FOR 1509:  Ferroic Functional Materials - Multiscale Modelling and Experimental Characterisation

• Subject Area: Mechanical and Industrial Engineering ; Construction Engineering and Architecture ; Materials Science and Engineering
• Term: from 2012 to 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 167466072

The Research Unit focusses on the continuum-mechanical modelling and experimental characterisation of ferroic functional materials. Of particular interest are materials, which allow for coupling between different physical quantities as for instance coupling between electrical and mechanical, mechanical and magnetic or magnetic and electrical fields. The main focus is thus on ferroelectrics and ferromagnetics as well as on multiferroic composites. The properties of functional materials emerge on different scales. Some exist on the atomic scale as, for example, the magnetisation. Others, as e.g. the electric polarisation, are present on the unit cell level of a crystal. Furthermore, some materials obtain their functional properties only when the above quantities couple over a larger length scale as for instance in case of multiferroic composites. In order to describe those materials, the Research Unit is active on multiple scales. The activity spans molecular statics, modelling of microstructure evolution, and the phenomenological description by using suitable homogenisation techniques. In this context, the modelling on the smaller scales serves as physical basis and motivation for modelling on the scale next in size. Independent on the considered scale, the numerical stability and robustness of the used algorithms play a key role. Thus, the goal of the Research Unit is to develop a new quality in reliable and robust modelling tools for the description of the complex, non-linear, magneto-electro-mechanical interactions on multiple scales. This will be achieved through collaboration in several fields of research. One major building block is the modelling of microstructure evolution on different scales by using atomistic methods, phase-field methods, and relaxation-based methods as well as classical continuum approaches. In addition to that, the determination of the effective response of the functional materials is of particular interest. This will be obtained by developing suitable homogenisation techniques that allow for a transition between neighbouring scales. Of course, all models have to be validated and needed material parameters have to be identified. This will be realised by measuring a representative experimental data-base of the magneto-electro-mechanical material response.

• DFG Programme: Research Units

Projects

• Coordination Funds (Applicant Schröder, Jörg )
• Design and analysis of functional composites with strain induced magneto-electric coupling (Applicants Brands, Dominik ;  Schröder, Jörg )
• Experimental characterization of magneto-electric composites (Applicants Lupascu, Doru Constantin ;  Wende, Heiko )
• Investigation of size effects in ferroic materials using phase field simulations (Applicants Müller, Ralf ;  Xu, Bai-Xiang )
• Microstructural interaction and switching in ferroelectrics (Applicants Menzel, Andreas ;  Svendsen, Robert )
• Modeling and Homogenization of Magneto-Mechanical Material Behaviour at Multiple Scales (Applicant Keip, Marc-André )
• Molecular static methods for the simulation of ferroelectric materials (Applicant Steinmann, Paul )
• Numerical Relaxation for the Description of Microstructure Evolution in Functional Magnetic Materials (Applicants Bartel, Thorsten ;  Kiefer, Ph.D., Björn )

• Spokesperson: Professor Dr.-Ing. Jörg Schröder