Dual-scale modeling of temperature-dependent deformation and damage in martensitic steels

Understanding the deformation and failure of martensitic steels under extreme service conditions is critical for ensuring the safety and reliability of industrial tooling and structural components. In this study, tensile tests were conducted on a low-carbon martensitic steel at 297 K, 193 K, and 133 K using specimens designed to induce different levels of stress triaxiality. A dual-scale modeling framework, integrating continuum mechanics with crystal plasticity (CP) simulations, was developed to investigate temperature-dependent deformation localization and failure. Macroscopic fracture properties of the material are captured using a damage mechanics approach, whilst the underlying microscopic deformation behavior was analyzed using CP modeling with a hierarchical representative volume element (RVE). Results reveal that improved local ductility at lower temperatures is stress state-dependent, with minimal temperature influence on texture evolution. Shear-dominated loading (low stress triaxiality) induces significant lattice reorientation, enhancing near rot-goss { 110 } ⟨ 332 ⟩ and near brass { 331 } ⟨ 136 ⟩ components, whereas uniaxial and notch tension (moderate/high triaxiality) lead to limited, uniform rotations. Grains with initial γ ‐ fiber orientations are prone to strain localization under shear loading. These findings provide a clearer understanding of the multiscale deformation and failure behavior of martensitic steels under complex loading and offer guidance for the design and application of these materials in engineering environments.