Microstructural investigations of pure nickel exposed to KCl induced high temperature corrosion
Journal article, 2015

Oxidation of 99.99% pure nickel was studied with and without 0.10 mg cm(-2) KCl(s) in an environment containing 5 vol.-% O-2, 40 vol.-% H2O and 55 vol.-% N-2 at 600 degrees C for up to 168 h. Oxide microstructure was investigated by X-ray diffraction (XRD), focused ion beam (FIB), broad ion beam (BIB) and SEM/ EDX. Oxidised nickel shows an approximately parabolic oxide growth rate. The oxide scale is dense with some pores at the oxide/metal interface. Adding small amounts of KCl does not result in a faster corrosion rate of nickel. However, the surface morphology changes and small oxide crusts were observed in the vicinity of former KCl particles. This is proposed to be the result of a NiCl2-KCl eutectic on top of the oxide scale formed above 514 degrees C. The oxide scale formed in the presence of KCl contains more and differently distributed voids than the scale formed without KCl.

600 degrees C

KCl

Nickel

Electron microscopy

High temperature corrosion

Author

Torbjörn Jonsson

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

Andreas Slomian

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

T. N. Lomholt

Technical University of Denmark (DTU)

S. Kiamehr

Technical University of Denmark (DTU)

K. V. Dahl

Technical University of Denmark (DTU)

Materials at High Temperatures

0960-3409 (ISSN)

Vol. 32 1-2 44-49

Subject Categories

Metallurgy and Metallic Materials

DOI

10.1179/0960340914z.00000000060

More information

Latest update

2/28/2018