Implementation and application of Dung’s model to analyze ductile fracture of metallic material

Abstract

In this paper, the Dung’s microscopic damage model which depicts void growth under plastic deformation is applied to predict ductile fractures in high strength steel API X65. The model is implemented as a vectorized userdefined material subroutine (VUMAT) in the ABAQUS/Explicit commercial finite element code. Notched and smooth round bars under uniaxial tension loading are simulated to show the effect of equivalent plastic strain versus the void volume fraction growth of the material at and after crack initiation. Predictions of the ductile behavior from void nucleation to final failure stage are compared with the built-in Gurson – Tvergaard – Needleman (GTN) model in ABAQUS. Also, comparison with experimental results from the literature is discussed.