We investigate solidification of an Al-Al2Cu as a model system to understand the emergence patterns (such lamellar, rod and maze-like) within eutectic colonies. To uncover morphological transitions in-situ in 3D, we introduce here new synchrotron-based, X-ray imaging procedure. Our method simultaneously maximizes temporal (200 ms) spatial resolution ($0.69^2 \mu m^2/pixel$) over that traditiona...

The study of convective motions produced by unstable density distributions in a fluid is now highly developed. Most attention has been given to the case of a thin horizontal layer of fluid, heated below and cooled above, and results obtained using a combination of Boussinesq theory and laboratory experiments have been success­ fully applied in many contexts (Chandrasekhar 1961, Spiegel 1971). T...