X-ray tomoscopy in materials and processing science

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Application of time-resolved tomography with acquisition rates above 25 per second (called tomoscopy in the following) in conjunction with simultaneous diffraction is proposed as a method to solve urgent scientific questions related to rapid changes in metallic systems. We aim at: (i) Understanding the foaming process of aluminium alloys by revealing details of bubble nucleation, growth, inter-bubble diffusion and subsequent foam degradation, (ii) Investigating dendrite, intermetallic and pore formation in casting alloys during solidification at industrial cooling rates, (iii) Gaining knowledge about the phenomena in the zone of influence of a laser as alloys are welded and cut or powders are laser-sintered in a typical 3D printing process. To carry out such experiments we design and build sample environments allowing for investigating samples in-situ under defined conditions (heating, melting, protective gas environment, etc.) while they are rotated at up to 6000 rpm and X-ray radiographs (projections) are continuously acquired to reconstruct up to 200 full tomograms every second. Furthermore, we develop tools to process the vast amount of image data recorded and to allow for automated tomographic reconstruction and image analysis (quantitative phase analysis, tracking of individual structural features, etc.).