TY - GEN
T1 - Characterization of isothermally oxidized ZrO2-8wt.%Y 2O3 thermal barrier coatings by electrochemical impedance spectroscopy
AU - Byeon, J. W.
AU - Jayaraj, B.
AU - Sohn, Y. H.
PY - 2005
Y1 - 2005
N2 - Electrochemical impedance spectroscopy was employed to examine ZrO 2-8wt.%Y2O3 (yttria stabilized zirconia, YSZ) thermal barrier coating (TBC) as a function of isothermal exposure time at 1121°C. Electrochemical impedance response (resistance and capacitance of YSZ and thermally grown oxide (TGO)) of TBC specimens was analyzed with an alternative current equivalent circuit based on the multi-layered micro-constituents of TBC, and the impedance response was correlated with microstructural changes attributed to isothermal oxidation. The resistance of YSZ was observed to increase initially and then decrease with thermal exposure. The initial increase was related to the high temperature sintering of YSZ, and the subsequent decrease was discussed in terms of microcrack initiation and electrolyte penetration. The TGO thickness was linearly correlated to the capacitance of TGO.
AB - Electrochemical impedance spectroscopy was employed to examine ZrO 2-8wt.%Y2O3 (yttria stabilized zirconia, YSZ) thermal barrier coating (TBC) as a function of isothermal exposure time at 1121°C. Electrochemical impedance response (resistance and capacitance of YSZ and thermally grown oxide (TGO)) of TBC specimens was analyzed with an alternative current equivalent circuit based on the multi-layered micro-constituents of TBC, and the impedance response was correlated with microstructural changes attributed to isothermal oxidation. The resistance of YSZ was observed to increase initially and then decrease with thermal exposure. The initial increase was related to the high temperature sintering of YSZ, and the subsequent decrease was discussed in terms of microcrack initiation and electrolyte penetration. The TGO thickness was linearly correlated to the capacitance of TGO.
KW - Electrochemical impedance spectroscopy
KW - Isothermal oxidation
KW - Nondestructive evaluation
KW - Thermal barrier coating
KW - Thermally grown oxide
UR - http://www.scopus.com/inward/record.url?scp=35148901171&partnerID=8YFLogxK
U2 - 10.4028/0-87849-966-0.145
DO - 10.4028/0-87849-966-0.145
M3 - Conference contribution
AN - SCOPUS:35148901171
SN - 0878499660
SN - 9780878499663
T3 - Materials Science Forum
SP - 145
EP - 148
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 -