twinning

I am deeply saddened by the passing of Andre Pineau in Paris yesterday. I happened to be one of ~100 PhD students he graduated over the course of his career.

The Advanced Computational Materials Engineering Laboratory (ACME Lab: https://acmelab.ua.edu) in the Department of Mechanical Engineering at The University of Alabama is seeking candidates for a fully-funded PhD position in the area of deformation mechanics to begin August 2022.

Dear Colleagues,

Vaibhav Agrawal, Kaushik Dayal, Carnegie Mellon University
doi: http://dx.doi.org/10.1016/j.jmps.2015.04.010 (part I)
doi: http://dx.doi.org/10.1016/j.jmps.2015.05.001 (part II)

Reversible deformation of metal nanowires accommodating large strains by twinning-detwinning

In situ studies of deformation in metal nanowires have yielded interesting results, as recently published in Nature Communications. An international research team performed cyclic loading on gold nanowires and observed twinning and detwinning phenomena, respectively caused by tensile and compressive loading, and elucidate the underpinning mechanism by molecular dynamics simulations.

Recently accepted for publication in JMPS:

http://www.sciencedirect.com/science/article/pii/S0022509613000884

A postdoctoral position is available in the material science laboratory (SIMAP) of INP Grenoble, France, in David Rodney’s group in collaboration with Laurent Capolungo from Georgia Tech Lorraine, with primary focus on the atomic-scale study of twinning in HCP metals. We are looking for a strongly motivated candidate to apply saddle-point search methods, including the Nudged Elastic Band method and the Activation Relaxation Technique, to study the nucleation and propagation of primary and secondary twins during the plastic deformation of HCP metals.

Adv. Funct. Mater.  DOI: 10.1002/adfm.201101224

The project is based on the well-known size effect exhibited by metals, i.e
the fact that their strengths are greatly enhanced when at least one
microstructural lengthscale is scaled down to the nanometer range or
when the size of the object is restricted to the micron or sub-micron
range. At these scales the interfaces and their associated properties
play a significant role. This project will focus on the effect of
spatial confinement on the three most common deformation mechanisms:
dislocation glide, mechanical twinning and mechanically-induced
martensitic phase transformations; and will be based on the synergies
between physically-based phenomenological modelling using
strain-gradient plasticity at the highest scale, and thorough

We present atomistic simulations of the tensile and compressive loading of single crystal FCC nanowires with <100> and <110> orientations to study the propensity of the nanowires to deform via twinning or slip.  By studying the deformation characteristics of three FCC materials with disparate stacking fault energies (gold, copper and nickel), we find that the deformation mechanisms in