EUROPEAN CONGRESS AND EXHIBITION ON ADVANCED MATERIALS AND PROCESSES - EUROMAT 2021

Additive manufacturing technologies (AM) have been identified as one of the most promising production technologies of the last decade. They can carry out the transition from mass production to mass customization in the main industrial sectors, as well as is considered that they can exponentially accelerate the transformation from manufacturing to 4.0 industry. There are some AM technologies applicable to metals such as Direct Laser Deposition (DLD) and the Selective Laser Melting (SLM). The main objective of this research is to study the influence of the 316L microstructure in the final properties of 3D manufactured samples by DLD with diode laser, SLM with laser of fiber and SLM with CO2 laser with different scan speeds and build orientations.
Evaluation of the effect of AM technologies on the microstructure, corrosion and mechanical properties of the samples has been carried out.
SEM examinations revealed austenite in SLM and DLD samples with delta ferrite as interdendritic phase (bigger in the DLD pieces). The manufacturing conditions and methods used have great effect on the porosity, roughness and mechanical properties of the samples.
Bending, wear and hardness tests show that Young Modulus of the samples manufactured by SLM with laser fiber is greater than those manufactured by DLD, as in the case of hardness. The presence of defects in the SLM parts with CO2 laser reduces the strength and ductility of the material, compared to those manufactured with the other methods used, while the manufactured specimens using SLM with fiber laser have greater strength and ductility than the others. Fracture surface of each specimen was observed.
Corrosion tests show that the pieces manufactured by CO2 laser are the most prone to corrode than those manufactured by DLD which are also sensitive to corrosion than the samples obtained by SLM with fiber laser.