Water Vapor Effects on the Oxidation Behavior of Fe-Cr and Ni-Cr Alloys in Atmospheres Relevant to Oxy-fuel Combustion

Journal Article · Sat Oct 01 04:00:00 EDT 2011 · Oxidation of Metals

DOI:https://doi.org/10.1007/s11085-012-9302-x· OSTI ID:1114764

Mu, N.; Jung, K. Y.; Yanar, N. M.; Meier, G. H.; Pettit, F. S.; Holcomb, G. R.

The oxidation behavior of a number of Fe–Cr- and Ni–Cr-based alloys was studied in atmospheres relevant to oxyfuel combustion at 650 °C. Oxidation was greatly enhanced in ferritic model alloys exposed in low p(O{sub 2}) CO{sub 2} + 30%H{sub 2}O and Ar + 30%H{sub 2}O gases. Rapidly growing iron oxides appear to be porous and gas permeable. Transition from non-protective to protective oxidation occurs on alloys with higher Cr contents between 13.5 and 22 wt% in H{sub 2}O. Excess oxygen, usually found in the actual oxyfuel combustion environments, disrupts the selective oxidation of Fe–Cr alloys by accelerating vaporization of early-formed Cr{sub 2}O{sub 3} in combination with accelerated chromia growth induced by the H{sub 2}O. Rapid Cr consumption leads to the nucleation and rapid growth of iron oxides. On the contrary, Ni–Cr alloys are less affected by the presence of H{sub 2}O and excess O{sub 2}. The difference between Fe–Cr and Ni–Cr alloys is not clear but is postulated to involve less acceleration of chromia growth by water vapor for the latter group of alloys.

• Research Organization: National Energy Technology Laboratory - In-house Research; National Energy Technology Laboratory (NETL), Pittsburgh, PA, and Morgantown, WV (United States)
• Sponsoring Organization: USDOE Office of Fossil Energy (FE)
• DOE Contract Number: FE0004000
• OSTI ID: 1114764
• Report Number(s): TPR-3866
• Journal Information: Oxidation of Metals, Journal Name: Oxidation of Metals Journal Issue: 3 - 4 Vol. 78
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
Chromia
Ferritic alloys
Iron oxides
Oxy-fuel combustion
Water vapor