Mechanical properties and microstructure of VPS and HVOF CoNiCrAlY coatings

Saeidi, S and Voisey, K.T. and McCartney, D.G. (2011) Mechanical properties and microstructure of VPS and HVOF CoNiCrAlY coatings. Journal of Thermal Spray Technology, 20 (6). pp. 1231-1243. ISSN 1059-9630

[img]
Preview
PDF - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
Download (3MB) | Preview

Abstract

HVOF and VPS coatings were sprayed using a Praxair (CO-210-24) CoNiCrAlY powder. Free standing coatings underwent vacuum annealing at different temperatures for times of up to 840h. Feedstock powder, as-sprayed and annealed coatings were characterised by SEM, EDS and XRD. The hardness and Young’s modulus of as-sprayed and annealed HVOF and VPS coatings were measured, including determination of Young’s moduli of the individual phases via nanoindentation and measurement of Young’s moduli of coatings at temperatures up to 500°C. The Eshelby inclusion model was used to investigate the effect of microstructure on the coatings’ mechanical properties. The sensitivity of the mechanical properties to microstructural details was confirmed. Young’s modulus was constant to ~200°C then decreased with increasing measurement temperature. Annealing increased Young’s modulus due to a combination of decreased porosity and β volume fraction. Oxide stringers in the HVOF coating maintained its higher hardness than the VPS coating even after annealing.

Item Type: Article
Additional Information: The final publication is available at Springer via http://dx.doi.org/10.1007/s11666-011-9666-5
Keywords: coatings for gas turbine components; hardness and (visco-)elastic properties; heat treatment of coatings; properties of coatings; stiffness
Schools/Departments: University of Nottingham UK Campus > Faculty of Engineering
Identification Number: https://doi.org/10.1007/s11666-011-9666-5
Depositing User: Voisey, Dr KT
Date Deposited: 28 Jan 2015 18:03
Last Modified: 16 Sep 2016 20:01
URI: http://eprints.nottingham.ac.uk/id/eprint/28076

Actions (Archive Staff Only)

Edit View Edit View