Auxeticity of Calcite and Aragonite polymorphs of CaCO<sup>3</sup> and crystals of similar structure

Aouni, Nizar; Wheeler, Lewis

doi:10.1002/pssb.200880264

Cited by 10 publications

(11 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Among structural networks are molecular networks 3 , hierarchical structures 4 , composites 5 and hinged structures 22,23 . Some materials exhibit auxetic properties as they are stretched or compressed in a proper direction [6][7][8][9][24][25][26][27][28][29][30] . For example, Baughman et al 7 reported that 69% of all cubic materials exhibit a negative Poisson's ratio along the [1 10]-direction when they are subjected to stretching along the [110]-direction.…”

mentioning

confidence: 99%

Negative Poisson’s ratios in metal nanoplates

et al. 2014

View full text Add to dashboard Cite

The Poisson's ratio is a fundamental measure of the elastic-deformation behaviour of materials. Although negative Poisson's ratios are theoretically possible, they were believed to be rare in nature. In particular, while some studies have focused on finding or producing materials with a negative Poisson's ratio in bulk form, there has been no such study for nanoscale materials. Here we provide numerical and theoretical evidence that negative Poisson's ratios are found in several nanoscale metal plates under finite strains. Furthermore, under the same conditions of crystal orientation and loading direction, materials with a positive Poisson's ratio in bulk form can display a negative Poisson's ratio when the material's thickness approaches the nanometer scale. We show that this behaviour originates from a unique surface effect that induces a finite compressive stress inside the nanoplates, and from a phase transformation that causes the Poisson's ratio to depend strongly on the amount of stretch.

show abstract

mentioning

confidence: 99%

Negative Poisson’s ratios in metal nanoplates

et al. 2014

View full text Add to dashboard Cite

show abstract

“…Note that expressions (11)(12)(13)(14)(15)(16)) allow one to calculate E, G and ν for a given pair of direction vectors (m, n) and for chosen values of s 1 , s 2 and s 3 . In the case of polycrystalline materials numerical calculation provides one with analogous results.…”

Section: Mechanical Characteristics Of Quadratic and Cubic Materialsmentioning

confidence: 99%

Quadratic and cubic monocrystalline and polycrystalline materials: their stability and mechanical properties

Jasiukiewicz¹,

Paszkiewicz²,

Wołski³

2010

J. Phys.: Conf. Ser.

View full text Add to dashboard Cite

We consider 2-and 3-dimensional cubic monocrystalline and polycrystalline materials. Expressions for Young's and shear moduli and Poisson's ratio are expressed in terms of eigenvalues of the stiffness tensor. Such a form is well suited for studying properties of these mechanical characteristics on sides of the stability triangles. For crystalline highsymmetry directions lines of vanishing Poisson's ratio are found. These lines demarcate regions of the stability triangle into areas of various auxeticity properties. The simplest model of polycrystalline 2D and 3D cubic materials is considered. In polycrystalline phases the region of complete auxetics is larger than for monocrystalline materials.

show abstract

“…Fracture toughness and resistance to indentation increase as Poisson's ratio approaches the lower (isotropic) limit of −1.0 (Yeganeh-Haeri et al, 1992). In rock forming minerals, negative Poisson's ratios have already been documented for α-cristobalite (Yeganeh-Haeri et al, 1992), for quartz at the α-β phase transition (Mainprice & Casey, 1990), for talc (Mainprice et al, 2008), and for calcite and aragonite (Aouni & Wheeler, 2008). A key question therefore is to determine if there are other rock forming minerals with the same properties, and for which specific crystallographic directions.…”

Section: Introductionmentioning

confidence: 99%

The variation and visualisation of elastic anisotropy in rock-forming minerals

Healy¹,

Timms²,

Pearce³

2019

Preprint

View full text Add to dashboard Cite

All minerals behave elastically, a rheological property that controls their ability to support stress, strain and pressure, the nature of acoustic wave propagation and influences subsequent plastic (i.e. permanent, non-reversible) deformation. All minerals are intrinsically anisotropic in their elastic properties – that is, they have directional variations that are related to the configuration of the crystal lattice. This means that the commonly used mechanical elastic properties that relate elastic stress to elastic strain, including Young’s modulus (E), Poisson’s ratio (ν), shear modulus (G) and linear compressibility (β), are dependent on crystallographic direction. In this paper, we explore the ranges of anisotropy of E, ν, G and β in 86 rock-forming minerals, using previously published data, and show that the range is much wider than commonly assumed. We also explore how these variations (the directionality and the magnitude) are important for fundamental processes in the solid earth, including deformation (mechanical) twinning, coherent phase transformations and brittle failure. We present a new open source software package (AnisoVis, written in MATLAB), which we use to calculate and visualise directional variations in elastic properties of rock-forming minerals. Following previous work in the fields of chemistry and materials, we demonstrate that by visualising the variations in elasticity, we discover previously unreported properties of rock forming minerals. For example, we show previously unreported directions of negative Poisson’s ratio and negative linear compressibility and we show that the existence of these features is more widespread (i.e. present in many more minerals) than previously thought. We illustrate the consequences of intrinsic elastic anisotropy for the elastic normal and shear strains within α-quartz single crystal under different applied stress fields; the role of elastic anisotropy on Dauphiné twinning and the α-β phase transformations in quartz; and stress distributions around voids of different shapes in talc, lizardite, albite, and sanidine. In addition to our specific examples, elastic anisotropy in rock-forming minerals to the degree that we describe has significant consequences for seismic (acoustic) anisotropy, the focal mechanisms of earthquakes in anisotropic source regions (e.g. subducting slabs), for a range of brittle and ductile deformation mechanisms in minerals, and geobarometry using mineral inclusions.

show abstract

Auxeticity of Calcite and Aragonite polymorphs of CaCO³ and crystals of similar structure

Cited by 10 publications

References 24 publications

Negative Poisson’s ratios in metal nanoplates

Negative Poisson’s ratios in metal nanoplates

Quadratic and cubic monocrystalline and polycrystalline materials: their stability and mechanical properties

The variation and visualisation of elastic anisotropy in rock-forming minerals

Contact Info

Product

Resources

About

Auxeticity of Calcite and Aragonite polymorphs of CaCO3 and crystals of similar structure

Cited by 10 publications

References 24 publications

Negative Poisson’s ratios in metal nanoplates

Negative Poisson’s ratios in metal nanoplates

Quadratic and cubic monocrystalline and polycrystalline materials: their stability and mechanical properties

The variation and visualisation of elastic anisotropy in rock-forming minerals

Contact Info

Product

Resources

About

Auxeticity of Calcite and Aragonite polymorphs of CaCO³ and crystals of similar structure