Ductile fracture simulation of hydropiercing process based on various criteria in 3D modeling

Hydropiercing has been used widely in the past decade in the automotive industry. So far, the ductile fracture of hydropiercing process considering the effect of hydroforming has not been studied in detail due to the complicated deformation process. In order to simulate hydropiercing process accurately, a 3D model considering the effect of hydroforming process has been developed in this study. Six ductile criteria were implemented to predict crack initiation and propagation by means of the user subroutine VUMAT of ABAQUS. The comparative study among the results obtained by the simulations using the different ductile criteria and the experiments was explored. The model using the Rice and Tracey Criterion shows good agreement with the experiment at loading pressure of 60–60 MPa, however the others could not. Moreover, the simulation errors using the Rice and Tracey Criterion at different loading pressure and hydropiercing type are small enough too compared with experiments so that this criterion could be used to simulate the hydropiercing process. Finally, the deformation mechanism of hydropiercing process has been discussed on the bases of simulations with the Rice and Tracey Criterion and experiments.