Comparison of Ductile Fracture Models on Load Bearing Capacity of a Dented Aluminum Pipe Subjected to Internal Pressure

In this work, three ductile fracture models based on different mechanical models namely Wilkins et al. (W), improved Johnson-Cook (J-C) and Xue and Wierzbicki (X-W) are introduced in the elastic-plastic finite element analysis to obtain the load bearing capacity of a dented aluminum pipe subjected to internal pressure loading. The target dent depth is considered as an indication of the load bearing capacity of the aluminum pipe with internal pressure under indentation process. Different combination of parameters that play important role in predicting the fracture initiation is considered by each of the proposed ductile fracture models. Numerical calculations for different values of internal pressures and indenter diameters with and without damage effects are carried out, and results of the proposed ductile fracture models are compared. The value of the target dent depth of the (W) model is found to be much higher and that of the improved (J-C) model is a little less than that of the (X-W) model. According to the experimental results that were reported on the fracture initiation and results of this research, it may be concluded that (X-W) model is more reliable and applicable in comparison with other models. It is also shown that the damage has a significant effect on the load bearing capacity of an indented pipe.