In-situ diffraction studies related to thermo-mechanical processes in metals and alloys

Abstract

Both neutron and synchrotron high-energy X-rays have penetrating power into metals, and intensities are competitive for ex- and in-situ studies of thermo-mechanical processes. They bear great potential in order to speed up materials design by orders of magnitude. The present contribution will enhance novel pioneering experiments on selected metal systems and showcase the complementarity between neutrons and X-rays and to other in-situ techniques, such as the Laser Confocal Scanning Microscope. Neutrons bear the advantage of averaging over larger volumes and therefore, are less dependent on grain statistics, leading to good, quantitative phase analysis and texture measurements. Phase evolutions are studied upon application of high temperature and high pressure. The neutron contrast, different to X-rays has been employed to investigate order-disorder transitions in titanium-aluminides. Moreover, dynamical theory of diffraction leads to the study of the smallest distortions and their kinetics at high temperature in zirconium and titanium alloys. Synchrotron X-rays allow t focusing on a small number of crystallites, showing up traces of grain evolution in reciprocal space, such as grain rotation, grain growth, phase correlations, dynamic recovery and decrystallization such as in a Materials Oscilloscope.