In Situ ESEM Investigation of KCl-Induced Corrosion of a FeCrAl and a Model FeNiCrAl Alloy in Lab Air at 450 degrees C
Artikel i vetenskaplig tidskrift, 2015

The very early stages of KCl-induced corrosion of a FeCrAl and a FeNiCrAl alloy in an 0211420 environment were studied using in-situ Environmental Scanning Electron Microscopy (ESEM). The samples were KCl contaminated and then exposed to lab air at a total pressure of 4.8 Ton at 450 degrees C. After exposure, the samples were analyzed using SEM-EDX, FIB and STEM-EDX. For both alloys, fast oxide growth occurred at the KCl particles. Far away from the KCl particles, a thin base oxide formed with potassium chromate nodules on top. The base oxide was layered, consisting of iron-chromium oxide on top and alumina in the bottom part. The FeCrAl alloy suffered internal oxidation while the FeNiCrAl did not. Both alloys formed sub-scale chlorides. A mechanism is proposed for the reaction of KCl on the surface and for the formation of different surface features at the KCl particles.

rmany

v56

high-temperature corrosion

dry o-2

oxide scale

sanicro 28

p801

initial-stages

water-vapor

superheater materials

Materials Science

kanthal af

Electrochemistry

biomass

oxidation

Författare

Nooshin Mortazavi Seyedeh

Chalmers, Teknisk fysik, Materialens mikrostruktur

Luciana Intiso

Chalmers, Teknisk fysik, Materialens mikrostruktur

Niklas Israelsson

Chalmers University of Technology

Lars-Gunnar Johansson

Chalmers University of Technology

Mats Halvarsson

Chalmers, Teknisk fysik, Materialens mikrostruktur

Journal of the Electrochemical Society

0013-4651 (ISSN)

Vol. 162 C744-C753

Ämneskategorier

Metallurgi och metalliska material

Styrkeområden

Materialvetenskap

DOI

10.1149/2.0581514jes