Influence of Water Vapour on a Nickel-Based Alloy Oxidation

Water vapour has little effect on the oxidation rate and scale composition of a nickel-based SY 625 alloy oxidized between 900 and 1100°C. At 900 and 1000°C, the outer scale is composed of Cr2O3 and a continuous NbNi4 - Ni3Mo subscale is found at the oxide/alloy interface. At 1100°C the scale is composed of an outer chromia scale and an internal CrNbO4 subscale. The oxide scale morphology differs between dry and wet conditions. Under dry conditions the oxide scale appears to be compact and chromia pegs are observed at the internal interface. Under wet conditions, porosities are observed inside the scale. At 1100°C some scale spallation is observed under dry and wet conditions.

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Influence of Water Vapour on Isothermal and Thermal Cyclic Oxidation Conditions of a Nickel-Based SY625 Steel at 1100°C

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.323-325.333 ◽

2012 ◽

Vol 323-325 ◽

pp. 333-338

Author(s):

Raphaël Rolland ◽

Henri Buscail ◽

Christophe Issartel ◽

Frédéric Riffard ◽

Françoise Rabaste ◽

...

Keyword(s):

Grain Size ◽

Oxide Scale ◽

Water Vapour ◽

Cyclic Oxidation ◽

Isothermal Oxidation ◽

Chromia Scale ◽

Scale Spallation ◽

Oxidation Condition ◽

Dry Conditions ◽

Dry And Wet Conditions

In isothermal oxidation condition, water vapour has little effect on the oxidation rate and scale composition of a nickel-based SY 625 alloy oxidized at 1100°C. The scale is composed of an outer Cr2O3and an internal CrNbO4scale. The oxide scale morphology differs between dry and wet conditions. Under dry conditions the oxide scale appears to be compact and chromia pegs are observed at the internal interface. Under wet conditions, porosities are observed spread inside the scale and the chromia grain size is smaller. At this temperature some scale spallation is observed under dry and wet conditions. Under cyclic oxidation conditions the oxide scale adherence is slightly improved in wet environment. The chromia scale is adherent during the 4 first oxidation cycles. In dry air, spallation occured after the first cycle. In dry and wet conditions, after the chromia scale spallation has started, NiO and NiCr2O4form first. NiMoO4forms later on the alloy surface during the cycling test. The best resistance of the alloy under thermal cycling conditions under wet conditions is related to the presence of a more plastic and adherent scale owing to a higher scale porosity and smaller chromia grain size compared to dry conditions.

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Influence of water vapour pressure on the thermal dehydration of lithium sulphate monohydrate

Solid State Ionics ◽

10.1016/0167-2738(93)90130-u ◽

1993 ◽

Vol 63-65 ◽

pp. 363-366 ◽

Cited By ~ 15

Author(s):

F ROUQUEROL ◽

Y LAUREIRO ◽

J ROUQUEROL

Keyword(s):

Water Vapour ◽

Vapour Pressure ◽

Thermal Dehydration ◽

Water Vapour Pressure ◽

Lithium Sulphate ◽

Influence Of Water

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Effect of substrate thickness on oxide scale spallation for solid oxide fuel cells

Corrosion Science ◽

10.1016/j.corsci.2011.03.025 ◽

2011 ◽

Vol 53 (7) ◽

pp. 2406-2412 ◽

Cited By ~ 10

Author(s):

W.N. Liu ◽

X. Sun ◽

E. Stephens ◽

M. Khaleel

Keyword(s):

Fuel Cells ◽

Solid Oxide Fuel Cells ◽

Oxide Scale ◽

Solid Oxide ◽

Substrate Thickness ◽

Oxide Fuel ◽

Scale Spallation

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Influence of water vapour and tar compound on laminar flame speed of gasified biomass gas

Applied Energy ◽

10.1016/j.apenergy.2012.03.010 ◽

2012 ◽

Vol 98 ◽

pp. 114-121 ◽

Cited By ~ 11

Author(s):

Nur Farizan Munajat ◽

Catharina Erlich ◽

Reza Fakhrai ◽

Torsten H. Fransson

Keyword(s):

Water Vapour ◽

Laminar Flame ◽

Flame Speed ◽

Laminar Flame Speed ◽

Influence Of Water

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New particle formation during α- and β-pinene oxidation by O<sub>3</sub>, OH and NO<sub>3</sub>, and the influence of water vapour: particle size distribution studies

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-2-469-2002 ◽

2002 ◽

Vol 2 (2) ◽

pp. 469-506 ◽

Cited By ~ 1

Author(s):

B. Bonn ◽

G. K. Moortgat

Keyword(s):

Particle Size ◽

Water Vapour ◽

Particle Formation ◽

New Particle Formation ◽

Oxidation Reactions ◽

Scanning Mobility Particle Sizer ◽

Volume Yield ◽

Influence Of Water ◽

The Individual ◽

Aerosol Volume

Abstract. New particle formation during the oxidation of a- and b-pinene (C10H16) by ozone, OH and NO3 was studied by measuring the particle size distributions with a scanning mobility particle sizer (TSI 3936). The results indicate a drastically higher nucleation potential of the ozonolysis than in the reaction with either OH or NO3. On the contrary, the contribution of the individual oxidation reactions to form new aerosol volume was found to depend on the location of the carbon double bond to be oxidized: for the endocyclic a-pinene reactions the ozonolysis contributed mostly to the aerosol volume yield, whereas for the exocyclic b-pinene reactions the oxidation by O3, OH and NO3 yielded a similar aerosol volume. In a second part of this study the influence of water vapour on the nucleation in all three possible oxidation routes was examined. The observations revealed only an effect of water vapour during the ozonolysis reactions.

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