Corrosion behavior of Fe(Ni)CrAlX alloys in an HCl-H{sub 2}O-H{sub 2} gas mixture at 800{degrees}C

Journal Article · Thu Jun 01 04:00:00 EDT 1995 · Oxidation of Metals

DOI:https://doi.org/10.1007/BF01046895· OSTI ID:96459

Chu, H; Datta, P K; Strafford, K N ^[1]

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1. Univ. of Northumbria, Newcastle (United Kingdom)

The high-temperature-corrosion behavior of a series of Fe(Ni)CrAlX-type alloys (where X = Zr and Hf, e.g.) has been studied in a gas mixture of 50% HCl-10% H{sub 2}O-H{sub 2} at 800{degrees}C. The experimental results obtained indicated that Ni-base alloys had superior corrosion resistance to Fe-base alloys in this gas mixture. While the exposed Ni-base alloys showed weight gains due to the formation of oxides (e.g., Al{sub 2}O{sub 3}, Cr{sub 2}O{sub 3}) as well as CrCl{sub 2}, the Fe-base alloys exhibited substantial weight losses resulting from the formation and subsequent evaporation of FeCl{sub 2}. This study also demonstrated that Fe(Ni) Cr8AlX-type alloys, which contained high aluminum, had better chloridation resistance than Fe(Ni)25CrAlX-type alloys, which had high chromium. The improved performance of Fe(Ni)Cr8-AlX-type alloys was due to the presence of a high level of aluminum which promoted the formation of protective Al{sub 2}O{sub 3}. Although the presence of chromium in the alloys promoted the formation of Cr{sub 2}O{sub 3}, the high level of chromium adversely affected the chloridation resistance of Fe(Ni)25CrAlX-type alloys, due to the development of chloride (CrCl{sub 2}) at the interface of the oxide scale and alloy substrate.

• Sponsoring Organization: USDOE
• OSTI ID: 96459
• Journal Information: Oxidation of Metals, Journal Name: Oxidation of Metals Journal Issue: 5-6 Vol. 43; ISSN OXMEAF; ISSN 0030-770X
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM ALLOYS
CHROMIUM ALLOYS
CHROMIUM CHLORIDES
CORROSION
CORROSIVE EFFECTS
CRYSTAL STRUCTURE
HYDROCHLORIC ACID
HYDROGEN
IRON BASE ALLOYS
MICROSTRUCTURE
SCALING
WATER