Jiang, Harold S. Park
openaire   +2 more sources

Negative Poisson’s Ratio Polyester Fibers

Textile Research Journal, 2006
Auxetic materials are referred to as those having negative Poisson’s ratio (ν). Initial work at Bolton successfully fabricated auxetic polypropylene fiber using a novel thermal melt-spinning technique. This paper reports in detail both the methods and principles involved in screening polyester powder and also the manufacturing method for successful ...
Naveen Ravirala, Kim L. Alderson, Philip J. Davies, Virginia R. Simkins, Andrew Alderson   +4 more
openaire   +1 more source

Negative Poisson's ratio polyethylene foams

Journal of Materials Science, 2001
Various polyethylene foams were subjected to thermo-mechanical processing with the aim of transforming them into re-entrant materials exhibiting negative Poisson's ratio. Following transformation, large cell foams (cell sizes of 1 and 2 mm) exhibited re-entrant cell structure and negative Poisson's ratio over a range of processing times and ...
B. Brandel, R. S. Lakes
openaire   +1 more source

A negative Poisson’s ratio carbon fibre composite using a negative Poisson’s ratio yarn reinforcement

Composites Science and Technology, 2012
Abstract The manufacture of negative Poisson’s ratio (auxetic) composites, containing inherently auxetic phases is rare and has been confined to relatively low modulus composite systems with stiffnesses several orders of magnitude below those of structural composites. This paper presents the use of an auxetic double helix yarn that is used to produce
W. Miller, Z. Ren, C.W. Smith, K.E. Evans   +3 more
openaire   +1 more source

3D Soft Metamaterials with Negative Poisson's Ratio

Advanced Materials, 2013
Buckling is exploited to design a new class of three-dimensional metamaterials with negative Poisson's ratio. A library of auxetic building blocks is identified and procedures are defined to guide their selection and assembly. The auxetic properties of these materials are demonstrated both through experiments and finite element simulations and exhibit ...
Sahab, Babaee, Jongmin, Shim, James C, Weaver, Elizabeth R, Chen, Nikita, Patel, Katia, Bertoldi   +5 more
openaire   +2 more sources

Oxidation-induced negative Poisson’s ratio of phosphorene

Journal of Physics: Condensed Matter, 2018
Mechanical properties of phosphorene oxides are investigated by using density functional theory calculations. Intriguingly, as the oxygen coverage approaches 50%, negative Poisson's ratios are found in the in-plane principal directions, originating from the asymmetric atomic structure upon oxygen adsorption.
Feng Hao, Xiangbiao Liao, Mingjia Li, Hang Xiao, Xi Chen   +4 more
openaire   +2 more sources

Nonlinear Analysis of the Poisson's Ratio of Negative Poisson's Ratio Foams

Journal of Composite Materials, 1995
This article contains an analytic study of Poisson's ratio of re-entrant foam materials with negative Poisson's ratio. These materials get fatter when stretched and thinner when compressed. The Poisson effect is so fundamentally important to the properties of a material that a large change in the value of the ratio will have significant effects on the
J. B. Choi, R. S. Lakes
openaire   +1 more source

Tailoring Graphene to Achieve Negative Poisson's Ratio Properties

Advanced Materials, 2014
Graphene can be made auxetic through the introduction of vacancy defects. This results in the thinnest negative Poisson's ratio material at ambient conditions known so far, an effect achieved via a nanoscale de-wrinkling mechanism that mimics the behavior at the macroscale exhibited by a crumpled sheet of paper when stretched.
Grima J. N., Winczewski S., Mizzi L., Grech M. C., Cauchi R., Gatt R., Attard D., Wojciechowski K. W., Rybicki J.   +8 more
openaire   +2 more sources

Negative Poisson’s Ratio Weft-knitted Fabrics

Textile Research Journal, 2009
This paper presents a study of using weft-knitting technology to fabricate negative Poisson’s ratio (NPR) knitted fabrics, which exhibit the unusual property of becoming wider when stretched. Based on a geometrical analysis of a three-dimensional NPR structure constructed with parallelogram planes of the same shape and size, a new kind of NPR weft ...
null Yanping Liu, null Hong Hu, Jimmy K. C. Lam, null Su Liu   +3 more
openaire   +1 more source