TY - GEN
T1 - Characterization of long-term oxidized nickel aluminide coating by photoluminescence spectroscopy
AU - Byeon, J. W.
AU - Mu, N.
AU - Liu, J.
AU - Sohn, Y. H.
PY - 2005
Y1 - 2005
N2 - 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 β-NiAl were oxidized in air at 788, 871, 954 and 1010°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 α-Al 2O3 and metastable Al2O3 phases in specimens oxidized at 788°C and 871°C. At higher temperatures, the TGO scale primarily consisted of equilibrium α-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.
AB - 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 β-NiAl were oxidized in air at 788, 871, 954 and 1010°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 α-Al 2O3 and metastable Al2O3 phases in specimens oxidized at 788°C and 871°C. At higher temperatures, the TGO scale primarily consisted of equilibrium α-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.
KW - Isothermal oxidation
KW - Nickel aluminide coating
KW - Nondestructive evaluation
KW - Thermally grown oxide photoluminescence spectroscopy
UR - https://www.scopus.com/pages/publications/35148845250
U2 - 10.4028/0-87849-966-0.141
DO - 10.4028/0-87849-966-0.141
M3 - Conference contribution
AN - SCOPUS:35148845250
SN - 0878499660
SN - 9780878499663
T3 - Materials Science Forum
SP - 141
EP - 144
BT - Eco-Materials Processing and Design VI - Proceedings of the 6th International Symposium on Eco-Materials Processing and Design, ISEPD-6
PB - Trans Tech Publications Ltd
T2 - 6th International Symposium on Eco-Materials Processing and Design, ISEPD-6
Y2 - 16 January 2005 through 18 January 2005
ER -