AbstractIn this paper, the effect of ductile damage on the behavior of a dented Aluminum pipe subjected to internal pressure is investigated. The plastic behavior of pipes under indentation is studied using continuum damage mechanics theory and the elastic-plastic finite element analysis. Finite element calculations are carried out using the damage plasticity model proposed by Xue and Wierzbicki. The proposed damage plasticity model incorporates effects of both hydrostatic stress and the Lode angle to define the fracture envelope. Numerical calculations for different ranges of internal pressures and indenter diameters with and without damage effect are carried out and results are compared. It is shown that damage has a significant effect on the load bearing capacity of an indented pipe. Results of the present study confirm the credibility of the proposed model in predicting the ductile fracture under multi-axial state of stress loadings.