Porosity Characterization of Thermal Barrier Coatings by Ultrasound with Genetic Algorithm Backpropagation Neural Network

Table 2

Material parameters in numerical calculation of ultrasonic testing.

Medium	(MPa)	(MPa)	(MPa)	Density (kg·m^−3)	(m/s)
ZrO2 coating	142740	70039	36200	6500	2957.65
20°C air	0.1467	0.1467	0	1.24	344