Wahn, M.; Neugebauer, J.: Generalized Wannier functions: An efficient way to construct ab-initio tight-binding parameters for group-III nitrides. Physica Status Solidi B: Basic Research 243, 7, pp. 1583 - 1587 (2006)
Marquardt, O.; Wahn, M.; Lymperakis, L.; Hickel, T.; Neugebauer, J.: Implementation and application of a multi-scale approach to electronic properties of group III-nitride based semiconductor nanostructures. Workshop on Nitride Based Nanostructures, Berlin, Germany (2007)
Neugebauer, J.; Wahn, M.: Exact exchange within Kohn-Sham formalism. Standard and variational approach. 1. Harzer Ab initio Workshop, Clausthal-Zellerfeld (2006)
Wahn, M.; Neugebauer, J.: The Bandgaps of GaN and InN in Zinc-blende and Wurtzite Phase: DFT Calculations Using the Exact Exchange (EXX) Functional. Workshop Forschergruppe Bremen, Bad Bederkesa, Germany (2005)
Wahn, M.; Neugebauer, J.: Generalized Wannier functions: An accurate and efficient way to construct ab-initio tight-binding orbitals. DPG-Tagung, Berlin, Germany (2005)
Wahn, M.; Neugebauer, J.: Generalized Wannier Functions: An efficient way to construct ab-initio tight-binding orbitals for group-III nitrides. 6th International Conference on Nitride Semiconductors, Bremen, Germany (2005)
Hydrogen in aluminium can cause embrittlement and critical failure. However, the behaviour of hydrogen in aluminium was not yet understood. Scientists at the Max-Planck-Institut für Eisenforschung were able to locate hydrogen inside aluminium’s microstructure and designed strategies to trap the hydrogen atoms inside the microstructure. This can…
We will investigate the electrothermomechanical response of individual metallic nanowires as a function of microstructural interfaces from the growth processes. This will be accomplished using in situ SEM 4-point probe-based electrical resistivity measurements and 2-point probe-based impedance measurements, as a function of mechanical strain and…
Hydrogen induced embrittlement of metals is one of the long standing unresolved problems in Materials Science. A hierarchical multiscale approach is used to investigate the underlying atomistic mechanisms.
Hydrogen embrittlement affects high-strength ferrite/martensite dual-phase (DP) steels. The associated micromechanisms which lead to failure have not been fully clarified yet. Here we present a quantitative micromechanical analysis of the microstructural damage phenomena in a model DP steel in the presence of hydrogen.
This project will aim at developing MEMS based nanoforce sensors with capacitive sensing capabilities. The nanoforce sensors will be further incorporated with in situ SEM and TEM small scale testing systems, for allowing simultaneous visualization of the deformation process during mechanical tests
The project aims to study corrosion, a detrimental process with an enormous impact on global economy, by combining denstiy-functional theory calculations with thermodynamic concepts.
Understanding hydrogen-assisted embrittlement of advanced structural materials is essential for enabling future hydrogen-based energy industries. A crucially important phenomenon in this context is the delayed fracture in high-strength structural materials. Factors affecting the hydrogen embrittlement are the hydrogen content,...
Understanding hydrogen-assisted embrittlement of advanced high-strength steels is decisive for their application in automotive industry. Ab initio simulations have been employed in studying the hydrogen trapping of Cr/Mn containing iron carbides and the implication for hydrogen embrittlement.
Nickel-based alloys are a particularly interesting class of materials due to their specific properties such as high-temperature strength, low-temperature ductility and toughness, oxidation resistance, hot-corrosion resistance, and weldability, becoming potential candidates for high-performance components that require corrosion resistance and good…