Effects of piezo-spectroscopic coefficients of 8 wt.% Y2O3 stabilized ZrO2 on residual stress measurement of thermal barrier coatings by Raman spectroscopy

✍ Scribed by W.G. Mao; Q. Chen; C.Y. Dai; L. Yang; Y.C. Zhou; C. Lu

• Publisher: Elsevier Science
• Year: 2010
• Tongue: English
• Weight: 723 KB
• Volume: 204
• Category: Article
• ISSN: 0257-8972
• DOI: 10.1016/j.surfcoat.2010.04.024

✦ Synopsis

By using specially designed freestanding 8 wt.% Y 2 O 3 stabilized ZrO 2 (8YSZ) specimens, a linear relationship is found between the Raman peak shift, Δω, and applied uniaxial compressive stress, σ̅ u , i.e., Δω = Π u σ̅ u with Π u being the piezo-spectroscopic coefficient. The linear relationship is used to determine the in-plane residual stress in air plasma-sprayed 8YSZ thermal barrier coatings (TBCs). It is shown that the Π u of the 8YSZ is an exponential function of the thermal cycle N for a given thermal cycling process: Π u = 37.6exp (-N/25.9) + 13. Based on these two relationships, the actual residual stress of 8YSZ TBCs determined by the Raman spectroscopy method is quantitatively consistent with that obtained by the X-ray diffraction.