twinning

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