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Thermal diffusivity (a) of YSZ coatings was determined by the phase lag method of the photo-acoustic signal for rear and frontal illuminations using a two-beam photo-acoustic cell. XRD results show the presence of a tetragonal phase with (101) and (112) orientations, and FTIR spectra exhibit the 2Eu and F1u modes as two broad bands in the frequency at 453 cm � 1 ,4 68 cm � 1 , corresponding to the tetragonal phase of ZrO2. Thermal diffusivity was measured in the Si/YSZ system and also on the Si (100) substrate from which a simple two-layer system model. Via specific heat measurements at constant pressure (Cp) using the (DSC) technique, and mass density (r) calculations using Archimedes and Aleksandrov's methods for both in-bulk and film YSZ samples, thermal conductivity (k) was obtained. The results were: a ¼ (0.0021 � 0.0002) and (0.0023 � 0.0002) cm 2 s � 1 , r ¼ (4.7725 � 0.005) � 10 3 and (5.883 � 0.005) � 10 3 kg m � 3 , Cp ¼ (427 � 14) J kg � 1 K � 1 ,a ndk ¼ (0.43 � 0.06) and (0.57 � 0.06) W m � 1 K � 1 for in-bulk and film YSZ samples, respectively. |
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