| Summary: | Promoting molten calcium–magnesium–alumina–silicate (CMAS) crystallization can highly reduce the melt penetration into thermal barrier coatings (TBCs), which alleviates its corrosion to TBCs. In marine environments, many salts are coupled with CMAS. In this study, we investigated the crystallization behavior of CMAS + NaCl/NaSO4, and pointed out its influence on the corrosion behavior of TBCs. At 1200 ℃, CMAS + NaCl was crystalized into CaMgSi2O6, CaSiO3 and CaAl2Si2O8, while the crystallization products of CMAS + NaSO4 depended on NaSO4 content, i.e., 4 wt.% and 10 wt.% NaSO4 addition leading to CaAl2Si2O8 and Ca2Al(AlSiO7) phases, respectively, in addition to CaMgSi2O6 and CaSiO3. At 1100 ℃, CMAS + NaSO4 crystalized, while CMAS + NaCl had no crystallization. At lower temperatures, both NaCl and NaSO4 additions could suppress CMAS crystallization. It reveals that CMAS coupled with molten salt is hard to crystallize, which is detrimental to corrosion protection.
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