24th International Colloquium Tribology - January 2024 65 Tunable Viscosity of PAG and its Application in Sheet Metal Forming Dominic Linsler 1,2* , Korhan Celikbilek 1,2 , Stefan Reinicke 1,3 , Bernd Aha 4 1 Fraunhofer CPM, Freiburg, Germany 2 Fraunhofer IWM MikrotribologieCentrum µTC, Freiburg, Germany 3 Fraunhofer IAP, Potsdam, Germany 4 Zeller+Gmelin GmbH & Co KG * Corresponding author: dominic.linsler@iwm.fraunhofer.de Abstract Sheet metal forming by deep drawing is one of the most important forming processes in industry, which is mainly used in large-scale production because of the low running costs. Due to higher demands on formed products and smaller batch sizes, controlled process management is becoming increasingly important. This controlled process management can be significantly improved by actively influencing the friction between the sheet metal and the tool, because the forming result depends on the material flow in several respects (folds, crack formation, springback). State-of-the-art is the local application of lubricant on the metal sheet before the forming process. Still, there are other ways of controlling friction between the metal sheet and the tool. Actively controlling the viscosity of the lubricant in the contact is a feasible approach that has already been demonstrated via UV-triggered anthracene dimerization in respectively functionalized lubricants [1]. The characterization of the tunability of the viscosity of different PAG and fatty acids is carried out in-situ in a rheometer. The effectiveness of the viscosity change on the drawing forces could be demonstrated in the Erichsen cupping test and strip drawing tests. With the results, the development of a higher technology readiness level for the application in sheet metal forming is promising. References [1] C. Gäbert et al.: ACS Appl. Polym. Mater. 2020, 2, 12, 5460-5468 doi: 10.1021/ acsapm.0c00794.