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PhD Studentship: In-situ quantification of interphase stress during martensitic transformations, Open University, UK

Submitted by RichardMoat_OU on

Fully funded PhD studentship at The Open Univeristy campus, Milton Keynes, UK. The aim of this project is to optimise experimental techniques such as digital image correlation (DIC) and focused ion beam (FIB) hole drilling to investigate the micro scale stresses and strains occurring during martensitic transformations. The techniques will be applied to a range of materials from simple steels to complex shape memory alloys. There will also be scope within the project to study martensitic alloys using central facilities such as the ILL, ESRF and Diamond light source.



Direct influence of residual stress on the bending stiffness of cantilever beams

Submitted by Bin Liu on

Although the cantilever beam has been widely used as a sensor to measure various physical quantities, important issues such as how residual stress affects its bending stiffness and what are the underlying physical origins have not been fully understood. We perform both theoretical analyses and finite-element simulations to demonstrate for the first time that without changing the material tangent stiffness, residual stress within the beam can directly influence the bending stiffness of the beam. This direct influence arises from two origins: geometry nonlinearity and Poisson’s ratio effect.

Dislocation Climb in Two-Dimensional Discrete Dislocation Dynamics

Submitted by Kamyar M Davoudi on

In this paper, dislocation climb is incorporated in a two-dimensional discrete dislocation dynamics model. Calculations are carried out for polycrystalline thin films, passivated on one or both surfaces. Climb allows dislocations to escape from dislocation pile-ups and reduces the strain-hardening rate, especially for fully passivated films. Within the framework of this model, climb modifies the dislocation structures that develop during plastic deformation and results in the formation of pile-ups on slip planes that do not contain any dislocation sources.

Vibration of wavy single-walled carbon nanotubes based on nonlocal Euler Bernoulli and Timoshenko models

Submitted by Payam Soltani on

Vibration of wavy single-walled carbon nanotubes based on nonlocal Euler Bernoulli and Timoshenko models

By: Payam SoltaniA KassaeiM M Taherian and A Farshidianfar

Fatigue of polymer-supported Ag thin films

Submitted by Gi-Dong Sim on

The fatigue behavior of Ag films on polyethyleneterephthalate substrates was studied using electrical resistance measurements.
Scanning electron microscopy images showed two types of failure: typical fatigue failure with extrusion–intrusion pairs, and ductile
failure with local necking. Once through-thickness cracks are formed in the metal layer, cracks propagate and the resistance increases abruptly for both failure modes. The effect of adhesion on fatigue life is discussed in terms of concurrent delamination, crack initiation and propagation.

Improving the stretchability of as-deposited Ag coatings on poly-ethylene-terephthalate substrates

Submitted by Gi-Dong Sim on

In this paper, we report that silver films evaporated on poly-ethylene-terephthalate (PET) substrates coated with an acrylic primer can be stretched beyond 70% without fracture. As-deposited films show a larger failure strain than annealed coatings. These observations are rationalized in light of a ductile fracture mechanism where debonding from the substrate coevolves with strain localization. The results of this study indicate that PET substrates coated with an acrylic primer layer may be suitable for stretchable electronics.

How to set boundary conditions for Transport Equation with closed boundary?

Submitted by dolken on

Hi Everyone,

 I have a modeling problem.  It finally goes to drug flows inside a tute of one dimension. The speed of the drug flow is constant. The initial condition is know. The tube is closed, which means no exterior drug flows into the tube and the drug can not flow outside of the tube. Does anyone know how to set up the boundary conditions in mathematical formula? Thanks a lot.

PhD position in nano-/micro mechanics

Submitted by pooria pasbakhsh on

 One PhD student position is available at Monash University, Sunway Campus in Malaysia with the leadership of Prof A.K Soh. 

 We expect students with the knowledge and experience in at least two or more of the following skills:



1. nano-/micro-mechanics.

2. computational mechanics.

3. fabrication and characterization of advanced materials, e.g.nano-thin-films, nano-wire arrays, functional materials, etc.

4. strong physics/chemistry knowledge, e.g., quantum mechanics.