Abstract
A concave R-curve for an AlMgZn alloy covers the transition from fully flat to fully slant fracture in 25 mm thick specimens of varying geometry. The transition is associated with the onset of plane stress conditions near the crack front. The concave R-curve is analysed using the increasing width of the shear lips, as in the Krafft et al. model, which increased the plastic work parabolically. The elastic and plastic work rates are evaluated using parabolic curve fits to the R-curve data. The present study showed that the plastic work rate scales with the crack extension from fully flat to fully slant fracture, which is geometry dependent
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Cheung, S., Luxmoore, A. A shear lip analysis of concave R-curves for an AlMgZn alloy. International Journal of Fracture 117, 195–205 (2002). https://doi.org/10.1023/A:1022050618899
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DOI: https://doi.org/10.1023/A:1022050618899