Fracture Behavior of Headed Studs: Ductile Fracture of Cold Heading Steel ML15

In this paper, the fracture behavior of ML15 cold heading steel was investigated based on the ductile fracture theory. Smooth and notched bar, flat grooved and tensile–shear mixed flat plate specimens were designed, and tensile tests were carried out to examine the fracture mechanism of ML15. The micromechanical characteristics of the fracture surfaces of different specimens were studied by performing scanning electron microscopy. The results showed that the specimens under different stress states showed different micro fracture morphologies. The Rice–Tracey model and Bai–Wierzbicki model were calibrated using test results. Based on the calibrated fracture locus, a finite element model is developed and compared to the test results, which confirms the feasibility of the calibrated fracture locus for metal failure analysis.