Lymperakis, L.; Neugebauer, J.: Thermodynamics and adatom kinetics of non-polar GaN surfaces. Spring meeting of the German Physical Society (DPG), Berlin, Germany (2008)
Petrov, M.; Lymperakis, L.; Neugebauer, J.; Stefaniuk, R.; Dluzewski, P.: Nonlinear Elastic Effects in Group III-Nitrides: From ab-initio to Finite Element Calculation. 17th International Conference on Computer Methods in Mechanics CMM-2007, Spala, Poland (2007)
Petrov, M.; Lymperakis, L.; Neugebauer, J.; Stefaniuk, R.; Dluzewski, P.: Nonlinear Elastic Effects in Group III-Nitrides: From ab-initio to Finite Element Calculation. 17th International Conference on Computer Methods in Mechanics CMM-2007, Spala, Poland (2007)
Lymperakis, L.; Neugebauer, J.: Ab-initio based multiscale analysis of the 5D configurational space of Grain Boundaries in Aluminum. Spring meeting of the German Physical Society (DPG), Regensburg, Germany (2007)
Petrov, M.; Lymperakis, L.; Neugebauer, J.: Nonlinear Elastic Effects in Group III-Nitrides. Spring meeting of the German Physical Society (DPG), Regensburg, Germany (2007)
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)
Lymperakis, L.: Ab-initio based multiscale caclulations of Grain Boundaries in aluminum. 1. Harzer Ab initio Workshop, Clausthal-Zellerfeld, Germany (2006)
Lymperakis, L.; Neugebauer, J.: Kinetically stabilized ordering in AlGaN alloys. Institute of Fundamental Technological Research, Polish Academy of Sciences, Colloquium, Warsaw/Poland (2006)
Lymperakis, L.; Neugebauer, J.: Ab-initio based multiscale calculations of low-angle grain boundaries in Aluminum. DPG spring meeting, Dresden, Germany (2006)
Lymperakis, L.: Ab-initio based multiscale calculations of extended defects in condensed matter. Ab initio Description of Iron and Steel (ADIS2006), Ringberg Castle (2006)
Lymperakis, L.; Neugebauer, J.: Electronic properties of non-stoichiometric dislocation cores in GaN. Materials Research Society fall meeting, Boston, MA, USA (2005)
Lymperakis, L.; Neugebauer, J.: The role of strain fields, core structure, and native defects on the electrical activity of dislocations in GaN. The 6th International Conference on Nitride Semiconductors, Bremen (2005)
Lymperakis, L.; Neugebauer, J.: Formation of steps and vicinal surfaces on GaN (0001) surfaces: Implications on surface morphologies and surface roughening. DPG spring meeting, Berlin, Germany (2005)
Duff, A.; Lymperakis, L.; Neugebauer, J.: Limits of Indium Incorporation on In1-xGaxN {0001} III- and N-Polar Surfaces: An Ab Initio Approach. 10th International Conference on Nitride Semiconductors, Washigton DC, USA (2013)
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…
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.
For understanding the underlying hydrogen embrittlement mechanism in transformation-induced plasticity steels, the process of damage evolution in a model austenite/martensite dual-phase microstructure following hydrogenation was investigated through multi-scale electron channelling contrast imaging and in situ optical microscopy.
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…
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.
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
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,...
Thermo-chemo-mechanical interactions due to thermally activated and/or mechanically induced processes govern the constitutive behaviour of metallic alloys during production and in service. Understanding these mechanisms and their influence on the material behaviour is of very high relevance for designing new alloys and corresponding…