Observations on Pit Initiation Behavior of Carbon Steel Using Microelectrochemical System with Confocal Laser Scanning Microscopy

Abstract

A microelectrochemical system equipped with a confocal laser scanning microscopy was applied to the real-time observation of pit initiation in the pearlite structure of carbon steel. By using this system, high-resolution images of pit initiation process could be obtained. It was revealed that the initiation site of pitting was in a ferrite lamella, and the pit propagated along the lamellar structure. The cementite remained in the very early stage of pitting.