Contact Analyses for Anisotropic Half Space: Effect of the Anisotropy on the Pressure Distribution and Contact Area

Bagault, Caroline; Nélias, Daniel; Baietto, Marie-Christine

doi:10.1115/1.4006747

Cited by 24 publications

(14 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A better insight into the contact-pressure distribution as a function of the material elastic constants can be obtained using simulations with SAMs, which have proved their efficiency in describing the contact mechanics of anisotropic materials [44][45][46] . Here, we use SAM to simulate the force versus indentation curves in graphite.…”

Section: Semi-analytical Methodsmentioning

confidence: 99%

Elastic coupling between layers in two-dimensional materials

et al. 2015

Self Cite

View full text Add to dashboard Cite

Two-dimensional materials, such as graphene and MoS2, are films of a few atomic layers in thickness with strong in-plane bonds and weak interactions between the layers. The in-plane elasticity has been widely studied in bending experiments where a suspended film is deformed substantially; however, little is known about the films' elastic modulus perpendicular to the planes, as the measurement of the out-of-plane elasticity of supported 2D films requires indentation depths smaller than the films' interlayer distance. Here, we report on sub-ångström-resolution indentation measurements of the perpendicular-to-the-plane elasticity of 2D materials. Our indentation data, combined with semi-analytical models and density functional theory, are then used to study the perpendicular elasticity of few-layer-thick graphene and graphene oxide films. We find that the perpendicular Young's modulus of graphene oxide films reaches a maximum when one complete water layer is intercalated between the graphitic planes. This non-destructive methodology can map interlayer coupling and intercalation in 2D films.

show abstract

Section: Semi-analytical Methodsmentioning

confidence: 99%

Elastic coupling between layers in two-dimensional materials

et al. 2015

Self Cite

View full text Add to dashboard Cite

show abstract

“…, c N . The additional equation for a unique solution is provided by the equilibrium condition (53), which becomes …”

Section: Flat Stampmentioning

confidence: 99%

“…The two-dimensional frictionless sliding contact over orthotropic piezoelectric medium indented by a rigid sliding punch was investigated by Zhou and Lee [52]. Using semianalytical methods, Bagault et al [53,54] studied the effect of anisotropy orientation on the contact solution of an anisotropic half space indented by a rigid sphere. The boundary element method (BEM) was also used to solve the generalized plane contact problems of the anisotropic materials with possible friction contact zones [55,56] (see Blazquez et al.…”

mentioning

confidence: 99%

Mechanics of sliding frictional contact for a graded orthotropic half-plane

2015

View full text Add to dashboard Cite

The main interest in this study is the crack initiation in graded orthotropic materials under sliding contact conditions. We consider the two-dimensional sliding contact problem between a graded orthotropic half-plane and a rigid punch with an arbitrary profile. The orthotropic graded half-plane is modeled as a linearly elastic and locally inhomogeneous orthotropic material with an exponentially varying Young's modulus in the depth direction. The principal axes of orthotropy are assumed to be parallel and perpendicular to the contact surface. The problem is formulated under plane strain or generalized plane stress conditions. Using the standard Fourier transform, the problem is reduced to a singular integral equation, which is solved numerically using Jacobi polynomials. Extensive parametric study is done to determine the effect of the inhomogeneity parameter, β, the friction coefficient between the half-plane and the stamp, η, as well as the material orthotropic elastic parameters: the stiffness ratio, δ, the effective Poisson's ratio, ν, and the shear parameter, κ, on the contact stress distribution and stress intensity factors at the sharp edges of the stamps that may have a bearing on the fatigue and fracture of the graded orthotropic half-plane.

show abstract

“…Pitt and co-workers [12] subsequently modified Eqs. (1) and (2) to be applicable for elongated tablets by multiplying both equations by a factor of 2/3-this factor is exact only for the limiting case of large length to width ratios. Shang et al [16] adopted the form of Pitt's original equation and calibrated its empirical coefficients to an extensive experimental campaign of doubly convex microcrystalline cellulose tablets with various curvatures and of various relative densities.…”

Section: Introductionmentioning

confidence: 99%

General and mechanistic optimal relationships for tensile strength of doubly convex tablets under diametrical compression

Razavi

Gonzalez

Cuitiño

2015

International Journal of Pharmaceutics

View full text Add to dashboard Cite

We propose a general framework for determining optimal relationships for tensile strength of doubly convex tablets under diametrical compression. This approach is based on the observation that tensile strength is directly proportional to the breaking force and inversely proportional to a non-linear function of geometric parameters and materials properties. This generalization reduces to the analytical expression commonly used for flat faced tablets, i.e., Hertz solution, and to the empirical relationship currently used in the pharmaceutical industry for convex-faced tablets, i.e., Pitt's equation. Under proper parametrization, optimal tensile strength relationship can be determined from experimental results by minimizing a figure of merit of choice. This optimization is performed under the first-order approximation that a flat faced tablet and a doubly curved tablet have the same tensile strength if they have the same relative density and are made of the same powder, under equivalent manufacturing conditions. Furthermore, we provide a set of recommendations and best practices for assessing the performance of optimal tensile strength relationships in general. Based on these guidelines, we identify two new models, namely the general and mechanistic models, which are effective and predictive alternatives to the tensile strength relationship currently used in the pharmaceutical industry.

show abstract

Contact Analyses for Anisotropic Half Space: Effect of the Anisotropy on the Pressure Distribution and Contact Area

Cited by 24 publications

References 42 publications

Elastic coupling between layers in two-dimensional materials

Elastic coupling between layers in two-dimensional materials

Mechanics of sliding frictional contact for a graded orthotropic half-plane

General and mechanistic optimal relationships for tensile strength of doubly convex tablets under diametrical compression

Contact Info

Product

Resources

About