Prediction of ductile failure using a local strain-to-failure criterion
- 965 Downloads
In this article, we provide the details of the predictive simulations performed by the University of Texas team in response to the 2012 Sandia Fracture Challenge (Boyce et al. in The Sandia Fracture challenge: blind predictions of ductile tearing. Int J Fract. doi: 10.1007/10704-013-9904-6, 2013). The material constitutive model was calibrated using the tensile test data through an optimization scheme. A modified Johnson–Cook failure criterion was also partially calibrated using the material characterization data obtained from a tension test and a compact-tension fracture test. These models are then embedded in a highly refined finite element simulation to perform a blind prediction of the failure behavior of the Sandia Fracture Challenge geometry. These results are compared with experiments performed by Sandia National Laboratories and additional experiments that were performed at the University of Texas at Austin with full-field three-dimensional digital image correlation in order to explore the different failure modes. It is demonstrated that a well-calibrated model that captures the essential elastic–plastic constitutive behavior is necessary to confidently capture the elasto-plastic response of challenging structural geometries; it is also shown that a simple ductile failure model can be used to predict ductile failure correctly, when proper calibration of the material model is established.
KeywordsLocalization Plasticity Simulations
This work was performed during the course of an investigation into ductile failure under two related research programs funded by the Office of Naval Research: MURI Project N00014-06-1-0505-A00001 and FNC Project N00014-08-1-0189. This support is gratefully acknowledged.
Supplementary material 1 (avi 22455 KB). Results of the SFC_blind_prediction indicating the development of PEEQ initially in the ligament A-D, subsequently in the ligament A-C, leading to failure along A-C-E.
Supplementary material 2 (avi 17701 KB). Video showing the development of equivalent plastic strain as obtained from the 3D-DIC for specimen S-09; the failure followed the path A-C-E.
Supplementary material 3 (avi 14969 KB). Video showing the development of equivalent plastic strain as obtained from the 3D-DIC for specimen S-11; the failure followed the path A-D-C-E.
- Boyce BL, Kramer SLB, Fang HE et al (2013) The Sandia Fracture challenge: blind round robin predictions of ductile tearing. Int J Fract. doi: 10.1007/s10704-013-9904-6
- Johnson GR, Cook WH (1985) Fracture characteristics of three metals subjected to various strains, strain rates, temperatures and pressures. Eng Fract Mech 21:31–48Google Scholar
- Lesuer DR, Kay GJ, LeBlanc MM (2001) Modeling large strain, high-rate deformation in metals. UCRL-JC-134118, Lawrence Livermore National LaboratoryGoogle Scholar