The corrosion of Fe-Mo alloys in H sub 2 /H sub 2 O/H sub 2 S atmospheres

Journal Article · Mon Jun 01 04:00:00 EDT 1992 · Oxidation of Metals; (United States)

DOI:https://doi.org/10.1007/BF00666627· OSTI ID:7019028

Kai, W; Douglass, D L ^[1]; Gesmundo, F ^[2]

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1. Univ. of California, Los Angeles (United States)
2. Univ. di Genova (Italy)

The corrosion of Fe-Mo alloys containing up to 40 wt.% Mo was studied over the temperature range 600-980 C. in a H{sub 2}/H{sub 2}O/H{sub 2}S mixture having a sulfur pressure of 10{sup {minus}5}atm. and an oxygen pressure of 10{sup {minus}20}atm. at 850 C. All alloys were two-phase, consisting of an Fe-rich solid solution and an intermetallic compound, Fe{sub 3}Mo{sub 2}. The scales formed on Fe-Mo alloys were bilayered, consisting of an outer layer of iron sulfide (FeS) and a complex inner layer whose composition and microstructure were a function of the reaction temperature and of the Mo content of the alloys. No oxides formed under any conditions. The corrosion kinetics followed the parabolic rate law at all temperatures. The addition of Mo caused only a slight decrease of the corrosion rate. Platinum markers were always located at the interface between the inner and outer scales, indicating that outer scale growth was primarily due to outward diffusion of iron, while the inner scale growth had a contribution from inward diffusion of sulfur.

• OSTI ID: 7019028
• Journal Information: Oxidation of Metals; (United States), Journal Name: Oxidation of Metals; (United States) Vol. 37:5-6; ISSN 0030-770X; ISSN OXMEA
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010404 -- Coal
Lignite
& Peat-- Gasification
36 MATERIALS SCIENCE
360105* -- Metals & Alloys-- Corrosion & Erosion
ACTIVATION ENERGY
ALLOYS
CHALCOGENIDES
CHEMICAL ANALYSIS
CHEMICAL REACTIONS
COAL GASIFICATION
CORROSION
CORROSION PRODUCTS
CORROSION RESISTANT ALLOYS
CORROSIVE EFFECTS
DATA
DIAGRAMS
DISPERSIONS
ELECTRON MICROPROBE ANALYSIS
ELECTRON MICROSCOPY
ELEMENTS
ENERGY
EXPERIMENTAL DATA
FLUIDS
GASES
GASIFICATION
HYDROGEN
HYDROGEN COMPOUNDS
HYDROGEN SULFIDES
INFORMATION
INTERMETALLIC COMPOUNDS
IRON ALLOYS
IRON BASE ALLOYS
IRON COMPOUNDS
IRON SULFIDES
MICROANALYSIS
MICROSCOPY
MIXTURES
MOLYBDENUM ALLOYS
MOLYBDENUM COMPOUNDS
MOLYBDENUM SULFIDES
NONDESTRUCTIVE ANALYSIS
NONMETALS
NUMERICAL DATA
OPTICAL MICROSCOPY
OXIDATION
PARTIAL PRESSURE
PHASE DIAGRAMS
QUANTITY RATIO
REFRACTORY METAL COMPOUNDS
SCANNING ELECTRON MICROSCOPY
SOLID SOLUTIONS
SOLUTIONS
SULFIDATION
SULFIDES
SULFUR
SULFUR COMPOUNDS
TEMPERATURE RANGE
TEMPERATURE RANGE 0400-1000 K
TEMPERATURE RANGE 1000-4000 K
THERMOCHEMICAL PROCESSES
TRANSITION ELEMENT COMPOUNDS
VAPORS
WATER VAPOR