Abstract Ceramic sensors based on TiO 2 -Y 2 O 3 systems with different amounts of tetraethyl orthosilicate (TEOS) were thermally cycled in the temperature range of either 39–742 °C or 39–749 °C for 10, 50 and 100 cycles. The thermal wave imaging (TWI) technique, a nondestructive evaluation method, was used to characterize the bonding of sensor films with the substrate. Based on the thermal wave signal amplitudes, an assessment of bond strength was made. The results indicate that samples between 2 to 5% TEOS show the best bonding characteristics.