In situ study on dendrite growth of metallic alloy by a synchrotron radiation imaging technology

This study was trying to observe the real-time dendrite growth of Sn-Bi and Sn-Pb binary alloys by a synchrotron radiation imaging technology. The imaging system includes an intense and high brightness synchrotron radiation source, a high-resolution and fast-readout charge coupled device camera, an alloy sample and a Bridgman solidification system. The imaging experiments were done at Beijing Synchrotron Radiation Facility with an updated synchrotron radiation imaging technique, diffraction-enhanced imaging, which was firstly used to study the dendrite growth of metallic alloy. A series of growth behavior and morphology evolution of dendrite have been in situ observed, such as columnar-to-equiaxed transition, dendrite competition, dendrite fragmentation and floating, etc., which can offer the direct proofs to verify or improve the solidification theories of metallic alloy. This research opens a novel window for the study of alloy solidification and enables the unambiguous understanding of solidification processes in optically opaque, metallic alloys.