MULTIMAT - Multiscale modeling and characterization of phase transformation in advanced materials
Many applications of so-called smart materials are based on changes in their
atomic, nano- and microstructure brought about by phase transformations. In
order to further develop and apply these materials we need a better and
fundamental understanding of the underlying principles of these
processes. MULTIMAT aims to continue existing and fruitful collaborations
between strong theoretical and experimental research groups active in this
exciting and promising field of advanced materials.
MULTIMAT is a Marie Curie Research Training Network (RTN) funded by the European
Union. Many teams mainly from Europe contribute to the MULTIMAT network, see
the team list on the homepage of the MULTIMAT network
. The team from the
University of Bonn consists of
Within our research group, Prof. Dr. Michael Griebel
and Dr. Marcel Arndt
are involved in the following projects of the MULTIMAT network:
The macroscopic behavior of material is governed by effects on the atomic level
and even finer length scales. Therefore a precise description of the material
behavior needs to be targeted on the full hierarchy of scales.
To this end, it is essential to study the relationship of the different length
scales. It is necessary to develop both analytical and numerical techniques to
bridge the different length scales. Several aspects of this topic are addressed
by our two projects within the MULTIMAT network. As an application, we study
the behavior of shape memory alloys, which exhibit an interesting multiscale
Project "Multiscale numerical algorithms: Coupling of different physical
models on the micro scale and the macro scale"
The goal of this project is to develop numerical techniques in which models from
different length scales are coupled numerically, that means to deal with
different models on different scales simultaneously within a single simulation.
Instead of using a single model on a single length scale, different models on
different length scales are integrated in one simulation.
The underlying principle is to use the macro model whereever it is applicable,
and to fall back to the more precise but computationally costly micro model in
regions where the macro model fails or where its accuracy is insufficient. This
way, numerical simulations can be efficiently performed which are too costly on
the microscale and which involve effects which cannot be described on the
Project "Computational modeling of multiscale materials: Derivation of
continuum mechanical models from atomistic models"
In this project, analytical and computational techniques are developed to derive
models on larger length scales from models on finer length scales. The rigorous
derivation allows for models which are more accurate than conventional
phenomenological models. Especially we focus on deriving high-accuracy
continuum mechanical models from atomistic models.
Additionally, we compare the achieved results with experimental data to verify
the newly developed analytical and numerical techniques.