Time-resolved direct-beam X-ray imaging, with intense, coherent, and monochromatic third-generation synchrotron radiation, and a high-resolution fast-readout detector system have been used for in-situ studies of dendritic and eutectic growth processes in Al-Cu alloys. Temporal and spatial resolutions down to 0.25 seconds and 2.5 m, respectively, were obtained with a field of view up to 1.4 ϫ 1.4 mm 2 . Solid-liquid interfaces and various phase-specific segregates could be observed, and their dynamics could be traced in a sequence of temporally resolved images formed by phase and amplitude contrast from the sample. This article does not present any detailed analysis of a specific solidification phenomenon; instead, it presents to the scientific community an innovative technique for in-situ monitoring of such a phenomenon in real metallic systems.

Sample cells for applying an electric field on the sample during synchrotron X‐ray diffraction experiments have been designed and built, both for small single crystals in an arbitrary orientation and for thin films. For the former type of sample, the cell also includes equipment for control of relative humidity and temperature. Cells of different design have been used successfully with single crystals of two distinct phases of the organic ferroelectric Rochelle salt and in studies of epitaxial thin films of ferroelectric PbTiO3 on a SrTiO3 substrate under weak electric fields.