Numerical modeling of the tensile deformation process of sintered 316L based on microtomography of porous mesostructures

This paper concerns the numerical modeling of the tensile deformation process of porous sinters prepared from 316L powder. In the research specimens with 41%, 33% and 26% porosity were used. To take into account the porosity of materials (at a mesoscale) in the numerical modeling, X-ray microtomography was used. Based on the micro-CT images three-dimensional models were generated which mapped porous structures of the materials. Then, the surfaces of the models were subjected to triangulation and saved as finite element meshes. Numerical calculations were performed using the finite element method (FEM). To define the material nonlinearity the true stress-strain curve of solid 316L was used. Two approaches were employed for modeling the deformation process. The essence of the applied methods was the reduction of the impact of the non-mapped geometries (of a size less than the micro-CT accuracy) on mechanical properties of the materials. As a result of the calculations carried out by two methods, stress and strain fields were obtained and nominal stress-strain curves of the porous materials were determined. Based on the results of numerical calculations the influence of material discontinuities at the mesoscopic scale on macromechanical properties was investigated. (C) 2015 Elsevier Ltd. All rights reserved.