Geometry and mechanics of thin growing bilayers
Matteo Pezzulla, Gabriel P. Smith, Paola Nardinocchi, and Douglas P. Holmes, Soft Matter, 12, 4435-4442, (2016).
research
Funded PhD studentship: Modelling of Fibroblast Mechanobiology
Supervisor: PN Watton, Department of Computer Science, University of Sheffield.
Co-supervisors: Prof Ray Ogden, School of Mathematics and Statistics & Dr Huabing Yin, Bioengineering, University of Glasgow
We are seeking applications from motivated mathematics, science or engineering graduates with strong mathematical/computational modelling skills interested in studying for a Ph.D. in an exciting interdisciplinary environment.
Harnessing atomistic simulations to predict the rate at which dislocations overcome obstacles
Predicting the rate at which dislocations overcome obstacles is key to understanding the microscopic features that govern the plastic flow of modern alloys. In this spirit, the current manuscript examines the rate at which an edge dislocation overcomes an obstacle in aluminum. Predictions were made using different popular variants of Harmonic Transition State Theory (HTST) and compared to those of direct Molecular Dynamics (MD) simulations. The HTST predictions were found to be grossly inaccurate due to the large entropy barrier associated with the dislocation–obstacle interaction.
Continuous and discrete microstructured materials with null Poisson's ratio
In this paper we propose diff erent classes of isotropic microstructured media with tunable Poisson's ratio. The elastic periodic systems are continuous porous media and two- and three-dimensional lattices. The microstructural parameters can be tuned in order to have an eff ective Poisson's ratio equal to zero. The connection between microstructural parameters and eff ective properties is shown in detail both analytically and numerically.
Continuous system with null Poisson's ratio:
Design of a porous material with isotropic negative Poisson's ratio
This paper proposes the design of a two-dimensional porous solid with omnidirectional negative Poisson's ratio. The hexagonal periodic distribution of the pores makes the e ffective behavior isotropic. Both experimental tests and numerical simulations have been performed to determine the e ffective properties of the porous solid. A parametric study on the e ffect of the geometrical microstructural parameters is also presented. This auxetic structure is easy to fabricate and can be very useful in several engineering applications.
Journal Club Theme of May 2016: Recent Progress in Curvilinear Electronics and Mechanics
Recent Progress in Curvilinear Electronics and Mechanics
Jianliang Xiao
Department of Mechanical Engineering, University of Colorado Boulder
1. Introduction
Quantifying dislocation microstructure evolution and cyclic hardening in fatigued face-centered cubic single crystals
Discrete dislocation dynamics simulations were performed to investigate the dislocation microstructure evolution and cyclic hardening during the early stages of fatigue loading in nickel single crystals. The effects of the crystal size and initial dislocation densities on both the mechanical response and the evolution of dislocation microstructure were quantified. Crystals having an initial dislocation density of 1012 m−2 and diameter less than do not show any dislocation density multiplication or cyclic hardening.
Line Spring elements errors
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***Problem ***
Failure pressure for Steam generator tube having 2 axial cracks. I am following one paper in that paper they found failure pressure by finding J and K values for line spring elements for different pressure. The pressure at which it approach material JIC(92N/mm) and KIC(65Mpa*sqrt(m)) value is considered as failure pressure or coalescence pressus
**Modelling**
Universal Scaling Laws for Homogeneous Dislocation Nucleation During Nanoindentation
Akanksha Garg, Craig Maloney
(accepted mannuscript in Journal of Mechanics and Physics of Solids)