Materials exposed to nuclear reactor environments have their microstructure and therefore properties continuously changing under the impact of high temperature, irradiation, corrosion and mechanical stress happening all at once. The microstructure evolution of nuclear materials is thus a dynamic process where atomic displacements occur continuously due to irradiation, diffusion processes happen due to high operating temperatures, dislocation dynamics happen due to mechanical stress and corrosion builds up and dissolution occurs due to the corrosive environment.

Due to the dynamic nature of these phenomena, in situ experiments are often useful, if not necessary, to understand the processes at play because they allow observation during exposure to track the response of the material in real time under irradiation, annealing, straining and their coupling.

For each process of interest, an in situ characterization technique may be more adapted than others. The goal of this symposium is to gather the material science community involved with in situ experiments that allow for the characterization of the microstructure and property evolution of nuclear materials in general, to discuss the perks and limitation of each technique, as well as their complementarity, and the state of the art. It is also the intent of this symposium to include how in situ experiments are used for benchmarking of models developed computationally.

in situ nuclear materials operando radiation effects scanning electron microscopy (SEM) scanning transmission electron microscopy (STEM) transmission electron microscopy (TEM) x-ray diffraction (XRD) x-ray tomography