Electronic Material Properties - und Geowissenschaften ...

Collaborative Research Center (SFB)
„Electric Fatigue in Functional Materials“
Phase II: Jan. 2007 – Dec. 2010
www.sfb595.tu-darmstadt.de
The center for collaborative studies (Sonderforschungsbereich) has been awarded by the
Deutsche Forschungsgemeinschaft in 2002 to TU Darmstadt and is centered in the
Department of Materials and Earth Sciences with important contributions from the
Department of Chemistry and the Departments of Civil Engineering, Mechanical
Engineering as well as the Mechanical Engineering Department of the University of
Karlsruhe. The center was renewed in 2006 and has recently started its second four-year
funding period.
It is comprised of a total of 19 projects and financial resources for four years of about 8
Mio. €. The center has an active guest program with guests visiting from 2 days to 3
months. For specific information, please contact either the secretary of the center, Mrs.
Gila Voelzke, or the director of the center, Prof. Jürgen Rödel.
Contact:
Office: SFB 595: Electrical Fatigue in Functional Materials,
Institute of Materials Science
Petersenstr. 23
64287 Darmstadt
Tel.: +49-6151-16-6362, 6315
Fax: +49-6151-16-6363, 6314
Building/Room: L201 / 55
E-mail: roedel@ceramics.tu-darmstadt.de
Voelzke@ceramics.tu-darmstadt.de
Electrical fatigue in functional materials encompasses a set of phenomena, which lead to
the degradation of materials with an increasing number of electrical cycles. Electrical
cycling leads to both reversible and irreversible currents and polarisations. Ionic and
electronic charge carriers interact with each other and with microstructural elements in the
bulk as well as at interfaces (grain boundaries and domain walls) and interphases
(electrode/electrolyte). This in turn causes local changes in the distribution of electric
currents and electric potentials. As a consequence local overloads and material
degradation ensues and leads to irreversible loss of material properties. This material
degradation can lead finally to mechanical damage as well as to dissociation reactions.
The basic phenomena of electrical fatigue are not yet understood on a microscopic level.
The goal of this center of excellence in the second phase is the understanding of the
mechanisms leading to electrical fatigue. An understanding of the experimental results is
supported by concurrent materials modelling which is geared to encompass different time
and length scales from the material to the component.
A key feature of the center is therefore the steady comparison between theory and
experiment. This is utilized to find the physico-chemical origins of electrical fatigue as well
as to develop strategies for new materials and improved material combinations. The
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