|About this Abstract
||2019 TMS Annual Meeting & Exhibition
||Solidification Processing of Light Metals and Alloys: An MPMD Symposium in Honor of David StJohn
||Measurements of Microstructure Evolution and Kinetics during Laser-induced Rapid Solidification of Al-based Alloys
||Joseph McKeown, John D. Roehling, Seth Griffiths, Kai Zweiacker, Amy J. Clarke, Christian Leinenbach, Jörg Wiezorek, Manyalibo J. Matthews
|On-Site Speaker (Planned)
Microstructure formation under rapid solidification (RS) conditions depends strongly on heat and solute transport phenomena at the solid-liquid interface, where large driving forces and transformation rates complicate control and prediction of resultant microstructures. Validated models to describe non-steady-state transients at the solid-liquid interface under RS conditions are lacking, largely due to the inability to capture these non-equilibrium solidification fronts in situ as the microstructure evolves. Here, we present work focused on microstructure evolution and solidification kinetics in Al-based alloys under laser-induced RS processing conditions (large thermal gradients, high cooling rates and solidification front velocities) using time-resolved in situ imaging by dynamic transmission electron microscopy (DTEM). The effects of solute species (Cu, Si, Ge, Ce, Zr), temperature gradient, and solidification rate on phase selection and morphology are explored. Complementary ex situ solidification experiments and postmortem microstructure evaluation will also be presented.