X-Ray Tomoscopy: Time-resolved imaging of dynamic processes in materials
The continuous acquisition of tomographic (3D) images, also called tomoscopy, to observe the evolution of altering structures, is an increasingly important method to gain insight into dynamic phenomena in many different areas of materials science and other disciplines. The variety of systems that can be investigated with this method covers a wide dynamic range reaching down to the 1 ms scale. The high fluxes of modern synchrotron x-ray sources in combination with new detectors and efficient data processing make it possible to record several hundred tomograms per second over a period of minutes in order to observe and understand processes in full length and yet in detail.
We show the principles of the method and some selected results of recently performed experiments at the TOMCAT beamline of the Swiss Light Source synchrotron facility in Villigen, Switzerland. The case studies cover various systems: The evolution of liquid metal foams, which extend the knowledge about the gas bubble formation and the ageing of the liquid foam structure. Solidification phenomena in Al alloys at application-oriented cooling rates, which give us knowledge about the microstructure formation and defect generation of the final casting structure. And the investigation of laser powder bed fusion processing to gain real-time insight into the additive manufacturing process.