PSI - Issue 68

I. Yucel et al. / Procedia Structural Integrity 68 (2025) 1287–1293 / Procedia Structural Integrity 00 (2024) 000–000 Yucel et al.

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Fig. 3. Force vs. displacement curves for PST specimen

Fig. 4. Crack path predictions for PST specimen for MMC (left) and PF (right) models & element sizes (0.5 mm and 0.1 mm)

specimen. The MMC model simulations give relatively consistent results with the experiment; however, the model still shows mesh dependency.

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Fig. 5. Force vs. displacement curves for ISS specimen

For the PF simulations, the force-displacement and crack path results are presented in Fig. 7. Results converge for element sizes 0.1 and 0.05 mm. In addition, the crack pattern is almost identical in each case. Again, due to early material degradation, the model predicts a smaller force compared to uncoupled models. This issue can be solved by changing the degradation function. The influence of PF model parameters on the model’s response is demonstrated through a set of simulations per formed on the ISS specimen with a sweep mesh configuration of 0.1 mm. The e ff ects of these parameters on the force-displacement curve are depicted in Fig. 8. Fracture toughness alters the hardening curve but does not cause a significant change at the point of a sudden drop in loading capacity. Conversely, while plastic capacity does not a ff ect the hardening curve, it significantly influences the fracture point. This is because plastic capacity acts as a threshold