The effect of electropolishing parameter on 316L stainless steel surface roughness for coronary stent application

The result of using laser cutting leaves rough surface and increases the chances of thrombosis, so it needs to be electropolished to reach smooth surface. The purpose of this study is to determine the effect of electropolishing parameter variations such as working voltage, electrolyte temperature, and electropolishing time on surface roughness reduction of 316L stainless steel material for coronary stent applications and find recommended parameter variations. Forty-five specimens with the initial surface roughness 45pm-55pm are electropolished. The electropolishing process involves 3 parameters: voltage, electrolyte temperature, and processing time. Then, comparison between initial and final condition of surface roughness is done. The results show different results for every combination. The best electropolishing process is shown with a value 16,8% on surface roughness reduction, and the worst one is -17,71%. Recommended variation of parameter is: 3 volts (working voltage), 35°C (electrolyte temperature), and 4 minutes (processing time). This recommendation is based on the lowest parameter and highest reduction in surface roughness with the aim to reduce cost and time production with the best smoothing result.