Improvement of the Oxidation Resistance of CoNiCrAlY Bond Coats Sprayed by High Velocity Oxygen-Fuel onto Nickel Superalloy Substrate

CoNiCrAlY powders with similar granulometry and chemical composition, but different starting reactivity toward oxygen, were sprayed onto superalloy substrates by High Velocity Oxygen-Fuel producing coatings of similar thicknesses. After spraying, samples were maintained at 1,273 K in air for differe...

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Bibliographic Details
Main Authors: Alessio Fossati, Martina Di Ferdinando, Alessandro Lavacchi, Andrea Scrivani, Carlo Giolli, Ugo Bardi
Format: Article
Language:English
Published: MDPI AG 2010-11-01
Series:Coatings
Subjects:
Online Access:http://www.mdpi.com/2079-6412/1/1/3
Description
Summary:CoNiCrAlY powders with similar granulometry and chemical composition, but different starting reactivity toward oxygen, were sprayed onto superalloy substrates by High Velocity Oxygen-Fuel producing coatings of similar thicknesses. After spraying, samples were maintained at 1,273 K in air for different test periods of up to 5,000 hours. Morphological, microstructural, compositional and electrochemical analyses were performed on the coated samples in order to assess the high temperature oxidation resistance provided by the two different powders. The powder with higher starting reactivity towards oxygen improves the oxidation resistance of the coated samples by producing thinner and more adherent thermally grown oxide layers.
ISSN:2079-6412