Enfoque según la mecánica de fractura del micro-daño asistido por hidrógeno en alambres de acero perlítico de alta resistencia laminado en calienterecordando la textura de la escultura en piedra de michelangelo (TEPM)

Abstract

A fracture mechanics approach to hydrogen-assisted microdamage and failure analysis of high-strength pearlitic steel wires is presented. Fractographic analysis revealed micromechanical effects of hydrogen in the form of tearing topography surface (TTS). The progress of this microdamage is modelled as a macroscopic crack that extends the original fatigue precrack and involves linear elastic fracture mechanics (LEFM) principles. In this case, the transition from hydrogen-assisted microdamage (HAMD) in the form of TTS (subcritical mode) to cleavage-like topography (critical regime associated with catastrophic failure) takes place when a critical stress intensity factor (KH) is reached, and this value depends on the amount of hydrogen which penetrated the vicinity of the actual crack tip (the fatigue precrack plus the TTS extension). It is seen that the crack growth by TTS corresponds to the horizontal part (plateau) in the crack growth kinetics (CGK) curve da/dt-K until reaching the critical level KH.