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Study on hot corrosion behavior of Yb 2 Zr 2 O 7 ceramic against Na 2 SO 4 + V 2 O 5 molten salts at temperatures of 900–1200 °C in air
Author(s) -
Li S.,
Liu Z.G.,
Ouyang J.H.
Publication year - 2012
Publication title -
materials and corrosion
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.487
H-Index - 55
eISSN - 1521-4176
pISSN - 0947-5117
DOI - 10.1002/maco.201005779
Subject(s) - materials science , calcination , molten salt , scanning electron microscope , vanadium , corrosion , ceramic , salt (chemistry) , precipitation , metallurgy , coprecipitation , nuclear chemistry , analytical chemistry (journal) , inorganic chemistry , catalysis , chemistry , composite material , biochemistry , physics , meteorology , chromatography
Yb 2 Zr 2 O 7 ceramic powders synthesized by chemical‐coprecipitation and calcination method were pressureless‐sintered at 1700 °C for 10 h in air to fabricate dense bulk materials. Hot corrosion studies were performed on Yb 2 Zr 2 O 7 against Na 2 SO 4 and Na 2 SO 4 + V 2 O 5 (molar ratio = 1:1) molten salts in a temperature range of 900–1200 °C for 8 h in air, respectively. Chemical reactions were investigated using X‐ray diffraction (XRD) and scanning electron microscopy (SEM). The Yb 2 Zr 2 O 7 ceramic was severely corroded by Na 2 SO 4 + V 2 O 5 molten salt, however, no chemical reaction was found between individual Na 2 SO 4 and Yb 2 Zr 2 O 7 . Yb 2 Zr 2 O 7 reacted with Na 2 SO 4 + V 2 O 5 molten salt to form YbVO 4 and m ‐ZrO 2 . The thickness of hot corrosion scales formed at different temperatures was investigated to evaluate hot corrosion behavior based on fluxing mechanism. The introduction of vanadium into sulfate led to subsequent formation of NaVO 3 , which was acidic enough to dissolve Yb 2 Zr 2 O 7 by acidic fluxing.