Akademik Veri Yönetim Sistemi
International Journal of Plasticity, cilt.203, 2026 (SCI-Expanded, Scopus)
The microstructure of dual-phase (DP) steels induces complex crack initiation and propagation mechanisms that are crucial to understand for enhancing formability and alloy performance. In this work, a phase-field fracture (PFF) model for ductile materials is employed to investigate crack initiation and propagation in DP microstructures. Several representative volume elements (RVEs) are constructed from both real microstructural images of DP600 steel and artificially generated microstructures to assess the influence of martensite morphology on failure behavior. Finite element simulations are carried out under uniaxial, equibiaxial, and plane strain tension loading conditions. The framework successfully reproduces experimentally observed trends in damage initiation, capturing both the localization strain values and the specific sites of crack initiation within the microstructure. In particular, thin, bridge-like martensite regions connecting larger martensite islands, and aligned with the loading direction, are identified as critical zones for early damage initiation under uniaxial tension. Among the loading conditions, plane strain tension is found to be the most critical, exhibiting the earliest localization with minimal sensitivity to microstructural variation. Overall, the proposed framework demonstrates strong agreement with experimental observations, validating its effectiveness for predicting damage mechanisms in DP steels.