The forming limit curve (FLC) is used to model the onset of sheet metal instability during forming processes e.g. in the area of finite element analysis, and is usually determined by evaluation of strain distributions, derived with optical measurement systems during Nakajima tests. Current methods are time or location dependent and heuristically limit the evaluation area to a small fraction of the available information and additionally show weaknesses in the context of brittle materials without a pronounced necking phase. The aim of this project is the development of an objective and automatic classification method to assess the failure behaviour of sheet metals during forming processes. Consequently, one key aspect of the proposed methods is the definition of a probabilistic FLC to enable an accurate prediction of material behaviours with multiple failure likelihoods e.g. for risk aware process planing, while being time and location independent. |