Biaxial experiments on characterization of stress-state-dependent damage in ductile metals

  • Michael BrünigEmail author
  • Moritz Zistl
  • Steffen Gerke
Production Process


The paper discusses new biaxial experiments to characterize stress-state-dependent damage and fracture processes in ductile metals on different scales. To motivate the experimental program a phenomenological continuum damage model is presented demonstrating the need of experiments covering a wide range of stress states and loading histories. Biaxial experiments with the X0-specimen taken from thin metal sheets tested under different load ratios are discussed with focus on proportional and corresponding non-proportional loading paths. During the tests strain fields on the surfaces of critical regions of the specimen are monitored by digital image correlation technique elucidating formation of localized strain bands leading to damage and failure. After the experiments fracture surfaces are examined by scanning electron microscopy revealing different damage and fracture process on the micro-scale depending on the stress states and the loading histories.


Ductile metals Damage Stress state dependence Biaxial experiments Digital image correlation Scanning electron microscopy 



The project has been funded by the Deutsche Forschungsgemeinshaft (DFG, German Research Foundation) – project number 322157331, this financial support is gratefully acknowledged. The SEM images of the fracture surfaces presented in this paper were performed at the Institut für Werkstoffe im Bauwesen, Bundeswehr University Munich and the support of Wolfgang Saur is gratefully acknowledged.


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Copyright information

© German Academic Society for Production Engineering (WGP) 2019

Authors and Affiliations

  1. 1.Institut für Mechanik und StatikUniversität der Bundeswehr MünchenNeubibergGermany

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