3. Plastic flows

3.1 Temporal and spatial heterogeneity of plastic flows

Experience has shown that plastic flows in high-purity single crystals are complex dynamic phenomena that result in heterogeneities in the spatial distribution of both strain and stress. These heterogeneities manifest themselves on several scales: dislocation line, slip line, slip band. Time scales also vary considerably, from one type of defect or stress to another.

The situation is even more complex for polycrystalline samples with or without inclusions. We are dealing here with a heterogeneous system made up of crystals of different orientation and/or structure and/or composition. Over the past forty years or so, we have seen the development of polyphase or composite materials, such as nickel-based superalloys...