Alladi Ramakrishnan Hall

Concerning pleats and slip: Do we have a new perspective on plastic deformation?

Surajit Sengupta

TCIS-TIFR, Hyderabad

Customarily, initiation of plastic deformation or yielding of a crystal is explained as a non-equilibrium transition mediated by complex, many-body interactions among dislocations. We offer a different viewpoint, where yielding becomes a dynamical transition associated with an equilibrium phase transition from a crystal with predominately affine to one with mostly non-affine displacements. This represents a conceptual advance in understanding yielding using non-affineness, a notion more generally useful than dislocations. As a consequence of this perspective, we propose a method for accurately predicting the yield point. Our idea can also be used to develop protocols, which tailor the yield point of colloidal crystals using dynamic laser traps.