A Modified McClintock Criterion Considering the Third Stress Invariant 2011-28-0084

This paper presents a study on prediction of ductile failure in metals using the combination of a void growth model and a constitutive law for the void containing solid. The void growth model is a modification of the well established McClintock criterion whereas the constitutive law is the modified Gurson's model. An advantage of the proposed criterion is the capability of predicting not only the onset failure but also the propagation direction by evaluating the rate of void growth in different principal stress directions. Moreover, by introducing a Lode angle dependent parameter to define the loading asymmetry condition, the shear effect is also taken into account. The proposed criterion was implemented using user-subroutines in ABAQUS. The model was calibrated and correlated by the uniaxial tension, shear and notched specimen tests. Numerical results were validated by comparing with the test data.