In Situ Investigation of the Oxidation of Cobalt-Base Superalloys in the Environmental Scanning Electron Microscope

Since their discovery in 2006, cobalt‐base superalloys have aroused increasing interest as potential materials for various high‐temperature applications. One of the still unsolved problems is their resistance to oxidation. In the present study, the very first stages of the oxidation process of a Co–...

Full description

Saved in:
Bibliographic Details
Published in:Advanced engineering materials 2015-08, Vol.17 (8), p.1158-1167
Main Authors: Weiser, Martin, Reichmann, Angelika, Albu, Mihaela, Virtanen, Sannakaisa, Poelt, Peter
Format: Article
Language:English
Subjects:
Chambers
Cobalt base alloys
Crystallites
Crystallography
Grain boundaries
Orientation
Oxidation
Scanning electron microscopy
Superalloys
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Since their discovery in 2006, cobalt‐base superalloys have aroused increasing interest as potential materials for various high‐temperature applications. One of the still unsolved problems is their resistance to oxidation. In the present study, the very first stages of the oxidation process of a Co–9Al–9W alloy were investigated. To this aim, the progress of the oxidation process was continuously observed at high magnification in an environmental scanning electron microscope (ESEM). Oxidation starts not necessarily at the grain boundaries, and both the onset temperature and the oxidation rate depend on the crystallographic orientation of the crystallites. A heating stage mounted in the specimen chamber of an environmental scanning electron microscope (Figure) enables the continuous observation of the development of the corrosive structures during hot corrosion experiments. The temperature, at which the oxidation of the material starts, can be determined, and the dependence of the corrosion process on the crystallographic orientation of individual grains can be observed.
ISSN:1438-1656
1527-2648
DOI:10.1002/adem.201500146