Séminaire IUSTI – 29 nov. 2019 – 11h salle 250

Propagation of defects by passive and active load in systems with micro-inhomogeneities

Nikolay Gorbushin – Institut de Géophysique du Globe, Paris

Microstructure plays important role in material modelling as it brings new insights in understanding of moving defects. Examples include the Peierls stress for dislocations or lattice trapping for cracks which predict the resistance of defect movement in lattices not observed by continuum treatments. Using a bi-stable mass-spring model, it is possible to show that the presence of external vibrational loads can enhance defect propagation. Moreover, if the mechanical system is able to generate active stresses, these defects can move with supersonic speeds without dissipation.