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Experimental and Computational Study of Ductile Fracture in Small Punch Tests.

ABSTRACT: A unified experimental-computational study on ductile fracture initiation and propagation during small punch testing is presented. Tests are carried out at room temperature with unnotched disks of different thicknesses where large-scale yielding prevails. In thinner specimens, the fracture occurs with severe necking under membrane tension, whereas for thicker ones a through thickness shearing mode prevails changing the crack orientation relative to the loading direction. Computational studies involve finite element simulations using a shear modified Gurson-Tvergaard-Needleman porous plasticity model with an integral-type nonlocal formulation. The predicted punch load-displacement curves and deformed profiles are in good agreement with the experimental results.

SUBMITTER: Gulcimen Cakan B

PROVIDER: S-EPMC5666991 | biostudies-literature |

REPOSITORIES: biostudies-literature

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