Electron Microscopy and X-Ray Diffraction

(Dr. rer. nat. Christoph Somsen)

The use of X-ray diffraction and scanning electron microscopy (SEM) allows (i) for the identification of crystalline substances and the volume fractions of phases in multiphase materials, (ii) for the determination of textures (e.g. textures associated with solidification processes and thermomechanical treatments) and (iii) for imaging, chemically analysing and crystallographically identifying small particles (e.g. carbides). SEM also enables the study of rupture surfaces to identify the origin of material failures. In both methods, SEM and X-ray analysis, the interaction of particle waves with crystals plays a key role. The lecture covers the physical background of different types of SEM contrasts and provides an introduction to one of the key methods for local chemical analysis in the SEM, the energy dispersive spectroscopy of X-rays. In the X-ray part of the lecture, the well-established standard methods are presented (Laue method, internal stresses measurement and texture analysis). During a visit to an SEM and a state-of-the-art X-ray diffractometer in the laboratory of the Institute for Materials students come into first direct contact with these two key methods for materials characterization.

The lecture is held in the summer semester on Thursdays from 1:00 to 4:00 pm.

Lecture Announcement SS23

ROEREM SoSe-23.pdf