Role and effect of mechanical polishing on the enhancement of the duplex mechanical attrition/plasma nitriding treatment of AISI 316L steel

Therefore, the aim of this investigation is to characterize and to discuss the effect of SMAT on the nitrogen diffusion into an austenitic stainless steel AISI 316 subjected to the duplex surface treatment. A second objective is to study the effects of the intermediate polishing step on the friction coefficient and hardness. In order to better understand the link between the generated microstructures and the diffusion kinetics and tribological responses, samples have been characterised by many different techniques such as Optical and Scanning Electron Microscopy (OM and SEM), X-Ray diffraction, hardness and ball-on-disc tests. Special attention was paid to the formation of oxide layers. The superficial and in-depth chemical composition of the SMATed samples were characterised by Energy Dispersive X-ray spectrometry (EDS) and Glow Discharge Spectrometry Profiles (GDOES), respectively.