Evaluation of Near-Threshold Fatigue Crack Propagation under Mixed Mode II+III in ARMCO Iron

Evaluation of Near-Threshold Fatigue Crack Propagation under Mixed Mode II+III in ARMCO Iron

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The research was focused on the near-threshold fatigue crack propagation under mixed mode II+III in the ARMCO iron. The aim was to evaluate selected mixed-mode criteria to find a suitable description of the mixed-mode crack propagation. The data were taken from experiments on cylindrical specimens with circumferential crack made of the ARMCO iron and loaded by various combinations of modes II and III. The dependences of stress intensity factors (SIFs) in mode II and III on the polar angle as well as on the crack length were numerically calculated using FEM. For sorting out the mixed-mode data, three different formulae were used (each normalized to 1 when approaching the mixed-mode threshold).

The research was focused on the near-threshold fatigue crack propagation under mixed mode II+III in the ARMCO iron. The aim was to evaluate selected mixed-mode criteria to find a suitable description of the mixed-mode crack propagation. The data were taken from experiments on cylindrical specimens with circumferential crack made of the ARMCO iron and loaded by various combinations of modes II and III. The dependences of stress intensity factors (SIFs) in mode II and III on the polar angle as well as on the crack length were numerically calculated using FEM. For sorting out the mixed-mode data, three different formulae were used (each normalized to 1 when approaching the mixed-mode threshold).

The research was focused on the near-threshold fatigue crack propagation under mixed mode II+III in the ARMCO iron. The aim was to evaluate selected mixed-mode criteria to find a suitable description of the mixed-mode crack propagation. The data were taken from experiments on cylindrical specimens with circumferential crack made of the ARMCO iron and loaded by various combinations of modes II and III. The dependences of stress intensity factors (SIFs) in mode II and III on the polar angle as well as on the crack length were numerically calculated using FEM. For sorting out the mixed-mode data, three different formulae were used (each normalized to 1 when approaching the mixed-mode threshold).

mode II+III, crack growth threshold, mixed-mode criteria, ARMCO iron

mode II+III, crack growth threshold, mixed-mode criteria, ARMCO iron

24.09.2012

Institute of Physics of Materials

Brno

978-80-87434-05-5

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