Title

Characterization of long-term oxidized nickel aluminide coating by photoluminescence spectroscopy

Authors

Authors

J. W. Byeon; N. Mu; J. Liu;Y. H. Sohn

Comments

Authors: contact us about adding a copy of your work at STARS@ucf.edu

Keywords

nickel aluminide coating; isothermal oxidation; thermally grown oxide; photoluminescence spectroscopy; nondestructive evaluation; OXIDE SCALES; Engineering, Environmental; Materials Science, Multidisciplinary

Abstract

Microstructures and residual stress of long-term oxidized nickel aluminide coating on superalloy were evaluated by photostimulated luminescence spectroscopy (PSLS). CMSX-4 superalloy coupons coated with single phase beta-NiAl were oxidized in air at 788, 871, 954 and 1010 degrees C for up to 10000 hours. The photoluminescence technique was applied for the analysis of the phase constituents and the residual stress of the thermally grown oxide (TGO) scale formed on the coating, together with transmission electron microscopy. According to the PSLS analysis, TGO consisted of both stable alpha-Al2O3 and metastable Al2O3 phases in specimens oxidized at 788 degrees C and 871 degrees C. At higher temperatures, the TGO scale primarily consisted of equilibrium alpha-Al2O3. The compressive residual stress within TGO increased up to about 3GPa with increasing oxidation temperature and time until local spallation, after which a decrease as well as large standard deviation of residual stress was observed owing to the stress-relief associated with TGO scale spallation.

Journal Title

Eco-Materials Processing & Design Vi

Volume

486-487

Publication Date

1-1-2005

Document Type

Article

Language

English

First Page

141

Last Page

144

WOS Identifier

WOS:000230389400036

ISSN

0255-5476; 0-87849-966-0

Share

COinS