Development of protective coatings to improve high temperature corrosion resistance in chlorine containing environments based on an advanced corrosion risk assessment tool

The presence of chlorine in several areas of chemical industry, as well as in waste incinerators or plastic/polymer decomposition mills, may significantly reduce the life-time of the plant components due to its significant corrosivity potential. The development of protective metallic coatings is one of the solutions that may be taken to promote the long-term resistance of structural materials involved in these processes. A helpful tool can be corrosion prediction diagrams for designing optimized coating compositions. For this reason, a new concept for the assessment of high temperature corrosion resistance in oxygen-chlorine containing environments has been developed. This development was based on an evaluation of the state-of-the-art and was leading to the concept of the “dynamic” quasistability diagram. This new type of diagram is based not only on thermodynamic considerations (as for the diagrams existing so far) but also on the products and reactants flow through a gas boundary layer formed on the material surface. “Dynamic” quasi-stability diagrams, which were validated by kinetics investigations of pure metallic elements, suggest that Ni-Al and Ni-Mo-Al systems should be particularly suitable as protective coatings. In the present work such coatings were developed and characterized. After exposure tests under “oxidising” and “reducing” conditions, NiAlMo APS-coatings offered a higher corrosion protection potential than NiAl APS-coatings under both conditions. Under “reducing” environments, NiAlMo APS-coatings showed a particularly high corrosion resistance in comparison with conventional Ni-base and Fe-base alloys investigated in previous work.

Grantor dc:publisher

Publikationsserver der RWTH Aachen University

Year dc:date

2009

Author dc:creator

• Latreche, Hadj

Contributors dc:contributor

• Schütze, Michael

• info:eu-repo/classification/ddc/620
• Hochtemperaturkorrosion
• Beschichtung
• Ingenieurwissenschaften
• high temperature corrosion
• coating

Statement dc:rights

• info:eu-repo/semantics/openAccess

Language dc:language

eng

Identifier

https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-113545%22

OAI record oai:identifier

https://publications.rwth-aachen.de/oai2d?verb=GetRecord&metadataPrefix=oai_dc&identifier=oai%3Apublications.rwth-aachen.de%3A51233