An Extended Ductile Fracture Prediction Model Considering Strain Rate Effects

This paper presents a rate-dependent extension of Jia-Zang ductile fracture model with five parameters considering void nucleation, growth and coalescence. A series of ductile fracture tests is designed and conducted on aluminum alloy (6016-T6) specimens, which allows wide ranges for stress state and strain rate (0.1–100/s) under room temperature. A hybrid experiment-simulation method is employed to investigate the effects of stress state and strain rate on the material ductility. The results indicate an increasing equivalent plastic strain to fracture for each specimen as the strain rate increases from 0.1/s to 100/s. In addition, several nonlinear empirical functions are used to extend the original model parameters with strain rate dependent integrated. Subsequently, an uncoupled ductile fracture model considering strain rate dependent is developed, which can work from quasi-static to dynamic scenarios.