Abstract
Two independent experimental techniques are used to measure the strain distribution within the plastically deformed region around a crack tip. Moiré grid interference is used to measure the in-plane strain with the specimen grid engraved directly on the specimen surface. Optical interference is used to measure the through-the-thickness strain over the same engraved area. The testing arrangement allows measurement of at-load strain as well as residual strain. The measured strain distribution is compared with recent work by Swedlow using a finite-element numerical technique and with results of the etch-pit technique used by Hahn and Rosenfield.
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Underwood, J.H., Kendall, D.P. Measurement of microscopic plastic-strain distributions in the region of a crack tip. Experimental Mechanics 9, 296–304 (1969). https://doi.org/10.1007/BF02325135
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DOI: https://doi.org/10.1007/BF02325135