Norbert Willenbacher

Norbert Willenbacher is a German physicist. He is the professor of mechanical process engineering at the Karlsruhe Institute of Technology. Willenbacher is known for discovering the capillary suspension phenomenon. He is the former President of the German Rheological Society.

Career In 1990, Willenbacher studied physics at Johannes Gutenberg University Mainz and completed his dissertation at the Max Planck Institute for Polymer Research.

In 2005, he became Head of the Institute of Mechanical Process Engineering and Mechanics at Karlsruhe Institute of Technology. From 2012 to 2014, he was the Dean of the Faculty for Chemical and Process Engineering at KIT. Since 2017, Willenbacher also serves as Head of the Technology Transfer Unit "Rheology and Formulation of Complex Fluids" at KIT Campus Transfer GmbH.

From 2013 to 2014, Willenbacher served as chairman of the supervisory board (Aufsichtsrat) of juwi AG, a renewable-energy project developer based in Wörrstadt, before stepping down in favor of Norbert Müller

Research Willenbacher's research focuses on the rheology of complex fluids and the relationship between their microscopic structure and macroscopic flow behavior. His work includes applications in coatings, printing, food, ceramics, batteries, and additive manufacturing.

His research group developed micro-rheo-mapping (MRM), an imaging-based method for measuring local rheological properties and studying structural variations in gels.

Willenbacher worked on the capillary suspension phenomenon. In a three-phase system consisting of a bulk liquid, particles, and a small amount of a second immiscible liquid, capillary forces induced by the secondary fluid can create a particle network spanning the entire sample volume. This network alters the rheological properties, converting a fluid-like suspension into a gel-like paste with a tunable yield stress.

Awards and honors NEULAND Innovation Award, Karlsruhe Institute of Technology (KIT) Publication Award, Rheologica Acta (2017) Publication Award, Journal of Rheology (2024)

Selected publications

Front side metallization of silicon solar cells – A high-speed video imaging analysis of the screen printing process, K Abdel Aal and Norbert Willenbacher, doi.org/10.1016/j.solmat.2020.110721 Phase-Change-Enabled, Rapid, High-Resolution Direct Ink Writing of Soft Silicone, Y Wang and N Willenbacher, Advanced Materials 34 (15), 2109240 (2022); doi.org/10.1002/adma.202109240 Imaging of the microstructure of Carbopol dispersions and correlation with their macroelasticity: a micro-and macrorheological study, C Oelschlaeger, J Marten, F Péridont, and N Willenbacher, Journal of Rheology 66 (4), 749-760 (2022) doi.org/10.1122/8.0000452