Microstructural evolutions in metallic alloys submitted to irradiation

The irradiation of materials by energetic particles can lead to the formation of non-equilibrium phases and microstructures. The extrapolation to new alloys and to new types of irradiation of the experimental data available nowadays stays nevertheless problematic. This difficulty is due in part to the wide time and space ranges taken into account from Angstrom to picosecond for the elementary damage processes and the crystal defects diffusion, until beyond the millimeter and the second for the mechanical properties. Moreover, the irradiation dynamical forcing of these materials leads to a change of the microstructure evolution. A brief outlook of the concept of dynamic equilibrium phase diagram is presented as well as its experimental determination, by modeling or by atomic scale simulation. It is shown too that the introduction of new space ranges by displacement cascades can lead to the auto-organization of the composition field and of chemical parameter in metallic alloys. (O.M.)