Influence of 3d-printing parameters on the mechanical properties of 17-4PH stainless steel produced through Selective Laser Melting

Abstract

Additive Manufacturing (AM) is a technological process in which elements are fruitfully built up adding materials layer by layer. AM had a massive development in recent times, thanks to its intrinsic advantages, especially if compared with conventional processes (i.e. subtractive manufacturing methods), in terms of free-form design, high customization of products, a significant reduction in raw materials consumption, low request of postprocessing and heat treatments, use of pure materials and reduced time for final products to be marketed. In order to give an innovative contribution to the knowledge in the field of metal AM materials, this paper reports the main outcomes of an experimental campaign focused on the influence of several specific printing parameters on the mechanical features of the 17-4PH stainless steel, which is one of the most used metal for the Selective Laser Melting (SLM) technology. The influence of different printing directions and sample inclinations on the material mechanical behavior is assessed, with the aim of considering an innovative use in the field of structural engineering. Moreover, the effects due to scanning and recoating times are studied. In addition, the consequences of heat treatment (annealing) on both the residual stresses and the amount of residual austenite are appraised.

3D-printed metals: Process parameters effects on mechanical properties of 17-4 P H stainless steel

“…As already shown in a previous study [ 79 ], the mechanical behaviour, after heat treatment, appears to be not consistent with the result that are reported in literature, which usually provides, for annealed steel alloys produced by traditional methods, an increase in ductility and a reduction in strength [ 58 , 77 ]. Nevertheless, besides the experimental data supplied by the company producer of the 3D printer and of the metal powders employed (SLM Solutions) [ 80 ], which are in line with the recorded results, there are also several scientific outcomes about steel and nickel-based alloys, manufactured via selective laser melting [ 68 , [81] , [82] , [83] , [84] ], that confirm and validate the obtained results.…”

Geometrical Accuracy Analysis of Ti-6Al-4V Trusses Manufactured by Electron Beam Melting Process

“…This resulted in part distortion that compromised the powder deposition and melting stages in the subsequent layers. A strong dependence of the residual stresses and the yield strength on the building orientation was also found in [43] and [44], respectively.…”

Mechanical Performance of 17‐4PH Stainless Steel Produced Via Selective Laser Melting

“…Table 2 shows the chemical composition of the feedstock [16], [17]. Table 3 provides a summary of the physical properties of the raw 17-4PH stainless steel powder, supplied by SLM Solutions, while Table 4 contains the nominal mechanical features of the printed metal for two different printing directions [16], [17].…”

“…Table 2 shows the chemical composition of the feedstock [16], [17]. Table 3 provides a summary of the physical properties of the raw 17-4PH stainless steel powder, supplied by SLM Solutions, while Table 4 contains the nominal mechanical features of the printed metal for two different printing directions [16], [17]. A total of 18 samples, was produced to perform tensile tests in order to evaluate how the manufacturing process and its parameters affect the mechanical properties [12].…”