| Summary: | Fully pearlitic eutectoid steels have an excellent compromise of mechanical
strength and ductility and are widely used for rails, prestressing tendons and high-
strength wires. These excellent mechanical properties are a consequence of their
particular nanocomposite structure combining thin cementite lamellae (~12% volume
fraction) with ferritic lamellae. This complex substructure entails a complex
microstructural and property evolution with applied strain that is difficult to model.
In this work, a microstructure-based constitutive model for pearlite accounting
for both the elastoplastic behaviour and the damage evolution is presented. The
original formulation, valid for mesoscopic scales, considers the behaviour of ferrite
and cementite separately, assuming that strengthening occurs through the
mechanisms acting in ferrite. For its application in macro-scale systems such as wire
drawing, a multi-colony homogenization strategy has been applied. For damage, a
Continuum Damage Mechanics approach adapted to the features of pearlite has been
adopted with the coupling of damage to the mechanical response. The model has
been implemented for use in finite element simulations and has been calibrated using
experimental data of tensile and torsion tests. Subsequently, the model has been
validated, confirming its predictive capabilities across various aspects, including the
mechanical response under different stress states, the build-up of internal stresses and
the evolution of the microstructure with deformation.
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