Stretch-induced wrinkles usually occur in a thin, clamped-clamped, hyperelastic film and eventually disappear upon excess stretching, with wrinkling direction being perpendicular to the stretching direction within isotropic elasticity framework. Here, we consider in-plane anisotropy induced by infilling fibers in thin films, which significantly affects the orientation and amplitude of wrinkles.
Dear iMechanicians, I would like to share our recent work on a drop confined by two adhesive graphene sheets (as illustrated below).
Tribological behavior of graphene layers has been a focus of intensive research interest since its crystal lattice structure can be exploited to achieve incommensurate contact, leading to nearly zero friction, namely structural superlubricity. However, wrinkling undulations are omnipresent on graphene and difficult to be completely eliminated, which inevitably resists superlubricity in reality. Here, we explore how the presence of surface wrinkles affects nanotribological behavior of graphene sliding systems.
Tensional wrinkles are widely observed in elastic thin films, with mono-orientation of wrinkles being usually perpendicular to the stretching direction. Here, by changing material orthotropic direction, we present orientable wrinkles in uniaxially stretched orthotropic membranes. To quantitatively explore orthotropy-related wrinkles and their morphological evolution, we develop a mathematical model by introducing orthotropic, elastic constitution into the extended F\"oppl-von K\'arm\'an nonlinear plate theory that can describe large in-plane anisotropic deformations.
Smart soft materials, because of their mechanical flexibility and quick response to multi-physics stimuli, have drawn considerable attention over the past few years. Here, we present controllable wrinkling patterns of a liquid crystal polymer film attached on a soft substrate, controlled by laser illumination that holds unique optical characteristics of high coherence and irradiance.
Title: Non-uniform curvature and anisotropic deformation control wrinkling patterns on tori
Wrinkles in layered neo-Hookean structures were recently formulated as a Hamiltonian system by taking the thickness direction as a pseudo-time variable. This enabled an efficient and accurate numerical method to solve the eigenvalue problem for onset wrinkles. Here, we show that wrinkles in graded elastic layers can also be described as a time-varying Hamiltonian system. The connection between wrinkles and the Hamiltonian system is established through an energy method.
Soft dielectric elastomer is able to generate an
electromechanical response in terms of reversible shape
changing, which is a muscle-like behavior. The deformation
and electromechanical stability of dielectric elastomers,
classified by their deformation modes, uniaxial extension,
equal biaxial expansion and pure shear, are investigated.
Pull-in instability occurs in equal biaxial and uniaxial modes
at a small stretch ratio, while the pure shear mode features
wrinkling instability after a large stable deformation. The
