Development of energy-based testing and evaluation methods to analyze the fracture behavior of polymer materials under creep loading in mixed mode

• Applicants: Dr.-Ing. Ralf Lach; Professor Dr.-Ing. Stephan Marzi
• Subject Area: Polymeric and Biogenic Materials and Derived Composites ; Mechanics
• Term: since 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 524081030

The research topic is the mechanical failure behavior during creep of brittle as well as ductile thermoplastics under single-mode and mixed-mode loading. To investigate the growth of creep cracks, new test stands are to be developed which, in particular, allow an experimental analysis of the growth of cracks under a mode III and a combined mode I+III load for the first time. To investigate crack growth in mixed mode I+II, suitable creep tests should also be developed, which are not subject to the existing limitations of established test setups.The planned experimental and theoretical investigations are aimed at a significant further development of the international state of the art in science and technology in the field of characterizing time-dependent failure processes in polymers. A deeper understanding of the slow crack propagation behavior in polymeric materials should be gained, which enables an improved assessment of the long-term integrity of polymeric structures, for example in the automotive industry or in civil engineering.

• DFG Programme: Research Grants