| Abstract Scope |
The dynamic transmission electron microscope (DTEM) enables in situ multi-frame image acquisitions (i.e., movies) of rapidly evolving solidification fronts with high spatial and temporal resolutions. Here, work will be presented from laser-induced rapid solidification (RS) experiments in Al-based alloys. RS occurs in numerous manufacturing processes involving metallic alloys, such as laser welding and additive manufacturing (AM), and results in processing conditions that produce non-equilibrium microstructures. DTEM allows direct observation of RS microstructure evolution and measurements of kinetics. The effects of solute species and solidification rate on phase selection and morphology will be presented, with complementary in situ heat treatments to assess thermal stability and ex situ postmortem microstructure evaluation. Understanding microstructural evolution and the characteristics that form under various solidification conditions is essential for the development of multiscale, experimentally informed predictive modeling, highlighted here by solidification simulations that utilize the in situ measurements from DTEM experiments. |