The microstructural evolution of IN617 subjected to oxidising atmospheres of 100% steam, 50%
steam/argon and air in the temperature range 700-750oC for exposures times up to 4,000 h at
atmospheric pressure has been investigated using a range of analytical electron microscopy
techniques. It has been found that for this alloy the presence of steam in the atmosphere has an effect
on the oxidation kinetics, and influences the nature of the scale. It has also been shown that there are
differences in the volume and nature of voids formed, and that the voids are often associated with an
internal structure of alumina. Significant internal oxidation was observed, particularly in the presence
of steam, and a 3D reconstruction of the microstructure using FIBSEM techniques showed that this
comprised of interconnected alumina plates which followed the grain boundaries into the substrate.
Funding
The authors would like to acknowledge financial support from both EPSRC [Grant No. EP/G037345/1] through the Doctoral Training Centre in Efficient Fossil Energy Technologies and Alstom Power Ltd.
History
School
Aeronautical, Automotive, Chemical and Materials Engineering
Department
Materials
Published in
MATERIALS AT HIGH TEMPERATURES
Volume
29
Issue
2
Pages
81 - 88 (8)
Citation
GORMAN, D.M. ... et al, 2012. Microstructural analysis of steam oxidation of IN617 for use in ultra-supercritical steam plants. Materials at High Temperatures, 29 (2), pp. 81 - 88.
This article was accepted for publication in the journal Materials at High Temperatures, http://www.maneyonline.com/mht. The definitive version is available at: http://www.maneyonline.com/doi/abs/10.1179/096034012X13313071300779