Investigation of reactions between vanadium oxide and plasma-sprayed yttria-stabilized zirconia coatings

Journal Article · Thu Jan 01 00:00:00 EST 2009 · Journal of European Ceramic Society

DOI:https://doi.org/10.1016/j.jeurceramsoc.2008.09.016· OSTI ID:964340

Chen, Zun ^[1]; Speakman, Scott A ^[2]; Howe, Jane Y ^[2]; Wang, Hsin ^[2]; Porter, Wallace D ^[2]; Trice, Rodney ^[1]

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1. Purdue University
2. ORNL

The phase evolution occurring during the reaction between corrosive V{sub 2}O{sub 5} (T{sub m} = 690 C) and a plasma-sprayed 7 wt.% Y{sub 2}O{sub 3}ZrO{sub 2} (YSZ) coating from 700 to 900 C has been investigated in situ by X-ray diffraction. The temperature and time of interaction between the V{sub 2}O{sub 5} and YSZ coating determines the phases observed. Between 700 and 750 C, reaction products of ZrV{sub 2}O{sub 7} and YVO{sub 4} were observed within minutes of reaching the test temperature. m-ZrO{sub 2} was observed after 220 and 60 min at 700 and 750 C, respectively. The simultaneous formation of both ZrV{sub 2}O{sub 7} and YVO{sub 4} at the beginning of the reaction along with the delay of the m-ZrO{sub 2} formation suggests similar reactivity between both Zr and Y with V{sub 2}O{sub 5}. The weight percent of the ZrV{sub 2}O{sub 7} phase began to diminish after 150 and 60 min at 700 and 750 C, respectively. For reaction temperatures of 800 and 900 C, there is a rapid decrease in the amount of t{prime}-ZrO{sub 2} and a rapid increase in the amount of m-ZrO{sub 2} with reaction time. YVO{sub 4} was also observed at these reaction temperatures. SEM and TEM microstructural observations confirmed the phases detected from the in situ XRD experiments. Reactions between YSZ and V{sub 2}O{sub 5} suggest that the formation of a liquid phase due to the high solubility of both zirconia and yttria in vanadia is the dominate mechanism that damages the coating. The thermal conductivity of a plasma-sprayed YSZ coating reacted with up to 1 wt.% V{sub 2}O{sub 5} did not significantly change due to the small volume affected.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). High Temperature Materials Lab. (HTML)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE)
• DOE Contract Number: DE-AC05-00OR22725
• OSTI ID: 964340
• Journal Information: Journal of European Ceramic Society, Vol. 29, Issue 8
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
COATINGS
SOLUBILITY
THERMAL CONDUCTIVITY
VANADIUM OXIDES
YTTRIUM OXIDES
ZIRCONIUM OXIDES
CORROSIVE EFFECTS
PHASE STUDIES
ZrO2
corrosoin
V2O5
Y2O3