Sensitivity study of parameters in a hybrid electrochemical-mechanical polishing process for 316L stainless steel

The PEMEC process is a new polishing process designed for complex metal parts with high surface roughness. This new hybrid process has been developed by simultaneously coupling tribofinishing and electrochemical polishing. The PEMEC process improves surface roughness in just a few minutes, while preserving edge shape, and is based on a strong synergistic effect between abrasive and chemical mechanisms. To better understand this synergy, it is essential to know which parameters have the greatest influence on polishing results. To this end, it was decided to study the most influential parameters of the two processes combined in PEMEC: drag speed (tribofinishing) as well as temperature and voltage (electropolishing). This article focusses on the influence of each of these parameters on the PEMEC process, using a multi-scale analysis that simultaneously considers surface roughness, edge geometry, and sample dimensions. For each of the three parameters, the various observable impacts on the sample are described and quantified. Analysis of the results showed that temperature and voltage have a considerable impact on the PEMEC process and are able to modify the mechanisms of the process, as well as material removal rate. In comparison, drag speed has a smaller influence on the process. • PEMEC hybrid polishing quickly smoothens high-roughness surfaces • PEMEC creates a synergistic effect between abrasive and chemical mechanisms • Temperature and voltage are the most influential parameters of the process