An in situ visualization system using synchrotron white X-rays to investigate the solidification behaviors of metallic materials.

An advanced imaging platform has been developed to study the microstructural solidification behaviors of metals using synchrotron white X-rays. This system provides submicrometre effective pixel size and a frame rate of thousands per second, enabling high-resolution and high-speed imaging. The system functions independently, facilitating convenient alignment, magnification adjustments, and precise control of the region of interest. Additionally, we designed a specialized furnace for in situ characterization of microstructures during melting and solidification of metallic specimens at high temperature. This furnace meets stringent optical requirements and allows for finely adjusted specimen temperature gradients through the configuration of heating elements and individual current control. The furnace supports stable high-temperature experiments under vacuum, in an argon atmosphere, and at ambient pressure. Using this advanced imaging system, we investigated real-time in situ solidification phenomena of various metallic materials and other solidifying systems such as silicon. We performed image analysis to quantitatively assess microstructural changes, calculate dendritic spacing and determine liquid fractions.