X-ray photoelectron spectroscopy (XPS), angular-dependent XPS and x-ray-induced Auger electron spectroscopy (XAES) have been used to investigate impurity (Si, Na and Al) segregation in 25.5 wt.% CeO2-2.5 Y2O3-72 ZrO2 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 approximately 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.
XPS investigation of impurity phase segregation in 25.5 wt.% CeO2-2.5 Y2O3-72 ZrO2 plasma-sprayed thermal barrier coatings
GM Ingo;
1990
Abstract
X-ray photoelectron spectroscopy (XPS), angular-dependent XPS and x-ray-induced Auger electron spectroscopy (XAES) have been used to investigate impurity (Si, Na and Al) segregation in 25.5 wt.% CeO2-2.5 Y2O3-72 ZrO2 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 approximately 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.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
