determination of the optimum loading path (internal pressure- axial feeding) to restrict the bursting, buckling and wrinkling through tube hydroforming process is necessary to produce an acceptable tube. in this paper, the wrinkling and fracture criteria are implemented to an finite element code devoted to the simulation of tube hydroforming processes. using the ansys parametric design language...

Purpose Tilt table testing mainly evaluates the systemic cardiovascular part of the autonomic nervous system, while it is assumed that the finger wrinkling test assesses the peripheral part of the autonomic nervous system. In this study we explored whether the finger wrinkling test could be a useful test for autonomic dysfunction and whether the clinical evaluation of wrinkling can be improved ...

Thermally induced film wrinkling is a fabrication and reliability challenge for thin-film stacks consisting of a compliant film capped by a stiffer film. The current understanding of film wrinkling is largely restricted to thin-film stacks on blanket substrates. An understanding of wrinkling in thin-film stacks on patterned substrates is of greater practical relevance to the microelectronic ind...

The branching of un,symmetric equilibrium states from axisymmetric equilibrium states for clamped circular plates subjected to a uniform edge thrust and a uniform lateral pressure is analyzed in this paper. The branching process is called wrinkling and the loads at which branching occurs are called wrinkling loads. The nonlinear von Karman plate theory is employed. The wrinkling loads are deter...

By combining surface wrinkling and nanopatterned polymer films, we create anisotropic, hierarchical surfaces whose larger length-scale (wrinkling wavelength) depends intimately on the geometry and orientation of the smaller length-scale (nanopattern). We systematically vary the pattern pitch, pattern height, and residual layer thickness to ascertain the dependence of the wrinkling wavelength on...

The wrinkling of a thin elastic bi-annular plate with piecewise-constant mechanical properties, subjected to radial stretching, is considered. The critical wrinkling stretching loading and the corresponding wrinkling patterns are extensively investigated, together with the roles played by both the geometrical and mechanical parameters. Keywords—bi-annular plate, wrinkling pattern, critical stre...

Human non-hairy (glabrous) skin of the fingers, palms and soles wrinkles after prolonged exposure to water. Wrinkling is a sympathetic nervous system-dependent process but little is known about the physiology and potential functions of water-induced skin wrinkling. Here we investigated the idea that wrinkling might improve handling of wet objects by measuring the performance of a large cohort o...

BACKGROUND/PURPOSE Does the morphology of wrinkles alter gradually with aging or suddenly at a certain age? On the basis of the theoretic wrinkle simulation of ideal skin, we have suggested that the wrinkle morphology suddenly changes from stratum corneum wrinkling to epidermis wrinkling; the former induces shallow fine furrows, and the latter induces deep prominent wrinkles. To examine the exi...

Compression of a stiff film on a soft substrate may lead to surface wrinkling when the compressive strain reaches a critical value. Further compression may cause a wrinkling-folding transition, and the sinusoidal wrinkling mode can then give way to a period-doubling bifurcation. The onset of the primary bifurcation has been well understood, but a quantitative understanding of the secondary bifu...

An adaptive mesh refinement procedure for wrinkling prediction analyses is presented. First the critical values are determined using Hutchinson’s bifurcation functional. A wrinkling risk factor is then defined and used to determined areas of potential wrinkling risk. Finally, a mesh refinement is operated.