Initial Stages of the HCl-Induced High-Temperature Corrosion of Alloy 310

Polished 310 stainless steel coupons were exposed isothermally in a horizontal tube furnace at for . The exposure gas consisted of with 5% and HCl(g). The corroded samples were analyzed by X-ray diffraction, focused ion beam microanalysis, scanning electron microscopy with energy-dispersive X-ray analysis, and by Auger electron spectroscopy. Mass gain was recorded. As expected, HCl(g) is a corrosion accelerator, the dominating corrosion products being , , and . A tentative mechanism for the initial stages of the HCl-induced corrosion of stainless steel is presented.