One important task of materials science is to determine the relationship between microstructure and the resulting properties.

To obtain a fundamental knowledge it is therefore necessary to characterize materials down to the atomic level. The applied methods range from light microscopy and X-ray diffraction, to scanning electron microscopy, transmission electron microscopy, small-angle neutron scattering and atom probe measurements. By combining these measurements a length scale from the µm-level down to the atomic level is covered. This allows to determine and understand the internal structure of materials and their properties.

Research Areas:

Interface structure determination
Internal interfaces can determine materials properties (electronic, mechanical …). It is therefore important to study their structure down to the atomic scale by using e.g. high-resolution transmission electron microscopy (TEM). Of particular interest is which type of interfaces occur in polycrystalline materials and how their structure looks like (atomically abrupt, reaction phase formation, special grain boundaries …).

Electron energy-loss near edge structure investigations
Electron energy-loss spectroscopy (EELS) performed in the TEM can be used to determine the chemical composition of e.g. nano-sized particles. In addition, studying the electron energy loss near-edge structure allows obtaining information on the electronic structure, valence state and coordination. Such studies are performed for example in nano-structured materials.

TEM studies
In applied materials such as steels it is important to understand which microstructural features are determining the thermo-mechanical properties. In several research studies we are analyzing e.g. the type and spatial arrangement of precipitates, dislocation densities and correlate the results to the mechanical test data.

Bright field TEM image shows grain boundaries and precipitates in a steel after creep.

Complementary methods
The aim is to investigate how the combination of different characterization techniques such as small angle scattering experiments, X-ray diffraction techniques, electron microscopy and atom probe analyses can be used to obtain not only a qualitative but also a quantitative description of e.g. precipitation state.