Experimental–numerical assessment of ductile failure of Additive Manufacturing selective laser melting reticular structures made of Al A357

In the present paper, an investigation on the ductile behavior of trabecular additive structure is presented. To characterize the material and assess its ductile response, dedicated experimental tests were performed, namely, specimens with different geometries were designed to induce a wide range of triaxiality values into the material and were printed using the selective laser melting technology in Al A357. The material model is based on both classical incremental model of plastic response with isotropic hardening and phenomenological concept of damage. All the experimental tests on additively manufactured specimens were numerically reproduced in order to retrieve the actual stress state, quantify the plastic strain at failure, and calibrate a ductile damage model. Then, some samples of the trabecular structures, with two different trusses diameters, were also tested under compressive loads and the global behavior of the structure analyzed. All the tests were also simulated using Finite Element Analysis (FEA) to prove the effectiveness of the damage model. Finally, an exhaustive discussion on the comparison between experimental and numerical results was provided.