| Abstract: | Hybrid experimental-numerical and experimental analyses were used to explore possible dynamic ductile fracture parameters associated with rapid crack propagation in 7075-T6 and 2024-T3 aluminum alloy, single edge notched (SEN) specimens of 1.6 mm thickness. Dynamic Moiré interferometry was used to record the displacement field, which was used either to drive a dynamic elasto-plastic finite element (FE) model of the fracturing SEN specimen or by itself, to determine the crack-tip J-integral, the $T_varepsilon ^* $ -integral and the crack tip opening angle (CTOA). The near-field J vanished but the near-field $T_varepsilon ^* $ reached a constant value with crack propagation. The CTOA associated with a low crack velocity also remained constant during crack propagation but fluctuated at higher crack velocity. The results of this preliminary study suggest that either the $T_varepsilon ^* $ or the CTOA criteria proposed for stable crack growth could be a suitable parameter for characterizing rapid crack propagation in these thin aluminum specimens. |
