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A Special Issue of Engineering Fracture Mechanics

on

"Fracture and contact mechanics for interface problems", edited by Marco Paggi, Alberto Carpinteri and Peter Wriggers has just been published:

http://www.sciencedirect.com/science/journal/00137944/80

The selected articles were presented in a Minisymposium of the IV European Conference on Computational Mechanics, Paris, France, 2010.

Far greater voltage-actuated deformation is achievable for a dielectric elastomer under equal-biaxial dead load than under rigid constraint usually employed. Areal strains of 488% are demonstrated. The dead load suppresses electric breakdown, enabling the elastomer to survive the snap-through electromechanical instability. The breakdown voltage is found to increase with the voltage ramp rate. A nonlinear model for viscoelastic dielectric elastomers is developed and shown to be consistent with the experimental observations. 

Published Online:

The dielectric constant of elastomeric dielectric material is an
essential physical parameter, whose value may affect the
electromechanical deformation of a dielectric elastomer actuator. Since
the dielectric constant is influenced by several external factors as
reported before, and no certain value has been confirmed to our
knowledge, in the present paper, on the basis of systematical comparison
of recent past literature, we conducted extensive works on the
measurement of dielectric properties of VHB films, involving five
influencing factors: prestretch (both equal and unequal biaxial),
electrical frequency, electrode material, stress relaxation time and
temperature. Experimental results directly show that the dielectric

i'need to  initial geometric imperfection of a localized buckling behavior of unstiffened thin plate will be analyzed. Code Abaqus finite element analysis can be used for this purpose. Since a default is not always in isolation, the interaction between several localized defects will be considered. A parametric study will be conducted on the effect due to the interaction by using an experimental and numerical analysis of variance.

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