Abstract:

Grain boundaries (GB) are generally considered as static obstacles to dislocations and sinks for point defects and their clusters. But, in fact, the processes that take place at GBs is more complex and can reveal properties directly related to plasticity phenomena that go beyond the interaction with a static barrier. The atomic level description of GB line defects and their interaction with crystal dislocations allows to understand important processes such as slip transmission in polycrystalline materials and shear-coupled GB migration. The description of (10-12) twin boundary in hcp-Mg and the (112) tilt GB in bcc-Fe will be taken as examples.