Blog posts

Two solids can adhere to each other in the presence of a liquid bridge between them, which is called wet adhesion. When the solid is soft, the liquid bridge can cause deformation in the material, and in turn, the deformation may have dramatic effects on the wet adhesion. To investigate the effect, in this article, we calculate the deformation in two soft layers with different separations and connected by a liquid bridge. We illustrate the effect of deformation in the soft layers on the adhesive force.

Cavitation can be often observed in soft materials. Most previous studies were focused on cavitation in an elastomer, which is under different mechanical loadings. In this paper, we investigate cavitation in a constrained hydrogel induced by drying. With taking account of surface tension and chemo-mechanics of gels, we calculate the free energy of the system as a function of cavity size. The free energy landscape shows double-well structure, analogous to first-order phase transition.  Above the critical humidity, a cavity inside the gel is tiny.

Dielectric elastomers (DEs) feature nonlinear dynamics resulting from an electromechanical coupling.

Under alternating voltage, the DE resonates with tunable performances. We present an

analysis of the nonlinear dynamics of a DE as electromechanical resonator (DEER) configured as a

pure shear actuator. A theoretical model is developed to characterize the complex performance

under different boundary conditions. Physical mechanisms are presented and discussed. Chaotic

no longer available.

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A postdoctoral position in france is openened on DFT calculations to get the influence of hydrogen on grains boudaries failure in Al polycristals. This work is a between LSPM and ITODYS labs.

Please find the position attached.

Contact:

We are looking for a few postdoctoral researchers to work on the following topics at Nanyang Technological University, Singapore.  

1. First-principles calculation/molecular dynamics simulation of two-dimensional materials for energy and environmental applications.  

2. Numerical modeling of fracture and fatigue behaviors of metallic/polymeric materials.

Dislocations are topological line defects in three-dimensional crystals. Same-sign dislocations repel according to Frank’ s rule . This rule is broken for dislocations in van der Waals (vdW) layers, which possess crystallographic Burgers vector as ordinary dislocations but feature “ surface ripples”  due to the ease of bending and weak vdW adhesion of the atomic layers. We term these line defects “ ripplocations”  in accordance to their dual “ surface ripple”  and “ crystallographic dislocation” characters.

We would like to invite your contribution to Symposium #18: “Experiments and Constitutive Modelling of Materials in Advanced Forming Processes” in the upcoming ASME 2015 Applied Mechanics and Materials Conference, McMAT2015, to be held in Seattle on June 29-July 1, 2015. Please follow the link below to the conference: http://www.asmeconferences.org/mcmat2015/