In-situ 3D X-ray investigation of ceramic powder sintering at the particle length-scale

International audience ; We report an in-situ investigation of a high-temperature ceramic powder sintering performed for the first time at the particle length-scale. This was made possible by the phase-contrast X-ray nano-holotomography technique at the ID16B nano-analysis beamline of the European Synchrotron Radiation Facility (ESRF), featuring nanometer resolution (25 nm) capabilities. To perform sintering inside the synchrotron hutch, a compact high-temperature furnace was designed and developed. The sequence of real-time 3D images captured the collective behavior of the particles as well as the local-level specificities. A list of sintering indicators corresponding to the evolution of the particle shape, particle size, inter-particle neck size, pore size and pore curvature were extracted. The effect of these parameters on densification and their influence on the overall microstructural development were analyzed. Our results demonstrate the potential of synchrotron-based X-ray nano-tomography for studying complex sintering phenomena in 3D.