Search results for "Wrinkling"

Deep drawing process parameter design: a multi objective optimization approach

2009

Buckling of a coating strip of finite width bonded to elastic half-space

2008

AbstractA solution for buckling of a stiff strip of finite width bonded to a compliant elastic half-space and subjected to uniform axial compression is presented. Approximate semi-analytical and finite element solutions are obtained and compared with a two-dimensional case of a plate on elastic foundation. The comparison demonstrates that the two-dimensional solution can be applied to predict the buckling wavelength and critical compressive strain when the width of the strip is equal to or larger than the buckling wavelength. For narrow strips, the wavelength is smaller and critical strain is higher than that of a plate on foundation.

Process parameters calibration in 3D tube hydroforming processes

2007

In tube hydroforming the concurrent actions of pressurized fluid and mechanical feeding allow to obtain tube shapes characterized by complex geometries such as different diameters sections and/or bulged zones. What is crucial in such processes is the proper design of operative parameters aimed to avoid defects (for instance shape defects or ductile fractures). The main process parameters are material feeding history (i.e. the punches velocity history) and internal pressure path during the process. In more complex three dimensional processes, also the action of a counterpunch is generally useful to reduce thinning in particular in expansion zones of the tube (i.e. T or Y shaped tubes). The g…

A 3D Cohesive interface for the delamination analysis of a stiff film on a soft elastic substrate and the wrinkling/buckling deformation modes

2018

The paper proposes a finite element systematic study of a mechanical system composed by a soft elastic substrate, subjected to a uniform state of compression, covered by a stiff thin film. This kind of problem is rather common for coating systems where layered materials with severe mismatch of elastic and thermal properties are largely employed. The specific mechanical problem stands on the concomitant competition between elastic wrinkling surface deformation and the nonlinear delamination that can develop at the interface between the thin film and the substrate. Both mechanical phenomena have their source in the nonlinear elastic buckling of the thin stiff film, which can be viewed as a th…