[Back]

G. Requena:
"Time-resolved studies of engineering materials using hard X-rays";
Keynote Lecture: Materials Science, Imaging and Dynamics at XFEL.EU, Hamburg - Deutschland (invited); 12-10-2012 - 12-11-2012.

Engineering components are designed exploiting the properties of materials, which, in most of the cases, are formed by more than one microstructural phase. The property profiles of multiphase materials are determined by the combination of the properties of the individual phases and the three-dimensional architecture formed by them, which is given by their proportion, size, morphology and spatial arrangement. Thus, the thermo-mechanical behaviour of multiphase metallic materials is determined by the mechanical and physical properties of the microstructural phases, their thermal/mechanical stability, deformation behaviour and geometrical arrangement. All these parameters may vary during production and service of the materials and, therefore, physical aspects such as nucleation and growth of phases, diffusion controlled morphological changes, bonding of interfaces, deformation mechanisms and damage formation/evolution must be considered. The sensitivity of the thermo-mechanical properties of engineering metallic materials to microstructural changes has been extensively studied and reported but new insights have been gained in the last years due to the advance of modern characterisation methods that allow to observe in situ the evolution of the microstructure. In this talk, examples in which the use of synchrotron-based imaging and diffraction are being decisive to resolve time-dependent mechanisms in engineering metallic materials will be presented. Particularly, advances in the understanding of solidification processes, damage formation and evolution and high temperature deformation mechanisms in alloys and composites will be considered. Special emphasis will be given to the time-resolution achievable during in situ X-ray tomography and diffraction in terms of current capabilities, constraints and future opportunities in case of further improvement.