Efficient Sampling Method for Evaluating Atmospheric Corrosivity Using Sputter-Cleaned Metal Surface

Abstract

We proposed a new efficient sampling method for evaluating atmospheric corrosivity influenced by airborne sea salt and/or pollutants. X-ray Photoelectron Spectroscopy (XPS) was employed to analyze chlorine and sulfur captured in the top most thin layer of corrosion films. These elements are the main components of airborne sea-salt-particles and/or pollutants, both of which promote corrosion. Copper and silver specimens with super-clean surfaces pretreated by Ar⁺-ion sputtering were exposed to three different atmospheres for a period of 1 hour, before and after which they were preserved in a vacuum carrying vessel. XPS was sensitive enough to detect minute amounts of the target elements, which well reflect the atmospheric corrosivity, at the early stages of corrosion. This demonstrates that this method is useful for quick evaluation of atmospheric corrosivity.