Electropolishing of Coronary Stents

Abstract:

Produce of coronary stents demands advanced precision. In the present study, electropolishing was performed on stainless steel slotted tube coronary stents made by laser cutting. The surface quality of stents has a significant influence on biocompatibility, therefore the optimal method for electropolishing were explored. Additionally, acid pickling as the pretreatment of electropolishing was also conducted. Pickling was necessary prior to electropolishing for decreasing roughness of the cutting zone and for removing the oxide films covering the stent surface. An optimal condition for electropolishing could also be established and it caused a smooth stent surface. Material removal (weight loss and strut width change) in the process of both pickling and electropolishing was investigated. Furthermore, material characterization of the stents was determined by means of composition analysis, metallographic characterization and microstructural analysis.