Hybrid search methodology for mechanical characterization of material produced via WAAM assuming Gurson porous material

In this work, the use of Gurson's porous material is proposed for the mechanical characterization of specimens produced via additive manufacturing. First, a plate from ER70S-6 wire was produced via Wire and Arc Additive Manufacturing (WAAM)—Cold Metal Transfer (CMT) for the deposition process. Subsequently, specimens were manufactured from different directions of a plate with 4 mm of thickness to assess the level of anisotropy and porosity. The experimental tensile tests were carried out until fracture under strain control. Through a hybrid search method based on genetic algorithm and gradient, the material parameters were characterized, such as the isotropic hardening curve and initial and critical porosity. Finally, a correlation between the scanning and building directions, and the mechanical properties were done, using the model based on Gurson as reference. It was observed that the constitutive model is adequate to represent the behavior of materials produced via additive manufacturing, showing that the matrix of the material, in this case, has about 5–15% of initial porosity, assuming different directions for building and scanning directions.