Corrosion mechanisms of ZrO2-Y2O3 thermal barrier coatings in the presence of molten middle-east sand
نویسندگان
چکیده
The deposition of mineral debris in the turbine sections of various jet engines occurred after operation on Middle-East routes. Plasma sprayed Zr02-Yn03 thermal barrier coatings were aged with sand samples from several Middle-East locations at temperatures of 1200 to 1500 OC. At temperatures above 1400 OC, the molten sand formed glassy silicate debris that penetrated the ceramic coating completely, resulting in the absorption of Zr02 and Y 2 0 3 into the silicate. Two corrosion mechanisms were identified, determined by the amount of calciumbased minerals in the sand.
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