Sensitivity of Stainless Steel Fracture to Triaxiality Factor and Lode Parameter Using Dislocation Density Approach

Abstract

This work is devoted to the analysis of the influence of the triaxiality factor and the Lode parameter on the ductile fracture of a stainless steel tube. A micromechanical-based model incorporating several deformation mechanisms and formulated in the framework of the dislocation density theory is chosen to model the viscoplastic behavior of the 316L stainless steel. After adaptation of the implementation of the model into the finite element code Abaqus 2020 and the calibration of the model parameters with experimental available results, simulations of healthy and notched tubular specimens were carried out. In order to vary the triaxiality and Lode angle, we used specimens of different sizes and notch shapes. The results showed the capacity of the model to reproduce the experimental results of tubular structures. It was found that the strength and ductility of the specimens depend on the Triaxiality Factor and Lode Parameter.