Forschungszentrum Jülich GmbH (JÜLICH) is one of the leading research institutions in Germany with
nearly 7,000 employees, belonging to the Helmholtz Association (HGF), Germany’s largest research organization. Energy technology is one of the main research topics with an involvement of approx. 450 person-years.
The SOC cross-cutting group at JÜLICH is one of the world’s largest and has produced several world record achievements in the past years, including an SOFC short stack that reached more than 100,000 h operating time with a low degradation rate. Over the past 25 years JÜLICH has been involved in several national programs as well as in several European projects co-operating with research institutes (ECN, Risø National Laboratory / DTU, VTT, CEA, KIT etc.) and industries (Haldor Topsoe, H. C. Starck, Wärtsilä, Sulzer / Hexis, Rolls Royce Fuel Cell Systems, Convion, AVL, Bosch, BMW, ElringKlinger etc.).
The IEK The IEK (German abbreviation for Institute of Energy and Climate Research) consists of fifteen
individual sub-institutes covering either single applications like photovoltaics or troposphere, or crosscutting issues within e.g. the IEK-1 (Materials Synthesis and Processing) or IEK-2 (Microstructure and
Properties). The latter two are part of the NOUVEAU project. Additionally, two so-called Helmholtz-
Institutes, located at a German university (U Münster and FAU Erlangen-Nürnberg), but organizationally integrated into the Forschungszentrum, complete the R&D portfolio.
IEK-1 & IEK-2 The role of IEK-1 within the NOUVEAU project lies in the development and manufacturing of alternative steels for interconnects, combined with a suitable coating material and its coating technology.
Therefore, in the first step conventional stainless steels with a reduced Cr-content will be determined
and coated with the state-of-the-art coating material (MCF) as well as suitable alternatives. Different
coating techniques (as WPS, APS and AD) are intended to be investigated. In the next step, as a new
approach, the manufacturing of interconnects by powder metallurgical processes (e.g. MIM and
pressing) is striven, followed by the deposition of suitable coatings via screen printing as well as the
development of potentially necessary thermal treatments. The evaluation of the resulting samples is
focusing on the occurrence of cracking and the achievable densities, primarily via SEM and XRD.
Within the NOUVEAU project, IEK-2 is responsible for the evaluation and modelling of degradation of
the coated interconnect steel components. For this purpose, oxidation in controlled atmospheres
simulating various SOC operating conditions and at different temperatures are performed. The tests
include short time thermogravimetry and long-time cyclic oxidation exposures. Extensive
characterization of the oxidized material is performed using a range of analytical techniques including
XRD, GDOES, SEM/EDX/EBSD and, if necessary, TEM. Based on the testing and analytical results the
lifetime of coated components limited by oxidation (primarily by Cr-depletion in the steels) and coating
degradation will be modelled.