Triaxiality alone is not sufficient to account for the role of stress
state on ductility in materials that exhibit shear effects on fracture
strain. For these materials, it has been proposed that ductility also
depends on the third invariant of the stress deviator. Recently, Bonora
and Testa [N. Bonora, G. Testa, Plasticity damage self-consistent
model incorporating stress triaxiality and shear-controlled fracture
mechanisms – model formulation, Eng. Frac. Mech. 271, 108634 (2022).]
derived a plasticity damage self-consistent (PDSC) model considering
damage contributions due to intervoid necking, shearing, and sheeting
for an arbitrary stress state. In this work, the PDSC model has been
applied to Al2024-T351 considering the experimental results reported in
the literature obtained on several different sample geometries and
material batches. The ability of the model to predict the transition
from cup-cone to slant fracture for different stress states is shown. In
addition, the possibility to predict ductile fracture in the negative
stress triaxiality range has been also demonstrated showing that it can
occur for stress triaxiality even much less than -0.5 as long as there
is a dominant shear deformation state.