PlumX Metrics
Embed PlumX Metrics

NaSO + NaCl molten salts corrosion mechanism of thermal barrier coatings used in ships

Journal of Thermal Analysis and Calorimetry, ISSN: 1588-2926, Vol: 144, Issue: 6, Page: 2043-2056
2021
  • 4
    Citations
  • 0
    Usage
  • 3
    Captures
  • 0
    Mentions
  • 0
    Social Media
Metric Options:   Counts1 Year3 Year

Metrics Details

Article Description

6–8 mass% YO stabilized ZrO (6–8YSZ) thermal barrier coatings (TBCs) are widely applied to protect the hot ends of gas turbines in large navy ships. In this work, the 8YSZ TBCs were prepared by air plasma spraying technique, and their microstructure and phase composition were investigated. The hot corrosion mechanism of YSZ TBCs in molten salts consisting of 80% NaSO + 20% NaCl at 900 °C was comprehensively analyzed. The results showed that the corrosion product Y(SO) was formed due to the reaction between NaSO media and the stabilizer YO. As the result of the depletion of YO phase, the transformation from the tetragonal phase to monoclinic phase of ZrO could not been totally inhibited, which consequently induced the 4–6 vol.% expansion and more cracks of YSZ TBCs. Meanwhile, the cracks could work as transfer paths for oxygen and molten salts. The kinetic analysis on hot corrosion also showed that more reaction products (from 2 to 8.1 mg cm) were generated from 20 to 60 h due to more cracks generated by molten salts and oxygen infiltrating. More thermal grown oxides generated between ceramic layer, bonding layer and substrate, and the volume expansion caused by phase transition, increased the stresses in the coatings. Consequently, the peeling-off failure of 8YSZ TBCs could happen.

Provide Feedback

Have ideas for a new metric? Would you like to see something else here?Let us know