High-Temperature Oxidation of FeCr(Ni) Alloys: The Behaviour After Breakaway
Journal article, 2017

The oxidation of an austenitic FeCr(Ni) steel at 600 A degrees C in H2O + KCl + O-2/H-2 + H2O + Ar environments is studied up to 168 h. The oxidation behaviour after "breakaway" is investigated by microstructural investigations, and thermodynamic calculations (Thermo-Calc) on the FeCr(Ni)-O system are used to interpret the results. The characteristic "breakaway" scale morphology exhibits an outward-growing iron oxide and a bottom layer consisting of inward-growing spinel oxide and reaction zones containing Cr-rich oxide precipitates and Cr-depleted metal. The equilibrium calculations show that a miscibility gap appears in the FeCr spinel oxide below 665 A degrees C influencing the microstructure of the inward-growing scale. Equilibrium calculations on the FeCrNi-O system show that Ni is not expected to enter the spinel oxide in low oxygen activity conditions, in accordance with observations.

Internal oxidation

Stainless steel

High-temperature oxidation

Breakaway corrosion

Author

Torbjörn Jonsson

Chalmers, Chemistry and Chemical Engineering, Energy and Material, Environmental Inorganic Chemistry

H. Larsson

Thermo-Calc Software AB

Sofia Karlsson

Chalmers, Chemistry and Chemical Engineering, Energy and Material, Environmental Inorganic Chemistry

Hamed Hoseini Hooshyar

Chalmers, Chemistry and Chemical Engineering, Energy and Material, Environmental Inorganic Chemistry

Mohammad Sattari

Chalmers, Chemistry and Chemical Engineering, Energy and Material, Environmental Inorganic Chemistry

Jesper Liske

Chalmers, Chemistry and Chemical Engineering, Energy and Material, Environmental Inorganic Chemistry

Jan-Erik Svensson

Chalmers, Chemistry and Chemical Engineering, Energy and Material, Environmental Inorganic Chemistry

Lars-Gunnar Johansson

Chalmers, Chemistry and Chemical Engineering, Energy and Material, Environmental Inorganic Chemistry

Oxidation of Metals

0030-770X (ISSN) 1573-4889 (eISSN)

Vol. 87 3-4 333-341

Subject Categories

Materials Chemistry

DOI

10.1007/s11085-017-9731-7

More information

Latest update

4/11/2018