Il seminario si svolge martedì 23 aprile, presso la sede CNR-IAC di Roma, aula I piano, in modalità mista, presenza e streaming (vedi link in calce).
Il titolo del seminario è: Asymptotic analysis of some semi-discrete models for crystal plasticity.
Di seguito l'abstract.
In this talk we discuss some semi-discrete models for plastic deformations in metals involving the presence of a large number of dislocations. Dislocations are a particular type of defect to the ordered atomic structure of crystalline materials like metals, and their presence and motion in the bulk plays a fundamental role in plastic deformations of the material. Semi-discrete models have been introduced in this context as an analytical tool to study dislocations' effect in metal plasticity. These models are characterized by a hybrid nature: while framed in a continuum setting they retain some of the discrete features typical of dislocations. In particular these models are characterized by energies that depend on a small parameter, proportional to the characteristic length of the crystal lattice. In certain energetic regimes the asymptotic analysis of such energies allows to derive effective energies for plastic deformation. In particular we will focus on the so-called logarithmic regime at which the asymptotic analysis yields in the limit a line tension energy for dislocations. We will then study a rescaled version of such energy and derive, in the sense of Gamma-convergence, a macroscopic plastic energy accounting for possibly diffused dislocations' density.
