Radial Cracks in Perforated Thin Sheets

Radial cracks in perforated thin sheets.

When a rigid cone is slowly pushed through a thin elastic sheet, the material breaks, exhibiting a network of cracks expanding in the radial direction. Experiments conducted with aluminum sheets show that the number of cracks is selected at the beginning of the perforation process and then remains stable. A simple model predicts the number of cracks as the result of a competition between the el...

Stress intensity factor of mode-III cracks in thin sheets.

The stress field at the tip of a crack of a thin plate of elastic material that is broken due to a mode III shear tearing has a universal form with a nonuniversal amplitude, known as the stress intensity factor, which depends on the crack length and the boundary conditions. We present in this paper exact analytic results for this stress intensity factor, thus enriching the small number of exact...

Cracks in thin sheets: when geometry rules the fracture path.

We study the propagation of brittle fractures coupled to large out-of-plane bending, as when a brittle elastic thin sheet is cut by a moving object. Taking into account the separation of the film's bending and stretching energies and using fracture theory we show that such cracks propagate according to a simple set of geometrical rules in the limit of small thickness. In particular, this provid...

Experimental Studies of Wave Transmission through Single Perforated Sheets and Upright Perforated Wave Filters

Localized Necking in Thin Sheets

SIJMMARY BY USING a simplified constitutive model of a pointed vertex on subsequent yield loci, namely, such that the equations of deformation-theory of rigid-plastic solids apply for fully-active stress increments, the onset of localized necking under biaxial stretching has been predicted. The predictions agree reasonably well with reported experimental observations. Since localized necking un...