Corrosion of Ni-Cr alloys in chlorine (Cl2) gases containing 0 vol% to 5.0 vol% water (H2O) vapor between 400°C and 700°C was investigated using thermodynamic analysis and examination of corrosion products by x-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive x-ray spectroscopy (EDS), and x-ray photoelectron spectroscopy (XPS). Corrosion behavior of Ni-Cr alloys in the environments studied occurred by chlorination and oxidation simultaneously. Results indicated overall kinetics of corrosion in this temperature range were influenced by the presence of water vapor. With increasing temperature, the lower partial pressure of H2O (⁠PH2O⁠) had little effect on the corrosion process. At higher PH2O⁠, the corrosion rate decreased because of formation of a condensed Cr2O3-rich layer on the surface of the corrosion product scale formed on the Ni-Cr alloys.

Subject
Water, Corrosion kinetics, Corrosion rate, Nickel based alloys, Atmosphere, Mixtures, Partial pressures, Vapors, Corrosion products, Corrosion scales, Oxide scales, Scale formation, Chlorides
Keywords:
chlorination, chromium, corrosion behavior, energy-dispersive x-ray spectroscopy, high-temperature corrosion, nickel, oxidation, scanning electron microscopy, thermodynamic analysis, vapor pressure
NACE International
1997
You do not currently have access to this content.