PSI - Issue 68

Eren Çelikses et al. / Procedia Structural Integrity 68 (2025) 1045–1050

1049

E. C¸ elikses et al. / Procedia Structural Integrity 00 (2024) 000–000

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Fig. 3: Distributions of maximum principal stress for the DP800 (a) banded and (b) dispersed microstructures loaded in y and x directions.

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Fig. 4: Stress vs. strain curves of (a) banded and (b) dispersed microstructures deformed in x and y directions.

4. Conclusion

The performance and formability of DP800 dual-phase steels with banded and dispersed martensite microstructures are analyzed through experiments and numerical simulations. The banded microstructure exhibited lower performance in hole expansion tests and forming limit curves, while both steel samples showed similar behavior in standard uni axial tensile tests. Numerical analysis further revealed that the banded martensite microstructure responds di ff erently when subjected to tension parallel versus perpendicular to the band direction. Additionally, regions of high-stress concentration are observed around the martensite bands, which may initiate early cracking in martensite, potentially leading to premature failure.

Acknowledgements

We would like to thank Emre Dombaylı and Refiye Ardalı for their invaluable support in sample collection, prepa ration, and testing. We also extend our gratitude to Yasin Akbas¸, the developer of the mesh generation software from microstructure images (BorPha). Additionally, we would like to thank Can Erdogan and Berkehan Tatlı for their support in conducting the numerical simulations.

References

Acar, S.S., Bulut, O., Yalc¸inkaya, T., 2022. Crystal plasticity modeling of additively manufactured metallic microstructures. Procedia Structural Integrity 35, 219–227.