ENVIRONMENTAL SCANNING ELECTRON-MICROSCOPY FOR DYNAMIC CORROSION STUDIES OF STAINLESS-STEEL PIPING USED IN UHP GAS-DISTRIBUTION SYSTEMS

An ElectroScan ESEM was used for in situ corrosion studies on cold dra wn electropolished 316L stainless steel tube surfaces in the as-receiv ed and passivated conditions. Corrosion product was removed as it form ed and the tube surface was viewed before, during, and after corrosive attack. The corrosion process was followed iri situ, and the sample f eatures most susceptible to corrosion (draw lines, inclusions, etc.) w ere identified. In addition, X-ray photoelectron spectroscopy (XPS) wa s used to study the changes in surface chemistry after corrosive attac k. This information provided clear evidence of relevant corrosion mech anisms and relative corrosion susceptibility. (C) 1993 Wiley-Liss, Inc .