Helmholtz-Zentrum Geesthacht, Tuesday, 22-May-2012 20:42:33 CEST
http://www.hzg.de/program/materials_systems/core/jaiolwsm/fundamentals/index.html.en

Fundamentals

The understanding of the fundamentals of deformation, damage, and fracture of light-weight materials is essential to control and predict the mechanical properties of light-weight structures as the product of complex production and joining processes. To this end, new micromechanical testing methods will provide important information on the mechanical properties of small volumes on a micro-scale for process development and as input for a micromechanically based constitutive modelling. Transferred to a macroscopic scale this yields phenomenological models for understanding the texture-dependent deformation mechanisms in polycrystals. A lifetime prediction of Mg-structures will be based on corresponding damage models as well as on cohesive models including hydrogen diffusion.

Indentation testing on nano-sized magnesium column Indentation testing on nano-sized magnesium column

Fundamental experimental and modelling work is the key for understanding the deformation, damage and fracture mechanisms of novel light-weight materials. Our approach requires a tight connection of the modelling activities with experiments conducted over several length scales from the nano to the macro dimension. Innovative nano and micromechanical experiments developed and conducted in the new NanoLab will provide experimental information on the deformation and damage behaviour of material volumes with a characteristic length of a few nanometres up to several micrometers. It will be possible to study the effect of grain boundaries, precipitates and deformation twins, which will be directly relevant for the processing of light-weight alloys in Topic "Light-Weight Structural Materials".

Micro-mechanical Simulation Micro-mechanical Simulation

This research area delivers advanced material models for sophisticated simulation tools which are needed for the reliability assessment of light weight structures. A key point is the tight connection of the modelling activities with experiments on macroscopic and microscopic scale (see also Structural Integrity). The mechanical behaviour of relevant light weight materials is investigated and described in the context of components made by specific production processes considering the service conditions given by mechanical and thermal loads and chemical environment. Material models describing the deformation and damage behaviour of Al- and Mg-alloys are derived using hybrid numerical and experimental techniques with particular emphasis on micromechanical approaches.

Contact

Prof. Dr.-Ing. Jörn Mosler

Phone: +49 (0)4152 87-2679

Fax: +49 (0)4152 87-2595

e-mail contact