Corrosion Rate Evaluation of Pulse Electrochemical Polishing for Stainless Steel

摘要

Pulse electrochemical polishing (PECP) is used to improve mechanical properties, such roughness and corrosion resistance. In addition, it is used remove deformed layers created by machining processes. The application of pulse voltage based on an analysis of the electrical double-layer charging process enables high-resolution electrochemical polishing (ECP). The variables of the PECP process are mainly defined in terms of several parameters, including the gap between electrodes, pulse time, and process time. PECP can provide a smooth, bright, reflective, and deburred surface that exhibits superior corrosion resistance. The objective of this paper is to study the corrosion resistance of PECP for stainless steel 316L. Scanning electron microscopy (SEM) is used to observe surface characteristics. The surface roughness of a pulse electrochemically polished sample is measured by atomic force microscopy (AFM). Auger electron spectroscopy (AES) is applied to analyze the metallurgical composition and the thickness of the passive film.