XPS investigation of impurity phase segregation in 25.5 wt.% CeO2−2.5 Y2O3−72 ZrO2 plasma-sprayed thermal barrier coatings

✍ Scribed by M. Arfelli; G. M. Ingo; G. Mattogno

• Publisher: John Wiley and Sons
• Year: 1990
• Tongue: English
• Weight: 471 KB
• Volume: 16
• Category: Article
• ISSN: 0142-2421
• DOI: 10.1002/sia.740160193

✦ Synopsis

Abstract

X‐ray photoelectron spectroscopy (XPS), angular‐dependent XPS and x‐ray‐inducd Auger electron spectroscopy (XAES) have been used to investigate impurity (Si, Na and Al) segregation in 25.5 wt.% CeO~2~−2.5 Y~2~O~3~−72 ZrO~2~ plasma‐sprayed thermal barrier coatings (TBCs) as a function of high‐temperature air thermal treatment (up to 1460°C). The segregated phase, present in a similar composition both on the as‐thermally treated and fracture surfaces, forms a thin layer of ∼20 nm thick. This phase contains both silicon and sodium at a temperature ranging between 900 and 1350°C and it is also enriched with aluminium at higher temperatures. The XPS and XAES results are used to identify the chemical composition of this surface phase.