Abstract

Both elastic and elastic–plastic stress–strain response were studied for a series of part-circular and V-shaped notches in flat specimens. Both the peak strain at the notch root and the strain distribution along the notch bisector were studied. These quantities were determined analytically using detailed finite element analysis (FEA), and it was shown that significant differences can arise between detailed FEA results and two of the commonly used approximations for the peak notch strain response: Neuber’s rule and Glinka’s equivalent strain energy density theorem. These differences can become significant for notches with low acuity. The strain response for these configurations was also studied experimentally using two measurement techniques: optical fibers and surface differential displacement mapping. Agreement was shown between computed response strains and measured strains for some of the eight notch configurations and two aerospace alloys studied, while for others, experimental difficulties prevented agreement. These difficulties are described in detail.

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