Additive manufacturing of multiple layered materials (Ti6Al4V/316L) and improving their tribological properties with glow discharge surface modification

Selective Laser Melting (SLM), which is a kind of laser powder bed fusion additive manufacturing technology, is commonly used in the manufacturing of AISI 316L stainless steel components. This study aims to enhance the mechanical and tribological properties of 316L manufactured by using SLM and plasma oxidation treatment in a glow discharge atmosphere. For that reason, Ti6Al4V layers were formed on 316L stainless steel samples by selective laser melting. Samples with a duplex structure (316L substrate and Ti6Al4V layer) were oxidized at 650 °C and 750 °C for 1 h and 4 h in the plasma atmosphere. The characterization of the formed Ti6Al4V and oxide layers is determined by the Vickers micro-hardness tester, scanning electric microscope, 3D profilometer, Energy dispersive X-ray spectrometer, and X-ray diffractometer. Wear tests were performed against Al2O3 balls under a load of 10 N, dry sliding ambient air conditions by a pin-on-disk tribometer. It was observed that the hardness and wear resistance of Ti6Al4V layered and plasma-oxidized samples were better than the uncoated 316L samples due to the formation of titanium oxide phases and diffusion zone depth. The best wear resistance is obtained in the sample with the highest hardness value. •Layered samples (Ti6Al4V/316L) were produced by Selective Laser Melting (SLM).•Plasma oxidizing process was applied to the samples at various temperatures and times.•After the process, TiO2 layer and diffusion zone were increased surface hardness.•Combined effects of SLM and plasma oxidizing improved the wear resistance of 316L.