OXIDATION AND SULFIDATION BEHAVIOR OF FE-20CR-16NI-4AL-1Y2O3 OXIDE-DISPERSION-STRENGTHENED ALLOY

High-temperature oxidation and sulfidation studies were conducted on an oxide-dispersion-strengthened alloy of composition Fe-20Cr-16Ni-4Al-1Y2O3. The oxidation studies were conducted in air and low-PO2 environments over a temperature range of 650-1200-degrees-C. Results are also reported on the sulfidation resistance of preformed oxide scales and the influence of reoxidation of preformed sulfide scales. Detailed microstructural results and x-ray diffraction analysis data are presented to substantiate the corrosion behavior of the alloy over the wide range of conditions anticipated in fossil-energy systems. Data are also presented on the corrosion behavior of the alloy in oxygen-sulfur mixed gas atmospheres, and the results are used to compare the corrosion behavior of the present alloy with other chromia- and alumina-forming alloys.