PSI - Issue 28

Mohamed Ali Bouaziz et al. / Procedia Structural Integrity 28 (2020) 393–402 Author name / Structural Integrity Procedia 00 (2019) 000–000

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Fig. 7. J-R curves given by both methods.

Fig. 8. J-R curves given by both methods with the crack tip position found by the FE-based method enhanced with parabolic fit of the identification error.

6. Conclusion In this paper, the fracture properties of an additively manufactured polymeric material were investigated by two different methods based on DIC measurements. The kinematic fields obtained experimentally were used to evaluate the J -integral in the first approach. In the second one, an FE model was used to compute the displacement field over the considered region of interest. DIC results were utilized as boundary conditions. The J -integral was obtained with the built-in interaction integral of the FE code. The crack tip position was found by minimizing the error between computed and measured displacement fields of the inner nodes. Both methods were applied to a micro Single Edge Notched Tensile sample manufactured by fused filament fabrication (FFF) of acrylonitrile butadiene styrene (ABS). The FE-based method showed very high robustness to accurately locate the crack tip. The crack length was quantified in an automatic way that did not require any visual inspection. An improvement was proposed in this study by introducing a parabolic interpolation in the procedure of