Effect of pre-oxidation on the isothermal and cyclic oxidation behaviour of cold-sprayed NiCoCrAlY coating. (November 2015)

• Record Type: Journal Article
• Authors: Xie, S. F.; Zhang, L. W.; Ning, X. J.; Wang, L.; Lu, D. P.
• Is Part Of: Materials research innovations. Volume 19(2015)Supplement 9
• Page Start: S9-258
• Page End: S9-262
• Publication Date: 2015-11
• Subjects: NiCoCrAlY -- Cold spray -- Pre-oxidation -- Oxidation -- Thermally grown oxide; Materials -- Research -- Periodicals; Matériaux -- Recherche -- Périodiques; 620.1105
• DOI: 10.1179/1432891715Z.0000000001979
• Languages: English
• ISSNs: 1432-8917

Abstract

Abstract : The effects of vacuum pre-oxidation treatment on the isothermal and cyclic oxidation behaviour of a cold-sprayed NiCoCrAlY coating are investigated. It is found that the cold-sprayed NiCoCrAlY coating has a dense structure with low oxygen content and consists of a single γ -matrix phase. A uniform and continuous α -Al2 O3 layer with a thickness of 0.47 ± 0.02 μm can be obtained by pre-oxidation treatment in a vacuum environment. The pre-oxidation treatment decreases the growth rate of thermally grown oxide by the formation of Al2 O3 with larger grain sizes and thus improves the thermal cyclic life of coating. Surface-geometry imperfections are the source of initial spallation of thermally grown oxide.