Spectral emittance measurements for ytterbium disilicate‐based environmental barrier coatings

Abstract The spectral reflectance and transmittance of two free‐standing ytterbium disilicate (Yb 2 Si 2 O 7 )—based environmental barrier coatings (EBCs) were measured from 25°C up to 1270°C. The measurements were collected over the spectral range of approximately 2–20 µm. The spectral emittance was then determined through conservation of energy and Kirchhoff's law of thermal radiation. The spectral emittance measurements for the EBCs were then compared to previous measurements for a thermal barrier coating (TBC).