Ductile Fracture Criterion Parameter Calibration and Analysis: X80 Pipe Steel

Abstract To investigate the ductile fracture mechanical properties of high strength pipeline steel under a series of stress states, the basic mechanical properties and fracture parameters of X80 pipeline steel were obtained from four types of tensile specimens with six different stress concentration factors and their symmetrical finite element models by an experimental-simulation hybrid method. The ductile fracture parameters of the fracture criterion were calibrated by selecting three specimen data, and the calibrated fracture criterion was imported into ABAQUS using the Vumat subroutine to perform tensile simulations and construct two-dimensional planar fracture trajectories of the materials, and the predictive effects of the ductile fracture criterion were analyzed. The study demonstrates that the fracture criteria can be calibrated using the experimental-simulation hybrid method for data extraction from specimens with varying stress concentrations; the DF2014 ductile fracture criterion characterizes fracture behavior accurately and flexibly under different stress states, which was more accurate for predicting ductile fracture of high strength pipe steel. This research can serve as a reference for evaluating the ductile fracture failure of high strength steel pipes using the ductile fracture criterion.