Surface Evaluation of Post-processed SLM-based 3D-printed SS316L Stent

Surface roughness in a stent is essential because it directly affects its biocompatibility by altering the interactions and behavior of blood cells and tissue with it. Smooth surfaces reduce the risk of thrombosis and inflammation, promote endothelial cell growth, and improve tissue integration. In this context, the present study examines the surface evaluation of a post-processed SLM-printed SS316L powder stent. Four post-processed samples were studied: electropolished (E), heat-treated (HT), electropolished with heat-treated (HTE), and untreated. Electropolishing (WHTE). The process performance was evaluated concerning surface roughness parameters, which were measured using a non-contact measuring system (Alicona). Furthermore, the obtained results were correlated with characterization techniques such as Scanning Electron Microscopy (SEM) and Electron Backscatter Diffraction (EBSD). From the results, it was observed that electropolished with heat-treated exhibits a lower Average surface roughness (R _a ) of 0.484 µm, a root mean square of the profile (R _q ) of 0.484 µm, a total height of the roughness profile (R _t ) of 2.789 µm, and a ten-point mean average of (R _z ) 1.98 µm. The obtained results were correlated with surface metallurgy from the perspective of bioengineering suitability. The study demonstrates that the combined effect of electropolishing and heat treatment enhances stent surface quality for biomedical applications.